server.js

const express = require('express');
const { TwitterApi } = require('twitter-api-v2');
const axios = require('axios');
const fs = require('fs');
const path = require('path');
require('dotenv').config();

const app = express();
app.use(express.json({ limit: '50mb' }));

// Create uploads directory if it doesn't exist
const uploadsDir = path.join(__dirname, 'uploads');
if (!fs.existsSync(uploadsDir)) {
  fs.mkdirSync(uploadsDir);
}

// Twitter client
const twitterClient = new TwitterApi({
  appKey: process.env.TWITTER_API_KEY,
  appSecret: process.env.TWITTER_API_SECRET,
  accessToken: process.env.TWITTER_ACCESS_TOKEN,
  accessSecret: process.env.TWITTER_ACCESS_TOKEN_SECRET,
});

// Helper function to download image from URL
async function downloadImage(url, filepath) {
  const response = await axios({
    method: 'GET',
    url: url,
    responseType: 'stream'
  });
  
  return new Promise((resolve, reject) => {
    const stream = fs.createWriteStream(filepath);
    response.data.pipe(stream);
    stream.on('finish', resolve);
    stream.on('error', reject);
  });
}

// Health check
app.get('/health', (req, res) => {
  res.json({ status: 'OK', service: 'Twitter API Server' });
});

// Post to Twitter
app.post('/api/twitter/post', async (req, res) => {
  try {
    const { content, hashtags, imageData } = req.body;

    if (!content) {
      return res.status(400).json({ error: 'Content is required' });
    }

    // Prepare tweet text
    let tweetText = content;
    if (hashtags && hashtags.length > 0) {
      const hashtagText = hashtags.map(tag => 
        tag.startsWith('#') ? tag : `#${tag}`
      ).join(' ');
      tweetText = `${content} ${hashtagText}`;
    }

    // Keep under 280 characters
    if (tweetText.length > 280) {
      tweetText = tweetText.substring(0, 277) + '...';
    }

    let mediaId = null;

    // Handle image if provided
    if (imageData) {
      try {
        let imagePath;
        
        if (imageData.startsWith('http')) {
          // Download image from URL
          imagePath = path.join(uploadsDir, `temp_${Date.now()}.jpg`);
          await downloadImage(imageData, imagePath);
        } else if (imageData.startsWith('data:image')) {
          // Handle base64 image
          const base64Data = imageData.replace(/^data:image\/\w+;base64,/, '');
          imagePath = path.join(uploadsDir, `temp_${Date.now()}.jpg`);
          fs.writeFileSync(imagePath, base64Data, 'base64');
        }

        if (imagePath && fs.existsSync(imagePath)) {
          // Upload image to Twitter
          mediaId = await twitterClient.v1.uploadMedia(imagePath);
          
          // Clean up temporary file
          fs.unlinkSync(imagePath);
        }
      } catch (imageError) {
        console.error('Error processing image:', imageError);
        // Continue without image if there's an error
      }
    }

    // Post tweet
    const tweetOptions = {
      text: tweetText
    };

    if (mediaId) {
      tweetOptions.media = { media_ids: [mediaId] };
    }

    const tweet = await twitterClient.v2.tweet(tweetOptions);

    res.json({
      success: true,
      tweet_id: tweet.data.id,
      text: tweetText,
      has_image: !!mediaId,
      url: `https://twitter.com/user/status/${tweet.data.id}`
    });

  } catch (error) {
    console.error('Twitter API Error:', error);
    res.status(500).json({
      error: 'Failed to post to Twitter',
      message: error.message
    });
  }
});

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Twitter API Server running on port ${PORT}`);
});