CREATE TABLE show_live_states (
	show_id TEXT PRIMARY KEY REFERENCES shows(id) ON DELETE CASCADE,
	revision INTEGER NOT NULL DEFAULT 0 CHECK (revision >= 0),
	current_usage_id TEXT REFERENCES piece_usages(id) ON DELETE SET NULL,
	started_at_utc TEXT,
	ended_at_utc TEXT,
	presentation_usage_id TEXT REFERENCES piece_usages(id) ON DELETE SET NULL,
	presentation_revision INTEGER NOT NULL DEFAULT 0 CHECK (presentation_revision >= 0),
	updated_at_utc TEXT NOT NULL
);

CREATE TABLE live_usage_runs (
	id TEXT PRIMARY KEY,
	show_id TEXT NOT NULL REFERENCES shows(id) ON DELETE CASCADE,
	usage_id TEXT NOT NULL REFERENCES piece_usages(id) ON DELETE CASCADE,
	started_at_utc TEXT NOT NULL,
	ended_at_utc TEXT,
	CHECK (ended_at_utc IS NULL OR ended_at_utc >= started_at_utc)
);

CREATE UNIQUE INDEX idx_one_active_live_run_per_show
	ON live_usage_runs(show_id) WHERE ended_at_utc IS NULL;
CREATE INDEX idx_live_runs_usage ON live_usage_runs(usage_id, started_at_utc);

CREATE TABLE live_commands (
	show_id TEXT NOT NULL REFERENCES shows(id) ON DELETE CASCADE,
	command_id TEXT NOT NULL,
	action TEXT NOT NULL,
	result_revision INTEGER NOT NULL CHECK (result_revision >= 0),
	created_at_utc TEXT NOT NULL,
	PRIMARY KEY (show_id, command_id)
);

CREATE TABLE presentation_access_tokens (
	id TEXT PRIMARY KEY,
	show_id TEXT NOT NULL REFERENCES shows(id) ON DELETE CASCADE,
	token_hash TEXT NOT NULL UNIQUE,
	created_at_utc TEXT NOT NULL,
	revoked_at_utc TEXT
);

CREATE INDEX idx_presentation_tokens_show
	ON presentation_access_tokens(show_id, revoked_at_utc);

UPDATE piece_usages SET status = 'open' WHERE status = 'current';