const router = require('express').Router();
const { query } = require('../db');

const STATUSES = ['pending', 'generating', 'done', 'failed'];

// GET /api/picture-jobs
router.get('/', async (req, res, next) => {
  try {
    const { status, limit = 50, offset = 0 } = req.query;
    const params = [Math.min(parseInt(limit), 500), parseInt(offset)];
    const conditions = [];
    if (status) { conditions.push(`pj.status = $${params.length + 1}`); params.push(status); }
    const where = conditions.length ? `WHERE ${conditions.join(' AND ')}` : '';
    const result = await query(
      `SELECT pj.*,
         COALESCE(json_agg(DISTINCT pjw.word_id) FILTER (WHERE pjw.word_id IS NOT NULL), '[]') AS word_ids
       FROM picture_jobs pj
       LEFT JOIN picture_job_words pjw ON pjw.picture_job_id = pj.id
       ${where}
       GROUP BY pj.id
       ORDER BY pj.created_at DESC
       LIMIT $1 OFFSET $2`,
      params
    );
    res.json(result.rows);
  } catch (err) { next(err); }
});

// GET /api/picture-jobs/:id
router.get('/:id', async (req, res, next) => {
  try {
    const result = await query(
      `SELECT pj.*,
         COALESCE(json_agg(DISTINCT pjw.word_id) FILTER (WHERE pjw.word_id IS NOT NULL), '[]') AS word_ids
       FROM picture_jobs pj
       LEFT JOIN picture_job_words pjw ON pjw.picture_job_id = pj.id
       WHERE pj.id = $1
       GROUP BY pj.id`,
      [req.params.id]
    );
    if (!result.rows.length) return res.status(404).json({ error: 'Not found' });
    res.json(result.rows[0]);
  } catch (err) { next(err); }
});

// GET /api/picture-jobs/:id/words
router.get('/:id/words', async (req, res, next) => {
  try {
    const result = await query(
      `SELECT w.* FROM words w
       JOIN picture_job_words pjw ON pjw.word_id = w.id
       WHERE pjw.picture_job_id = $1`,
      [req.params.id]
    );
    res.json(result.rows);
  } catch (err) { next(err); }
});

// POST /api/picture-jobs
router.post('/', async (req, res, next) => {
  try {
    const { kategorie_id, prompt_fix, prompt_atmosphere, prompt_setting, prompt_final, word_ids } = req.body;
    const result = await query(
      `INSERT INTO picture_jobs (kategorie_id, prompt_fix, prompt_atmosphere, prompt_setting, prompt_final)
       VALUES ($1, $2, $3, $4, $5) RETURNING *`,
      [kategorie_id || null, prompt_fix || null, prompt_atmosphere || null, prompt_setting || null, prompt_final || null]
    );
    const job = result.rows[0];
    if (Array.isArray(word_ids) && word_ids.length) {
      for (const wid of word_ids) {
        await query(
          `INSERT INTO picture_job_words (picture_job_id, word_id) VALUES ($1, $2) ON CONFLICT DO NOTHING`,
          [job.id, wid]
        ).catch(() => {});
      }
    }
    res.status(201).json({ ...job, word_ids: word_ids || [] });
  } catch (err) { next(err); }
});

// PATCH /api/picture-jobs/:id
router.patch('/:id', async (req, res, next) => {
  try {
    const allowed = ['kategorie_id', 'prompt_fix', 'prompt_atmosphere', 'prompt_setting', 'prompt_final', 'status', 'picture_id'];
    const fields = Object.keys(req.body).filter(k => allowed.includes(k));
    if (!fields.length) return res.status(400).json({ error: 'No valid fields provided' });
    if (req.body.status && !STATUSES.includes(req.body.status))
      return res.status(400).json({ error: `status must be one of: ${STATUSES.join(', ')}` });
    const setClauses = fields.map((f, i) => `${f} = $${i + 1}`).join(', ');
    const result = await query(
      `UPDATE picture_jobs SET ${setClauses} WHERE id = $${fields.length + 1} RETURNING *`,
      [...fields.map(f => req.body[f]), req.params.id]
    );
    if (!result.rows.length) return res.status(404).json({ error: 'Not found' });
    res.json(result.rows[0]);
  } catch (err) { next(err); }
});

// PUT /api/picture-jobs/:id/words/:wordId
router.put('/:id/words/:wordId', async (req, res, next) => {
  try {
    await query(
      `INSERT INTO picture_job_words (picture_job_id, word_id) VALUES ($1, $2) ON CONFLICT DO NOTHING`,
      [req.params.id, req.params.wordId]
    );
    res.status(204).end();
  } catch (err) { next(err); }
});

// DELETE /api/picture-jobs/:id/words/:wordId
router.delete('/:id/words/:wordId', async (req, res, next) => {
  try {
    await query(
      `DELETE FROM picture_job_words WHERE picture_job_id = $1 AND word_id = $2`,
      [req.params.id, req.params.wordId]
    );
    res.status(204).end();
  } catch (err) { next(err); }
});

// DELETE /api/picture-jobs/:id
router.delete('/:id', async (req, res, next) => {
  try {
    const result = await query('DELETE FROM picture_jobs WHERE id = $1 RETURNING id', [req.params.id]);
    if (!result.rows.length) return res.status(404).json({ error: 'Not found' });
    res.status(204).end();
  } catch (err) { next(err); }
});

module.exports = router;