#!/usr/bin/env node

import fs from 'fs/promises';
import path from 'path';
import { fileURLToPath } from 'url';
import mongoose from 'mongoose';
import dotenv from 'dotenv';

// Load environment variables
dotenv.config({ path: '.env.local' });

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

// MongoDB connection URI
const MONGODB_URI = process.env.MONGODB_URI || 'mongodb://localhost:27017/witlab-funnel';

// Mongoose schemas (inline for the script)
const FunnelDataSchema = new mongoose.Schema({
  meta: {
    id: { type: String, required: true },
    version: String,
    title: String,
    description: String,
    firstScreenId: String
  },
  defaultTexts: {
    nextButton: { type: String, default: 'Next' },
    continueButton: { type: String, default: 'Continue' }
  },
  screens: [mongoose.Schema.Types.Mixed]
}, { _id: false });

const FunnelSchema = new mongoose.Schema({
  // Основные данные воронки
  funnelData: { 
    type: FunnelDataSchema, 
    required: true
  },
  
  // Метаданные для админки
  name: { 
    type: String, 
    required: true,
    trim: true,
    maxlength: 200
  },
  description: {
    type: String,
    trim: true,
    maxlength: 1000
  },
  status: { 
    type: String, 
    enum: ['draft', 'published', 'archived'],
    default: 'published', // Импортированные воронки считаем опубликованными
    required: true
  },
  
  // Система версий
  version: { 
    type: Number, 
    default: 1,
    min: 1
  },
  
  // Пользовательские данные
  createdBy: { type: String, default: 'import-script' },
  lastModifiedBy: { type: String, default: 'import-script' },
  
  // Статистика
  usage: {
    totalViews: { type: Number, default: 0, min: 0 },
    totalCompletions: { type: Number, default: 0, min: 0 },
    lastUsed: Date
  },
  
  // Timestamps
  publishedAt: { type: Date, default: Date.now }
}, {
  timestamps: true,
  collection: 'funnels'
});

// Индексы
FunnelSchema.index({ 'funnelData.meta.id': 1 }, { unique: true });
FunnelSchema.index({ status: 1, updatedAt: -1 });

const FunnelModel = mongoose.models.Funnel || mongoose.model('Funnel', FunnelSchema);

// Utility functions
function generateFunnelName(funnelData) {
  // Пытаемся получить имя из разных источников
  if (funnelData.meta?.title) {
    return funnelData.meta.title;
  }
  
  if (funnelData.meta?.id) {
    // Преобразуем ID в читаемое название
    return funnelData.meta.id
      .split('-')
      .map(word => word.charAt(0).toUpperCase() + word.slice(1))
      .join(' ');
  }
  
  return 'Imported Funnel';
}

function generateFunnelDescription(funnelData) {
  if (funnelData.meta?.description) {
    return funnelData.meta.description;
  }
  
  // Генерируем описание на основе количества экранов
  const screenCount = funnelData.screens?.length || 0;
  const templates = funnelData.screens?.map(s => s.template).filter(Boolean) || [];
  const uniqueTemplates = [...new Set(templates)];
  
  return `Воронка с ${screenCount} экран${screenCount === 1 ? 'ом' : screenCount < 5 ? 'ами' : 'ами'}.${
    uniqueTemplates.length > 0 ? ` Типы: ${uniqueTemplates.join(', ')}.` : ''
  } Импортирована из JSON файла.`;
}

async function connectToDatabase() {
  try {
    await mongoose.connect(MONGODB_URI, {
      bufferCommands: false,
      maxPoolSize: 10,
      serverSelectionTimeoutMS: 5000,
      socketTimeoutMS: 45000,
    });
    console.log('✅ Connected to MongoDB');
  } catch (error) {
    console.error('❌ Failed to connect to MongoDB:', error.message);
    process.exit(1);
  }
}

async function findFunnelFiles() {
  const funnelsDir = path.join(__dirname, '..', 'public', 'funnels');
  
  try {
    const files = await fs.readdir(funnelsDir);
    const jsonFiles = files.filter(file => file.endsWith('.json'));
    
    console.log(`📁 Found ${jsonFiles.length} funnel files in public/funnels/`);
    
    return jsonFiles.map(file => ({
      filename: file,
      filepath: path.join(funnelsDir, file)
    }));
  } catch (error) {
    console.error('❌ Failed to read funnels directory:', error.message);
    process.exit(1);
  }
}

async function validateFunnelData(funnelData, filename) {
  const errors = [];
  
  if (!funnelData) {
    errors.push('Empty funnel data');
  }
  
  if (!funnelData.meta) {
    errors.push('Missing meta object');
  } else {
    if (!funnelData.meta.id) {
      errors.push('Missing meta.id');
    }
  }
  
  if (!funnelData.screens) {
    errors.push('Missing screens array');
  } else if (!Array.isArray(funnelData.screens)) {
    errors.push('screens is not an array');
  } else if (funnelData.screens.length === 0) {
    errors.push('Empty screens array');
  }
  
  if (errors.length > 0) {
    console.warn(`⚠️  Validation warnings for ${filename}:`, errors);
    return false;
  }
  
  return true;
}

async function importFunnel(funnelFile) {
  const { filename, filepath } = funnelFile;
  
  try {
    // Читаем и парсим JSON файл
    const fileContent = await fs.readFile(filepath, 'utf-8');
    const funnelData = JSON.parse(fileContent);
    
