nouri-App/nouri/main.py

from __future__ import annotations

from collections import defaultdict
from datetime import date, datetime, timedelta
from itertools import product
from pathlib import Path

from flask import (
    Blueprint,
    after_this_request,
    current_app,
    flash,
    g,
    jsonify,
    redirect,
    render_template,
    request,
    send_file,
    url_for,
)

from .auth import admin_required, login_required
from .backup import RESTORE_CONFIRMATION_TEXT, export_backup_archive, restore_backup_archive
from .constants import (
    AVAILABILITY_LABELS,
    BUILDER_LABELS,
    DEFAULT_CATEGORY_BUILDERS,
    DAY_TEMPLATE_NAME_SUGGESTIONS,
    DEFAULT_CATEGORIES,
    ENERGY_DENSITY_LABELS,
    ENERGY_DENSITY_OPTIONS,
    ITEM_KIND_LABELS,
    ITEM_KIND_SINGULAR_LABELS,
    ITEM_SET_NAME_SUGGESTIONS,
    NOTIFICATION_CHANNEL_OPTIONS,
    SUGGESTION_STYLE_LABELS,
    SUGGESTION_STYLE_OPTIONS,
    VISIBILITY_DESCRIPTIONS,
    VISIBILITY_LABELS,
    WEEKDAY_OPTIONS,
    WEEK_TEMPLATE_NAME_SUGGESTIONS,
)
from .db import get_db
from .images import (
    allowed_image_file,
    save_photo_with_variants,
    upload_file_size_ok,
)
from .push import push_is_configured, push_public_key, send_push_message


main_bp = Blueprint("main", __name__)
ACTIVE_STATE_OPTIONS = [
    ("", "Alle aktiven"),
    ("home", "Zuhause"),
    ("idea", "Merkliste"),
]
KIND_FILTER_OPTIONS = [
    ("", "Alles"),
    ("food", "Lebensmittel"),
    ("meal", "Mahlzeitenideen"),
]
VISIBILITY_FILTER_OPTIONS = [
    ("", "Alles Sichtbare"),
    ("shared", "Gemeinsam"),
    ("personal", "Persönlich"),
]
VISIBILITY_FORM_OPTIONS = [
    ("shared", "Gemeinsam"),
    ("personal", "Persönlich"),
]
TARGET_USER_OPTIONS_DEFAULT = "__all__"
WEEKDAY_LABELS = ["Montag", "Dienstag", "Mittwoch", "Donnerstag", "Freitag", "Samstag", "Sonntag"]


@main_bp.before_app_request
def refresh_due_context():
    endpoint = request.endpoint or ""
    if getattr(g, "user", None) is None:
        return None
    if request.method == "GET" and endpoint.startswith("main."):
        ensure_user_settings_row()
        activate_due_shopping_needs()
    return None


def current_household_id() -> int:
    return int(g.user["household_id"])


def get_dayparts() -> list:
    return get_db().execute("SELECT * FROM dayparts ORDER BY sort_order").fetchall()


def get_household_users(active_only: bool = True):
    query = """
        SELECT id, username, display_name, role
        FROM users
        WHERE household_id = ?
    """
    params: list[object] = [current_household_id()]
    if active_only:
        query += " AND is_active = 1"
    query += " ORDER BY LOWER(COALESCE(display_name, username))"
    return get_db().execute(query, params).fetchall()


def get_target_user_options() -> list[dict]:
    options = [{"value": TARGET_USER_OPTIONS_DEFAULT, "label": "Für alle"}]
    for user in get_household_users():
        options.append(
            {
                "value": str(user["id"]),
                "label": user["display_name"] or user["username"],
            }
        )
    return options


def get_category_options(include_inactive_selected: str | None = None) -> list[str]:
    rows = get_db().execute(
        """
        SELECT name
        FROM household_categories
        WHERE household_id = ? AND is_active = 1
        ORDER BY sort_order, LOWER(name)
        """,
        (current_household_id(),),
    ).fetchall()
    categories = [row["name"] for row in rows]
    if not categories:
        categories = DEFAULT_CATEGORIES[:]
    if include_inactive_selected and include_inactive_selected not in categories:
        categories.append(include_inactive_selected)
    return categories


def get_category_builder_map() -> dict[str, str]:
    rows = get_db().execute(
        """
        SELECT name, builder_key
        FROM household_categories
        WHERE household_id = ?
        """,
        (current_household_id(),),
    ).fetchall()
    builder_map = {row["name"]: (row["builder_key"] or "neutral") for row in rows}
    for name, builder_key in DEFAULT_CATEGORY_BUILDERS.items():
        builder_map.setdefault(name, builder_key)
    return builder_map


def get_household_settings() -> dict:
    row = get_db().execute(
        """
        SELECT shopping_weekday, shopping_prep_days, shopping_reminder_time
        FROM households
        WHERE id = ?
        """,
        (current_household_id(),),
    ).fetchone()
    if row is None:
        return {
            "shopping_weekday": 5,
            "shopping_prep_days": 1,
            "shopping_reminder_time": "18:00",
        }
    return {
        "shopping_weekday": int(row["shopping_weekday"] or 5),
        "shopping_prep_days": int(row["shopping_prep_days"] or 1),
        "shopping_reminder_time": row["shopping_reminder_time"] or "18:00",
    }


def ensure_user_settings_row() -> None:
    get_db().execute(
        "INSERT OR IGNORE INTO user_settings (user_id) VALUES (?)",
        (g.user["id"],),
    )


def get_user_settings() -> dict:
    ensure_user_settings_row()
    row = get_db().execute("SELECT * FROM user_settings WHERE user_id = ?", (g.user["id"],)).fetchone()
    if row is None:
        return {}
    settings = dict(row)
    boolean_fields = {
        "reminders_enabled",
        "push_enabled",
        "remind_before_shopping",
        "remind_on_shopping_day",
        "show_missing_for_upcoming_week",
        "show_planned_not_shopped",
        "remind_tomorrow_if_sparse",
        "remind_week_if_sparse",
        "push_missing_breakfast",
        "push_missing_lunch",
        "push_missing_dinner",
        "suggest_home_for_today",
        "remind_small_snack",
        "remind_nuts",
        "show_meal_balancing",
        "suggest_templates",
        "suggest_patterns",
    }
    for field in boolean_fields:
        settings[field] = bool(settings.get(field))
    settings["notification_channel"] = settings.get("notification_channel") or "in_app"
    settings["suggestion_style"] = normalize_suggestion_style(settings.get("suggestion_style"), "balanced")
    settings["energy_preference"] = suggestion_style_energy_preference(settings["suggestion_style"])
    return settings


def parse_checkbox(name: str, default: bool = False) -> int:
    return 1 if request.form.get(name, "1" if default else "0") == "1" else 0


def normalize_weekday(raw: str | None, default: int = 5) -> int:
    if raw and raw.isdigit():
        value = int(raw)
        if 0 <= value <= 6:
            return value
    return default


def normalize_notification_channel(raw: str | None, default: str = "in_app") -> str:
    allowed = {value for value, _label in NOTIFICATION_CHANNEL_OPTIONS}
    return raw if raw in allowed else default


def normalize_suggestion_style(raw: str | None, default: str = "balanced") -> str:
    allowed = {value for value, _label in SUGGESTION_STYLE_OPTIONS}
    if raw == "easy" or raw == "snack":
        return "balanced"
    return raw if raw in allowed else default


def normalize_energy_density(raw: str | None, default: str = "neutral") -> str:
    allowed = {value for value, _label in ENERGY_DENSITY_OPTIONS}
    return raw if raw in allowed else default


def suggestion_style_energy_preference(style: str) -> str:
    if style == "fitness":
        return "low"
    return "neutral"


def visible_clause(table_alias: str) -> str:
    return (
        f"{table_alias}.household_id = ? "
        f"AND ({table_alias}.visibility = 'shared' OR {table_alias}.owner_user_id = ?)"
    )


def visible_params() -> list[int]:
    return [current_household_id(), int(g.user["id"])]


def parse_week_start(raw: str | None) -> date:
    if raw:
        try:
            parsed = datetime.strptime(raw, "%Y-%m-%d").date()
            return parsed - timedelta(days=parsed.weekday())
        except ValueError:
            pass
    today = date.today()
    return today - timedelta(days=today.weekday())


def parse_plan_date(raw: str | None, fallback: date | None = None) -> date:
    if raw:
        try:
            return datetime.strptime(raw, "%Y-%m-%d").date()
        except ValueError:
            pass
    return fallback or date.today()


def normalize_visibility(raw: str | None, default: str = "shared") -> str:
    return raw if raw in VISIBILITY_LABELS else default


def normalize_target_user_id(raw: str | None) -> int | None:
    if not raw or raw == TARGET_USER_OPTIONS_DEFAULT:
        return None
    if not raw.isdigit():
        return None
    target_id = int(raw)
    allowed = {int(user["id"]) for user in get_household_users()}
    return target_id if target_id in allowed else None


def save_photo(upload, current_filename: str | None = None) -> str | None:
    if not upload or not upload.filename:
        return current_filename
    if not allowed_image_file(upload.filename):
        raise ValueError("Bitte ein Bild als PNG, JPG, GIF oder WEBP hochladen.")
    if not upload_file_size_ok(upload, current_app.config["MAX_CONTENT_LENGTH"]):
        raise ValueError("Das Bild ist gerade zu groß. Ein etwas kleineres Foto hilft hier am besten.")
    return save_photo_with_variants(upload, current_app.config["UPLOAD_FOLDER"], current_filename=current_filename)


def user_display_name(display_name: str | None, username: str | None) -> str:
    return display_name or username or "Haushalt"


def describe_record(entry: dict) -> dict:
    owner_name = user_display_name(entry.get("owner_display_name"), entry.get("owner_username"))
    target_name = user_display_name(entry.get("target_display_name"), entry.get("target_username")) if entry.get("target_user_id") else None
    entry["owner_name"] = owner_name
    entry["target_name"] = target_name
    entry["energy_density"] = normalize_energy_density(entry.get("energy_density"), "neutral")
    entry["energy_density_label"] = ENERGY_DENSITY_LABELS.get(entry["energy_density"], ENERGY_DENSITY_LABELS["neutral"])
    entry["is_personal"] = entry.get("visibility") == "personal"
    entry["is_shared"] = entry.get("visibility") == "shared"
    entry["is_mine"] = entry.get("owner_user_id") == g.user["id"]
    entry["visibility_label"] = VISIBILITY_LABELS.get(entry.get("visibility"), "Gemeinsam")
    entry["visibility_description"] = VISIBILITY_DESCRIPTIONS.get(entry.get("visibility"), "")
    entry["owner_label"] = "Von mir" if entry["is_mine"] else f"Von {owner_name}"
    entry["for_label"] = f"Für {target_name}" if target_name else "Für alle"
    entry["can_edit"] = entry["is_shared"] or entry["is_mine"] or g.user["role"] == "admin"
    return entry


def describe_records(rows) -> list[dict]:
    return [describe_record(dict(row)) for row in rows]


def describe_template_record(entry: dict) -> dict:
    owner_name = user_display_name(entry.get("owner_display_name"), entry.get("owner_username"))
    entry["owner_name"] = owner_name
    entry["is_mine"] = entry.get("owner_user_id") == g.user["id"]
    entry["visibility_label"] = VISIBILITY_LABELS.get(entry.get("visibility"), "Gemeinsam")
    entry["owner_label"] = "Von mir" if entry["is_mine"] else f"Von {owner_name}"
    entry["can_edit"] = entry.get("visibility") == "shared" or entry["is_mine"] or g.user["role"] == "admin"
    return entry


def ensure_can_edit(entry: dict, error_message: str = "Diesen Eintrag kannst du gerade nicht bearbeiten.") -> None:
    if not (entry.get("can_edit") or g.user["role"] == "admin"):
        raise PermissionError(error_message)


def get_item(item_id: int) -> dict:
    item = get_db().execute(
        f"""
        SELECT items.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username,
               EXISTS(
                   SELECT 1
                   FROM shopping_entries
                   WHERE shopping_entries.item_id = items.id AND shopping_entries.is_checked = 0
               ) AS is_on_shopping_list
        FROM items
        LEFT JOIN users AS owner ON owner.id = items.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        WHERE items.id = ? AND {visible_clause('items')}
        """,
        [item_id, *visible_params()],
    ).fetchone()
    if item is None:
        raise ValueError("Der Eintrag wurde nicht gefunden.")
    return describe_record(dict(item))


def get_item_daypart_ids(item_id: int) -> list[int]:
    rows = get_db().execute(
        "SELECT daypart_id FROM item_dayparts WHERE item_id = ?",
        (item_id,),
    ).fetchall()
    return [int(row["daypart_id"]) for row in rows]


def get_meal_component_ids(meal_id: int) -> list[int]:
    rows = get_db().execute(
        """
        SELECT meal_components.food_item_id
        FROM meal_components
        JOIN items ON items.id = meal_components.food_item_id
        WHERE meal_components.meal_item_id = ?
          AND items.household_id = ?
          AND (items.visibility = 'shared' OR items.owner_user_id = ?)
        """,
        (meal_id, current_household_id(), g.user["id"]),
    ).fetchall()
    return [int(row["food_item_id"]) for row in rows]


def attach_dayparts(items: list[dict]) -> list[dict]:
    if not items:
        return []

    item_ids = [item["id"] for item in items]
    placeholders = ",".join("?" for _ in item_ids)
    rows = get_db().execute(
        f"""
        SELECT item_dayparts.item_id, dayparts.id, dayparts.slug, dayparts.name
        FROM item_dayparts
        JOIN dayparts ON dayparts.id = item_dayparts.daypart_id
        WHERE item_dayparts.item_id IN ({placeholders})
        ORDER BY dayparts.sort_order
        """,
        item_ids,
    ).fetchall()
    grouped = defaultdict(list)
    for row in rows:
        grouped[row["item_id"]].append(
            {"id": row["id"], "slug": row["slug"], "name": row["name"]}
        )

    for item in items:
        item["dayparts_meta"] = grouped.get(item["id"], [])
        item["dayparts"] = [daypart["name"] for daypart in item["dayparts_meta"]]
        item["primary_daypart_id"] = item["dayparts_meta"][0]["id"] if item["dayparts_meta"] else None
    return items


def attach_components(items: list[dict]) -> list[dict]:
    meal_ids = [item["id"] for item in items if item["kind"] == "meal"]
    if not meal_ids:
        for item in items:
            item["components"] = []
            item["component_ids"] = []
        return items

    placeholders = ",".join("?" for _ in meal_ids)
    rows = get_db().execute(
        f"""
        SELECT meal_components.meal_item_id,
               meal_components.food_item_id,
               items.name
        FROM meal_components
        JOIN items ON items.id = meal_components.food_item_id
        WHERE meal_components.meal_item_id IN ({placeholders})
          AND items.household_id = ?
          AND (items.visibility = 'shared' OR items.owner_user_id = ?)
        ORDER BY LOWER(items.name)
        """,
        [*meal_ids, current_household_id(), g.user["id"]],
    ).fetchall()
    grouped_names: dict[int, list[str]] = defaultdict(list)
    grouped_ids: dict[int, list[int]] = defaultdict(list)
    for row in rows:
        grouped_names[row["meal_item_id"]].append(row["name"])
        grouped_ids[row["meal_item_id"]].append(int(row["food_item_id"]))

    for item in items:
        item["components"] = grouped_names.get(item["id"], [])
        item["component_ids"] = grouped_ids.get(item["id"], [])
    return items


