const fs = require('fs');
const path = require('path');
const https = require('https');

// Configuration
const FILES = [
  {
    name: '39f2x83-products.csv',
    url: 'https://feeds.acherryontop.com/39f2x83-products.csv'
  },
  {
    name: '39f2x83-orders.csv',
    url: 'https://feeds.acherryontop.com/39f2x83-orders.csv'
  },
  {
    name: '39f2x83-purchase_orders.csv',
    url: 'https://feeds.acherryontop.com/39f2x83-purchase_orders.csv'
  }
];

const CSV_DIR = path.join(__dirname, '..', 'csv');

// Ensure CSV directory exists
if (!fs.existsSync(CSV_DIR)) {
  fs.mkdirSync(CSV_DIR, { recursive: true });
}

// Function to download a file
function downloadFile(url, filePath) {
  return new Promise((resolve, reject) => {
    const file = fs.createWriteStream(filePath);
    
    https.get(url, response => {
      if (response.statusCode !== 200) {
        reject(new Error(`Failed to download: ${response.statusCode} ${response.statusMessage}`));
        return;
      }

      const totalSize = parseInt(response.headers['content-length'], 10);
      let downloadedSize = 0;
      let lastProgressUpdate = Date.now();
      const startTime = Date.now();

      response.on('data', chunk => {
        downloadedSize += chunk.length;
        const now = Date.now();
        // Update progress at most every 100ms to avoid console flooding
        if (now - lastProgressUpdate > 100) {
          const elapsed = (now - startTime) / 1000;
          const rate = downloadedSize / elapsed;
          const remaining = (totalSize - downloadedSize) / rate;
          
          console.log(JSON.stringify({
            status: 'running',
            operation: `Downloading ${path.basename(filePath)}`,
            current: downloadedSize,
            total: totalSize,
            rate: (rate / 1024 / 1024).toFixed(2), // MB/s
            elapsed: formatDuration(elapsed),
            remaining: formatDuration(remaining),
            percentage: ((downloadedSize / totalSize) * 100).toFixed(1)
          }));
          lastProgressUpdate = now;
        }
      });

      response.pipe(file);

      file.on('finish', () => {
        console.log(JSON.stringify({
          status: 'running',
          operation: `Completed ${path.basename(filePath)}`,
          current: totalSize,
          total: totalSize,
          percentage: '100'
        }));
        file.close();
        resolve();
      });
    }).on('error', error => {
      fs.unlink(filePath, () => {}); // Delete the file if download failed
      reject(error);
    });

    file.on('error', error => {
      fs.unlink(filePath, () => {}); // Delete the file if there was an error
      reject(error);
    });
  });
}

// Helper function to format duration
function formatDuration(seconds) {
  if (seconds < 60) return `${Math.round(seconds)}s`;
  const minutes = Math.floor(seconds / 60);
  seconds = Math.round(seconds % 60);
  return `${minutes}m ${seconds}s`;
}

// Main function to update all files
async function updateFiles() {
  console.log(JSON.stringify({
    status: 'running',
    operation: 'Starting CSV file updates',
    total: FILES.length,
    current: 0
  }));

  for (let i = 0; i < FILES.length; i++) {
    const file = FILES[i];
    const filePath = path.join(CSV_DIR, file.name);
    
    try {
      // Delete existing file if it exists
      if (fs.existsSync(filePath)) {
        console.log(JSON.stringify({
          status: 'running',
          operation: `Removing existing file: ${file.name}`,
          current: i,
          total: FILES.length,
          percentage: ((i / FILES.length) * 100).toFixed(1)
        }));
        fs.unlinkSync(filePath);
      }

      // Download new file
      console.log(JSON.stringify({
        status: 'running',
        operation: `Starting download: ${file.name}`,
        current: i,
        total: FILES.length,
        percentage: ((i / FILES.length) * 100).toFixed(1)
      }));
      await downloadFile(file.url, filePath);
      console.log(JSON.stringify({
        status: 'running',
        operation: `Successfully updated ${file.name}`,
        current: i + 1,
        total: FILES.length,
        percentage: (((i + 1) / FILES.length) * 100).toFixed(1)
      }));
    } catch (error) {
      console.error(JSON.stringify({
        status: 'error',
        operation: `Error updating ${file.name}`,
        error: error.message
      }));
      throw error;
    }
  }

  console.log(JSON.stringify({
    status: 'complete',
    operation: 'CSV file update complete',
    current: FILES.length,
    total: FILES.length,
    percentage: '100'
  }));
}

// Run the update
updateFiles().catch(error => {
  console.error(JSON.stringify({
    error: `Update failed: ${error.message}`
  }));
  process.exit(1);
});