// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Posimai Feed API - Media Management Endpoints
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Purpose: Allow users to add/remove custom RSS feeds
// Location: Copy this to Synology NAS at /app/server.js (Feed API section)
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

const express = require('express');
const router = express.Router();
// Assume: authMiddleware, pool (PostgreSQL) are already imported

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// POST /feed/api/media/add
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

/**
 * Add a new RSS feed source
 *
 * Request body:
 * {
 *   feedUrl: string      // RSS feed URL (required)
 *   feedName: string     // Display name (optional, auto-detected from RSS)
 *   category: string     // User-defined category (optional)
 * }
 *
 * Response:
 * {
 *   success: boolean
 *   mediaSource: { id, feedUrl, feedName, ... }
 * }
 */
router.post('/media/add', authMiddleware, async (req, res) => {
    const { feedUrl, feedName, category } = req.body || {};

    // ──────────────────────────────────────────────────────────────────
    // 1. Validation
    // ──────────────────────────────────────────────────────────────────
    if (!feedUrl) {
        return res.status(400).json({
            error: 'Missing required field: feedUrl'
        });
    }

    // Validate URL format
    try {
        new URL(feedUrl);
    } catch {
        return res.status(400).json({
            error: 'Invalid URL format'
        });
    }

    try {
        // ──────────────────────────────────────────────────────────────
        // 2. Verify RSS feed (fetch and parse)
        // ──────────────────────────────────────────────────────────────
        console.log(`[Feed API] Verifying RSS feed: ${feedUrl}`);

        const rssData = await fetchAndParseRSS(feedUrl);

        if (!rssData) {
            return res.status(400).json({
                error: 'Invalid RSS feed: Unable to parse feed'
            });
        }

        const detectedName = feedName || rssData.title || new URL(feedUrl).hostname;
        const detectedIcon = rssData.icon || null;

        // ──────────────────────────────────────────────────────────────
        // 3. Save to database
        // ──────────────────────────────────────────────────────────────
        const result = await pool.query(`
            INSERT INTO media_sources (
                user_id,
                feed_url,
                feed_name,
                feed_icon,
                category,
                is_active,
                last_fetched_at,
                created_at,
                updated_at
            ) VALUES (
                $1, $2, $3, $4, $5, true, NOW(), NOW(), NOW()
            )
            ON CONFLICT (user_id, feed_url) DO UPDATE SET
                feed_name = EXCLUDED.feed_name,
                feed_icon = EXCLUDED.feed_icon,
                category = EXCLUDED.category,
                is_active = true,
                updated_at = NOW()
            RETURNING *
        `, [
            req.userId,       // $1: user_id from authMiddleware
            feedUrl,          // $2: feed_url
            detectedName,     // $3: feed_name
            detectedIcon,     // $4: feed_icon
            category || null  // $5: category
        ]);

        const mediaSource = result.rows[0];

        console.log(`[Feed API] Media source added: ${detectedName} (ID=${mediaSource.id})`);

        // ──────────────────────────────────────────────────────────────
        // 4. Success response
        // ──────────────────────────────────────────────────────────────
        return res.json({
            success: true,
            mediaSource: {
                id: mediaSource.id,
                feedUrl: mediaSource.feed_url,
                feedName: mediaSource.feed_name,
                feedIcon: mediaSource.feed_icon,
                category: mediaSource.category,
                isActive: mediaSource.is_active,
                createdAt: mediaSource.created_at
            }
        });

    } catch (error) {
        console.error('[Feed API] Failed to add media source:', error);

        return res.status(500).json({
            error: 'Failed to add RSS feed',
            message: error.message
        });
    }
});

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// GET /feed/api/media
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

