const mongoose = require('mongoose');
const { migrateCompanies } = require('./migrate-companies');
const { migrateMessages } = require('./migrate-messages');
const { recreateTestUser } = require('./recreate-test-user');
require('dotenv').config();

const mongoUrl = process.env.MONGODB_URI || 'mongodb://admin:password@localhost:27017/procurement_db?authSource=admin';

// Migration history model
const migrationSchema = new mongoose.Schema({
  name: { type: String, unique: true, required: true },
  executedAt: { type: Date, default: Date.now },
  status: { type: String, enum: ['completed', 'failed'], default: 'completed' },
  message: String
}, { collection: 'migrations' });

const Migration = mongoose.model('Migration', migrationSchema);

const migrations = [
  { name: 'migrate-companies', fn: migrateCompanies },
  { name: 'migrate-messages', fn: migrateMessages },
  { name: 'recreate-test-user', fn: recreateTestUser }
];

async function runMigrations(shouldCloseConnection = false) {
  let mongooseConnected = false;

  try {
    console.log('\n' + '='.repeat(60));
    console.log('🚀 Starting Database Migrations');
    console.log('='.repeat(60) + '\n');

    // Only connect if not already connected
    if (mongoose.connection.readyState === 0) {
      console.log('[Migrations] Connecting to MongoDB...');
      await mongoose.connect(mongoUrl, {
        useNewUrlParser: true,
        useUnifiedTopology: true,
        serverSelectionTimeoutMS: 5000,
        connectTimeoutMS: 5000,
      });
      mongooseConnected = true;
      console.log('[Migrations] ✅ Connected to MongoDB\n');
    } else {
      console.log('[Migrations] ✅ Using existing MongoDB connection\n');
    }

    for (const migration of migrations) {
      console.log(`[${migration.name}] Starting...`);
      
      try {
        // Check if already executed
        const existing = await Migration.findOne({ name: migration.name });

        if (existing) {
          console.log(`[${migration.name}] ℹ️  Already executed at: ${existing.executedAt.toISOString()}`);
          console.log(`[${migration.name}] Status: ${existing.status}`);
          if (existing.message) console.log(`[${migration.name}] Message: ${existing.message}`);
          console.log('');
          continue;
        }

        // Run migration
        await migration.fn();

        // Record successful migration
        await Migration.create({
          name: migration.name,
          status: 'completed',
          message: `${migration.name} executed successfully`
        });

        console.log(`[${migration.name}] ✅ Completed and recorded\n`);
      } catch (error) {
        console.error(`[${migration.name}] ❌ Error: ${error.message}\n`);

        // Record failed migration
        try {
          await Migration.create({
            name: migration.name,
            status: 'failed',
            message: error.message
          });
        } catch (recordErr) {
          // Ignore if we can't record the failure
        }
      }
    }

    console.log('='.repeat(60));
    console.log('✅ All migrations processed');
    console.log('='.repeat(60) + '\n');

  } catch (error) {
    console.error('\n❌ Fatal migration error:', error.message);
    console.error(error);
    if (shouldCloseConnection) {
      process.exit(1);
    }
  } finally {
    // Only close connection if we created it and requested to close
    if (mongooseConnected && shouldCloseConnection) {
      await mongoose.connection.close();
      console.log('[Migrations] Disconnected from MongoDB\n');
    }
  }
}

module.exports = { runMigrations, Migration };

// Run directly if called as script
if (require.main === module) {
  runMigrations(true).catch(err => {
    console.error('Migration failed:', err);
    process.exit(1);
  });
}