import { Database } from 'bun:sqlite';
import { join } from 'node:path';
import { mkdirSync } from 'node:fs';
import { SCHEMA, DEFAULT_CONFIG } from './schema';

const dataDir = process.env.DATA_DIR ?? './data';
mkdirSync(dataDir, { recursive: true });

const isDev = process.env.NODE_ENV === 'development';
const dbPath = join(dataDir, isDev ? 'netfelix-dev.db' : 'netfelix.db');

// ─── Env-var → config key mapping ─────────────────────────────────────────────

const ENV_MAP: Record<string, string> = {
	jellyfin_url: 'JELLYFIN_URL',
	jellyfin_api_key: 'JELLYFIN_API_KEY',
	jellyfin_user_id: 'JELLYFIN_USER_ID',
	radarr_url: 'RADARR_URL',
	radarr_api_key: 'RADARR_API_KEY',
	radarr_enabled: 'RADARR_ENABLED',
	sonarr_url: 'SONARR_URL',
	sonarr_api_key: 'SONARR_API_KEY',
	sonarr_enabled: 'SONARR_ENABLED',
	subtitle_languages: 'SUBTITLE_LANGUAGES',
};

/** Read a config key from environment variables (returns null if not set). */
function envValue(key: string): string | null {
	const envKey = ENV_MAP[key];
	if (!envKey) return null;
	const val = process.env[envKey];
	if (!val) return null;
	if (key.endsWith('_enabled')) return val === '1' || val.toLowerCase() === 'true' ? '1' : '0';
	if (key === 'subtitle_languages') return JSON.stringify(val.split(',').map((s) => s.trim()));
	if (key.endsWith('_url')) return val.replace(/\/$/, '');
	return val;
}

/** True when minimum required Jellyfin env vars are present — skips the setup wizard. */
function isEnvConfigured(): boolean {
	return !!(process.env.JELLYFIN_URL && process.env.JELLYFIN_API_KEY);
}

// ─── Database ──────────────────────────────────────────────────────────────────

let _db: Database | null = null;

export function getDb(): Database {
	if (_db) return _db;
	_db = new Database(dbPath, { create: true });
	_db.exec(SCHEMA);
	// Migrations for columns added after initial release
	try { _db.exec('ALTER TABLE stream_decisions ADD COLUMN custom_title TEXT'); } catch { /* already exists */ }
	try { _db.exec('ALTER TABLE review_plans ADD COLUMN subs_extracted INTEGER NOT NULL DEFAULT 0'); } catch { /* already exists */ }
	try { _db.exec("ALTER TABLE nodes ADD COLUMN movies_path TEXT NOT NULL DEFAULT ''"); } catch { /* already exists */ }
	try { _db.exec("ALTER TABLE nodes ADD COLUMN series_path TEXT NOT NULL DEFAULT ''"); } catch { /* already exists */ }
	seedDefaults(_db);
	return _db;
}

function seedDefaults(db: Database): void {
	const insert = db.prepare(
		'INSERT OR IGNORE INTO config (key, value) VALUES (?, ?)'
	);
	for (const [key, value] of Object.entries(DEFAULT_CONFIG)) {
		insert.run(key, value);
	}
}

export function getConfig(key: string): string | null {
	// Env vars take precedence over DB
	const fromEnv = envValue(key);
	if (fromEnv !== null) return fromEnv;
	// Auto-complete setup when all required Jellyfin env vars are present
	if (key === 'setup_complete' && isEnvConfigured()) return '1';
	const row = getDb()
		.prepare('SELECT value FROM config WHERE key = ?')
		.get(key) as { value: string } | undefined;
	return row?.value ?? null;
}

export function setConfig(key: string, value: string): void {
	getDb()
		.prepare('INSERT OR REPLACE INTO config (key, value) VALUES (?, ?)')
		.run(key, value);
}

/** Returns the set of config keys currently overridden by environment variables. */
export function getEnvLockedKeys(): Set<string> {
	const locked = new Set<string>();
	for (const key of Object.keys(ENV_MAP)) {
		if (envValue(key) !== null) locked.add(key);
	}
	return locked;
}

export function getAllConfig(): Record<string, string> {
	const rows = getDb()
		.prepare('SELECT key, value FROM config')
		.all() as { key: string; value: string }[];
	const result = Object.fromEntries(rows.map((r) => [r.key, r.value ?? '']));
	// Apply env overrides on top of DB values
	for (const key of Object.keys(ENV_MAP)) {
		const fromEnv = envValue(key);
		if (fromEnv !== null) result[key] = fromEnv;
	}
	// Auto-complete setup when all required Jellyfin env vars are present
	if (isEnvConfigured()) result.setup_complete = '1';
	return result;
}