const express = require('express');
const crypto = require('crypto');
const { requireRole } = require('../middleware/auth');

const createFunnelsRouter = ({ pool }) => {
  const router = express.Router();

  router.get('/funnels', async (req, res) => {
    try {
      const { tenantId } = req.query;
      const effectiveTenantId = req.user.role === 'super_admin' ? tenantId : req.user.tenant_id;
      if (!effectiveTenantId || effectiveTenantId === 'all') return res.json([]);

      const [funnels] = await pool.query('SELECT * FROM funnels WHERE tenant_id = ? ORDER BY created_at ASC', [effectiveTenantId]);

      if (funnels.length === 0) {
        const fid = `funnel_${crypto.randomUUID().split('-')[0]}`;
        await pool.query('INSERT INTO funnels (id, tenant_id, name) VALUES (?, ?, ?)', [fid, effectiveTenantId, 'Funil Padrão']);

        const defaultStages = [
          { name: 'Sem atendimento', color: 'bg-zinc-100 text-zinc-700 border-zinc-200 dark:bg-dark-input dark:text-dark-muted dark:border-dark-border', order: 0 },
          { name: 'Identificação', color: 'bg-blue-100 text-blue-700 border-blue-200 dark:bg-blue-900/30 dark:text-blue-400 dark:border-blue-800', order: 1 },
          { name: 'Negociação', color: 'bg-purple-100 text-purple-700 border-purple-200 dark:bg-purple-900/30 dark:text-purple-400 dark:border-purple-800', order: 2 },
          { name: 'Ganhos', color: 'bg-green-100 text-green-700 border-green-200 dark:bg-green-900/30 dark:text-green-400 dark:border-green-800', order: 3 },
          { name: 'Perdidos', color: 'bg-red-100 text-red-700 border-red-200 dark:bg-red-900/30 dark:text-red-400 dark:border-red-800', order: 4 }
        ];

        for (const s of defaultStages) {
          const sid = `stage_${crypto.randomUUID().split('-')[0]}`;
          await pool.query(
            'INSERT INTO funnel_stages (id, funnel_id, name, color_class, order_index) VALUES (?, ?, ?, ?, ?)',
            [sid, fid, s.name, s.color, s.order]
          );
        }

        await pool.query('UPDATE teams SET funnel_id = ? WHERE tenant_id = ? AND funnel_id IS NULL', [fid, effectiveTenantId]);
        funnels.push({ id: fid, tenant_id: effectiveTenantId, name: 'Funil Padrão' });
      }

      const [stages] = await pool.query('SELECT * FROM funnel_stages WHERE funnel_id IN (?) ORDER BY order_index ASC', [funnels.map(f => f.id)]);
      const [teams] = await pool.query('SELECT id, funnel_id FROM teams WHERE tenant_id = ? AND funnel_id IS NOT NULL', [effectiveTenantId]);

      const result = funnels.map(f => ({
        ...f,
        stages: stages.filter(s => s.funnel_id === f.id),
        teamIds: teams.filter(t => t.funnel_id === f.id).map(t => t.id)
      }));

      res.json(result);
    } catch (error) {
      console.error("GET /funnels error:", error);
      res.status(500).json({ error: error.message });
    }
  });

  router.post('/funnels', requireRole(['admin', 'super_admin']), async (req, res) => {
    const { name, tenantId } = req.body;
    const effectiveTenantId = req.user.role === 'super_admin' ? tenantId : req.user.tenant_id;
    try {
      const fid = `funnel_${crypto.randomUUID().split('-')[0]}`;
      await pool.query('INSERT INTO funnels (id, tenant_id, name) VALUES (?, ?, ?)', [fid, effectiveTenantId, name]);
      res.status(201).json({ id: fid });
    } catch (error) {
      res.status(500).json({ error: error.message });
    }
  });

  router.put('/funnels/:id', requireRole(['admin', 'super_admin']), async (req, res) => {
    const { name, teamIds } = req.body;
    try {
      if (name) {
        await pool.query('UPDATE funnels SET name = ? WHERE id = ?', [name, req.params.id]);
      }
      if (teamIds && Array.isArray(teamIds)) {
        await pool.query('UPDATE teams SET funnel_id = NULL WHERE funnel_id = ?', [req.params.id]);
        if (teamIds.length > 0) {
          await pool.query('UPDATE teams SET funnel_id = ? WHERE id IN (?)', [req.params.id, teamIds]);
        }
      }
      res.json({ message: 'Funnel updated.' });
    } catch (error) {
      res.status(500).json({ error: error.message });
    }
  });

  router.delete('/funnels/:id', requireRole(['admin', 'super_admin']), async (req, res) => {
    try {
      await pool.query('DELETE FROM funnel_stages WHERE funnel_id = ?', [req.params.id]);
      await pool.query('UPDATE teams SET funnel_id = NULL WHERE funnel_id = ?', [req.params.id]);
      await pool.query('DELETE FROM funnels WHERE id = ?', [req.params.id]);
      res.json({ message: 'Funnel deleted.' });
    } catch (error) {
      res.status(500).json({ error: error.message });
    }
  });

  router.post('/funnels/:id/stages', requireRole(['admin', 'super_admin']), async (req, res) => {
    const { name, color_class, order_index } = req.body;
    try {
      const sid = `stage_${crypto.randomUUID().split('-')[0]}`;
      await pool.query(
        'INSERT INTO funnel_stages (id, funnel_id, name, color_class, order_index) VALUES (?, ?, ?, ?, ?)',
        [sid, req.params.id, name, color_class, order_index || 0]
      );
      res.status(201).json({ id: sid });
    } catch (error) {
      res.status(500).json({ error: error.message });
    }
  });

  router.put('/funnel_stages/:id', requireRole(['admin', 'super_admin']), async (req, res) => {
    const { name, color_class, order_index } = req.body;
    try {
      const [existing] = await pool.query('SELECT * FROM funnel_stages WHERE id = ?', [req.params.id]);
      if (existing.length === 0) return res.status(404).json({ error: 'Stage not found' });

      await pool.query(
        'UPDATE funnel_stages SET name = ?, color_class = ?, order_index = ? WHERE id = ?',
        [name || existing[0].name, color_class || existing[0].color_class, order_index !== undefined ? order_index : existing[0].order_index, req.params.id]
      );
      res.json({ message: 'Stage updated.' });
    } catch (error) {
      res.status(500).json({ error: error.message });
    }
  });

  router.delete('/funnel_stages/:id', requireRole(['admin', 'super_admin']), async (req, res) => {
    try {
      await pool.query('DELETE FROM funnel_stages WHERE id = ?', [req.params.id]);
      res.json({ message: 'Stage deleted.' });
    } catch (error) {
      res.status(500).json({ error: error.message });
    }
  });

  return router;
};

module.exports = {
  createFunnelsRouter,
};