const { MongoClient } = require('mongodb');
const fs = require('fs');
const path = require('path');

const MONGODB_URI = 'mongodb://localhost/beanstalk';
const DB_DIR = path.join(__dirname, '../public/db');

async function importDatabase() {
  const client = new MongoClient(MONGODB_URI);
  
  try {
    console.log('Connecting to MongoDB...');
    await client.connect();
    
    const db = client.db();
    
    // Check if DB directory exists
    if (!fs.existsSync(DB_DIR)) {
      console.error(`Error: Database directory not found: ${DB_DIR}`);
      process.exit(1);
    }
    
    console.log('Reading JSON files...');
    const files = fs.readdirSync(DB_DIR).filter(file => file.endsWith('.json'));
    
    if (files.length === 0) {
      console.log('No JSON files found in the database directory.');
      return;
    }
    
    for (const file of files) {
      const collectionName = path.basename(file, '.json');
      const filePath = path.join(DB_DIR, file);
      
      console.log(`\nImporting collection: ${collectionName}`);
      
      try {
        const data = JSON.parse(fs.readFileSync(filePath, 'utf8'));
        
        if (!Array.isArray(data)) {
          console.log(`  ⚠️  Warning: ${file} does not contain an array. Skipping.`);
          continue;
        }
        
        // Drop existing collection
        await db.collection(collectionName).drop().catch(() => {});
        console.log(`  ✓ Dropped existing collection`);
        
        // Insert data
        if (data.length > 0) {
          const result = await db.collection(collectionName).insertMany(data);
          console.log(`  ✓ Inserted ${result.insertedCount} documents`);
        } else {
          console.log(`  ✓ Collection is empty`);
        }
        
      } catch (error) {
        console.error(`  ✗ Error importing ${file}:`, error.message);
      }
    }
    
    console.log('\nDatabase import completed successfully!');
    
  } catch (error) {
    console.error('Error importing database:', error);
    process.exit(1);
  } finally {
    await client.close();
  }
}

// Handle command line arguments
const args = process.argv.slice(2);
if (args.includes('--help') || args.includes('-h')) {
  console.log(`
Usage: node import-db.js [options]

Options:
  --help, -h     Show this help message

Description:
  Imports JSON files from public/db directory into MongoDB.
  Each JSON file corresponds to a collection with the same name (without .json extension).
  
  The script will:
  1. Drop existing collections
  2. Create new collections with the imported data
  3. Preserve all document structure and data
  `);
  process.exit(0);
}

importDatabase();