import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import mysql from 'mysql2/promise';
import dotenv from 'dotenv';
import bcrypt from 'bcryptjs';

// 載入環境變數
dotenv.config();

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

// 資料庫配置
const dbConfig = {
  host: process.env.DB_HOST || 'mysql.theaken.com',
  port: parseInt(process.env.DB_PORT) || 33306,
  user: process.env.DB_USER || 'A102',
  password: process.env.DB_PASSWORD || 'Bb123456',
  database: process.env.DB_NAME || 'db_A102',
  multipleStatements: true
};

async function initDatabase() {
  let connection;

  try {
    console.log('🔄 Connecting to database...');
    console.log(`   Host: ${dbConfig.host}:${dbConfig.port}`);
    console.log(`   Database: ${dbConfig.database}`);

    connection = await mysql.createConnection(dbConfig);
    console.log('✅ Connected successfully\n');

    // 讀取 SQL 檔案
    const sqlPath = path.join(__dirname, '../docs/db_schema.sql');
    console.log('📖 Reading SQL file:', sqlPath);

    let sqlContent = fs.readFileSync(sqlPath, 'utf8');

    // 生成管理者密碼 hash
    const adminPassword = process.env.ADMIN_PASSWORD || 'Admin@123456';
    const adminHash = await bcrypt.hash(adminPassword, 10);

    console.log('🔐 Generated admin password hash');

    // 替換 SQL 中的密碼 hash
    sqlContent = sqlContent.replace(/\$2a\$10\$YourBcryptHashHere/g, adminHash);

    // 分割 SQL 語句
    const statements = sqlContent
      .split(';')
      .map(stmt => stmt.trim())
      .filter(stmt => stmt.length > 0 && !stmt.startsWith('--'));

    console.log(`\n📝 Found ${statements.length} SQL statements\n`);

    // 執行每個語句
    for (let i = 0; i < statements.length; i++) {
      const statement = statements[i];

      // 跳過註解和空白
      if (statement.startsWith('--') || statement.trim() === '') {
        continue;
      }

      try {
        // 顯示正在執行的語句類型
        let action = 'Executing';
        if (statement.toUpperCase().includes('CREATE TABLE')) {
          const match = statement.match(/CREATE TABLE(?:\s+IF NOT EXISTS)?\s+`?(\w+)`?/i);
          if (match) {
            action = `Creating table: ${match[1]}`;
          }
        } else if (statement.toUpperCase().includes('CREATE VIEW')) {
          const match = statement.match(/CREATE.*VIEW\s+`?(\w+)`?/i);
          if (match) {
            action = `Creating view: ${match[1]}`;
          }
        } else if (statement.toUpperCase().includes('INSERT INTO')) {
          const match = statement.match(/INSERT INTO\s+`?(\w+)`?/i);
          if (match) {
            action = `Inserting data into: ${match[1]}`;
          }
        }

        console.log(`   [${i + 1}/${statements.length}] ${action}`);
        await connection.execute(statement);
      } catch (error) {
        // 如果是 "already exists" 錯誤，只顯示警告
        if (error.message.includes('already exists')) {
          console.log(`   ⚠️  Already exists, skipping...`);
        } else {
          console.error(`   ❌ Error: ${error.message}`);
        }
      }
    }

    console.log('\n✅ Database initialization completed successfully!\n');

    // 顯示建立的資料表
    const [tables] = await connection.execute('SHOW TABLES');
    console.log('📊 Tables in database:');
    tables.forEach((table, index) => {
      const tableName = Object.values(table)[0];
      console.log(`   ${index + 1}. ${tableName}`);
    });

    console.log('\n🔐 Default admin credentials:');
    console.log(`   Email: ${process.env.ADMIN_EMAIL || 'admin@example.com'}`);
    console.log(`   Password: ${adminPassword}`);
    console.log('\n⚠️  Please change the admin password after first login!\n');

  } catch (error) {
    console.error('\n❌ Database initialization failed:');
    console.error('   Error:', error.message);
    if (error.code) {
      console.error('   Error Code:', error.code);
    }
    process.exit(1);
  } finally {
    if (connection) {
      await connection.end();
      console.log('🔌 Database connection closed\n');
    }
  }
}

// 執行初始化
console.log('\n╔════════════════════════════════════════════╗');
console.log('║  5 Why Analyzer - Database Initialization ║');
console.log('╚════════════════════════════════════════════╝\n');

initDatabase();