import mysql from 'mysql2/promise';
import dotenv from 'dotenv';

dotenv.config();

const { DB_HOST, DB_USER, DB_PASS, DB_NAME, DB_PORT } = process.env;

async function migrateSchema() {
  const connection = await mysql.createConnection({
    host: DB_HOST,
    user: DB_USER,
    password: DB_PASS,
    database: DB_NAME,
    port: parseInt(DB_PORT || '3306')
  });

  console.log('🚀 Phase 1: Creating Normalized Tables & Migrating Data...');

  try {
    await connection.query('SET FOREIGN_KEY_CHECKS = 0');

    // --- 1. Drop existing new tables if they exist ---
    await connection.query('DROP TABLE IF EXISTS asset_core, asset_hardware, asset_location, asset_remote');

    // --- 2. Create New Schema ---
    await connection.query(`
      CREATE TABLE asset_core (
        id VARCHAR(50) PRIMARY KEY,
        asset_code VARCHAR(100) UNIQUE NOT NULL,
        category VARCHAR(100),
        asset_type VARCHAR(100),
        asset_purpose VARCHAR(255),
        service_type VARCHAR(50),
        purchase_corp VARCHAR(100),
        purchase_date VARCHAR(50),
        purchase_amount VARCHAR(100),
        purchase_vendor VARCHAR(255),
        approval_document VARCHAR(255),
        memo TEXT,
        manager_primary VARCHAR(100),
        manager_secondary VARCHAR(100),
        current_dept VARCHAR(255),
        previous_dept VARCHAR(255),
        user_current VARCHAR(100),
        previous_user VARCHAR(100),
        emp_no VARCHAR(20),
        user_position VARCHAR(50),
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
      ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
    `);

    await connection.query(`
      CREATE TABLE asset_hardware (
        id INT AUTO_INCREMENT PRIMARY KEY,
        asset_id VARCHAR(50) NOT NULL,
        hw_status VARCHAR(50),
        model_name VARCHAR(255),
        mainboard VARCHAR(255),
        os VARCHAR(100),
        cpu VARCHAR(255),
        ram VARCHAR(100),
        gpu VARCHAR(100),
        storage1 VARCHAR(255),
        storage2 VARCHAR(255),
        storage3 VARCHAR(255),
        monitoring VARCHAR(100),
        price VARCHAR(100),
        volume VARCHAR(100),
        monitor_inch VARCHAR(50),
        serial_num VARCHAR(100),
        FOREIGN KEY (asset_id) REFERENCES asset_core(id) ON DELETE CASCADE
      ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
    `);

    await connection.query(`
      CREATE TABLE asset_location (
        id INT AUTO_INCREMENT PRIMARY KEY,
        asset_id VARCHAR(50) NOT NULL,
        location VARCHAR(255),
        location_detail VARCHAR(255),
        location_photo VARCHAR(255),
        loc_x VARCHAR(20),
        loc_y VARCHAR(20),
        is_active BOOLEAN DEFAULT TRUE,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        FOREIGN KEY (asset_id) REFERENCES asset_core(id) ON DELETE CASCADE
      ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
    `);

    await connection.query(`
      CREATE TABLE asset_remote (
        id INT AUTO_INCREMENT PRIMARY KEY,
        asset_id VARCHAR(50) NOT NULL,
        ip_address VARCHAR(100),
        mac_address VARCHAR(100),
        remote_tool VARCHAR(100),
        remote_id VARCHAR(100),
        remote_pw VARCHAR(100),
        is_active BOOLEAN DEFAULT TRUE,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
        FOREIGN KEY (asset_id) REFERENCES asset_core(id) ON DELETE CASCADE
      ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
    `);

    await connection.query('SET FOREIGN_KEY_CHECKS = 1');
    console.log('✅ Normalized tables created.');

    // --- 3. Migrate Data from Legacy Tables ---
    const legacyTables = ['asset_pc', 'asset_server', 'asset_storage', 'asset_remote', 'asset_equipment', 'asset_office_supplies', 'asset_survey', 'asset_vip'];
    
    let totalMigrated = 0;

    for (const table of legacyTables) {
      try {
        const [rows] = await connection.query(`SELECT * FROM ${table}`);
        
        for (const row of rows) {
          // 3.1 Insert into asset_core
          await connection.query(`
            INSERT IGNORE INTO asset_core (
              id, asset_code, category, asset_type, asset_purpose, service_type, purchase_corp, purchase_date, 
              purchase_amount, purchase_vendor, approval_document, memo, manager_primary, manager_secondary, 
              current_dept, previous_dept, user_current, previous_user, emp_no, user_position, created_at
            ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
          `, [
            row.id, row.asset_code, row.category, row.asset_type, row.asset_purpose, row.service_type, 
            row.purchase_corp, row.purchase_date, row.purchase_amount, row.purchase_vendor, row.approval_document, 
            row.memo, row.manager_primary, row.manager_secondary, row.current_dept, row.previous_dept, 
            row.user_current, row.previous_user, row.emp_no, row.user_position, row.created_at
          ]);

          // 3.2 Insert into asset_hardware (if hardware fields exist)
          if (row.model_name || row.cpu || row.ram || row.hw_status) {
              await connection.query(`
                INSERT INTO asset_hardware (
                  asset_id, hw_status, model_name, mainboard, os, cpu, ram, gpu, storage1, storage2, storage3, monitoring, price, volume, monitor_inch, serial_num
                ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
              `, [
                row.id, row.hw_status, row.model_name, row.mainboard, row.os, row.cpu, row.ram, row.gpu, 
                row.ssd_1 || row.hdd_1, row.ssd_2 || row.hdd_2, row.hdd_3, row.monitoring, row.price, 
                row.volume, row.monitor_inch, row.serial_num
              ]);
          }

          // 3.3 Insert into asset_location (if location fields exist)
          if (row.location || row.location_detail) {
              await connection.query(`
                INSERT INTO asset_location (
                  asset_id, location, location_detail, location_photo, loc_x, loc_y
                ) VALUES (?, ?, ?, ?, ?, ?)
              `, [
                row.id, row.location, row.location_detail, row.location_photo, row.loc_x, row.loc_y
              ]);
          }

          // 3.4 Insert into asset_remote (if network fields exist)
          // Handle primary network interface
          if (row.ip_address || row.mac_address || row.remote_tool) {
              await connection.query(`
                INSERT INTO asset_remote (
                  asset_id, ip_address, mac_address, remote_tool, remote_id, remote_pw
                ) VALUES (?, ?, ?, ?, ?, ?)
              `, [
                row.id, row.ip_address, row.mac_address, row.remote_tool, row.remote_id, row.remote_pw
              ]);
          }
          
          // Handle secondary network interface (e.g., from server table) if it exists
          if (row.ip_address_2 || row.remote_tool_2) {
              await connection.query(`
                INSERT INTO asset_remote (
                  asset_id, ip_address, remote_tool, remote_id, remote_pw
                ) VALUES (?, ?, ?, ?, ?)
              `, [
                row.id, row.ip_address_2, row.remote_tool_2, row.remote_id_2, row.remote_pw_2
              ]);
          }

          totalMigrated++;
        }
        console.log(`- Migrated ${rows.length} records from ${table}`);
      } catch (err) {
        console.warn(`- Skipping legacy table ${table}: ${err.message}`);
      }
    }

    console.log(`✅ Phase 1 Data Migration Completed. Total Assets Migrated: ${totalMigrated}`);

  } catch (err) {
    console.error('❌ Migration Failed:', err);
  } finally {
    await connection.end();
  }
}

migrateSchema();