const express = require('express');
const router = express.Router();
const pool = require('../db');

// GET /api/dashboard/stats — Dashboard statistics
router.get('/stats', async (req, res) => {
  try {
    // All queries in parallel for speed
    const [
      byState,
      byPriority,
      byQueue,
      todayCount,
      weekCount,
      totalOpen,
      recentTickets,
      escalated,
    ] = await Promise.all([
      // Tickets by state (only open-ish states)
      pool.query(
        `SELECT ts.name AS state, tst.name AS state_type, COUNT(*) AS count
         FROM ticket t
         JOIN ticket_state ts ON t.ticket_state_id = ts.id
         JOIN ticket_state_type tst ON ts.type_id = tst.id
         WHERE tst.name IN ('new', 'open', 'pending reminder', 'pending auto')
         GROUP BY ts.name, tst.name
         ORDER BY count DESC`
      ),
      // Tickets by priority (open only)
      pool.query(
        `SELECT tp.name AS priority, tp.color, COUNT(*) AS count
         FROM ticket t
         JOIN ticket_priority tp ON t.ticket_priority_id = tp.id
         JOIN ticket_state ts ON t.ticket_state_id = ts.id
         JOIN ticket_state_type tst ON ts.type_id = tst.id
         WHERE tst.name IN ('new', 'open', 'pending reminder', 'pending auto')
         GROUP BY tp.name, tp.color, tp.id
         ORDER BY tp.id`
      ),
      // Tickets by queue (open only, top 10)
      pool.query(
        `SELECT q.name AS queue, COUNT(*) AS count
         FROM ticket t
         JOIN queue q ON t.queue_id = q.id
         JOIN ticket_state ts ON t.ticket_state_id = ts.id
         JOIN ticket_state_type tst ON ts.type_id = tst.id
         WHERE tst.name IN ('new', 'open', 'pending reminder', 'pending auto')
         GROUP BY q.name
         ORDER BY count DESC
         LIMIT 10`
      ),
      // Created today
      pool.query(
        `SELECT COUNT(*) AS count FROM ticket
         WHERE create_time >= CURRENT_DATE`
      ),
      // Created this week
      pool.query(
        `SELECT COUNT(*) AS count FROM ticket
         WHERE create_time >= date_trunc('week', CURRENT_DATE)`
      ),
      // Total open
      pool.query(
        `SELECT COUNT(*) AS count
         FROM ticket t
         JOIN ticket_state ts ON t.ticket_state_id = ts.id
         JOIN ticket_state_type tst ON ts.type_id = tst.id
         WHERE tst.name IN ('new', 'open', 'pending reminder', 'pending auto')`
      ),
      // 10 most recent tickets
      pool.query(
        `SELECT t.id, t.tn, t.title, ts.name AS state_name,
                tp.name AS priority_name, tp.color AS priority_color,
                q.name AS queue_name, t.create_time
         FROM ticket t
         JOIN ticket_state ts ON t.ticket_state_id = ts.id
         JOIN ticket_priority tp ON t.ticket_priority_id = tp.id
         JOIN queue q ON t.queue_id = q.id
         ORDER BY t.create_time DESC
         LIMIT 10`
      ),
      // Escalated tickets
      pool.query(
        `SELECT COUNT(*) AS count FROM ticket
         WHERE escalation_time > 0
           AND escalation_time < EXTRACT(EPOCH FROM NOW())`
      ),
    ]);

    res.json({
      by_state: byState.rows,
      by_priority: byPriority.rows,
      by_queue: byQueue.rows,
      created_today: parseInt(todayCount.rows[0].count),
      created_this_week: parseInt(weekCount.rows[0].count),
      total_open: parseInt(totalOpen.rows[0].count),
      recent_tickets: recentTickets.rows,
      escalated: parseInt(escalated.rows[0].count),
    });
  } catch (err) {
    console.error('Error fetching dashboard stats:', err);
    res.status(500).json({ error: err.message });
  }
});

module.exports = router;