def attach_builder_keys(items: list[dict]) -> list[dict]:
    if not items:
        return []

    category_builder_map = get_category_builder_map()
    meal_ids = [item["id"] for item in items if item["kind"] == "meal"]
    meal_builder_map: dict[int, set[str]] = defaultdict(set)

    if meal_ids:
        placeholders = ",".join("?" for _ in meal_ids)
        rows = get_db().execute(
            f"""
            SELECT meal_components.meal_item_id,
                   component.category
            FROM meal_components
            JOIN items AS component ON component.id = meal_components.food_item_id
            WHERE meal_components.meal_item_id IN ({placeholders})
            """,
            meal_ids,
        ).fetchall()
        for row in rows:
            builder_key = category_builder_map.get(row["category"] or "", "neutral")
            meal_builder_map[int(row["meal_item_id"])].add(builder_key)

    for item in items:
        builder_keys: list[str]
        if item["kind"] == "meal":
            builder_keys = sorted(meal_builder_map.get(item["id"], set()))
            if not builder_keys:
                builder_keys = [category_builder_map.get(item.get("category") or "", "neutral")]
        else:
            builder_keys = [category_builder_map.get(item.get("category") or "", "neutral")]
        item["builder_keys"] = builder_keys
        item["builder_labels"] = [BUILDER_LABELS.get(key, BUILDER_LABELS["neutral"]) for key in builder_keys]
        item["primary_builder_key"] = builder_keys[0] if builder_keys else "neutral"
    return items


def decorate_items(rows) -> list[dict]:
    return attach_builder_keys(attach_components(attach_dayparts(describe_records(rows))))


def fetch_builder_keys_for_item_ids(item_ids: list[int]) -> dict[int, set[str]]:
    if not item_ids:
        return {}
    category_builder_map = get_category_builder_map()
    placeholders = ",".join("?" for _ in item_ids)
    rows = get_db().execute(
        f"""
        SELECT id, kind, category
        FROM items
        WHERE id IN ({placeholders})
        """,
        item_ids,
    ).fetchall()
    builder_map: dict[int, set[str]] = {int(row["id"]): {category_builder_map.get(row["category"] or "", "neutral")} for row in rows}
    meal_ids = [int(row["id"]) for row in rows if row["kind"] == "meal"]
    if meal_ids:
        meal_placeholders = ",".join("?" for _ in meal_ids)
        component_rows = get_db().execute(
            f"""
            SELECT meal_components.meal_item_id, component.category
            FROM meal_components
            JOIN items AS component ON component.id = meal_components.food_item_id
            WHERE meal_components.meal_item_id IN ({meal_placeholders})
            """,
            meal_ids,
        ).fetchall()
        for row in component_rows:
            builder_map.setdefault(int(row["meal_item_id"]), set()).add(
                category_builder_map.get(row["category"] or "", "neutral")
            )
    return builder_map


def score_suggestion_components(component_items: list[dict], daypart_slug: str, settings: dict) -> int:
    builder_keys = {key for item in component_items for key in item.get("builder_keys", ["neutral"])}
    energy_values = [normalize_energy_density(item.get("energy_density"), "neutral") for item in component_items]
    score = 0

    style = settings.get("suggestion_style", "balanced")
    if style == "fitness":
        score += 9 if "protein" in builder_keys else 0
        score += 4 if daypart_slug in {"lunch", "dinner"} and "veg" in builder_keys else 0
        score += 2 if "carb" in builder_keys else 0
    elif style == "protein":
        score += 8 if "protein" in builder_keys else 0
        score += 3 if daypart_slug in {"lunch", "dinner"} and "veg" in builder_keys else 0
    else:
        if daypart_slug in {"breakfast", "morning-snack", "afternoon-snack", "late-snack"}:
            score += 5 if "carb" in builder_keys else 0
            score += 4 if builder_keys & {"dairy", "fruit", "nuts", "seeds"} else 0
        else:
            score += 5 if "protein" in builder_keys else 0
            score += 4 if "carb" in builder_keys else 0
            score += 4 if "veg" in builder_keys else 0

    energy_preference = settings.get("energy_preference", "neutral")
    if style == "fitness":
        score += energy_values.count("low") * 4
        score -= energy_values.count("high") * 2
    elif energy_preference == "high":
        score += energy_values.count("high") * 3
        score -= energy_values.count("low")
    elif energy_preference == "low":
        score += energy_values.count("low") * 3
        score -= energy_values.count("high")
    else:
        score += energy_values.count("neutral")

    return score


def fetch_items(
    *,
    kind: str | None = None,
    availability: str | None = None,
    include_archived: bool = False,
    query: str | None = None,
    daypart_id: int | None = None,
    visibility: str | None = None,
):
    conditions = [visible_clause("items")]
    params = visible_params()

    if kind:
        conditions.append("items.kind = ?")
        params.append(kind)
    if availability:
        conditions.append("items.availability_state = ?")
        params.append(availability)
    elif not include_archived:
        conditions.append("items.availability_state != 'archived'")
    if query:
        conditions.append("LOWER(items.name) LIKE ?")
        params.append(f"%{query.lower()}%")
    if daypart_id:
        conditions.append(
            """
            EXISTS (
                SELECT 1
                FROM item_dayparts
                WHERE item_dayparts.item_id = items.id
                  AND item_dayparts.daypart_id = ?
            )
            """
        )
        params.append(daypart_id)
    if visibility:
        conditions.append("items.visibility = ?")
        params.append(visibility)

    rows = get_db().execute(
        f"""
        SELECT items.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username,
               EXISTS(
                   SELECT 1
                   FROM shopping_entries
                   WHERE shopping_entries.item_id = items.id AND shopping_entries.is_checked = 0
               ) AS is_on_shopping_list
        FROM items
        LEFT JOIN users AS owner ON owner.id = items.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        WHERE {' AND '.join(conditions)}
        ORDER BY
            CASE items.availability_state WHEN 'home' THEN 0 WHEN 'idea' THEN 1 ELSE 2 END,
            CASE items.visibility WHEN 'shared' THEN 0 ELSE 1 END,
            LOWER(items.name)
        """,
        params,
    ).fetchall()
    return decorate_items(rows)


def fetch_food_options(query: str | None = None):
    return fetch_items(kind="food", include_archived=True, query=query)


def group_items_by_availability(items: list[dict]) -> list[dict]:
    grouped = defaultdict(list)
    for item in items:
        grouped[item["availability_state"]].append(item)

    result = []
    for state in ("home", "idea", "archived"):
        entries = grouped.get(state, [])
        if entries:
            result.append({"state": state, "title": AVAILABILITY_LABELS[state], "items": entries})
    return result


def extract_item_form_data(existing: dict | None = None) -> dict:
    form_data = existing or {}
    form_data.update(
        {
            "name": request.form.get("name", "").strip(),
            "category": request.form.get("category", "").strip(),
            "energy_density": normalize_energy_density(request.form.get("energy_density"), form_data.get("energy_density", "neutral")),
            "note": request.form.get("note", "").strip(),
            "visibility": normalize_visibility(request.form.get("visibility"), form_data.get("visibility", "shared")),
            "target_user_id": normalize_target_user_id(request.form.get("target_user_id")),
            "target_user_raw": request.form.get("target_user_id", TARGET_USER_OPTIONS_DEFAULT),
            "food_search": request.form.get("food_search", "").strip(),
            "daypart_ids": [int(value) for value in request.form.getlist("daypart_ids") if value.isdigit()],
            "component_ids": [int(value) for value in request.form.getlist("component_ids") if value.isdigit()],
            "quick_food_name": request.form.get("quick_food_name", "").strip(),
            "quick_food_category": request.form.get("quick_food_category", "").strip(),
            "quick_food_energy_density": normalize_energy_density(request.form.get("quick_food_energy_density"), form_data.get("quick_food_energy_density", "neutral")),
            "quick_food_note": request.form.get("quick_food_note", "").strip(),
        }
    )
    return form_data


def create_quick_food_from_form(form_data: dict) -> int:
    cursor = get_db().execute(
        """
        INSERT INTO items (
            household_id, owner_user_id, target_user_id, visibility, kind, name, category, energy_density, note, created_by, updated_by
        )
        VALUES (?, ?, ?, ?, 'food', ?, ?, ?, ?, ?, ?)
        """,
        (
            current_household_id(),
            g.user["id"],
            form_data["target_user_id"],
            form_data["visibility"],
            form_data["quick_food_name"],
            form_data["quick_food_category"],
            form_data["quick_food_energy_density"],
            form_data["quick_food_note"],
            g.user["id"],
            g.user["id"],
        ),
    )
    food_id = int(cursor.lastrowid)
    sync_item_dayparts(food_id, form_data["daypart_ids"])
    get_db().commit()
    return food_id


def shopping_activation_date_for(needed_date: date) -> date:
    settings = get_household_settings()
    shopping_weekday = int(settings["shopping_weekday"])
    prep_days = int(settings["shopping_prep_days"])
    days_back = (needed_date.weekday() - shopping_weekday) % 7
    shopping_date = needed_date - timedelta(days=days_back)
    return shopping_date - timedelta(days=prep_days)


def should_activate_shopping_need(needed_date: date, today: date | None = None) -> bool:
    return (today or date.today()) >= shopping_activation_date_for(needed_date)


def schedule_shopping_need(
    *,
    item_id: int,
    user_id: int,
    visibility: str,
    needed_for_date: str,
    needed_for_daypart_id: int | None,
    source_item_id: int | None = None,
) -> bool:
    activation_date = shopping_activation_date_for(parse_plan_date(needed_for_date))
    existing = get_db().execute(
        """
        SELECT id
        FROM shopping_needs
        WHERE household_id = ?
          AND item_id = ?
          AND COALESCE(source_item_id, 0) = COALESCE(?, 0)
          AND needed_for_date = ?
          AND COALESCE(needed_for_daypart_id, 0) = COALESCE(?, 0)
          AND visibility = ?
          AND is_activated = 0
        LIMIT 1
        """,
        (
            current_household_id(),
            item_id,
            source_item_id,
            needed_for_date,
            needed_for_daypart_id,
            visibility,
        ),
    ).fetchone()
    if existing:
        get_db().execute(
            """
            UPDATE shopping_needs
            SET activation_date = ?,
                owner_user_id = ?
            WHERE id = ?
            """,
            (activation_date.isoformat(), user_id, existing["id"]),
        )
    else:
        get_db().execute(
            """
            INSERT INTO shopping_needs (
                household_id,
                owner_user_id,
                visibility,
                item_id,
                source_item_id,
                needed_for_date,
                needed_for_daypart_id,
                activation_date,
                created_by
            )
            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
            """,
            (
                current_household_id(),
                user_id,
                visibility,
                item_id,
                source_item_id,
                needed_for_date,
                needed_for_daypart_id,
                activation_date.isoformat(),
                g.user["id"],
            ),
        )
    get_db().commit()
    return True


def add_to_shopping_list(
    item_id: int,
    user_id: int,
    *,
    visibility_override: str | None = None,
    needed_for_date: str | None = None,
    needed_for_daypart_id: int | None = None,
) -> bool:
    item = get_item(item_id)
    existing = get_db().execute(
        """
        SELECT id FROM shopping_entries
        WHERE item_id = ? AND is_checked = 0
        """,
        (item_id,),
    ).fetchone()
    if existing:
        return False

    visibility = normalize_visibility(visibility_override, item["visibility"])
    owner_user_id = user_id if visibility == "personal" else item["owner_user_id"]
    get_db().execute(
        """
        INSERT INTO shopping_entries (
            household_id, owner_user_id, visibility, item_id, added_by, needed_for_date, needed_for_daypart_id
        )
        VALUES (?, ?, ?, ?, ?, ?, ?)
        """,
        (
            current_household_id(),
            owner_user_id,
            visibility,
            item_id,
            user_id,
            needed_for_date,
            needed_for_daypart_id,
        ),
    )
    get_db().commit()
    return True


def fetch_meal_missing_components(meal_id: int) -> list[dict]:
    rows = get_db().execute(
        """
        SELECT items.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username,
               0 AS is_on_shopping_list
        FROM meal_components
        JOIN items ON items.id = meal_components.food_item_id
        LEFT JOIN users AS owner ON owner.id = items.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        WHERE meal_components.meal_item_id = ?
          AND items.household_id = ?
          AND (items.visibility = 'shared' OR items.owner_user_id = ?)
          AND items.availability_state != 'home'
        ORDER BY LOWER(items.name)
        """,
        (meal_id, current_household_id(), g.user["id"]),
    ).fetchall()
    return attach_builder_keys(attach_dayparts(describe_records(rows)))


def ensure_item_or_missing_components_are_shopped(
    item_id: int,
    user_id: int,
    visibility: str,
    *,
    needed_for_date: str | None = None,
    needed_for_daypart_id: int | None = None,
    source_item_id: int | None = None,
) -> dict:
    item = get_item(item_id)
    if item["kind"] == "meal":
        missing_components = fetch_meal_missing_components(item_id)
        if missing_components:
            added_names = []
            scheduled_names = []
            for component in missing_components:
                if needed_for_date and not should_activate_shopping_need(parse_plan_date(needed_for_date)):
                    schedule_shopping_need(
                        item_id=component["id"],
                        user_id=user_id,
                        visibility=visibility,
                        needed_for_date=needed_for_date,
                        needed_for_daypart_id=needed_for_daypart_id,
                        source_item_id=source_item_id or item_id,
                    )
                    scheduled_names.append(component["name"])
                else:
                    added = add_to_shopping_list(
                        component["id"],
                        user_id,
                        visibility_override=visibility,
                        needed_for_date=needed_for_date,
                        needed_for_daypart_id=needed_for_daypart_id,
                    )
                    if added:
                        added_names.append(component["name"])
            return {
                "added": bool(added_names),
                "count": len(added_names),
                "names": added_names,
                "scheduled_count": len(scheduled_names),
                "scheduled_names": scheduled_names,
                "used_components": True,
            }
        return {
            "added": False,
            "count": 0,
            "names": [],
            "scheduled_count": 0,
            "scheduled_names": [],
            "used_components": True,
        }

    if item["availability_state"] == "home":
        return {
            "added": False,
            "count": 0,
            "names": [],
            "scheduled_count": 0,
            "scheduled_names": [],
            "used_components": False,
        }

    if needed_for_date and not should_activate_shopping_need(parse_plan_date(needed_for_date)):
        schedule_shopping_need(
            item_id=item_id,
            user_id=user_id,
            visibility=visibility,
            needed_for_date=needed_for_date,
            needed_for_daypart_id=needed_for_daypart_id,
            source_item_id=source_item_id,
        )
        return {
            "added": False,
            "count": 0,
            "names": [],
            "scheduled_count": 1,
            "scheduled_names": [item["name"]],
            "used_components": False,
        }

    added = add_to_shopping_list(
        item_id,
        user_id,
        visibility_override=visibility,
        needed_for_date=needed_for_date,
        needed_for_daypart_id=needed_for_daypart_id,
    )
    return {
        "added": added,
        "count": 1 if added else 0,
        "names": [item["name"]] if added else [],
        "scheduled_count": 0,
        "scheduled_names": [],
        "used_components": False,
    }


def sync_item_dayparts(item_id: int, daypart_ids: list[int]) -> None:
    get_db().execute("DELETE FROM item_dayparts WHERE item_id = ?", (item_id,))
    for daypart_id in daypart_ids:
        get_db().execute(
            "INSERT INTO item_dayparts (item_id, daypart_id) VALUES (?, ?)",
            (item_id, daypart_id),
        )


