require('dotenv').config();
const fs = require('fs').promises;
const path = require('path');
const mongoose = require('mongoose');
const connectDB = require('../config/database');
const Programme = require('../models/programme');

async function validateProgrammeData(dataArray) {
  if (!Array.isArray(dataArray)) {
    throw new Error('Data must be an array of programme objects');
  }
  
  if (dataArray.length === 0) {
    throw new Error('Programme array cannot be empty');
  }

  for (const item of dataArray) {
    if (!item.id || !item.title || !item.level) {
      throw new Error(`Programme is missing required fields (id, title, level). Error at id: ${item.id}`);
    }
  }
}

async function migrateProgrammeData() {
  try {
    await connectDB();
    console.log('Đã kết nối đến MongoDB...');

    await Programme.deleteMany({});
    console.log('Đã xóa dữ liệu Programme cũ');

    const programmesData = JSON.parse(
      await fs.readFile(path.join(__dirname, '../data/programmes.json'), 'utf8')
    );

    await validateProgrammeData(programmesData);

    const dataWithTimestamps = programmesData.map(item => ({
      ...item,
      updatedAt: new Date()
    }));

    await Programme.insertMany(dataWithTimestamps);
    console.log(`✓ Migrate dữ liệu Programmes thành công (${dataWithTimestamps.length} items)!`);
    process.exit(0);

  } catch (error) {
    console.error('Lỗi:', error.message);
    process.exit(1);
  }
}

migrateProgrammeData();