/**
 * Rutas para gestión de recursos multimedia
 */

import express, { Response } from 'express';
import { authenticate, requirePermission, AuthRequest } from '../middleware/auth.js';
import { query } from '../../config/database.js';
import multer from 'multer';
import { join } from 'path';
import { mkdir, writeFile, unlink, stat, readFile } from 'fs/promises';
import { createHash } from 'crypto';

const router = express.Router();

router.use(authenticate);

// Configurar multer para upload
const storageDir = process.env.MEDIA_STORAGE_DIR || join(process.cwd(), 'storage', 'media');
const upload = multer({
  dest: storageDir,
  limits: {
    fileSize: 50 * 1024 * 1024, // 50MB
  },
  fileFilter: (_req, file, cb) => {
    // Permitir imágenes y vídeos
    const allowedMimes = [
      'image/jpeg', 'image/png', 'image/gif', 'image/webp', 'image/svg+xml',
      'video/mp4', 'video/webm', 'video/ogg',
    ];
    if (allowedMimes.includes(file.mimetype)) {
      cb(null, true);
    } else {
      cb(new Error('Tipo de archivo no permitido') as any, false);
    }
  },
});

// Asegurar que existe el directorio
mkdir(storageDir, { recursive: true }).catch(console.error);

/**
 * POST /api/media/upload
 * Subir un recurso multimedia
 */
router.post('/upload', requirePermission('content:write'), upload.single('file'), async (req: AuthRequest, res: Response) => {
  try {
    if (!req.file) {
      res.status(400).json({ error: 'No se proporcionó archivo' });
      return;
    }

    const { title, description, alt_text, tags, block, chapter, priority } = req.body;
    const file = req.file;

    // Determinar tipo
    const type = file.mimetype.startsWith('image/') ? 'image' : 'video';

    // Generar nombre único
    const ext = file.originalname.split('.').pop();
    const hash = createHash('md5').update(file.path + Date.now()).digest('hex').substring(0, 8);
    const filename = `${hash}.${ext}`;
    const finalPath = join(storageDir, filename);

    // Mover archivo a nombre final
    await writeFile(finalPath, await readFile(file.path));
    await unlink(file.path);

    // URL pública
    const fileUrl = `/storage/media/${filename}`;

    // Obtener metadata del archivo
    const stats = await stat(finalPath);
    // width, height, duration se pueden obtener con sharp o similar en el futuro

    // Insertar en BD
    const result = await query(`
      INSERT INTO tes_content.media_resources (
        type, path, filename, file_url, title, description, alt_text,
        tags, block, chapter, priority, file_size, format, status
      ) VALUES (
        $1::tes_content.media_type,
        $2,
        $3,
        $4,
        $5,
        $6,
        $7,
        $8::text[],
        $9,
        $10,
        $11::tes_content.priority,
        $12,
        $13,
        'published'::tes_content.content_status
      )
      RETURNING id, type, file_url, title, created_at
    `, [
      type,
      finalPath,
      filename,
      fileUrl,
      title || file.originalname,
      description || null,
      alt_text || null,
      tags ? (Array.isArray(tags) ? tags : String(tags).split(',').map((t: string) => t.trim())) : [],
      block || null,
      chapter || null,
      priority || 'media',
      stats.size,
      ext,
    ]);

    res.json({
      success: true,
      resource: result.rows[0],
    });
  } catch (error) {
    console.error('Error subiendo recurso:', error);
    const errorMessage = error instanceof Error ? error.message : 'Error desconocido';
    res.status(500).json({ 
      error: 'Error subiendo recurso',
      message: errorMessage 
    });
  }
});