def sync_meal_components(meal_id: int, food_ids: list[int]) -> None:
    get_db().execute("DELETE FROM meal_components WHERE meal_item_id = ?", (meal_id,))
    visible_foods = {
        row["id"]
        for row in get_db().execute(
            f"""
            SELECT items.id
            FROM items
            WHERE items.kind = 'food' AND {visible_clause('items')}
            """,
            visible_params(),
        ).fetchall()
    }
    for food_id in food_ids:
        if food_id in visible_foods:
            get_db().execute(
                "INSERT INTO meal_components (meal_item_id, food_item_id) VALUES (?, ?)",
                (meal_id, food_id),
            )


def fetch_shopping_entries():
    rows = get_db().execute(
        f"""
        SELECT shopping_entries.*,
               items.name AS item_name,
               items.kind AS item_kind,
               items.photo_filename,
               items.availability_state,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username,
               dayparts.name AS needed_daypart_name
        FROM shopping_entries
        JOIN items ON items.id = shopping_entries.item_id
        LEFT JOIN users AS owner ON owner.id = shopping_entries.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        LEFT JOIN dayparts ON dayparts.id = shopping_entries.needed_for_daypart_id
        WHERE shopping_entries.is_checked = 0 AND {visible_clause('shopping_entries')}
        ORDER BY
            CASE shopping_entries.visibility WHEN 'shared' THEN 0 ELSE 1 END,
            shopping_entries.added_at DESC
        """,
        visible_params(),
    ).fetchall()
    entries = describe_records(rows)
    for entry in entries:
        if entry.get("needed_for_date"):
            try:
                parsed = datetime.strptime(entry["needed_for_date"], "%Y-%m-%d").date()
                entry["needed_for_label"] = parsed.strftime("%d.%m.%Y")
            except ValueError:
                entry["needed_for_label"] = entry["needed_for_date"]
        else:
            entry["needed_for_label"] = None
    return entries


def activate_due_shopping_needs(today: date | None = None) -> int:
    today = today or date.today()
    rows = get_db().execute(
        """
        SELECT shopping_needs.*,
               items.availability_state
        FROM shopping_needs
        JOIN items ON items.id = shopping_needs.item_id
        WHERE shopping_needs.household_id = ?
          AND shopping_needs.is_activated = 0
          AND shopping_needs.activation_date <= ?
        ORDER BY shopping_needs.activation_date, shopping_needs.needed_for_date
        """,
        (current_household_id(), today.isoformat()),
    ).fetchall()
    activated = 0
    for row in rows:
        if row["availability_state"] != "home":
            was_added = add_to_shopping_list(
                int(row["item_id"]),
                int(row["owner_user_id"] or g.user["id"]),
                visibility_override=row["visibility"],
                needed_for_date=row["needed_for_date"],
                needed_for_daypart_id=row["needed_for_daypart_id"],
            )
            activated += 1 if was_added else 0
        get_db().execute(
            "UPDATE shopping_needs SET is_activated = 1, activated_at = CURRENT_TIMESTAMP WHERE id = ?",
            (row["id"],),
        )
    if rows:
        get_db().commit()
    return activated


def fetch_upcoming_shopping_needs(limit: int | None = None) -> list[dict]:
    query = f"""
        SELECT shopping_needs.*,
               items.name AS item_name,
               items.kind AS item_kind,
               items.photo_filename,
               items.availability_state,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username,
               dayparts.name AS needed_daypart_name
        FROM shopping_needs
        JOIN items ON items.id = shopping_needs.item_id
        LEFT JOIN users AS owner ON owner.id = shopping_needs.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        LEFT JOIN dayparts ON dayparts.id = shopping_needs.needed_for_daypart_id
        WHERE shopping_needs.household_id = ?
          AND shopping_needs.is_activated = 0
          AND (shopping_needs.visibility = 'shared' OR shopping_needs.owner_user_id = ?)
          AND items.availability_state != 'home'
        ORDER BY shopping_needs.activation_date, shopping_needs.needed_for_date, LOWER(items.name)
    """
    params: list[object] = [current_household_id(), g.user["id"]]
    if limit:
        query += " LIMIT ?"
        params.append(limit)
    rows = get_db().execute(query, params).fetchall()
    entries = describe_records(rows)
    for entry in entries:
        try:
            entry["needed_for_label"] = datetime.strptime(entry["needed_for_date"], "%Y-%m-%d").date().strftime("%d.%m.%Y")
            entry["activation_label"] = datetime.strptime(entry["activation_date"], "%Y-%m-%d").date().strftime("%d.%m.%Y")
        except ValueError:
            entry["needed_for_label"] = entry["needed_for_date"]
            entry["activation_label"] = entry["activation_date"]
    return entries


def fetch_plan_entries_for_range(start_date: date, end_date: date):
    rows = get_db().execute(
        f"""
        SELECT plan_entries.*,
               items.name AS item_name,
               items.kind AS item_kind,
               items.photo_filename,
               items.availability_state,
               dayparts.name AS daypart_name,
               dayparts.slug AS daypart_slug,
               dayparts.sort_order,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username
        FROM plan_entries
        JOIN items ON items.id = plan_entries.item_id
        JOIN dayparts ON dayparts.id = plan_entries.daypart_id
        LEFT JOIN users AS owner ON owner.id = plan_entries.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        WHERE plan_date BETWEEN ? AND ? AND {visible_clause('plan_entries')}
        ORDER BY plan_date, dayparts.sort_order, items.name
        """,
        [start_date.isoformat(), end_date.isoformat(), *visible_params()],
    ).fetchall()
    grouped = defaultdict(list)
    for row in describe_records(rows):
        grouped[(row["plan_date"], row["daypart_id"])].append(row)
    return grouped


def fetch_day_plan_entries(selected_date: date):
    return fetch_plan_entries_for_range(selected_date, selected_date)


def fetch_recent_plan_items(daypart_id: int, limit: int = 6):
    rows = get_db().execute(
        f"""
        SELECT DISTINCT items.id,
               items.household_id,
               items.owner_user_id,
               items.target_user_id,
               items.visibility,
               items.name,
               items.kind,
               items.category,
               items.note,
               items.photo_filename,
               items.availability_state,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username
        FROM plan_entries
        JOIN items ON items.id = plan_entries.item_id
        LEFT JOIN users AS owner ON owner.id = items.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        WHERE plan_entries.daypart_id = ? AND {visible_clause('items')}
        ORDER BY plan_entries.created_at DESC
        LIMIT ?
        """,
        [daypart_id, *visible_params(), limit * 3],
    ).fetchall()
    return decorate_items(rows)


def fetch_plan_candidates(daypart_id: int, query: str | None = None):
    params = [daypart_id, *visible_params()]
    conditions = [visible_clause("items"), "items.availability_state != 'archived'"]
    if query:
        conditions.append("LOWER(items.name) LIKE ?")
        params.append(f"%{query.lower()}%")

    rows = get_db().execute(
        f"""
        SELECT items.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               target.display_name AS target_display_name,
               target.username AS target_username,
               EXISTS(
                   SELECT 1
                   FROM item_dayparts
                   WHERE item_dayparts.item_id = items.id AND item_dayparts.daypart_id = ?
               ) AS matches_daypart
        FROM items
        LEFT JOIN users AS owner ON owner.id = items.owner_user_id
        LEFT JOIN users AS target ON target.id = items.target_user_id
        WHERE {' AND '.join(conditions)}
        ORDER BY
            CASE items.availability_state WHEN 'home' THEN 0 WHEN 'idea' THEN 1 ELSE 2 END,
            matches_daypart DESC,
            CASE items.visibility WHEN 'shared' THEN 0 ELSE 1 END,
            LOWER(items.name)
        """,
        params,
    ).fetchall()
    return decorate_items(rows)


def fetch_home_food_ids() -> set[int]:
    rows = get_db().execute(
        f"""
        SELECT id
        FROM items
        WHERE kind = 'food' AND availability_state = 'home' AND {visible_clause('items')}
        """,
        visible_params(),
    ).fetchall()
    return {int(row["id"]) for row in rows}


def get_daypart_by_id(daypart_id: int):
    for daypart in get_dayparts():
        if int(daypart["id"]) == int(daypart_id):
            return daypart
    return None


def format_item_names(items: list[dict], limit: int = 3) -> str:
    return ", ".join(item["name"] for item in items[:limit])


def item_matches_daypart(item: dict, daypart_id: int | None) -> bool:
    if daypart_id is None:
        return True
    dayparts_meta = item.get("dayparts_meta") or []
    if not dayparts_meta:
        return True
    return any(int(daypart["id"]) == int(daypart_id) for daypart in dayparts_meta)


def normalized_component_signature(component_ids: list[int]) -> tuple[int, ...]:
    return tuple(sorted({int(component_id) for component_id in component_ids}))


def build_generated_meal_name(combo: list[dict], daypart_slug: str) -> str:
    names = [item["name"] for item in combo]
    if daypart_slug in {"breakfast", "morning-snack", "afternoon-snack", "late-snack"} and len(names) >= 2:
        return f"{names[0]} mit {', '.join(names[1:])}"
    if len(names) >= 2:
        return f"{names[0]} mit {', '.join(names[1:])}"
    return names[0]


def build_dynamic_meal_suggestions(home_foods: list[dict], daypart_slug: str, limit: int) -> list[dict]:
    builder_groups: dict[str, list[dict]] = defaultdict(list)
    for food in home_foods:
        for builder_key in food.get("builder_keys", ["neutral"]):
            builder_groups[builder_key].append(food)

    if daypart_slug in {"breakfast", "morning-snack", "afternoon-snack", "late-snack"}:
        target_patterns = [
            ("carb", "dairy", "fruit"),
            ("carb", "dairy", "nuts"),
            ("carb", "dairy", "seeds"),
            ("carb", "fruit", "dairy"),
        ]
        reasons = {
            ("carb", "dairy", "fruit"): "Passt gut zu Frühstück oder Snack",
            ("carb", "dairy", "nuts"): "Lässt sich gut für einen Snack vormerken",
            ("carb", "dairy", "seeds"): "Lässt sich gut für einen Snack vormerken",
            ("carb", "fruit", "dairy"): "Zuhause gut kombinierbar",
        }
    else:
        target_patterns = [
            ("protein", "carb", "veg"),
            ("protein", "carb"),
        ]
        reasons = {
            ("protein", "carb", "veg"): "Zuhause als vollständige Mahlzeit möglich",
            ("protein", "carb"): "Lässt sich leicht ergänzen",
        }

    suggestions: list[dict] = []
    seen_signatures: set[tuple[int, ...]] = set()

    for pattern in target_patterns:
        groups = [builder_groups.get(builder_key, []) for builder_key in pattern]
        if any(not group for group in groups):
            continue
        for combo in product(*groups):
            signature = normalized_component_signature([item["id"] for item in combo])
            if len(signature) != len(pattern) or signature in seen_signatures:
                continue
            seen_signatures.add(signature)
            combo_items = list(combo)
            suggestions.append(
                {
                    "title": build_generated_meal_name(combo_items, daypart_slug),
                    "reason": reasons.get(pattern, "Zuhause gut kombinierbar"),
                    "component_ids": [item["id"] for item in combo_items],
                    "existing_item_id": None,
                }
            )
            if len(suggestions) >= limit:
                return suggestions
    return suggestions


def build_home_recipe_suggestions(daypart_id: int | None = None, limit: int = 4) -> list[dict]:
    settings = get_user_settings()
    daypart_slug = (get_daypart_by_id(daypart_id)["slug"] if daypart_id and get_daypart_by_id(daypart_id) else "")
    home_foods = [
        item
        for item in fetch_items(kind="food", availability="home")
        if item_matches_daypart(item, daypart_id)
    ]
    home_food_ids = {item["id"] for item in home_foods}
    home_food_map = {int(item["id"]): item for item in home_foods}

    suggestions: list[dict] = []
    seen_signatures: set[tuple[int, ...]] = set()
    meals = [item for item in fetch_items(kind="meal") if item_matches_daypart(item, daypart_id)]
    for meal in meals:
        if meal["component_ids"] and all(component_id in home_food_ids for component_id in meal["component_ids"]):
            signature = normalized_component_signature(meal["component_ids"])
            if signature in seen_signatures:
                continue
            seen_signatures.add(signature)
            component_items = [home_food_map[component_id] for component_id in meal["component_ids"] if component_id in home_food_map]
            suggestions.append(
                {
                    "title": meal["name"],
                    "reason": "Zuhause vorhanden",
                    "component_ids": meal["component_ids"],
                    "existing_item_id": meal["id"],
                    "score": score_suggestion_components(component_items, daypart_slug=daypart_slug, settings=settings) + 40,
                }
            )

    for suggestion in build_dynamic_meal_suggestions(home_foods, daypart_slug, limit=limit * 2):
        signature = normalized_component_signature(suggestion["component_ids"])
        if signature in seen_signatures:
            continue
        seen_signatures.add(signature)
        component_items = [home_food_map[component_id] for component_id in suggestion["component_ids"] if component_id in home_food_map]
        suggestion["score"] = score_suggestion_components(component_items, daypart_slug=daypart_slug, settings=settings)
        suggestions.append(suggestion)

    deduped: list[dict] = []
    seen = set()
    ranked_suggestions = sorted(
        suggestions,
        key=lambda suggestion: (
            -int(suggestion.get("score", 0)),
            0 if suggestion.get("existing_item_id") else 1,
            suggestion["title"].lower(),
        ),
    )
    for suggestion in ranked_suggestions:
        if suggestion["title"] in seen:
            continue
        seen.add(suggestion["title"])
        deduped.append(suggestion)
        if len(deduped) >= limit:
            break
    return deduped


def build_balance_suggestion(daypart_id: int, item_ids: list[int]) -> dict | None:
    settings = get_user_settings()
    if not (settings.get("reminders_enabled") and settings.get("show_meal_balancing")):
        return None
    daypart = get_daypart_by_id(daypart_id)
    if not daypart or daypart["slug"] not in {"lunch", "dinner"}:
        return None
    builder_map = fetch_builder_keys_for_item_ids(item_ids)
    present = set()
    for keys in builder_map.values():
        present.update(keys)
    target_order = ["protein", "carb", "veg"]
    missing = [key for key in target_order if key not in present]
    if not missing:
        return None
    first_missing = missing[0]
    home_matches = [
        item for item in fetch_items(kind="food", availability="home", daypart_id=daypart_id)
        if first_missing in item.get("builder_keys", [])
    ]
    home_matches = sorted(
        home_matches,
        key=lambda item: -score_suggestion_components([item], daypart["slug"], settings),
    )
    text_map = {
        "protein": "Dazu könnte noch eine Proteinquelle gut passen.",
        "carb": "Das lässt sich gut mit einer Kohlenhydratquelle ergänzen.",
        "veg": "Dazu könnte noch etwas Gemüse gut passen.",
    }
    return {
        "text": text_map.get(first_missing, "Dazu könnte noch etwas Kleines gut passen."),
        "items": home_matches[:3],
    }


def build_daypart_suggestions(daypart_id: int) -> list[dict]:
    settings = get_user_settings()
    if not settings.get("suggest_home_for_today"):
        return []
    suggestions = build_home_recipe_suggestions(daypart_id, limit=3)
    if suggestions:
        return suggestions

    archived_items = fetch_items(availability="archived", include_archived=True, daypart_id=daypart_id)
    return [
        {
            "title": item["name"],
            "reason": "Für später vormerken",
            "component_ids": [],
            "existing_item_id": item["id"] if item["kind"] == "meal" else None,
        }
        for item in archived_items[:2]
    ]


def build_dashboard_hints(today: date) -> list[str]:
    settings = get_user_settings()
    if not settings.get("reminders_enabled"):
        return []

    hints: list[str] = []
    tomorrow = today + timedelta(days=1)
    household_settings = get_household_settings()

    if settings.get("remind_tomorrow_if_sparse"):
        breakfast = get_db().execute(
            f"""
            SELECT COUNT(*) AS count
            FROM plan_entries
            JOIN dayparts ON dayparts.id = plan_entries.daypart_id
            WHERE plan_entries.plan_date = ? AND dayparts.slug = 'breakfast' AND {visible_clause('plan_entries')}
            """,
            [tomorrow.isoformat(), *visible_params()],
        ).fetchone()
        if int(breakfast["count"]) == 0:
            hints.append("Für morgen ist noch kein Frühstück eingeplant.")

