const express = require('express');
const router = express.Router();
const database = require('../lib/database');
const storage = require('../lib/storage');
const imageFetcher = require('../lib/image-fetcher');

/**
 * GET /api/images - Get all images with optional filtering
 */
router.get('/images', async (req, res) => {
  try {
    const { tag, sourceUrl, page = 1, pageSize = 50, sort = 'fetched_at', order = 'DESC' } = req.query;
    
    const limit = parseInt(pageSize);
    const offset = (parseInt(page) - 1) * limit;

    const images = await database.getImages({
      tag,
      sourceUrl,
      limit,
      offset,
      sortBy: sort,
      order
    });

    // Get tags for each image
    for (let i = 0; i < images.length; i++) {
      images[i].tags = await database.getImageTags(images[i].id);
    }

    const total = await database.getImageCount(tag);

    res.json({
      success: true,
      images,
      pagination: {
        page: parseInt(page),
        pageSize: limit,
        total,
        pages: Math.ceil(total / limit)
      }
    });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * GET /api/images/:id - Get a specific image
 */
router.get('/images/:id', async (req, res) => {
  try {
    const image = await database.getImage(req.params.id);
    
    if (!image) {
      return res.status(404).json({ success: false, error: 'Image not found' });
    }

    image.tags = await database.getImageTags(image.id);
    
    res.json({ success: true, image });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * GET /api/images/:id/download - Download image file
 */
router.get('/images/:id/download', async (req, res) => {
  try {
    const image = await database.getImage(req.params.id);
    
    if (!image) {
      return res.status(404).json({ success: false, error: 'Image not found' });
    }

    const buffer = await storage.getImageBuffer(image.file_path);
    res.contentType(image.mime_type);
    res.send(buffer);
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * POST /api/images - Fetch and save a new image
 */
router.post('/images', async (req, res) => {
  try {
    const { source_url, tags = [] } = req.body;

    if (!source_url) {
      return res.status(400).json({ success: false, error: 'source_url is required' });
    }

    const result = await imageFetcher.fetchImage(source_url, tags);
    
    if (!result.success) {
      return res.status(400).json({ success: false, error: result.error });
    }

    const image = await database.getImage(result.imageId);
    image.tags = await database.getImageTags(image.id);

    res.status(201).json({ success: true, image });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * POST /api/images/:id/tags - Add tags to an image
 */
router.post('/images/:id/tags', async (req, res) => {
  try {
    const { tags = [] } = req.body;

    if (!Array.isArray(tags) || tags.length === 0) {
      return res.status(400).json({ success: false, error: 'tags must be a non-empty array' });
    }

    const image = await database.getImage(req.params.id);
    if (!image) {
      return res.status(404).json({ success: false, error: 'Image not found' });
    }

    await database.addTags(image.id, tags);
    
    image.tags = await database.getImageTags(image.id);

    res.json({ success: true, image });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * DELETE /api/images/:id - Delete an image
 */
router.delete('/images/:id', async (req, res) => {
  try {
    const image = await database.getImage(req.params.id);
    
    if (!image) {
      return res.status(404).json({ success: false, error: 'Image not found' });
    }

    // Delete file
    await storage.deleteImageFile(image.file_path);

    // Delete database record
    await database.deleteImage(image.id);

    res.json({ success: true, message: 'Image deleted' });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * GET /api/tags - Get all available tags
 */
router.get('/tags', async (req, res) => {
  try {
    const tags = await database.getAllTags();
    res.json({ success: true, tags });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * GET /api/stats - Get storage and image statistics
 */
router.get('/stats', async (req, res) => {
  try {
    const storageStats = await storage.getStorageStats();
    const imageCount = await database.getImageCount();

    res.json({
      success: true,
      stats: {
        imageCount,
        ...storageStats
      }
    });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * POST /api/verify - Verify all images for corruption
 */
router.post('/verify', async (req, res) => {
  try {
    const result = await imageFetcher.verifyAllImages();
    res.json({ success: true, result });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * POST /api/cleanup - Clean up old images
 */
router.post('/cleanup', async (req, res) => {
  try {
    const { daysOld = 30 } = req.body;
    
    const deleted = await database.cleanupOldImages(daysOld);
    const orphaned = await storage.cleanupOrphanedFiles(database.db);

    res.json({
      success: true,
      cleanup: {
        deletedFromDb: deleted,
        orphanedFilesRemoved: orphaned.cleaned
      }
    });
  } catch (err) {
    res.status(500).json({ success: false, error: err.message });
  }
});

/**
 * GET /api/fetcher/status - Get fetcher status
 */
router.get('/fetcher/status', (req, res) => {
  const status = imageFetcher.getStatus();
  res.json({ success: true, status });
});

module.exports = router;