/**
 * GET /api/media
 * Listar recursos multimedia
 */
router.get('/', requirePermission('content:read'), async (req: AuthRequest, res: Response) => {
  try {
    const { type, search, page = '1', pageSize = '20' } = req.query;
    
    const pageNum = typeof page === 'string' ? parseInt(page) : 1;
    const pageSizeNum = typeof pageSize === 'string' ? parseInt(pageSize) : 20;
    
    let whereConditions: string[] = [];
    let params: any[] = [];
    let paramIndex = 1;

    if (type) {
      whereConditions.push(`type = $${paramIndex++}`);
      params.push(type);
    }

    if (search) {
      whereConditions.push(`(title ILIKE $${paramIndex} OR description ILIKE $${paramIndex} OR alt_text ILIKE $${paramIndex})`);
      params.push(`%${search}%`);
      paramIndex++;
    }

    const whereClause = whereConditions.length > 0 
      ? `WHERE ${whereConditions.join(' AND ')}`
      : '';

    // Contar total
    const countResult = await query(
      `SELECT COUNT(*) as total FROM tes_content.media_resources ${whereClause}`,
      params
    );
    const total = parseInt(countResult.rows[0].total);

    // Obtener items
    const offset = (pageNum - 1) * pageSizeNum;
    params.push(pageSizeNum, offset);
    const itemsResult = await query(
      `SELECT id, type, file_url, title, description, alt_text, tags, 
              priority, status, file_size, format, created_at, updated_at
       FROM tes_content.media_resources 
       ${whereClause}
       ORDER BY created_at DESC
       LIMIT $${paramIndex} OFFSET $${paramIndex + 1}`,
      params
    );

    res.json({
      items: itemsResult.rows,
      total,
      page: pageNum,
      pageSize: pageSizeNum,
    });
  } catch (error) {
    console.error('Error listando recursos:', error);
    res.status(500).json({ error: 'Error interno del servidor' });
  }
});

/**
 * GET /api/media/:id
 * Obtener un recurso específico
 */
router.get('/:id', requirePermission('content:read'), async (req: AuthRequest, res: Response) => {
  try {
    const { id } = req.params;
    const result = await query(
      `SELECT * FROM tes_content.media_resources WHERE id = $1`,
      [id]
    );

    if (result.rows.length === 0) {
      res.status(404).json({ error: 'Recurso no encontrado' });
      return;
    }

    res.json(result.rows[0]);
    return;
  } catch (error) {
    console.error('Error obteniendo recurso:', error);
    res.status(500).json({ error: 'Error interno del servidor' });
  }
});

/**
 * DELETE /api/media/:id
 * Eliminar un recurso
 */
router.delete('/:id', requirePermission('content:write'), async (req: AuthRequest, res: Response) => {
  try {
    const { id } = req.params;

    // Obtener información del archivo
    const result = await query(
      `SELECT path FROM tes_content.media_resources WHERE id = $1`,
      [id]
    );

    if (result.rows.length === 0) {
      res.status(404).json({ error: 'Recurso no encontrado' });
      return;
    }

    // Eliminar archivo físico
    try {
      await unlink(result.rows[0].path);
    } catch (error) {
      console.warn('No se pudo eliminar archivo físico:', error);
    }

    // Eliminar de BD
    await query(
      `DELETE FROM tes_content.media_resources WHERE id = $1`,
      [id]
    );

    res.json({ success: true });
    return;
  } catch (error) {
    console.error('Error eliminando recurso:', error);
    res.status(500).json({ error: 'Error interno del servidor' });
  }
});

/**
 * GET /api/media/orphaned
 * Obtener recursos huérfanos (sin asociaciones)
 */
router.get('/orphaned/list', requirePermission('content:read'), async (_req: AuthRequest, res: Response) => {
  try {
    const result = await query(`
      SELECT mr.*
      FROM tes_content.media_resources mr
      LEFT JOIN tes_content.content_resource_associations cra ON mr.id = cra.media_resource_id
      WHERE cra.id IS NULL
        AND mr.status = 'published'
      ORDER BY mr.created_at DESC
    `);

    res.json({ items: result.rows, total: result.rows.length });
  } catch (error) {
    console.error('Error obteniendo recursos huérfanos:', error);
    res.status(500).json({ error: 'Error interno del servidor' });
  }
});

export default router;