/**
 * Get all media sources for authenticated user
 *
 * Response:
 * {
 *   mediaSources: [
 *     { id, feedUrl, feedName, feedIcon, category, isActive, ... }
 *   ]
 * }
 */
router.get('/media', authMiddleware, async (req, res) => {
    try {
        const { rows } = await pool.query(`
            SELECT
                id,
                feed_url,
                feed_name,
                feed_icon,
                category,
                is_active,
                last_fetched_at,
                fetch_interval_minutes,
                created_at,
                updated_at
            FROM media_sources
            WHERE user_id = $1
            ORDER BY created_at DESC
        `, [req.userId]);

        return res.json({
            mediaSources: rows.map(row => ({
                id: row.id,
                feedUrl: row.feed_url,
                feedName: row.feed_name,
                feedIcon: row.feed_icon,
                category: row.category,
                isActive: row.is_active,
                lastFetchedAt: row.last_fetched_at,
                fetchIntervalMinutes: row.fetch_interval_minutes,
                createdAt: row.created_at,
                updatedAt: row.updated_at
            }))
        });

    } catch (error) {
        console.error('[Feed API] Failed to fetch media sources:', error);

        return res.status(500).json({
            error: 'Failed to fetch media sources',
            message: error.message
        });
    }
});

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// DELETE /feed/api/media/:id
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

/**
 * Remove a media source (soft delete - set is_active=false)
 *
 * Response:
 * {
 *   success: boolean
 * }
 */
router.delete('/media/:id', authMiddleware, async (req, res) => {
    const { id } = req.params;

    try {
        const result = await pool.query(`
            UPDATE media_sources
            SET is_active = false, updated_at = NOW()
            WHERE id = $1 AND user_id = $2
            RETURNING id
        `, [id, req.userId]);

        if (result.rowCount === 0) {
            return res.status(404).json({
                error: 'Media source not found'
            });
        }

        console.log(`[Feed API] Media source deleted: ID=${id}`);

        return res.json({
            success: true
        });

    } catch (error) {
        console.error('[Feed API] Failed to delete media source:', error);

        return res.status(500).json({
            error: 'Failed to delete media source',
            message: error.message
        });
    }
});

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Helper Functions
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

/**
 * Fetch and parse RSS feed
 *
 * @param {string} feedUrl - RSS feed URL
 * @returns {Promise<{title: string, icon: string}|null>}
 */
async function fetchAndParseRSS(feedUrl) {
    try {
        const response = await fetch(feedUrl, {
            headers: {
                'User-Agent': 'Mozilla/5.0 Posimai Feed Bot'
            },
            timeout: 10000  // 10 second timeout
        });

        if (!response.ok) {
            console.error(`[RSS] HTTP error: ${response.status}`);
            return null;
        }

        const text = await response.text();

        // Simple RSS/Atom parsing (you may want to use a library like 'rss-parser')
        // For now, we'll do basic regex matching

        // Extract <title> tag
        const titleMatch = text.match(/<title>([^<]+)<\/title>/i);
        const title = titleMatch ? titleMatch[1].trim() : null;

        // Extract <link> tag for icon (not standard, but some feeds have it)
        const iconMatch = text.match(/<image>[\s\S]*?<url>([^<]+)<\/url>/i) ||
                          text.match(/<logo>([^<]+)<\/logo>/i);
        const icon = iconMatch ? iconMatch[1].trim() : null;

        // Fallback: Try to get favicon from feed homepage
        const linkMatch = text.match(/<link>([^<]+)<\/link>/i);
        if (linkMatch && !icon) {
            const siteUrl = linkMatch[1].trim();
            try {
                const domain = new URL(siteUrl).origin;
                const faviconUrl = `${domain}/favicon.ico`;
                // Note: You might want to verify this URL exists
                return { title, icon: faviconUrl };
            } catch { }
        }

        return { title, icon };

    } catch (error) {
        console.error('[RSS] Failed to fetch/parse RSS:', error);
        return null;
    }
}

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Export
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

module.exports = router;

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// DEPLOYMENT CHECKLIST
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
//
// 1. [ ] Run database migration: synology-feed-media-add-migration.sql
// 2. [ ] Update server.js to include this router:
//        app.use('/feed/api', require('./routes/feed-media'));
// 3. [ ] Install RSS parser library (optional, for better parsing):
//        npm install rss-parser
// 4. [ ] Restart Feed API server: docker restart posimai-feed-api
// 5. [ ] Test POST /media/add with sample RSS URL
// 6. [ ] Check logs: docker logs -f posimai-feed-api
// 7. [ ] Update Feed UI to call these endpoints
//
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━