import express from 'express';
import pool from '../db/pool.js';
import { validateUuid } from '../middleware/errors.js';
import { v4 as uuidv4 } from 'uuid';

const router = express.Router();
router.param('id', (req, res, next) => validateUuid('id')(req, res, next));

// Helper function to slugify
const slugify = (str) => {
  return str
    .toLowerCase()
    .trim()
    .replace(/[^\w\s-]/g, '')
    .replace(/\s+/g, '-')
    .replace(/-+/g, '-');
};

// GET / - List all projects
router.get('/', async (req, res, next) => {
  try {
    const result = await pool.query('SELECT * FROM projects ORDER BY created_at DESC');
    res.json(result.rows);
  } catch (err) {
    next(err);
  }
});

// POST / - Create project
router.post('/', async (req, res, next) => {
  try {
    const { name, description } = req.body;

    if (!name) {
      return res.status(400).json({ error: 'Name is required' });
    }

    const id = uuidv4();
    const s3_prefix = slugify(name);

    const result = await pool.query(
      `INSERT INTO projects (id, name, description, s3_prefix, created_at, updated_at)
       VALUES ($1, $2, $3, $4, NOW(), NOW())
       RETURNING *`,
      [id, name, description || null, s3_prefix]
    );

    res.status(201).json(result.rows[0]);
  } catch (err) {
    next(err);
  }
});

// GET /:id - Single project with asset count
router.get('/:id', async (req, res, next) => {
  try {
    const { id } = req.params;

    const result = await pool.query(
      `SELECT p.*,
              COUNT(a.id) AS asset_count
       FROM projects p
       LEFT JOIN assets a ON a.project_id = p.id AND a.status != 'archived'
       WHERE p.id = $1
       GROUP BY p.id`,
      [id]
    );

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

    res.json(result.rows[0]);
  } catch (err) {
    next(err);
  }
});

// PATCH /:id - Update project
router.patch('/:id', async (req, res, next) => {
  try {
    const { id } = req.params;
    const { name, description } = req.body;

    const updates = [];
    const params = [];
    let paramCount = 1;

    if (name !== undefined) {
      updates.push(`name = $${paramCount++}`);
      params.push(name);
    }

    if (description !== undefined) {
      updates.push(`description = $${paramCount++}`);
      params.push(description);
    }

    if (updates.length === 0) {
      return res.status(400).json({ error: 'No fields to update' });
    }

    updates.push(`updated_at = NOW()`);
    params.push(id);

    const query = `
      UPDATE projects
      SET ${updates.join(', ')}
      WHERE id = $${paramCount}
      RETURNING *
    `;

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

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

    res.json(result.rows[0]);
  } catch (err) {
    next(err);
  }
});

// DELETE /:id - Delete project and cascade
router.delete('/:id', async (req, res, next) => {
  try {
    const { id } = req.params;

    // Delete project (cascade should handle related records)
    const result = await pool.query(
      'DELETE FROM projects WHERE id = $1 RETURNING *',
      [id]
    );

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

    res.json({ message: 'Project deleted', project: result.rows[0] });
  } catch (err) {
    next(err);
  }
});

export default router;