    if settings.get("suggest_home_for_today"):
        dinner_home = get_db().execute(
            f"""
            SELECT COUNT(*) AS count
            FROM items
            JOIN item_dayparts ON item_dayparts.item_id = items.id
            JOIN dayparts ON dayparts.id = item_dayparts.daypart_id
            WHERE items.availability_state = 'home'
              AND dayparts.slug = 'dinner'
              AND {visible_clause('items')}
            """,
            visible_params(),
        ).fetchone()
        if int(dinner_home["count"]) > 0:
            hints.append("Zuhause ist bereits etwas da, das gut zu Abendessen passt.")

    if settings.get("remind_before_shopping") and (today + timedelta(days=1)).weekday() == household_settings["shopping_weekday"]:
        upcoming = fetch_upcoming_shopping_needs(limit=3)
        if upcoming:
            hints.append("Für den nächsten Einkauf sind schon ein paar Dinge vorgemerkt.")

    if settings.get("remind_nuts"):
        nut_items = [item for item in fetch_items(kind="food", availability="home") if {"nuts", "seeds"} & set(item.get("builder_keys", []))]
        if nut_items:
            hints.append("Heute schon an Nüsse gedacht?")

    if settings.get("suggest_templates"):
        old_template = get_db().execute(
            f"""
            SELECT name
            FROM day_templates
            WHERE {visible_clause('day_templates')}
              AND last_used_at IS NOT NULL
              AND DATE(last_used_at) <= DATE('now', '-21 day')
            ORDER BY last_used_at ASC
            LIMIT 1
            """,
            visible_params(),
        ).fetchone()
        if old_template:
            hints.append(f"„{old_template['name']}“ könnte diese Woche wieder passen.")
    return hints[:4]


def build_setup_checklist(today: date) -> list[dict]:
    total_items = int(
        get_db().execute(
            f"SELECT COUNT(*) AS count FROM items WHERE {visible_clause('items')}",
            visible_params(),
        ).fetchone()["count"]
    )
    meal_count = int(
        get_db().execute(
            f"SELECT COUNT(*) AS count FROM items WHERE kind = 'meal' AND {visible_clause('items')}",
            visible_params(),
        ).fetchone()["count"]
    )
    week_end = today + timedelta(days=6)
    plan_count = int(
        get_db().execute(
            f"""
            SELECT COUNT(*) AS count
            FROM plan_entries
            WHERE plan_date BETWEEN ? AND ? AND {visible_clause('plan_entries')}
            """,
            [today.isoformat(), week_end.isoformat(), *visible_params()],
        ).fetchone()["count"]
    )
    template_count = int(
        get_db().execute(
            f"SELECT COUNT(*) AS count FROM day_templates WHERE {visible_clause('day_templates')}",
            visible_params(),
        ).fetchone()["count"]
    )

    checklist = []
    if total_items == 0:
        checklist.append(
            {
                "title": "Fang mit einem ersten Lebensmittel an",
                "text": "Ein kleines Frühstück, ein Snack oder etwas für zuhause reicht völlig für den Start.",
                "url": url_for("main.item_create", kind="food"),
                "label": "Lebensmittel anlegen",
            }
        )
    if total_items > 0 and meal_count == 0:
        checklist.append(
            {
                "title": "Lege eine erste Mahlzeitenidee an",
                "text": "Einfach zwei oder drei vertraute Dinge zusammenklicken und für später merken.",
                "url": url_for("main.item_create", kind="meal"),
                "label": "Mahlzeit anlegen",
            }
        )
    if plan_count == 0:
        checklist.append(
            {
                "title": "Plane einen ruhigen ersten Tag",
                "text": "Mit einem kleinen Eintrag für Frühstück oder Abendessen fühlt sich die Woche sofort greifbarer an.",
                "url": url_for("main.planner_day", date=today.isoformat()),
                "label": "Tag öffnen",
            }
        )
    if total_items > 0 and template_count == 0:
        checklist.append(
            {
                "title": "Merke dir einen gelungenen Tag als Vorlage",
                "text": "So wird Wiederverwendung später noch leichter.",
                "url": url_for("main.template_library"),
                "label": "Vorlagen ansehen",
            }
        )
    return checklist[:3]


def build_day_hints(selected_date: date) -> list[str]:
    settings = get_user_settings()
    if not settings.get("reminders_enabled"):
        return []

    hints: list[str] = []
    if settings.get("remind_tomorrow_if_sparse"):
        breakfast_count = get_db().execute(
            f"""
            SELECT COUNT(*) AS count
            FROM plan_entries
            JOIN dayparts ON dayparts.id = plan_entries.daypart_id
            WHERE plan_entries.plan_date = ? AND dayparts.slug = 'breakfast' AND {visible_clause('plan_entries')}
            """,
            [selected_date.isoformat(), *visible_params()],
        ).fetchone()
        if int(breakfast_count["count"]) == 0:
            hints.append("Für diesen Tag ist noch kein Frühstück eingeplant.")

    if settings.get("remind_small_snack"):
        afternoon_options = get_db().execute(
            f"""
            SELECT COUNT(*) AS count
            FROM items
            JOIN item_dayparts ON item_dayparts.item_id = items.id
            JOIN dayparts ON dayparts.id = item_dayparts.daypart_id
            WHERE items.availability_state != 'archived'
              AND dayparts.slug = 'afternoon-snack'
              AND {visible_clause('items')}
            """,
            visible_params(),
        ).fetchone()
        if int(afternoon_options["count"]) < 2:
            hints.append("Für den Nachmittag wäre noch etwas Kleines möglich.")

    if settings.get("show_planned_not_shopped"):
        pending_for_day = fetch_upcoming_shopping_needs(limit=20)
        pending_for_day = [entry for entry in pending_for_day if entry["needed_for_date"] == selected_date.isoformat()]
        if pending_for_day:
            hints.append("Ein paar Dinge sind für diesen Tag schon vorgemerkt, aber noch nicht auf der Einkaufsliste.")
    return hints[:4]


def build_week_hints(week_start: date) -> list[str]:
    settings = get_user_settings()
    if not settings.get("reminders_enabled"):
        return []

    hints: list[str] = []
    week_end = week_start + timedelta(days=6)
    if settings.get("remind_week_if_sparse"):
        breakfast_days = get_db().execute(
            f"""
            SELECT COUNT(DISTINCT plan_entries.plan_date) AS count
            FROM plan_entries
            JOIN dayparts ON dayparts.id = plan_entries.daypart_id
            WHERE plan_entries.plan_date BETWEEN ? AND ?
              AND dayparts.slug = 'breakfast'
              AND {visible_clause('plan_entries')}
            """,
            [week_start.isoformat(), week_end.isoformat(), *visible_params()],
        ).fetchone()
        missing_breakfasts = 7 - int(breakfast_days["count"])
        if missing_breakfasts > 0:
            hints.append(f"Für diese Woche sind noch {missing_breakfasts} Tage ohne Frühstück eingeplant.")

    if settings.get("show_missing_for_upcoming_week"):
        due_entries = [entry for entry in fetch_upcoming_shopping_needs(limit=20) if week_start.isoformat() <= entry["needed_for_date"] <= week_end.isoformat()]
        if due_entries:
            hints.append("Für diese Woche fehlt noch etwas, das später zum Einkauf dazukommen kann.")

    if settings.get("remind_on_shopping_day") and week_start.weekday() <= get_household_settings()["shopping_weekday"] <= week_end.weekday():
        hints.append("Der Einkaufstag liegt in dieser Woche schon bereit im Blick.")
    return hints[:4]


def build_home_sections(items: list[dict], dayparts: list, selected_daypart_id: int | None):
    sections = []
    if selected_daypart_id:
        selected_daypart = next((daypart for daypart in dayparts if daypart["id"] == selected_daypart_id), None)
        matching_items = [item for item in items if any(dp["id"] == selected_daypart_id for dp in item["dayparts_meta"])]
        sections.append(
            {
                "title": selected_daypart["name"] if selected_daypart else "Ausgewählte Tageszeit",
                "items": matching_items,
            }
        )
        return sections

    for daypart in dayparts:
        matching_items = [item for item in items if any(dp["id"] == daypart["id"] for dp in item["dayparts_meta"])]
        sections.append({"title": daypart["name"], "items": matching_items})

    anytime_items = [item for item in items if not item["dayparts_meta"]]
    if anytime_items:
        sections.append({"title": "Ohne feste Tageszeit", "items": anytime_items})
    return sections


def dedupe_items(items: list[dict], limit: int = 6) -> list[dict]:
    result = []
    seen_ids = set()
    for item in items:
        if item["id"] in seen_ids:
            continue
        seen_ids.add(item["id"])
        result.append(item)
        if len(result) >= limit:
            break
    return result


def build_selected_quick_action(
    *,
    daypart_id: int,
    selected_item_id: int | None,
    selected_meal_name: str,
    selected_component_ids: list[int],
    candidates: list[dict],
) -> dict | None:
    if selected_item_id:
        selected_item = next((item for item in candidates if int(item["id"]) == int(selected_item_id)), None)
        if selected_item is None:
            try:
                selected_item = get_item(selected_item_id)
            except ValueError:
                selected_item = None
        if selected_item is not None:
            return {
                "type": "existing",
                "title": selected_item["name"],
                "subtitle": "Bereit zum Eintragen",
                "item_id": int(selected_item["id"]),
                "visibility": selected_item["visibility"],
                "daypart_id": daypart_id,
            }

    if selected_meal_name and selected_component_ids:
        return {
            "type": "generated",
            "title": selected_meal_name,
            "subtitle": "Vorgeschlagen aus dem, was zuhause da ist",
            "component_ids": selected_component_ids,
            "visibility": "shared",
            "daypart_id": daypart_id,
        }

    return None


def build_day_planner_sections(
    selected_date: date,
    selected_item_id: int | None,
    selected_daypart_id: int | None,
    selected_meal_name: str = "",
    selected_component_ids: list[int] | None = None,
):
    selected_component_ids = selected_component_ids or []
    sections = []
    day_entries = fetch_day_plan_entries(selected_date)
    for daypart in get_dayparts():
        candidates = fetch_plan_candidates(daypart["id"])
        entries = day_entries.get((selected_date.isoformat(), daypart["id"]), [])
        meal_candidates = dedupe_items(
            [item for item in candidates if item["kind"] == "meal" and item["availability_state"] == "home"]
            + [item for item in candidates if item["kind"] == "meal"],
            limit=6,
        )
        food_candidates = dedupe_items(
            [item for item in candidates if item["kind"] == "food" and item["availability_state"] == "home"]
            + fetch_recent_plan_items(daypart["id"])
            + [item for item in candidates if item["kind"] == "food"],
            limit=20,
        )
        entry_item_ids = [int(entry["item_id"]) for entry in entries]
        sections.append(
            {
                "daypart": daypart,
                "entries": entries,
                "candidates": candidates,
                "meal_candidates": meal_candidates,
                "food_candidates": food_candidates,
                "recipe_suggestions": build_home_recipe_suggestions(int(daypart["id"]), limit=3),
                "suggestions": build_daypart_suggestions(daypart["id"]),
                "balance_suggestion": build_balance_suggestion(int(daypart["id"]), entry_item_ids),
                "selected_item_id": selected_item_id if selected_daypart_id == daypart["id"] else None,
                "selected_quick_action": build_selected_quick_action(
                    daypart_id=int(daypart["id"]),
                    selected_item_id=selected_item_id if selected_daypart_id == daypart["id"] else None,
                    selected_meal_name=selected_meal_name if selected_daypart_id == daypart["id"] else "",
                    selected_component_ids=selected_component_ids if selected_daypart_id == daypart["id"] else [],
                    candidates=candidates,
                ),
                "is_open": selected_daypart_id == daypart["id"],
                "summary_items": [entry["item_name"] for entry in entries][:2],
                "default_visibility": "shared",
            }
        )
    return sections


def build_template_day_sections(selected_map: dict[int, list[int]] | None = None):
    selected_map = selected_map or {}
    sections = []
    for daypart in get_dayparts():
        candidates = fetch_plan_candidates(int(daypart["id"]))
        quick_items = dedupe_items(
            [item for item in candidates if item["availability_state"] == "home"] + candidates,
            limit=10,
        )
        quick_ids = {item["id"] for item in quick_items}
        sections.append(
            {
                "daypart": daypart,
                "candidates": candidates,
                "quick_items": quick_items,
                "list_items": [item for item in candidates if item["id"] not in quick_ids],
                "selected_ids": selected_map.get(int(daypart["id"]), []),
            }
        )
    return sections


def fetch_week_cards(week_start: date):
    days = [week_start + timedelta(days=index) for index in range(7)]
    grouped_entries = fetch_plan_entries_for_range(week_start, week_start + timedelta(days=6))
    cards = []
    for current_day in days:
        filled_dayparts = []
        planned_count = 0
        preview_items = []
        slots = []
        for daypart in get_dayparts():
            slot_entries = grouped_entries.get((current_day.isoformat(), daypart["id"]), [])
            slots.append({"daypart": dict(daypart), "entries": slot_entries})
            if slot_entries:
                filled_dayparts.append({"id": daypart["id"], "name": daypart["name"], "count": len(slot_entries)})
                planned_count += len(slot_entries)
                preview_items.extend(entry["item_name"] for entry in slot_entries[:2])
        cards.append(
            {
                "date": current_day,
                "filled_dayparts": filled_dayparts,
                "planned_count": planned_count,
                "preview_items": preview_items[:4],
                "slots": slots,
            }
        )
    return cards


def count_visible_items(availability_state: str) -> int:
    row = get_db().execute(
        f"SELECT COUNT(*) AS count FROM items WHERE availability_state = ? AND {visible_clause('items')}",
        [availability_state, *visible_params()],
    ).fetchone()
    return int(row["count"])


def fetch_day_templates(query: str | None = None, visibility: str | None = None) -> list[dict]:
    conditions = [visible_clause("day_templates")]
    params = visible_params()
    if query:
        conditions.append("LOWER(day_templates.name) LIKE ?")
        params.append(f"%{query.lower()}%")
    if visibility:
        conditions.append("day_templates.visibility = ?")
        params.append(visibility)
    rows = get_db().execute(
        f"""
        SELECT day_templates.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               (
                   SELECT COUNT(*)
                   FROM day_template_entries
                   WHERE day_template_entries.day_template_id = day_templates.id
               ) AS entry_count
        FROM day_templates
        LEFT JOIN users AS owner ON owner.id = day_templates.owner_user_id
        WHERE {' AND '.join(conditions)}
        ORDER BY LOWER(day_templates.name)
        """,
        params,
    ).fetchall()
    return [describe_template_record(dict(row)) for row in rows]


