<?php

declare(strict_types=1);

final class UserRepository
{
    private string $path;

    public function __construct()
    {
        $this->path = storage_path('system/users.json');
    }

    public function hasAnyUsers(): bool
    {
        return count($this->all()) > 0;
    }

    public function all(): array
    {
        $data = decode_json_file($this->path, ['users' => []]);

        return array_values(array_filter($data['users'] ?? [], 'is_array'));
    }

    public function find(string $username): ?array
    {
        $needle = normalize_username($username);

        foreach ($this->all() as $user) {
            if (($user['username'] ?? '') === $needle) {
                return $user;
            }
        }

        return null;
    }

    public function verify(string $username, string $password): ?array
    {
        $user = $this->find($username);

        if ($user === null) {
            return null;
        }

        if (!password_verify($password, (string) ($user['password_hash'] ?? ''))) {
            return null;
        }

        return $user;
    }

    public function create(string $username, string $password, bool $isAdmin = false): array
    {
        $normalized = normalize_username($username);

        if ($normalized === '' || $this->find($normalized) !== null) {
            throw new RuntimeException('Benutzername existiert bereits oder ist ungueltig.');
        }

        $users = $this->all();
        $users[] = [
            'username' => $normalized,
            'password_hash' => password_hash($password, PASSWORD_DEFAULT),
            'is_admin' => $isAdmin,
            'created_at' => date(DATE_ATOM),
        ];

        $this->write(['users' => $users]);

        return $this->find($normalized) ?? [];
    }

    public function changePassword(string $username, string $password): void
    {
        $normalized = normalize_username($username);
        $users = $this->all();

        foreach ($users as &$user) {
            if (($user['username'] ?? '') === $normalized) {
                $user['password_hash'] = password_hash($password, PASSWORD_DEFAULT);
                $user['updated_at'] = date(DATE_ATOM);
            }
        }
        unset($user);

        $this->write(['users' => $users]);
    }

    private function write(array $payload): void
    {
        if (!is_dir(dirname($this->path))) {
            mkdir(dirname($this->path), 0775, true);
        }

        file_put_contents(
            $this->path,
            json_encode($payload, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES)
        );
    }
}