import Database from 'better-sqlite3';
import path from 'path';

const DB_PATH = process.env.DATABASE_PATH || path.join(__dirname, '../../data/tracker.db');

let db: Database.Database;

export function getDb(): Database.Database {
  if (!db) {
    db = new Database(DB_PATH);
    db.pragma('journal_mode = WAL');
    initSchema(db);
  }
  return db;
}

function initSchema(db: Database.Database): void {
  db.exec(`
    CREATE TABLE IF NOT EXISTS watched_items (
      id INTEGER PRIMARY KEY AUTOINCREMENT,
      url TEXT NOT NULL UNIQUE,
      name TEXT,
      thumbnail_url TEXT,
      check_interval INTEGER NOT NULL DEFAULT 60,
      is_active INTEGER NOT NULL DEFAULT 1,
      last_status TEXT NOT NULL DEFAULT 'unknown',
      alert_sent INTEGER NOT NULL DEFAULT 0,
      check_count INTEGER NOT NULL DEFAULT 0,
      last_checked_at TEXT,
      created_at TEXT NOT NULL DEFAULT (datetime('now'))
    );

    CREATE TABLE IF NOT EXISTS settings (
      key TEXT PRIMARY KEY,
      value TEXT NOT NULL DEFAULT ''
    );

    INSERT OR IGNORE INTO settings (key, value) VALUES ('telegram_bot_token', '');
    INSERT OR IGNORE INTO settings (key, value) VALUES ('telegram_chat_id', '');
  `);
}

export type StockStatus = 'in_stock' | 'sold_out' | 'unknown';

export interface WatchedItem {
  id: number;
  url: string;
  name: string | null;
  thumbnail_url: string | null;
  check_interval: number;
  is_active: number;
  last_status: StockStatus;
  alert_sent: number;
  check_count: number;
  last_checked_at: string | null;
  created_at: string;
}