const archiver = require('archiver');
const fs = require('fs').promises;
const path = require('path');
const { db } = require('../database/db');
const logger = require('../utils/logger');

const ACTIVE_PATH = path.join(__dirname, '../../../storage/events/active');
const ARCHIVE_PATH = path.join(__dirname, '../../../storage/events/archived');

async function archiveEvent(event) {
  try {
    const eventPath = path.join(ACTIVE_PATH, event.slug);
    const archiveName = `${event.slug}.zip`;
    const archivePath = path.join(ARCHIVE_PATH, archiveName);
    
    // Ensure archive directory exists
    await fs.mkdir(ARCHIVE_PATH, { recursive: true });
    
    // Create archive
    const output = require('fs').createWriteStream(archivePath);
    const archive = archiver('zip', {
      zlib: { level: 9 } // Maximum compression
    });
    
    archive.on('error', (err) => {
      throw err;
    });
    
    output.on('close', async () => {
      logger.info(`Archive created: ${archiveName} (${archive.pointer()} bytes)`);
      
      // Update database
      await db('events').where('id', event.id).update({
        is_archived: true,
        archive_path: path.relative(path.join(__dirname, '../../../storage'), archivePath),
        archived_at: new Date()
      });
      
      // Delete original files
      await fs.rm(eventPath, { recursive: true });
      
      // Delete thumbnails
      const photos = await db('photos').where('event_id', event.id);
      for (const photo of photos) {
        if (photo.thumbnail_path) {
          const thumbPath = path.join(__dirname, '../../../storage', photo.thumbnail_path);
          await fs.unlink(thumbPath).catch(() => {}); // Ignore if already deleted
        }
      }
      
      // Queue completion email
      await db('email_queue').insert({
        event_id: event.id,
        recipient_email: event.admin_email,
        email_type: 'archive_complete',
        email_data: JSON.stringify({
          event_name: event.event_name,
          archive_size: archive.pointer()
        })
      });
    });
    
    archive.pipe(output);
    archive.directory(eventPath, false);
    await archive.finalize();
    
  } catch (error) {
    logger.error(`Error archiving event ${event.slug}:`, error);
    throw error;
  }
}

module.exports = { archiveEvent };