def get_day_template(template_id: int) -> dict:
    row = get_db().execute(
        f"""
        SELECT day_templates.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username
        FROM day_templates
        LEFT JOIN users AS owner ON owner.id = day_templates.owner_user_id
        WHERE day_templates.id = ? AND {visible_clause('day_templates')}
        """,
        [template_id, *visible_params()],
    ).fetchone()
    if row is None:
        raise ValueError("Die Tagesvorlage wurde nicht gefunden.")
    return describe_template_record(dict(row))


def get_day_template_selected_map(template_id: int) -> dict[int, list[int]]:
    rows = get_db().execute(
        """
        SELECT daypart_id, item_id
        FROM day_template_entries
        WHERE day_template_id = ?
        ORDER BY sort_order, id
        """,
        (template_id,),
    ).fetchall()
    grouped: dict[int, list[int]] = defaultdict(list)
    for row in rows:
        grouped[int(row["daypart_id"])].append(int(row["item_id"]))
    return grouped


def sync_day_template_entries(template_id: int, selected_map: dict[int, list[int]]) -> None:
    get_db().execute("DELETE FROM day_template_entries WHERE day_template_id = ?", (template_id,))
    for daypart in get_dayparts():
        for sort_order, item_id in enumerate(selected_map.get(int(daypart["id"]), []), start=10):
            get_db().execute(
                """
                INSERT INTO day_template_entries (day_template_id, daypart_id, item_id, sort_order)
                VALUES (?, ?, ?, ?)
                """,
                (template_id, daypart["id"], item_id, sort_order),
            )


def day_template_form_data(template: dict | None = None, source_date: date | None = None) -> dict:
    selected_map: dict[int, list[int]] = defaultdict(list)
    if template:
        selected_map.update(get_day_template_selected_map(template["id"]))
    elif source_date:
        for (plan_date_key, daypart_id), entries in fetch_day_plan_entries(source_date).items():
            if plan_date_key == source_date.isoformat():
                selected_map[int(daypart_id)] = [int(entry["item_id"]) for entry in entries]

    form_data: dict[str, object] = {
        "name": template["name"] if template else "",
        "description": template["description"] if template else "",
        "visibility": template["visibility"] if template else "shared",
        "selected_map": {key: value[:] for key, value in selected_map.items()},
    }
    return form_data


def extract_day_template_form_data(existing: dict | None = None) -> dict:
    form_data = existing or {}
    selected_map: dict[int, list[int]] = {}
    for daypart in get_dayparts():
        selected_map[int(daypart["id"])] = [
            int(value)
            for value in request.form.getlist(f"daypart_{daypart['id']}_item_ids")
            if value.isdigit()
        ]
    form_data.update(
        {
            "name": request.form.get("name", "").strip(),
            "description": request.form.get("description", "").strip(),
            "visibility": normalize_visibility(request.form.get("visibility"), form_data.get("visibility", "shared")),
            "selected_map": selected_map,
        }
    )
    return form_data


def apply_day_template(template_id: int, selected_date: date) -> int:
    template = get_day_template(template_id)
    entries_map = get_day_template_selected_map(template_id)
    inserted = 0
    for daypart_id, item_ids in entries_map.items():
        for item_id in item_ids:
            existing = get_db().execute(
                """
                SELECT id
                FROM plan_entries
                WHERE plan_date = ? AND daypart_id = ? AND item_id = ? AND visibility = ?
                """,
                (selected_date.isoformat(), daypart_id, item_id, template["visibility"]),
            ).fetchone()
            if existing:
                continue
            get_db().execute(
                """
                INSERT INTO plan_entries (household_id, owner_user_id, visibility, plan_date, daypart_id, item_id, created_by)
                VALUES (?, ?, ?, ?, ?, ?, ?)
                """,
                (
                    current_household_id(),
                    g.user["id"],
                    template["visibility"],
                    selected_date.isoformat(),
                    daypart_id,
                    item_id,
                    g.user["id"],
                ),
            )
            insert_result = ensure_item_or_missing_components_are_shopped(
                item_id,
                g.user["id"],
                template["visibility"],
                needed_for_date=selected_date.isoformat(),
                needed_for_daypart_id=daypart_id,
                source_item_id=item_id,
            )
            inserted += 1
        get_db().commit()
    get_db().execute(
        "UPDATE day_templates SET last_used_at = CURRENT_TIMESTAMP WHERE id = ?",
        (template_id,),
    )
    get_db().commit()
    return inserted


def create_day_template_snapshot(name: str, description: str, visibility: str, source_date: date) -> int | None:
    selected_map = day_template_form_data(source_date=source_date)["selected_map"]
    if not any(selected_map.values()):
        return None
    cursor = get_db().execute(
        """
        INSERT INTO day_templates (household_id, owner_user_id, visibility, name, description)
        VALUES (?, ?, ?, ?, ?)
        """,
        (current_household_id(), g.user["id"], visibility, name, description),
    )
    template_id = int(cursor.lastrowid)
    sync_day_template_entries(template_id, selected_map)
    return template_id


def fetch_week_templates(query: str | None = None, visibility: str | None = None) -> list[dict]:
    conditions = [visible_clause("week_templates")]
    params = visible_params()
    if query:
        conditions.append("LOWER(week_templates.name) LIKE ?")
        params.append(f"%{query.lower()}%")
    if visibility:
        conditions.append("week_templates.visibility = ?")
        params.append(visibility)
    rows = get_db().execute(
        f"""
        SELECT week_templates.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               (
                   SELECT COUNT(*)
                   FROM week_template_days
                   WHERE week_template_days.week_template_id = week_templates.id
               ) AS day_count
        FROM week_templates
        LEFT JOIN users AS owner ON owner.id = week_templates.owner_user_id
        WHERE {' AND '.join(conditions)}
        ORDER BY LOWER(week_templates.name)
        """,
        params,
    ).fetchall()
    return [describe_template_record(dict(row)) for row in rows]


def get_week_template(template_id: int) -> dict:
    row = get_db().execute(
        f"""
        SELECT week_templates.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username
        FROM week_templates
        LEFT JOIN users AS owner ON owner.id = week_templates.owner_user_id
        WHERE week_templates.id = ? AND {visible_clause('week_templates')}
        """,
        [template_id, *visible_params()],
    ).fetchone()
    if row is None:
        raise ValueError("Die Wochenvorlage wurde nicht gefunden.")
    return describe_template_record(dict(row))


def get_week_template_selected_map(template_id: int) -> dict[int, int]:
    rows = get_db().execute(
        """
        SELECT weekday_index, day_template_id
        FROM week_template_days
        WHERE week_template_id = ?
        ORDER BY weekday_index
        """,
        (template_id,),
    ).fetchall()
    return {int(row["weekday_index"]): int(row["day_template_id"]) for row in rows}


def week_template_form_data(template: dict | None = None, source_week: date | None = None) -> dict:
    selected_map = get_week_template_selected_map(template["id"]) if template else {}
    source_days = {}
    if source_week:
        for weekday_index in range(7):
            source_days[weekday_index] = fetch_day_plan_entries(source_week + timedelta(days=weekday_index))
    return {
        "name": template["name"] if template else "",
        "description": template["description"] if template else "",
        "visibility": template["visibility"] if template else "shared",
        "selected_map": selected_map,
        "source_week": source_week.isoformat() if source_week else "",
        "copy_from_source": {
            index: bool(source_days.get(index))
            for index in range(7)
        },
    }


def extract_week_template_form_data(existing: dict | None = None) -> dict:
    form_data = existing or {}
    selected_map: dict[int, int | None] = {}
    copy_from_source: dict[int, bool] = {}
    for weekday_index in range(7):
        raw_value = request.form.get(f"weekday_{weekday_index}_day_template_id", "").strip()
        selected_map[weekday_index] = int(raw_value) if raw_value.isdigit() else None
        copy_from_source[weekday_index] = request.form.get(f"weekday_{weekday_index}_copy_source") == "1"
    form_data.update(
        {
            "name": request.form.get("name", "").strip(),
            "description": request.form.get("description", "").strip(),
            "visibility": normalize_visibility(request.form.get("visibility"), form_data.get("visibility", "shared")),
            "selected_map": selected_map,
            "source_week": request.form.get("source_week", "").strip(),
            "copy_from_source": copy_from_source,
        }
    )
    return form_data


def sync_week_template_days(template_id: int, selected_map: dict[int, int | None]) -> None:
    get_db().execute("DELETE FROM week_template_days WHERE week_template_id = ?", (template_id,))
    for weekday_index, day_template_id in selected_map.items():
        if day_template_id:
            get_db().execute(
                """
                INSERT INTO week_template_days (week_template_id, weekday_index, day_template_id)
                VALUES (?, ?, ?)
                """,
                (template_id, weekday_index, day_template_id),
            )


def apply_week_template(template_id: int, week_start: date) -> int:
    selected_map = get_week_template_selected_map(template_id)
    inserted = 0
    for weekday_index, day_template_id in selected_map.items():
        inserted += apply_day_template(day_template_id, week_start + timedelta(days=weekday_index))
    get_db().execute(
        "UPDATE week_templates SET last_used_at = CURRENT_TIMESTAMP WHERE id = ?",
        (template_id,),
    )
    get_db().commit()
    return inserted


def fetch_item_sets(query: str | None = None, visibility: str | None = None) -> list[dict]:
    conditions = [visible_clause("item_sets")]
    params = visible_params()
    if query:
        conditions.append("LOWER(item_sets.name) LIKE ?")
        params.append(f"%{query.lower()}%")
    if visibility:
        conditions.append("item_sets.visibility = ?")
        params.append(visibility)
    rows = get_db().execute(
        f"""
        SELECT item_sets.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username,
               (
                   SELECT COUNT(*)
                   FROM item_set_items
                   WHERE item_set_items.item_set_id = item_sets.id
               ) AS item_count
        FROM item_sets
        LEFT JOIN users AS owner ON owner.id = item_sets.owner_user_id
        WHERE {' AND '.join(conditions)}
        ORDER BY LOWER(item_sets.name)
        """,
        params,
    ).fetchall()
    return [describe_template_record(dict(row)) for row in rows]


def get_item_set(set_id: int) -> dict:
    row = get_db().execute(
        f"""
        SELECT item_sets.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username
        FROM item_sets
        LEFT JOIN users AS owner ON owner.id = item_sets.owner_user_id
        WHERE item_sets.id = ? AND {visible_clause('item_sets')}
        """,
        [set_id, *visible_params()],
    ).fetchone()
    if row is None:
        raise ValueError("Das Paket wurde nicht gefunden.")
    return describe_template_record(dict(row))


def get_item_set_selected_ids(set_id: int) -> list[int]:
    rows = get_db().execute(
        """
        SELECT item_id
        FROM item_set_items
        WHERE item_set_id = ?
        ORDER BY sort_order, id
        """,
        (set_id,),
    ).fetchall()
    return [int(row["item_id"]) for row in rows]


def sync_item_set_items(set_id: int, item_ids: list[int]) -> None:
    get_db().execute("DELETE FROM item_set_items WHERE item_set_id = ?", (set_id,))
    for sort_order, item_id in enumerate(item_ids, start=10):
        get_db().execute(
            """
            INSERT OR IGNORE INTO item_set_items (item_set_id, item_id, sort_order)
            VALUES (?, ?, ?)
            """,
            (set_id, item_id, sort_order),
        )


def extract_item_set_form_data(existing: dict | None = None) -> dict:
    form_data = existing or {}
    form_data.update(
        {
            "name": request.form.get("name", "").strip(),
            "description": request.form.get("description", "").strip(),
            "visibility": normalize_visibility(request.form.get("visibility"), form_data.get("visibility", "shared")),
            "item_ids": [int(value) for value in request.form.getlist("item_ids") if value.isdigit()],
            "item_search": request.form.get("item_search", "").strip(),
        }
    )
    return form_data


def apply_item_set_to_shopping(set_id: int) -> dict:
    item_set = get_item_set(set_id)
    selected_ids = get_item_set_selected_ids(set_id)
    added_names: list[str] = []
    for item_id in selected_ids:
        result = ensure_item_or_missing_components_are_shopped(
            item_id,
            g.user["id"],
            item_set["visibility"],
        )
        added_names.extend(result["names"])
    get_db().execute(
        "UPDATE item_sets SET last_used_at = CURRENT_TIMESTAMP WHERE id = ?",
        (set_id,),
    )
    get_db().commit()
    return {"count": len(added_names), "names": added_names}


def render_item_form(kind: str, *, item: dict | None, form_data: dict):
    food_search = form_data.get("food_search") or None
    foods = fetch_food_options(query=food_search if kind == "meal" else None)
    return render_template(
        "items/form.html",
        kind=kind,
        item=item,
        dayparts=get_dayparts(),
        food_groups=group_items_by_availability(foods),
        categories=get_category_options(
            form_data.get("category") or form_data.get("quick_food_category")
        ),
        form_data=form_data,
        energy_density_options=ENERGY_DENSITY_OPTIONS,
        visibility_options=VISIBILITY_FORM_OPTIONS,
        target_user_options=get_target_user_options(),
    )


def create_or_get_generated_meal(
    *,
    name: str,
    component_ids: list[int],
    daypart_id: int,
    visibility: str,
) -> int:
    normalized_ids = normalized_component_signature(component_ids)
    existing_meals = [
        item
        for item in fetch_items(kind="meal")
        if normalized_component_signature(item.get("component_ids", [])) == normalized_ids
    ]
    if existing_meals:
        meal_id = int(existing_meals[0]["id"])
        current_dayparts = get_item_daypart_ids(meal_id)
        if daypart_id not in current_dayparts:
            sync_item_dayparts(meal_id, current_dayparts + [daypart_id])
            get_db().execute(
                """
                UPDATE items
                SET updated_by = ?, updated_at = CURRENT_TIMESTAMP
                WHERE id = ?
                """,
                (g.user["id"], meal_id),
            )
            get_db().commit()
        return meal_id

    existing = get_db().execute(
        f"""
        SELECT items.id
        FROM items
        WHERE items.kind = 'meal' AND LOWER(items.name) = LOWER(?) AND {visible_clause('items')}
        ORDER BY items.id
        LIMIT 1
        """,
        [name, *visible_params()],
    ).fetchone()
    if existing:
        meal_id = int(existing["id"])
        sync_meal_components(meal_id, list(normalized_ids))
        current_dayparts = get_item_daypart_ids(meal_id)
        if daypart_id not in current_dayparts:
            sync_item_dayparts(meal_id, current_dayparts + [daypart_id])
        get_db().execute(
            """
            UPDATE items
            SET updated_by = ?, updated_at = CURRENT_TIMESTAMP
            WHERE id = ?
            """,
            (g.user["id"], meal_id),
        )
        get_db().commit()
        return meal_id

    cursor = get_db().execute(
        """
        INSERT INTO items (
            household_id, owner_user_id, visibility, kind, name, category, created_by, updated_by
        )
        VALUES (?, ?, ?, 'meal', ?, ?, ?, ?)
        """,
        (
            current_household_id(),
            g.user["id"],
            visibility,
            name,
            "Kleines Essen" if get_daypart_by_id(daypart_id)["slug"] in {"breakfast", "morning-snack", "afternoon-snack", "late-snack"} else "Warmes",
            g.user["id"],
            g.user["id"],
        ),
    )
    meal_id = int(cursor.lastrowid)
    sync_item_dayparts(meal_id, [daypart_id])
    sync_meal_components(meal_id, list(normalized_ids))
    get_db().commit()
    return meal_id


def insert_plan_entry(*, item_id: int, daypart_id: int, plan_date: date, visibility: str, note: str = "") -> dict:
    get_db().execute(
        """
        INSERT INTO plan_entries (household_id, owner_user_id, visibility, plan_date, daypart_id, item_id, note, created_by)
        VALUES (?, ?, ?, ?, ?, ?, ?, ?)
        """,
        (
            current_household_id(),
            g.user["id"],
            visibility,
            plan_date.isoformat(),
            daypart_id,
            item_id,
            note,
            g.user["id"],
        ),
    )
    get_db().commit()
    return ensure_item_or_missing_components_are_shopped(
        item_id,
        g.user["id"],
        visibility,
        needed_for_date=plan_date.isoformat(),
        needed_for_daypart_id=daypart_id,
        source_item_id=item_id,
    )


def planner_template_options():
    return fetch_day_templates()


