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

const dbPath = path.join(process.cwd(), 'data', 'database.sqlite');

export interface UserNotificationSettings {
  user_id: string;
  email_enabled: boolean;
  telegram_enabled: boolean;
  telegram_chat_id: string | null;
  created_at?: string;
  updated_at?: string;
}

/**
 * Get notification settings for a user
 * Returns default settings if not found
 */
export function getUserNotificationSettings(
  userId: string
): UserNotificationSettings {
  const db = new Database(dbPath);
  try {
    const stmt = db.prepare(`
      SELECT
        user_id,
        email_enabled,
        telegram_enabled,
        telegram_chat_id,
        created_at,
        updated_at
      FROM UserNotificationSettings
      WHERE user_id = ?
    `);

    const result = stmt.get(userId) as any;

    // Return defaults if no settings found
    if (!result) {
      return {
        user_id: userId,
        email_enabled: true,
        telegram_enabled: false,
        telegram_chat_id: null,
      };
    }

    // Convert SQLite integers to booleans
    return {
      user_id: result.user_id,
      email_enabled: result.email_enabled === 1,
      telegram_enabled: result.telegram_enabled === 1,
      telegram_chat_id: result.telegram_chat_id,
      created_at: result.created_at,
      updated_at: result.updated_at,
    };
  } finally {
    db.close();
  }
}

/**
 * Update notification settings for a user
 */
export function updateUserNotificationSettings(
  userId: string,
  settings: Partial<UserNotificationSettings>
): UserNotificationSettings {
  const db = new Database(dbPath);
  try {
    // Check if settings exist
    const existing = db
      .prepare('SELECT user_id FROM UserNotificationSettings WHERE user_id = ?')
      .get(userId);

    if (existing) {
      // Update existing
      const updates: string[] = [];
      const values: any[] = [];

      if (settings.email_enabled !== undefined) {
        updates.push('email_enabled = ?');
        values.push(settings.email_enabled ? 1 : 0);
      }
      if (settings.telegram_enabled !== undefined) {
        updates.push('telegram_enabled = ?');
        values.push(settings.telegram_enabled ? 1 : 0);
      }
      if (settings.telegram_chat_id !== undefined) {
        updates.push('telegram_chat_id = ?');
        values.push(settings.telegram_chat_id);
      }

      updates.push('updated_at = datetime(\'now\')');
      values.push(userId);

      const stmt = db.prepare(`
        UPDATE UserNotificationSettings
        SET ${updates.join(', ')}
        WHERE user_id = ?
      `);

      stmt.run(...values);
    } else {
      // Insert new
      const stmt = db.prepare(`
        INSERT INTO UserNotificationSettings (
          user_id,
          email_enabled,
          telegram_enabled,
          telegram_chat_id
        ) VALUES (?, ?, ?, ?)
      `);

      stmt.run(
        userId,
        settings.email_enabled !== undefined ? (settings.email_enabled ? 1 : 0) : 1,
        settings.telegram_enabled !== undefined ? (settings.telegram_enabled ? 1 : 0) : 0,
        settings.telegram_chat_id ?? null
      );
    }

    return getUserNotificationSettings(userId);
  } finally {
    db.close();
  }
}

/**
 * Initialize notification settings table
 */
export function initNotificationSettingsTable(): void {
  const db = new Database(dbPath);
  try {
    db.exec(`
      CREATE TABLE IF NOT EXISTS UserNotificationSettings (
        user_id TEXT PRIMARY KEY,
        email_enabled INTEGER DEFAULT 1,
        telegram_enabled INTEGER DEFAULT 0,
        telegram_chat_id TEXT,
        created_at TEXT DEFAULT (datetime('now')),
        updated_at TEXT DEFAULT (datetime('now')),

        FOREIGN KEY (user_id) REFERENCES User(id) ON DELETE CASCADE,
        CHECK (email_enabled IN (0, 1)),
        CHECK (telegram_enabled IN (0, 1))
      );

      CREATE INDEX IF NOT EXISTS idx_user_notification_settings_user
        ON UserNotificationSettings(user_id);
    `);

    console.log('✓ UserNotificationSettings table initialized');
  } finally {
    db.close();
  }
}