const path = require('path');
const Database = require('better-sqlite3');

const dbPath = process.env.DB_PATH
  ? path.resolve(process.env.DB_PATH)
  : path.join(__dirname, 'mail.db');

const db = new Database(dbPath);

db.pragma('journal_mode = WAL');

db.exec(`
  CREATE TABLE IF NOT EXISTS channels (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    name TEXT NOT NULL,
    code TEXT NOT NULL UNIQUE,
    imap_host TEXT NOT NULL,
    imap_port INTEGER NOT NULL,
    imap_secure INTEGER NOT NULL DEFAULT 1,
    smtp_host TEXT NOT NULL,
    smtp_port INTEGER NOT NULL,
    smtp_secure INTEGER NOT NULL DEFAULT 1,
    created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP
  );

  CREATE TABLE IF NOT EXISTS accounts (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    channel_id INTEGER NOT NULL,
    email TEXT NOT NULL UNIQUE,
    auth_code TEXT NOT NULL,
    display_name TEXT,
    created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY(channel_id) REFERENCES channels(id)
  );

  CREATE TABLE IF NOT EXISTS mail_cache (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    account_id INTEGER NOT NULL,
    uid TEXT NOT NULL,
    folder TEXT NOT NULL DEFAULT 'INBOX',
    subject TEXT,
    from_name TEXT,
    from_address TEXT,
    to_addresses TEXT,
    sent_at TEXT,
    text_content TEXT,
    html_content TEXT,
    raw_json TEXT NOT NULL,
    created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
    UNIQUE(account_id, uid),
    FOREIGN KEY(account_id) REFERENCES accounts(id)
  );
`);

const seedChannels = [
  {
    name: 'QQ邮箱',
    code: 'qq',
    imap_host: 'imap.qq.com',
    imap_port: 993,
    imap_secure: 1,
    smtp_host: 'smtp.qq.com',
    smtp_port: 465,
    smtp_secure: 1,
  },
  {
    name: '163邮箱',
    code: '163',
    imap_host: 'imap.163.com',
    imap_port: 993,
    imap_secure: 1,
    smtp_host: 'smtp.163.com',
    smtp_port: 465,
    smtp_secure: 1,
  },
];

const channelExistsStmt = db.prepare('SELECT id FROM channels WHERE code = ?');
const insertChannelStmt = db.prepare(`
  INSERT INTO channels (
    name, code, imap_host, imap_port, imap_secure, smtp_host, smtp_port, smtp_secure
  ) VALUES (
    @name, @code, @imap_host, @imap_port, @imap_secure, @smtp_host, @smtp_port, @smtp_secure
  )
`);

for (const channel of seedChannels) {
  if (!channelExistsStmt.get(channel.code)) {
    insertChannelStmt.run(channel);
  }
}

module.exports = db;