@main_bp.get("/")
@login_required
def dashboard():
    today = date.today()
    home_count = count_visible_items("home")
    archive_count = count_visible_items("archived")
    shopping_count = get_db().execute(
        f"SELECT COUNT(*) AS count FROM shopping_entries WHERE is_checked = 0 AND {visible_clause('shopping_entries')}",
        visible_params(),
    ).fetchone()["count"]
    today_entries = []
    for entries in fetch_day_plan_entries(today).values():
        today_entries.extend(entries)
    today_entries.sort(key=lambda entry: (entry["sort_order"], entry["item_name"].lower()))
    week_cards = fetch_week_cards(today - timedelta(days=today.weekday()))
    home_items = fetch_items(availability="home")
    return render_template(
        "dashboard.html",
        home_count=home_count,
        shopping_count=shopping_count,
        archive_count=archive_count,
        today_entries=today_entries,
        home_items=home_items[:8],
        today=today,
        week_cards=week_cards[:3],
        dashboard_hints=build_dashboard_hints(today),
        recipe_suggestions=build_home_recipe_suggestions(limit=4),
        upcoming_entries=fetch_upcoming_shopping_needs(limit=4),
        day_templates=fetch_day_templates()[:3],
        week_templates=fetch_week_templates()[:3],
        setup_checklist=build_setup_checklist(today),
    )


@main_bp.get("/templates")
@login_required
def template_library():
    query = request.args.get("q", "").strip()
    selected_visibility = request.args.get("visibility", "").strip()
    visibility = selected_visibility or None
    day_templates = fetch_day_templates(query=query or None, visibility=visibility)
    week_templates = fetch_week_templates(query=query or None, visibility=visibility)
    item_sets = fetch_item_sets(query=query or None, visibility=visibility)
    template_hints = build_dashboard_hints(date.today())
    return render_template(
        "library/index.html",
        query=query,
        selected_visibility=selected_visibility,
        visibility_options=VISIBILITY_FILTER_OPTIONS,
        day_templates=day_templates,
        week_templates=week_templates,
        item_sets=item_sets,
        template_hints=template_hints,
    )


@main_bp.route("/templates/day/new", methods=("GET", "POST"))
@login_required
def day_template_create():
    source_date = parse_plan_date(request.values.get("source_date"), fallback=None) if request.values.get("source_date") else None
    form_data = day_template_form_data(source_date=source_date)
    if request.method == "POST":
        form_data = extract_day_template_form_data(form_data)
        if not form_data["name"]:
            flash("Bitte einen Namen für die Tagesvorlage eintragen.", "error")
        else:
            cursor = get_db().execute(
                """
                INSERT INTO day_templates (household_id, owner_user_id, visibility, name, description)
                VALUES (?, ?, ?, ?, ?)
                """,
                (
                    current_household_id(),
                    g.user["id"],
                    form_data["visibility"],
                    form_data["name"],
                    form_data["description"],
                ),
            )
            template_id = int(cursor.lastrowid)
            sync_day_template_entries(template_id, form_data["selected_map"])
            get_db().commit()
            flash("Die Tagesvorlage wurde gespeichert.", "success")
            return redirect(url_for("main.template_library"))
    return render_template(
        "library/day_form.html",
        template=None,
        form_data=form_data,
        dayparts=get_dayparts(),
        daypart_sections=build_template_day_sections(form_data["selected_map"]),
        visibility_options=VISIBILITY_FORM_OPTIONS,
        name_suggestions=DAY_TEMPLATE_NAME_SUGGESTIONS,
        source_date=source_date,
    )


@main_bp.route("/templates/day/<int:template_id>/edit", methods=("GET", "POST"))
@login_required
def day_template_edit(template_id: int):
    try:
        template = get_day_template(template_id)
        ensure_can_edit(template, "Diese Tagesvorlage kannst du gerade nicht bearbeiten.")
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(url_for("main.template_library"))

    form_data = day_template_form_data(template=template)
    if request.method == "POST":
        form_data = extract_day_template_form_data(form_data)
        if not form_data["name"]:
            flash("Bitte einen Namen für die Tagesvorlage eintragen.", "error")
        else:
            get_db().execute(
                """
                UPDATE day_templates
                SET name = ?, description = ?, visibility = ?, updated_at = CURRENT_TIMESTAMP
                WHERE id = ?
                """,
                (
                    form_data["name"],
                    form_data["description"],
                    form_data["visibility"],
                    template_id,
                ),
            )
            sync_day_template_entries(template_id, form_data["selected_map"])
            get_db().commit()
            flash("Die Tagesvorlage wurde aktualisiert.", "success")
            return redirect(url_for("main.template_library"))
    return render_template(
        "library/day_form.html",
        template=template,
        form_data=form_data,
        dayparts=get_dayparts(),
        daypart_sections=build_template_day_sections(form_data["selected_map"]),
        visibility_options=VISIBILITY_FORM_OPTIONS,
        name_suggestions=DAY_TEMPLATE_NAME_SUGGESTIONS,
        source_date=None,
    )


@main_bp.post("/templates/day/<int:template_id>/apply")
@login_required
def day_template_apply(template_id: int):
    selected_date = parse_plan_date(request.form.get("target_date"))
    inserted = apply_day_template(template_id, selected_date)
    flash(f"Die Tagesvorlage wurde angewendet und hat {inserted} Einträge ergänzt.", "success")
    return redirect(url_for("main.planner_day", date=selected_date.isoformat()))


@main_bp.route("/templates/week/new", methods=("GET", "POST"))
@login_required
def week_template_create():
    source_week_raw = request.values.get("source_week", "").strip()
    source_week = parse_week_start(source_week_raw) if source_week_raw else None
    form_data = week_template_form_data(source_week=source_week)
    if request.method == "POST":
        form_data = extract_week_template_form_data(form_data)
        if not form_data["name"]:
            flash("Bitte einen Namen für die Wochenvorlage eintragen.", "error")
        else:
            cursor = get_db().execute(
                """
                INSERT INTO week_templates (household_id, owner_user_id, visibility, name, description)
                VALUES (?, ?, ?, ?, ?)
                """,
                (
                    current_household_id(),
                    g.user["id"],
                    form_data["visibility"],
                    form_data["name"],
                    form_data["description"],
                ),
            )
            template_id = int(cursor.lastrowid)
            selected_map = dict(form_data["selected_map"])
            if form_data["source_week"]:
                source_start = parse_week_start(form_data["source_week"])
                for weekday_index in range(7):
                    if selected_map.get(weekday_index):
                        continue
                    if form_data["copy_from_source"].get(weekday_index):
                        snapshot_date = source_start + timedelta(days=weekday_index)
                        snapshot_name = f"{form_data['name']} · {WEEKDAY_LABELS[weekday_index]}"
                        snapshot_id = create_day_template_snapshot(
                            snapshot_name,
                            f"Automatisch aus der Woche {source_start.strftime('%d.%m.%Y')} übernommen.",
                            form_data["visibility"],
                            snapshot_date,
                        )
                        if snapshot_id:
                            selected_map[weekday_index] = snapshot_id
            sync_week_template_days(template_id, selected_map)
            get_db().commit()
            flash("Die Wochenvorlage wurde gespeichert.", "success")
            return redirect(url_for("main.template_library"))
    return render_template(
        "library/week_form.html",
        template=None,
        form_data=form_data,
        visibility_options=VISIBILITY_FORM_OPTIONS,
        name_suggestions=WEEK_TEMPLATE_NAME_SUGGESTIONS,
        day_templates=fetch_day_templates(),
        weekday_labels=WEEKDAY_LABELS,
        source_week=source_week,
    )


@main_bp.route("/templates/week/<int:template_id>/edit", methods=("GET", "POST"))
@login_required
def week_template_edit(template_id: int):
    try:
        template = get_week_template(template_id)
        ensure_can_edit(template, "Diese Wochenvorlage kannst du gerade nicht bearbeiten.")
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(url_for("main.template_library"))

    form_data = week_template_form_data(template=template)
    if request.method == "POST":
        form_data = extract_week_template_form_data(form_data)
        if not form_data["name"]:
            flash("Bitte einen Namen für die Wochenvorlage eintragen.", "error")
        else:
            get_db().execute(
                """
                UPDATE week_templates
                SET name = ?, description = ?, visibility = ?, updated_at = CURRENT_TIMESTAMP
                WHERE id = ?
                """,
                (
                    form_data["name"],
                    form_data["description"],
                    form_data["visibility"],
                    template_id,
                ),
            )
            sync_week_template_days(template_id, form_data["selected_map"])
            get_db().commit()
            flash("Die Wochenvorlage wurde aktualisiert.", "success")
            return redirect(url_for("main.template_library"))
    return render_template(
        "library/week_form.html",
        template=template,
        form_data=form_data,
        visibility_options=VISIBILITY_FORM_OPTIONS,
        name_suggestions=WEEK_TEMPLATE_NAME_SUGGESTIONS,
        day_templates=fetch_day_templates(),
        weekday_labels=WEEKDAY_LABELS,
        source_week=None,
    )


@main_bp.post("/templates/week/<int:template_id>/apply")
@login_required
def week_template_apply(template_id: int):
    week_start = parse_week_start(request.form.get("target_week"))
    inserted = apply_week_template(template_id, week_start)
    flash(f"Die Wochenvorlage wurde angewendet und hat {inserted} Einträge ergänzt.", "success")
    return redirect(url_for("main.planner", week=week_start.isoformat()))


@main_bp.route("/templates/set/new", methods=("GET", "POST"))
@login_required
def item_set_create():
    form_data = {
        "name": "",
        "description": "",
        "visibility": "shared",
        "item_ids": [],
        "item_search": "",
    }
    if request.method == "POST":
        form_data = extract_item_set_form_data(form_data)
        if not form_data["name"]:
            flash("Bitte einen Namen für das Paket eintragen.", "error")
        else:
            cursor = get_db().execute(
                """
                INSERT INTO item_sets (household_id, owner_user_id, visibility, name, description)
                VALUES (?, ?, ?, ?, ?)
                """,
                (
                    current_household_id(),
                    g.user["id"],
                    form_data["visibility"],
                    form_data["name"],
                    form_data["description"],
                ),
            )
            set_id = int(cursor.lastrowid)
            sync_item_set_items(set_id, form_data["item_ids"])
            get_db().commit()
            flash("Das Paket wurde gespeichert.", "success")
            return redirect(url_for("main.template_library"))
    items = fetch_items(include_archived=False, query=form_data["item_search"] or None)
    return render_template(
        "library/set_form.html",
        item_set=None,
        form_data=form_data,
        visibility_options=VISIBILITY_FORM_OPTIONS,
        name_suggestions=ITEM_SET_NAME_SUGGESTIONS,
        item_groups=group_items_by_availability(items),
    )


@main_bp.route("/templates/set/<int:set_id>/edit", methods=("GET", "POST"))
@login_required
def item_set_edit(set_id: int):
    try:
        item_set = get_item_set(set_id)
        ensure_can_edit(item_set, "Dieses Paket kannst du gerade nicht bearbeiten.")
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(url_for("main.template_library"))

    form_data = {
        "name": item_set["name"],
        "description": item_set["description"] or "",
        "visibility": item_set["visibility"],
        "item_ids": get_item_set_selected_ids(set_id),
        "item_search": "",
    }
    if request.method == "POST":
        form_data = extract_item_set_form_data(form_data)
        if not form_data["name"]:
            flash("Bitte einen Namen für das Paket eintragen.", "error")
        else:
            get_db().execute(
                """
                UPDATE item_sets
                SET name = ?, description = ?, visibility = ?, updated_at = CURRENT_TIMESTAMP
                WHERE id = ?
                """,
                (
                    form_data["name"],
                    form_data["description"],
                    form_data["visibility"],
                    set_id,
                ),
            )
            sync_item_set_items(set_id, form_data["item_ids"])
            get_db().commit()
            flash("Das Paket wurde aktualisiert.", "success")
            return redirect(url_for("main.template_library"))
    items = fetch_items(include_archived=False, query=form_data["item_search"] or None)
    return render_template(
        "library/set_form.html",
        item_set=item_set,
        form_data=form_data,
        visibility_options=VISIBILITY_FORM_OPTIONS,
        name_suggestions=ITEM_SET_NAME_SUGGESTIONS,
        item_groups=group_items_by_availability(items),
    )


@main_bp.post("/templates/set/<int:set_id>/apply")
@login_required
def item_set_apply(set_id: int):
    result = apply_item_set_to_shopping(set_id)
    if result["count"]:
        flash(f"Das Paket wurde auf die Einkaufsliste übernommen: {', '.join(result['names'][:4])}.", "success")
    else:
        flash("Das Paket ist bereits vollständig auf der Einkaufsliste oder zuhause vorhanden.", "info")
    return redirect(url_for("main.shopping_list"))