    // Валидируем структуру данных
    if (!validateFunnelData(funnelData, filename)) {
      return { filename, status: 'skipped', reason: 'Invalid data structure' };
    }
    
    // Проверяем, существует ли уже воронка с таким ID
    const existingFunnel = await FunnelModel.findOne({ 
      'funnelData.meta.id': funnelData.meta.id 
    });
    
    if (existingFunnel) {
      return { 
        filename, 
        status: 'exists', 
        funnelId: funnelData.meta.id,
        reason: 'Funnel with this ID already exists in database'
      };
    }
    
    // Создаем новую запись в базе данных
    const funnel = new FunnelModel({
      funnelData: funnelData,
      name: generateFunnelName(funnelData),
      description: generateFunnelDescription(funnelData),
      status: 'published',
      version: 1,
      createdBy: 'import-script',
      lastModifiedBy: 'import-script',
      usage: {
        totalViews: 0,
        totalCompletions: 0
      },
      publishedAt: new Date()
    });
    
    const savedFunnel = await funnel.save();
    
    return { 
      filename, 
      status: 'imported', 
      funnelId: funnelData.meta.id,
      databaseId: savedFunnel._id.toString(),
      name: savedFunnel.name
    };
    
  } catch (error) {
    return { 
      filename, 
      status: 'error', 
      reason: error.message 
    };
  }
}

async function main() {
  console.log('🚀 Starting funnel import process...\n');
  
  // Подключаемся к базе данных
  await connectToDatabase();
  
  // Находим все JSON файлы воронок
  const funnelFiles = await findFunnelFiles();
  
  if (funnelFiles.length === 0) {
    console.log('📭 No funnel files found to import.');
    process.exit(0);
  }
  
  console.log(`\n📥 Starting import of ${funnelFiles.length} funnels...\n`);
  
  // Импортируем каждую воронку
  const results = [];
  
  for (let i = 0; i < funnelFiles.length; i++) {
    const funnelFile = funnelFiles[i];
    const progress = `[${i + 1}/${funnelFiles.length}]`;
    
    console.log(`${progress} Processing ${funnelFile.filename}...`);
    
    const result = await importFunnel(funnelFile);
    results.push(result);
    
    // Показываем результат
    switch (result.status) {
      case 'imported':
        console.log(`  ✅ Imported as "${result.name}" (ID: ${result.funnelId})`);
        break;
      case 'exists':
        console.log(`  ⏭️  Skipped - already exists (ID: ${result.funnelId})`);
        break;
      case 'skipped':
        console.log(`  ⚠️  Skipped - ${result.reason}`);
        break;
      case 'error':
        console.log(`  ❌ Error - ${result.reason}`);
        break;
    }
  }
  
  // Показываем сводку
  console.log('\n📊 Import Summary:');
  console.log('==================');
  
  const imported = results.filter(r => r.status === 'imported');
  const existing = results.filter(r => r.status === 'exists');
  const skipped = results.filter(r => r.status === 'skipped');
  const errors = results.filter(r => r.status === 'error');
  
  console.log(`✅ Successfully imported: ${imported.length}`);
  console.log(`⏭️  Already existed: ${existing.length}`);
  console.log(`⚠️  Skipped (invalid): ${skipped.length}`);
  console.log(`❌ Errors: ${errors.length}`);
  console.log(`📁 Total processed: ${results.length}`);
  
  // Показываем детальную информацию об импортированных воронках
  if (imported.length > 0) {
    console.log('\n📋 Imported Funnels:');
    imported.forEach(result => {
      console.log(`  • ${result.name} (${result.funnelId}) - ${result.filename}`);
    });
  }
  
  // Показываем ошибки
  if (errors.length > 0) {
    console.log('\n❌ Errors:');
    errors.forEach(result => {
      console.log(`  • ${result.filename}: ${result.reason}`);
    });
  }
  
  // Показываем пропущенные
  if (skipped.length > 0) {
    console.log('\n⚠️  Skipped:');
    skipped.forEach(result => {
      console.log(`  • ${result.filename}: ${result.reason}`);
    });
  }
  
  console.log('\n🎉 Import process completed!');
  
  // Показываем следующие шаги
  if (imported.length > 0) {
    console.log('\n📌 Next Steps:');
    console.log('• Visit /admin to manage your funnels');
    console.log('• Imported funnels are marked as "published"');
    console.log('• You can edit them in /admin/builder/[id]');
    console.log('• Original JSON files remain unchanged');
  }
  
  await mongoose.connection.close();
  console.log('\n👋 Database connection closed.');
}

// Запускаем скрипт
main().catch(error => {
  console.error('\n💥 Fatal error:', error);
  process.exit(1);
});