const express = require('express');
const { body, param, query } = require('express-validator');
const { pool } = require('../models/db');
const { authenticate, requireRole } = require('../middleware/auth');
const validate = require('../middleware/validate');
const Notifications = require('../models/notifications');
const { sendNotificationEmail } = require('../utils/email');

const router = express.Router();

// Submit a bug report (authenticated users)
router.post('/',
  authenticate,
  validate([
    body('title').trim().isLength({ min: 5, max: 200 }).withMessage('Title must be 5-200 characters'),
    body('description').trim().isLength({ min: 10, max: 5000 }).withMessage('Description must be 10-5000 characters'),
    body('pageUrl').optional().trim().isLength({ max: 500 })
  ]),
  async (req, res, next) => {
    try {
      const { title, description, pageUrl } = req.body;

      const result = await pool.query(
        `INSERT INTO bug_reports (user_id, title, description, page_url)
         VALUES ($1, $2, $3, $4)
         RETURNING *`,
        [req.user.id, title, description, pageUrl || null]
      );

      res.status(201).json({
        message: 'Bug report submitted. Thank you for helping improve GamerComp!',
        report: result.rows[0]
      });
    } catch (error) {
      next(error);
    }
  }
);

// Get my bug reports (authenticated users)
router.get('/my-reports',
  authenticate,
  async (req, res, next) => {
    try {
      const result = await pool.query(
        `SELECT id, title, status, priority, created_at, resolved_at
         FROM bug_reports
         WHERE user_id = $1
         ORDER BY created_at DESC`,
        [req.user.id]
      );

      res.json({ reports: result.rows });
    } catch (error) {
      next(error);
    }
  }
);

// Admin: Get all bug reports
router.get('/admin',
  authenticate,
  requireRole('admin'),
  async (req, res, next) => {
    try {
      const { status, priority } = req.query;

      let query = `
        SELECT br.*,
               u.username as reporter_username,
               u.email as reporter_email,
               resolver.username as resolver_username
        FROM bug_reports br
        LEFT JOIN users u ON br.user_id = u.id
        LEFT JOIN users resolver ON br.resolved_by = resolver.id
        WHERE 1=1
      `;
      const params = [];

      if (status && status !== 'all') {
        params.push(status);
        query += ` AND br.status = $${params.length}`;
      }

      if (priority && priority !== 'all') {
        params.push(priority);
        query += ` AND br.priority = $${params.length}`;
      }

      query += ` ORDER BY
        CASE br.priority
          WHEN 'critical' THEN 1
          WHEN 'high' THEN 2
          WHEN 'normal' THEN 3
          WHEN 'low' THEN 4
        END,
        br.created_at DESC`;

      const result = await pool.query(query, params);

      // Get counts by status
      const countsResult = await pool.query(`
        SELECT status, COUNT(*) as count
        FROM bug_reports
        GROUP BY status
      `);
      const counts = {};
      countsResult.rows.forEach(row => {
        counts[row.status] = parseInt(row.count);
      });

      res.json({
        reports: result.rows,
        counts
      });
    } catch (error) {
      next(error);
    }
  }
);

// Admin: Update bug report status
router.put('/admin/:id',
  authenticate,
  requireRole('admin'),
  validate([
    param('id').isInt(),
    body('status').isIn(['open', 'in_progress', 'resolved', 'closed', 'wont_fix']),
    body('priority').optional().isIn(['low', 'normal', 'high', 'critical']),
    body('adminNotes').optional().trim().isLength({ max: 2000 })
  ]),
  async (req, res, next) => {
    try {
      const { id } = req.params;
      const { status, priority, adminNotes } = req.body;

      // Get the current bug report
      const current = await pool.query(
        'SELECT * FROM bug_reports WHERE id = $1',
        [id]
      );

      if (current.rows.length === 0) {
        return res.status(404).json({ error: 'Bug report not found' });
      }

      const bug = current.rows[0];
      const wasResolved = ['resolved', 'closed'].includes(bug.status);
      const isNowResolved = ['resolved', 'closed'].includes(status);

      // Update the bug report
      const isResolvingNow = ['resolved', 'closed'].includes(status);
      const result = await pool.query(
        `UPDATE bug_reports
         SET status = $2,
             priority = COALESCE($3, priority),
             admin_notes = COALESCE($4, admin_notes),
             resolved_at = CASE WHEN $5 AND resolved_at IS NULL THEN NOW() ELSE resolved_at END,
             resolved_by = CASE WHEN $5 AND resolved_by IS NULL THEN $6 ELSE resolved_by END,
             updated_at = NOW()
         WHERE id = $1
         RETURNING *`,
        [id, status, priority || null, adminNotes || null, isResolvingNow, req.user.id]
      );

      // If status changed to resolved/closed and user exists, notify them
      if (!wasResolved && isNowResolved && bug.user_id) {
        const statusText = status === 'resolved' ? 'has been fixed' : 'has been closed';
        const notifMessage = `Your bug report "${bug.title}" ${statusText}. Thank you for helping improve GamerComp!`;
        await Notifications.create({
          userId: bug.user_id,
          type: 'bug_resolved',
          title: 'Bug Report Updated',
          message: notifMessage,
          link: null
        });

        // Send email notification
        const userResult = await pool.query('SELECT email FROM users WHERE id = $1', [bug.user_id]);
        if (userResult.rows.length > 0 && userResult.rows[0].email) {
          sendNotificationEmail(
            { email: userResult.rows[0].email },
            { title: 'Bug Report Updated', message: notifMessage }
          ).catch(() => {});
        }
      }

      res.json({
        message: 'Bug report updated',
        report: result.rows[0]
      });
    } catch (error) {
      next(error);
    }
  }
);

// Admin: Delete bug report
router.delete('/admin/:id',
  authenticate,
  requireRole('admin'),
  validate([param('id').isInt()]),
  async (req, res, next) => {
    try {
      const { id } = req.params;

      await pool.query('DELETE FROM bug_reports WHERE id = $1', [id]);

      res.json({ message: 'Bug report deleted' });
    } catch (error) {
      next(error);
    }
  }
);

module.exports = router;