@main_bp.route("/settings", methods=("GET", "POST"))
@login_required
def settings_view():
    if request.method == "POST":
        form_name = request.form.get("form_name", "").strip()
        if form_name == "household":
            shopping_weekday = normalize_weekday(request.form.get("shopping_weekday"), 5)
            raw_prep_days = request.form.get("shopping_prep_days", "1").strip()
            shopping_prep_days = max(0, min(7, int(raw_prep_days))) if raw_prep_days.isdigit() else 1
            shopping_reminder_time = request.form.get("shopping_reminder_time", "18:00").strip() or "18:00"
            get_db().execute(
                """
                UPDATE households
                SET shopping_weekday = ?, shopping_prep_days = ?, shopping_reminder_time = ?
                WHERE id = ?
                """,
                (shopping_weekday, shopping_prep_days, shopping_reminder_time, current_household_id()),
            )
            get_db().commit()
            flash("Die Einkaufsrhythmus-Einstellungen wurden gespeichert.", "success")
        elif form_name == "reminders":
            ensure_user_settings_row()
            suggestion_style = normalize_suggestion_style(request.form.get("suggestion_style"), "balanced")
            get_db().execute(
                """
                UPDATE user_settings
                SET reminders_enabled = ?,
                    push_enabled = ?,
                    notification_channel = ?,
                    suggestion_style = ?,
                    energy_preference = ?,
                    remind_before_shopping = ?,
                    remind_on_shopping_day = ?,
                    show_missing_for_upcoming_week = ?,
                    show_planned_not_shopped = ?,
                    remind_tomorrow_if_sparse = ?,
                    remind_week_if_sparse = ?,
                    push_missing_breakfast = ?,
                    push_missing_lunch = ?,
                    push_missing_dinner = ?,
                    suggest_home_for_today = ?,
                    remind_small_snack = ?,
                    remind_nuts = ?,
                    show_meal_balancing = ?,
                    suggest_templates = ?,
                    suggest_patterns = ?,
                    updated_at = CURRENT_TIMESTAMP
                WHERE user_id = ?
                """,
                (
                    parse_checkbox("reminders_enabled", True),
                    parse_checkbox("push_enabled", False),
                    normalize_notification_channel(request.form.get("notification_channel"), "in_app"),
                    suggestion_style,
                    suggestion_style_energy_preference(suggestion_style),
                    parse_checkbox("remind_before_shopping", True),
                    parse_checkbox("remind_on_shopping_day", True),
                    parse_checkbox("show_missing_for_upcoming_week", True),
                    parse_checkbox("show_planned_not_shopped", True),
                    parse_checkbox("remind_tomorrow_if_sparse", True),
                    parse_checkbox("remind_week_if_sparse", True),
                    parse_checkbox("push_missing_breakfast", False),
                    parse_checkbox("push_missing_lunch", False),
                    parse_checkbox("push_missing_dinner", False),
                    parse_checkbox("suggest_home_for_today", True),
                    parse_checkbox("remind_small_snack", False),
                    parse_checkbox("remind_nuts", False),
                    parse_checkbox("show_meal_balancing", True),
                    parse_checkbox("suggest_templates", True),
                    parse_checkbox("suggest_patterns", True),
                    g.user["id"],
                ),
            )
            get_db().commit()
            flash("Deine Erinnerungen und Hinweise wurden gespeichert.", "success")
        elif form_name == "push_test":
            subscription = get_db().execute(
                """
                SELECT endpoint, p256dh, auth
                FROM push_subscriptions
                WHERE user_id = ? AND is_active = 1
                ORDER BY updated_at DESC
                LIMIT 1
                """,
                (g.user["id"],),
            ).fetchone()
            if subscription is None:
                flash("Bitte aktiviere zuerst Push im Browser oder auf dem Home-Bildschirm.", "error")
            else:
                ok, error = send_push_message(
                    {
                        "endpoint": subscription["endpoint"],
                        "keys": {"p256dh": subscription["p256dh"], "auth": subscription["auth"]},
                    },
                    title="Nouri",
                    body="Push ist bereit. Erinnerungen können später darüber kommen.",
                    url=url_for("main.settings_view", _external=True),
                )
                if ok:
                    get_db().execute(
                        "UPDATE push_subscriptions SET last_test_at = CURRENT_TIMESTAMP WHERE endpoint = ?",
                        (subscription["endpoint"],),
                    )
                    get_db().commit()
                    flash("Die Test-Mitteilung wurde versendet.", "success")
                else:
                    flash(error or "Die Test-Mitteilung konnte gerade nicht gesendet werden.", "error")
        return redirect(url_for("main.settings_view"))

    household_settings = get_household_settings()
    user_settings = get_user_settings()
    push_subscription = get_db().execute(
        """
        SELECT COUNT(*) AS count
        FROM push_subscriptions
        WHERE user_id = ? AND is_active = 1
        """,
        (g.user["id"],),
    ).fetchone()
    return render_template(
        "settings.html",
        household_settings=household_settings,
        user_settings=user_settings,
        push_subscription_count=int(push_subscription["count"]),
        push_ready=push_is_configured(),
        push_public_key_value=push_public_key(),
        restore_confirmation_text=RESTORE_CONFIRMATION_TEXT,
    )


@main_bp.get("/settings/backup/export")
@login_required
@admin_required
def backup_export():
    archive_path, download_name = export_backup_archive(
        get_db(),
        current_app.config["UPLOAD_FOLDER"],
        current_app.config["APP_VERSION"],
    )

    @after_this_request
    def cleanup_backup(response):
        Path(archive_path).unlink(missing_ok=True)
        return response

    return send_file(
        archive_path,
        as_attachment=True,
        download_name=download_name,
        mimetype="application/zip",
        max_age=0,
    )


@main_bp.post("/settings/backup/restore")
@login_required
@admin_required
def backup_restore():
    confirmation = request.form.get("restore_confirmation", "").strip().upper()
    backup_file = request.files.get("backup_file")
    if confirmation != RESTORE_CONFIRMATION_TEXT:
        flash("Bitte die Bestätigung genau eintragen, bevor das Backup wiederhergestellt wird.", "error")
        return redirect(url_for("main.settings_view"))
    if not backup_file or not backup_file.filename:
        flash("Bitte zuerst eine Backup-Datei auswählen.", "error")
        return redirect(url_for("main.settings_view"))

    try:
        metadata = restore_backup_archive(get_db(), current_app.config["UPLOAD_FOLDER"], backup_file)
        get_db().commit()
    except Exception as exc:
        get_db().rollback()
        flash(str(exc) or "Das Backup konnte gerade nicht wiederhergestellt werden.", "error")
        return redirect(url_for("main.settings_view"))

    version_label = metadata.get("app_version") or "einer älteren Version"
    flash(f"Das Backup aus {version_label} wurde wiederhergestellt.", "success")
    return redirect(url_for("main.settings_view"))


@main_bp.post("/push/subscribe")
@login_required
def push_subscribe():
    if not push_is_configured():
        return jsonify({"ok": False, "error": "Push ist noch nicht konfiguriert."}), 400
    endpoint = request.form.get("endpoint", "").strip()
    p256dh = request.form.get("p256dh", "").strip()
    auth_key = request.form.get("auth", "").strip()
    if not endpoint or not p256dh or not auth_key:
        return jsonify({"ok": False, "error": "Unvollständige Push-Daten."}), 400

    get_db().execute(
        """
        INSERT INTO push_subscriptions (user_id, endpoint, p256dh, auth, user_agent, is_active)
        VALUES (?, ?, ?, ?, ?, 1)
        ON CONFLICT(endpoint) DO UPDATE SET
            user_id = excluded.user_id,
            p256dh = excluded.p256dh,
            auth = excluded.auth,
            user_agent = excluded.user_agent,
            is_active = 1,
            updated_at = CURRENT_TIMESTAMP
        """,
        (g.user["id"], endpoint, p256dh, auth_key, request.headers.get("User-Agent", "")),
    )
    ensure_user_settings_row()
    get_db().execute(
        "UPDATE user_settings SET push_enabled = 1, updated_at = CURRENT_TIMESTAMP WHERE user_id = ?",
        (g.user["id"],),
    )
    get_db().commit()
    return jsonify({"ok": True})


@main_bp.post("/push/unsubscribe")
@login_required
def push_unsubscribe():
    endpoint = request.form.get("endpoint", "").strip()
    if endpoint:
        get_db().execute(
            "UPDATE push_subscriptions SET is_active = 0, updated_at = CURRENT_TIMESTAMP WHERE endpoint = ? AND user_id = ?",
            (endpoint, g.user["id"]),
        )
    else:
        get_db().execute(
            "UPDATE push_subscriptions SET is_active = 0, updated_at = CURRENT_TIMESTAMP WHERE user_id = ?",
            (g.user["id"],),
        )
    get_db().commit()
    return jsonify({"ok": True})


@main_bp.route("/items/<kind>")
@login_required
def item_list(kind: str):
    if kind not in ITEM_KIND_LABELS:
        return redirect(url_for("main.dashboard"))

    query = request.args.get("q", "").strip()
    state = request.args.get("state", "").strip()
    scope = request.args.get("visibility", "").strip()
    raw_daypart_id = request.args.get("daypart_id", "").strip()
    daypart_id = int(raw_daypart_id) if raw_daypart_id.isdigit() else None

    items = fetch_items(
        kind=kind,
        availability=state or None,
        query=query or None,
        daypart_id=daypart_id,
        visibility=scope or None,
    )
    return render_template(
        "items/list.html",
        kind=kind,
        items=items,
        availability_labels=AVAILABILITY_LABELS,
        query=query,
        selected_state=state,
        selected_visibility=scope,
        selected_daypart_id=daypart_id,
        dayparts=get_dayparts(),
        state_options=ACTIVE_STATE_OPTIONS,
        visibility_options=VISIBILITY_FILTER_OPTIONS,
        today=date.today(),
    )


@main_bp.route("/items/<kind>/new", methods=("GET", "POST"))
@login_required
def item_create(kind: str):
    if kind not in ITEM_KIND_LABELS:
        return redirect(url_for("main.dashboard"))

    form_data = {
        "name": request.args.get("name", "").strip(),
        "category": "",
        "energy_density": "neutral",
        "note": "",
        "visibility": "shared",
        "target_user_id": None,
        "target_user_raw": TARGET_USER_OPTIONS_DEFAULT,
        "food_search": "",
        "daypart_ids": [],
        "component_ids": [int(value) for value in request.args.getlist("component_ids") if value.isdigit()],
        "quick_food_name": "",
        "quick_food_category": "",
        "quick_food_energy_density": "neutral",
        "quick_food_note": "",
    }

    if request.method == "POST":
        form_action = request.form.get("form_action", "save_item")
        form_data = extract_item_form_data(form_data)

        if kind == "meal" and form_action == "filter_foods":
            return render_item_form(kind, item=None, form_data=form_data)

        if kind == "meal" and form_action == "quick_add_food":
            if not form_data["quick_food_name"]:
                flash("Bitte einen Namen für das neue Lebensmittel eintragen.", "error")
            else:
                new_food_id = create_quick_food_from_form(form_data)
                if new_food_id not in form_data["component_ids"]:
                    form_data["component_ids"].append(new_food_id)
                form_data["quick_food_name"] = ""
                form_data["quick_food_category"] = ""
                form_data["quick_food_note"] = ""
                flash("Das neue Lebensmittel wurde angelegt und direkt zur Mahlzeitenidee hinzugefügt.", "success")
                return render_item_form(kind, item=None, form_data=form_data)

        error = None
        if not form_data["name"]:
            error = "Bitte einen Namen eintragen."

        photo_filename = None
        if error is None:
            try:
                photo_filename = save_photo(request.files.get("photo"))
            except ValueError as exc:
                error = str(exc)

        if error is None:
            cursor = get_db().execute(
                """
                INSERT INTO items (
                    household_id, owner_user_id, target_user_id, visibility, kind, name, category, energy_density, note, photo_filename, created_by, updated_by
                )
                VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
                """,
                (
                    current_household_id(),
                    g.user["id"],
                    form_data["target_user_id"],
                    form_data["visibility"],
                    kind,
                    form_data["name"],
                    form_data["category"],
                    form_data["energy_density"],
                    form_data["note"],
                    photo_filename,
                    g.user["id"],
                    g.user["id"],
                ),
            )
            item_id = int(cursor.lastrowid)
            sync_item_dayparts(item_id, form_data["daypart_ids"])
            if kind == "meal":
                sync_meal_components(item_id, form_data["component_ids"])
            get_db().commit()
            flash(f"{ITEM_KIND_SINGULAR_LABELS[kind]} wurde angelegt.", "success")
            return redirect(url_for("main.item_list", kind=kind))
        flash(error, "error")

    return render_item_form(kind, item=None, form_data=form_data)


@main_bp.route("/items/<int:item_id>/edit", methods=("GET", "POST"))
@login_required
def item_edit(item_id: int):
    try:
        item = get_item(item_id)
        ensure_can_edit(item)
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(url_for("main.dashboard"))

    form_data = {
        "name": item["name"],
        "category": item["category"] or "",
        "energy_density": item.get("energy_density") or "neutral",
        "note": item["note"] or "",
        "visibility": item["visibility"],
        "target_user_id": item["target_user_id"],
        "target_user_raw": str(item["target_user_id"]) if item["target_user_id"] else TARGET_USER_OPTIONS_DEFAULT,
        "food_search": "",
        "daypart_ids": get_item_daypart_ids(item_id),
        "component_ids": get_meal_component_ids(item_id) if item["kind"] == "meal" else [],
        "quick_food_name": "",
        "quick_food_category": "",
        "quick_food_energy_density": "neutral",
        "quick_food_note": "",
    }

    if request.method == "POST":
        form_action = request.form.get("form_action", "save_item")
        form_data = extract_item_form_data(form_data)

        if item["kind"] == "meal" and form_action == "filter_foods":
            return render_item_form(item["kind"], item=item, form_data=form_data)

        if item["kind"] == "meal" and form_action == "quick_add_food":
            if not form_data["quick_food_name"]:
                flash("Bitte einen Namen für das neue Lebensmittel eintragen.", "error")
            else:
                new_food_id = create_quick_food_from_form(form_data)
                if new_food_id not in form_data["component_ids"]:
                    form_data["component_ids"].append(new_food_id)
                form_data["quick_food_name"] = ""
                form_data["quick_food_category"] = ""
                form_data["quick_food_note"] = ""
                flash("Das neue Lebensmittel wurde angelegt und direkt zur Mahlzeitenidee hinzugefügt.", "success")
                return render_item_form(item["kind"], item=item, form_data=form_data)

        error = None
        if not form_data["name"]:
            error = "Bitte einen Namen eintragen."

        photo_filename = item["photo_filename"]
        if error is None:
            try:
                photo_filename = save_photo(request.files.get("photo"), current_filename=item["photo_filename"])
            except ValueError as exc:
                error = str(exc)

        if error is None:
            get_db().execute(
                """
                UPDATE items
                SET name = ?,
                    category = ?,
                    energy_density = ?,
                    note = ?,
                    visibility = ?,
                    target_user_id = ?,
                    photo_filename = ?,
                    updated_by = ?,
                    updated_at = CURRENT_TIMESTAMP
                WHERE id = ?
                """,
                (
                    form_data["name"],
                    form_data["category"],
                    form_data["energy_density"],
                    form_data["note"],
                    form_data["visibility"],
                    form_data["target_user_id"],
                    photo_filename,
                    g.user["id"],
                    item_id,
                ),
            )
            sync_item_dayparts(item_id, form_data["daypart_ids"])
            if item["kind"] == "meal":
                sync_meal_components(item_id, form_data["component_ids"])
            get_db().commit()
            flash("Der Eintrag wurde aktualisiert.", "success")
            return redirect(url_for("main.item_list", kind=item["kind"]))
        flash(error, "error")

    return render_item_form(item["kind"], item=item, form_data=form_data)


@main_bp.post("/items/<int:item_id>/shopping")
@login_required
def item_add_to_shopping(item_id: int):
    try:
        item = get_item(item_id)
    except ValueError as exc:
        flash(str(exc), "error")
        return redirect(request.referrer or url_for("main.shopping_list"))

    result = ensure_item_or_missing_components_are_shopped(
        item_id,
        g.user["id"],
        item["visibility"],
    )
    if result["count"]:
        if result["used_components"]:
            flash(f"Für „{item['name']}“ wurden fehlende Lebensmittel auf die Einkaufsliste gesetzt.", "success")
        else:
            flash(f"{item['name']} steht jetzt auf der Einkaufsliste.", "success")
    elif result["scheduled_count"]:
        flash(f"Für „{item['name']}“ sind fehlende Lebensmittel für einen späteren Einkauf vorgemerkt.", "info")
    else:
        flash(f"Für „{item['name']}“ ist gerade nichts zusätzlich nötig.", "info")
    return redirect(request.referrer or url_for("main.shopping_list"))


