const mongoose = require('mongoose');
const Company = require('../models/Company');
require('dotenv').config({ path: '../../.env' });

const industryMap = {
  'it': 'IT',
  'finance': 'Финансы',
  'manufacturing': 'Производство',
  'construction': 'Строительство',
  'retail': 'Розничная торговля',
  'wholesale': 'Оптовая торговля',
  'logistics': 'Логистика',
  'healthcare': 'Здравоохранение',
  'education': 'Образование',
  'consulting': 'Консалтинг',
  'marketing': 'Маркетинг',
  'realestate': 'Недвижимость',
  'food': 'Пищевая промышленность',
  'agriculture': 'Сельское хозяйство',
  'energy': 'Энергетика',
  'telecom': 'Телекоммуникации',
  'media': 'Медиа',
  'tourism': 'Туризм',
  'legal': 'Юридические услуги',
  'other': 'Другое'
};

const validIndustries = Object.values(industryMap);

const industryAliases = {
  'Торговля': 'Розничная торговля',
  'торговля': 'Розничная торговля',
  'Trade': 'Розничная торговля'
};

async function migrateCompanies() {
  try {
    const allCompanies = await Company.find().exec();
    console.log(`[Migration] Found ${allCompanies.length} companies to process`);

    let fixedCount = 0;
    let errorCount = 0;

    for (const company of allCompanies) {
      let needsUpdate = false;
      let updates = {};

      // Check and fix industry field
      if (company.industry) {
        if (Array.isArray(company.industry)) {
          console.log(`[FIX] ${company.fullName}: industry is array, converting to string`);
          updates.industry = company.industry[0] || 'Другое';
          needsUpdate = true;
        } else if (!validIndustries.includes(company.industry)) {
          const mapped = industryAliases[company.industry];
          if (mapped) {
            console.log(`[FIX] ${company.fullName}: "${company.industry}" → "${mapped}"`);
            updates.industry = mapped;
            needsUpdate = true;
          } else {
            console.log(`[WARN] ${company.fullName}: unknown industry "${company.industry}"`);
          }
        }
      }

      // Check and fix companySize field
      if (company.companySize && Array.isArray(company.companySize)) {
        console.log(`[FIX] ${company.fullName}: companySize is array, converting to string`);
        updates.companySize = company.companySize[0] || '';
        needsUpdate = true;
      }

      if (needsUpdate) {
        try {
          await Company.updateOne({ _id: company._id }, { $set: updates });
          fixedCount++;
          console.log(`   ✅ Updated`);
        } catch (err) {
          console.error(`   ❌ Error: ${err.message}`);
          errorCount++;
        }
      }
    }

    console.log('\n[Migration] === MIGRATION SUMMARY ===');
    console.log(`[Migration] Total companies: ${allCompanies.length}`);
    console.log(`[Migration] Fixed: ${fixedCount}`);
    console.log(`[Migration] Errors: ${errorCount}`);

    if (fixedCount === 0 && errorCount === 0) {
      console.log('[Migration] ✅ No migration needed - all data is valid!');
    } else if (errorCount === 0) {
      console.log('[Migration] ✅ Migration completed successfully!');
    } else {
      console.log('[Migration] ⚠️  Migration completed with errors.');
    }
  } catch (err) {
    console.error('[Migration] ❌ Error:', err.message);
    throw err;
  }
}

module.exports = {
  migrateCompanies: migrateCompanies
};

// Run directly if called as script
if (require.main === module) {
  const mongoUrl = process.env.MONGODB_URI || 'mongodb://admin:password@localhost:27017/procurement_db?authSource=admin';
  
  mongoose.connect(mongoUrl, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
    serverSelectionTimeoutMS: 5000,
    connectTimeoutMS: 5000,
  }).then(async () => {
    console.log('[Migration] Connected to MongoDB\n');
    await migrateCompanies();
    await mongoose.connection.close();
  }).catch(err => {
    console.error('[Migration] ❌ Error:', err.message);
    process.exit(1);
  });
}