@main_bp.post("/items/<int:item_id>/set-home")
@login_required
def item_set_home(item_id: int):
    try:
        item = get_item(item_id)
        ensure_can_edit(item)
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(request.referrer or url_for("main.home_view"))

    get_db().execute(
        "UPDATE items SET availability_state = 'home', updated_by = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?",
        (g.user["id"], item_id),
    )
    get_db().commit()
    flash(f"{item['name']} ist jetzt unter Zuhause sichtbar.", "success")
    return redirect(request.referrer or url_for("main.home_view"))


@main_bp.post("/items/<int:item_id>/archive")
@login_required
def item_archive(item_id: int):
    try:
        item = get_item(item_id)
        ensure_can_edit(item)
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(request.referrer or url_for("main.archive_view"))

    get_db().execute(
        "UPDATE items SET availability_state = 'archived', updated_by = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?",
        (g.user["id"], item_id),
    )
    get_db().commit()
    flash(f"{item['name']} liegt jetzt im Archiv und bleibt später leicht wiederfindbar.", "info")
    return redirect(request.referrer or url_for("main.archive_view"))


@main_bp.post("/items/<int:item_id>/restore")
@login_required
def item_restore(item_id: int):
    try:
        item = get_item(item_id)
        ensure_can_edit(item)
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(request.referrer or url_for("main.archive_view"))

    get_db().execute(
        "UPDATE items SET availability_state = 'idea', updated_by = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?",
        (g.user["id"], item_id),
    )
    get_db().commit()
    flash(f"{item['name']} ist wieder in der aktiven Liste.", "success")
    return redirect(request.referrer or url_for("main.archive_view"))


@main_bp.route("/shopping", methods=("GET", "POST"))
@login_required
def shopping_list():
    if request.method == "POST":
        selected_item_id = request.form.get("item_id", "").strip()
        if not selected_item_id.isdigit():
            flash("Bitte zuerst etwas auswählen.", "error")
        else:
            try:
                item = get_item(int(selected_item_id))
                result = ensure_item_or_missing_components_are_shopped(
                    item["id"],
                    g.user["id"],
                    item["visibility"],
                )
                if result["count"]:
                    flash(f"Die Einkaufsliste wurde ergänzt: {', '.join(result['names'][:4])}.", "success")
                elif result["scheduled_count"]:
                    flash("Ein paar Dinge sind für einen späteren Einkauf vorgemerkt.", "info")
                else:
                    flash("Dafür ist gerade nichts zusätzlich nötig.", "info")
            except ValueError as exc:
                flash(str(exc), "error")
        return redirect(url_for("main.shopping_list"))

    entries = fetch_shopping_entries()
    upcoming_entries = fetch_upcoming_shopping_needs()
    addable_items = fetch_items(include_archived=False)
    addable_items = [item for item in addable_items if not item["is_on_shopping_list"]]
    household_settings = get_household_settings()
    shopping_weekday_label = dict(WEEKDAY_OPTIONS).get(household_settings["shopping_weekday"], "gesetzt")
    return render_template(
        "shopping/list.html",
        entries=entries,
        upcoming_entries=upcoming_entries,
        addable_items=addable_items,
        household_settings=household_settings,
        shopping_weekday_label=shopping_weekday_label,
    )


@main_bp.post("/shopping/<int:entry_id>/check")
@login_required
def shopping_check(entry_id: int):
    entry = get_db().execute(
        f"""
        SELECT shopping_entries.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username
        FROM shopping_entries
        LEFT JOIN users AS owner ON owner.id = shopping_entries.owner_user_id
        WHERE shopping_entries.id = ? AND {visible_clause('shopping_entries')}
        """,
        [entry_id, *visible_params()],
    ).fetchone()
    if entry is None:
        flash("Der Einkaufseintrag wurde nicht gefunden.", "error")
        return redirect(url_for("main.shopping_list"))

    entry_dict = describe_record(dict(entry))
    try:
        ensure_can_edit(entry_dict, "Diesen Einkaufseintrag kannst du gerade nicht ändern.")
        item = get_item(entry["item_id"])
    except (ValueError, PermissionError) as exc:
        flash(str(exc), "error")
        return redirect(url_for("main.shopping_list"))

    get_db().execute(
        "UPDATE shopping_entries SET is_checked = 1, checked_at = CURRENT_TIMESTAMP, checked_by = ? WHERE id = ?",
        (g.user["id"], entry_id),
    )
    get_db().execute(
        "UPDATE items SET availability_state = 'home', updated_by = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?",
        (g.user["id"], item["id"]),
    )
    get_db().commit()
    flash(f"{item['name']} ist jetzt als Zuhause vorhanden markiert.", "success")
    return redirect(url_for("main.shopping_list"))


@main_bp.post("/shopping/<int:entry_id>/remove")
@login_required
def shopping_remove(entry_id: int):
    entry = get_db().execute(
        f"""
        SELECT shopping_entries.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username
        FROM shopping_entries
        LEFT JOIN users AS owner ON owner.id = shopping_entries.owner_user_id
        WHERE shopping_entries.id = ? AND {visible_clause('shopping_entries')}
        """,
        [entry_id, *visible_params()],
    ).fetchone()
    if entry is None:
        flash("Der Eintrag wurde nicht gefunden.", "error")
        return redirect(url_for("main.shopping_list"))
    try:
        ensure_can_edit(describe_record(dict(entry)), "Diesen Einkaufseintrag kannst du gerade nicht entfernen.")
    except PermissionError as exc:
        flash(str(exc), "error")
        return redirect(url_for("main.shopping_list"))
    get_db().execute("DELETE FROM shopping_entries WHERE id = ?", (entry_id,))
    get_db().commit()
    flash("Der Eintrag wurde von der Einkaufsliste entfernt.", "info")
    return redirect(url_for("main.shopping_list"))


@main_bp.get("/home")
@login_required
def home_view():
    query = request.args.get("q", "").strip()
    scope = request.args.get("visibility", "").strip()
    raw_daypart_id = request.args.get("daypart_id", "").strip()
    daypart_id = int(raw_daypart_id) if raw_daypart_id.isdigit() else None
    dayparts = get_dayparts()
    items = fetch_items(
        availability="home",
        query=query or None,
        daypart_id=daypart_id,
        visibility=scope or None,
    )
    return render_template(
        "home/list.html",
        sections=build_home_sections(items, dayparts, daypart_id),
        recipe_suggestions=build_home_recipe_suggestions(daypart_id, limit=4),
        query=query,
        dayparts=dayparts,
        selected_daypart_id=daypart_id,
        selected_visibility=scope,
        visibility_options=VISIBILITY_FILTER_OPTIONS,
        today=date.today(),
    )


@main_bp.get("/archive")
@login_required
def archive_view():
    query = request.args.get("q", "").strip()
    selected_kind = request.args.get("kind", "").strip()
    selected_visibility = request.args.get("visibility", "").strip()
    kind = selected_kind if selected_kind in ITEM_KIND_LABELS else None
    items = fetch_items(
        kind=kind,
        availability="archived",
        include_archived=True,
        query=query or None,
        visibility=selected_visibility or None,
    )
    return render_template(
        "archive/list.html",
        items=items,
        query=query,
        selected_kind=selected_kind,
        selected_visibility=selected_visibility,
        kind_options=KIND_FILTER_OPTIONS,
        visibility_options=VISIBILITY_FILTER_OPTIONS,
        today=date.today(),
    )


@main_bp.get("/planner")
@login_required
def planner():
    week_start = parse_week_start(request.args.get("week"))
    return render_template(
        "planner/week.html",
        week_start=week_start,
        week_end=week_start + timedelta(days=6),
        prev_week=week_start - timedelta(days=7),
        next_week=week_start + timedelta(days=7),
        week_cards=fetch_week_cards(week_start),
        today=date.today(),
        week_templates=fetch_week_templates()[:6],
        week_hints=build_week_hints(week_start),
        upcoming_entries=fetch_upcoming_shopping_needs(limit=8),
        household_settings=get_household_settings(),
    )


@main_bp.route("/planner/day", methods=("GET", "POST"))
@login_required
def planner_day():
    selected_date = parse_plan_date(request.values.get("date"))

    if request.method == "POST":
        item_id_raw = request.form.get("item_id", "").strip()
        daypart_id_raw = request.form.get("daypart_id", "").strip()
        note = request.form.get("note", "").strip()
        selected_date = parse_plan_date(request.form.get("plan_date"))
        visibility = normalize_visibility(request.form.get("visibility"), "shared")
        if not item_id_raw.isdigit():
            flash("Bitte etwas für den Tagesplan auswählen.", "error")
        elif not daypart_id_raw.isdigit():
            flash("Bitte eine Tageszeit auswählen.", "error")
        else:
            item_id = int(item_id_raw)
            daypart_id = int(daypart_id_raw)
            try:
                get_item(item_id)
                shopping_result = insert_plan_entry(
                    item_id=item_id,
                    daypart_id=daypart_id,
                    plan_date=selected_date,
                    visibility=visibility,
                    note=note,
                )
                if shopping_result["count"]:
                    flash("Fehlende Lebensmittel wurden für den nächsten Einkauf ergänzt.", "info")
                elif shopping_result["scheduled_count"]:
                    flash("Fehlende Lebensmittel wurden für einen späteren Einkauf vorgemerkt.", "info")
                flash("Der Eintrag wurde in den Tagesplan gelegt.", "success")
                return redirect(
                    f"{url_for('main.planner_day', date=selected_date.isoformat(), daypart_id=daypart_id)}#daypart-{daypart_id}"
                )
            except ValueError as exc:
                flash(str(exc), "error")

    selected_item_raw = request.args.get("item_id", "").strip()
    selected_daypart_raw = request.args.get("daypart_id", "").strip()
    selected_meal_name = request.args.get("meal_name", "").strip()
    selected_components_raw = request.args.get("component_ids", "").strip()
    selected_item_id = int(selected_item_raw) if selected_item_raw.isdigit() else None
    selected_daypart_id = int(selected_daypart_raw) if selected_daypart_raw.isdigit() else None
    selected_component_ids = [int(value) for value in selected_components_raw.split(",") if value.isdigit()]
    return render_template(
        "planner/day.html",
        selected_date=selected_date,
        previous_day=selected_date - timedelta(days=1),
        next_day=selected_date + timedelta(days=1),
        sections=build_day_planner_sections(
            selected_date,
            selected_item_id,
            selected_daypart_id,
            selected_meal_name=selected_meal_name,
            selected_component_ids=selected_component_ids,
        ),
        today=date.today(),
        visibility_options=VISIBILITY_FORM_OPTIONS,
        day_templates=fetch_day_templates()[:6],
        day_hints=build_day_hints(selected_date),
    )


@main_bp.post("/planner/day/generated-meal")
@login_required
def planner_generated_meal():
    selected_date = parse_plan_date(request.form.get("plan_date"))
    daypart_raw = request.form.get("daypart_id", "").strip()
    meal_name = request.form.get("meal_name", "").strip()
    component_ids = [int(value) for value in request.form.getlist("component_ids") if value.isdigit()]
    visibility = normalize_visibility(request.form.get("visibility"), "shared")
    if not daypart_raw.isdigit() or not meal_name or not component_ids:
        flash("Die vorgeschlagene Kombination konnte gerade nicht übernommen werden.", "error")
        return redirect(url_for("main.planner_day", date=selected_date.isoformat()))

    daypart_id = int(daypart_raw)
    meal_id = create_or_get_generated_meal(
        name=meal_name,
        component_ids=component_ids,
        daypart_id=daypart_id,
        visibility=visibility,
    )
    shopping_result = insert_plan_entry(
        item_id=meal_id,
        daypart_id=daypart_id,
        plan_date=selected_date,
        visibility=visibility,
    )
    if shopping_result["count"]:
        flash("Die Kombination wurde eingeplant und fehlende Lebensmittel wurden ergänzt.", "info")
    elif shopping_result["scheduled_count"]:
        flash("Die Kombination wurde eingeplant. Fehlende Lebensmittel sind für später vorgemerkt.", "info")
    flash("Die Kombination wurde als Mahlzeitenidee übernommen.", "success")
    return redirect(f"{url_for('main.planner_day', date=selected_date.isoformat(), daypart_id=daypart_id)}#daypart-{daypart_id}")


@main_bp.post("/planner/<int:entry_id>/remove")
@login_required
def planner_remove(entry_id: int):
    selected_date = request.args.get("date", "")
    entry = get_db().execute(
        f"""
        SELECT plan_entries.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username
        FROM plan_entries
        LEFT JOIN users AS owner ON owner.id = plan_entries.owner_user_id
        WHERE plan_entries.id = ? AND {visible_clause('plan_entries')}
        """,
        [entry_id, *visible_params()],
    ).fetchone()
    if entry is None:
        flash("Der Planeintrag wurde nicht gefunden.", "error")
    else:
        try:
            ensure_can_edit(describe_record(dict(entry)), "Diesen Planeintrag kannst du gerade nicht entfernen.")
            get_db().execute("DELETE FROM plan_entries WHERE id = ?", (entry_id,))
            get_db().commit()
            flash("Der Planeintrag wurde entfernt.", "info")
        except PermissionError as exc:
            flash(str(exc), "error")
    if selected_date:
        return redirect(url_for("main.planner_day", date=selected_date))
    return redirect(url_for("main.planner"))


@main_bp.post("/planner/<int:entry_id>/move")
@login_required
def planner_move(entry_id: int):
    target_date = parse_plan_date(request.form.get("target_date"))
    target_daypart_raw = request.form.get("target_daypart_id", "").strip()
    if not target_daypart_raw.isdigit():
        return jsonify({"ok": False, "error": "Ungültige Tageszeit"}), 400

    entry = get_db().execute(
        f"""
        SELECT plan_entries.*,
               owner.display_name AS owner_display_name,
               owner.username AS owner_username
        FROM plan_entries
        LEFT JOIN users AS owner ON owner.id = plan_entries.owner_user_id
        WHERE plan_entries.id = ? AND {visible_clause('plan_entries')}
        """,
        [entry_id, *visible_params()],
    ).fetchone()
    if entry is None:
        return jsonify({"ok": False, "error": "Eintrag nicht gefunden"}), 404
    try:
        ensure_can_edit(describe_record(dict(entry)), "Diesen Planeintrag kannst du gerade nicht verschieben.")
    except PermissionError as exc:
        return jsonify({"ok": False, "error": str(exc)}), 403

    target_daypart_id = int(target_daypart_raw)
    get_db().execute(
        "UPDATE plan_entries SET plan_date = ?, daypart_id = ? WHERE id = ?",
        (target_date.isoformat(), target_daypart_id, entry_id),
    )
    get_db().commit()

    shopping_result = ensure_item_or_missing_components_are_shopped(
        entry["item_id"],
        g.user["id"],
        entry["visibility"],
        needed_for_date=target_date.isoformat(),
        needed_for_daypart_id=target_daypart_id,
        source_item_id=entry["item_id"],
    )
    if shopping_result["count"]:
        flash("Fehlende Lebensmittel wurden nach dem Verschieben ergänzt.", "info")
    elif shopping_result["scheduled_count"]:
        flash("Fehlende Lebensmittel sind für den passenden Einkauf vorgemerkt.", "info")
    return jsonify(
        {
            "ok": True,
            "added_to_shopping": bool(shopping_result["count"]),
            "redirect_url": url_for("main.planner", week=parse_week_start(target_date.isoformat()).isoformat()),
        }
    )