const express = require('express');
const multer = require('multer');
const { authRequired } = require('../middleware/auth');
const { requireRole } = require('../middleware/rbac');
const { resolveTenant } = require('../middleware/tenant');
const { createSurveyPeriod, activateSurvey, closeSurvey } = require('../services/surveyService');
const { importUsersFromExcel } = require('../services/importService');
const { getParticipationSummary } = require('../services/participationService');
const {
  listQuestions,
  exportQuestionsExcel,
  exportQuestionsTemplate,
  importQuestionsExcel,
  listQuestionSets,
  listDimensions,
  createDimension,
  createQuestionSetFromCurrent,
  createQuestionSetEmpty,
  addQuestionToSet
} = require('../services/questionService');
const {
  listResultModel,
  createResultModel,
  updateResultModel,
  exportResultModelTemplate,
  importResultModelExcel
} = require('../services/resultModelService');

const upload = multer();
const router = express.Router();

router.use(authRequired, requireRole('admin', 'superadmin'), resolveTenant);

router.get('/survey-periods', async (req, res, next) => {
  try {
    const [rows] = await req.tenantPool.query('SELECT * FROM survey_periods ORDER BY id DESC');
    res.json(rows);
  } catch (err) {
    next(err);
  }
});

router.post('/survey-periods', async (req, res, next) => {
  try {
    const { year, month, fecha_inicio, fecha_fin } = req.body;
    if (!year || !month || !fecha_inicio || !fecha_fin) return res.status(400).json({ error: 'Campos requeridos' });
    const period = await createSurveyPeriod(req.tenantPool, { year, month, fecha_inicio, fecha_fin });
    res.json(period);
  } catch (err) {
    next(err);
  }
});

router.patch('/survey-periods/:id/activate', async (req, res, next) => {
  try {
    await activateSurvey(req.tenantPool, req.params.id);
    res.json({ ok: true });
  } catch (err) {
    next(err);
  }
});

router.patch('/survey-periods/:id/close', async (req, res, next) => {
  try {
    const result = await closeSurvey(req.tenantPool, req.params.id);
    res.json({ ok: true, result });
  } catch (err) {
    next(err);
  }
});

router.get('/dashboard', async (req, res, next) => {
  try {
    const [[current]] = await req.tenantPool.query(
      'SELECT score, classification, participation_rate FROM survey_results WHERE scope = "global" ORDER BY survey_period_id DESC LIMIT 1'
    );
    const [dimensions] = await req.tenantPool.query(
      'SELECT d.name, r.score, r.classification FROM survey_results r JOIN dimensions d ON d.id = r.dimension_id WHERE r.scope = "dimension" AND r.survey_period_id = (SELECT MAX(id) FROM survey_periods WHERE estado = "cerrada")'
    );
    const [history] = await req.tenantPool.query(
      'SELECT sp.codigo_medicion, r.score FROM survey_results r JOIN survey_periods sp ON sp.id = r.survey_period_id WHERE r.scope = "global" ORDER BY sp.id DESC'
    );
    const participation = await getParticipationSummary(req.tenantPool);
    res.json({ current, dimensions, history, participation });
  } catch (err) {
    next(err);
  }
});

router.post('/users/import', upload.single('file'), async (req, res, next) => {
  try {
    if (!req.file) return res.status(400).json({ error: 'Archivo requerido' });
    const result = await importUsersFromExcel(req.file.buffer, req.tenantPool);
    res.json(result);
  } catch (err) {
    next(err);
  }
});

router.get('/questions', async (req, res, next) => {
  try {
    const rows = await listQuestions(req.tenantPool);
    res.json(rows);
  } catch (err) {
    next(err);
  }
});

router.get('/questions/export', async (req, res, next) => {
  try {
    const buffer = await exportQuestionsExcel(req.tenantPool);
    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
    res.setHeader('Content-Disposition', 'attachment; filename=\"preguntas.xlsx\"');
    res.send(buffer);
  } catch (err) {
    next(err);
  }
});

router.get('/questions/template', async (req, res, next) => {
  try {
    const buffer = await exportQuestionsTemplate();
    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
    res.setHeader('Content-Disposition', 'attachment; filename=\"preguntas_template.xlsx\"');
    res.send(buffer);
  } catch (err) {
    next(err);
  }
});

router.post('/questions/import', upload.single('file'), async (req, res, next) => {
  try {
    if (!req.file) return res.status(400).json({ error: 'Archivo requerido' });
    const setId = req.body?.set_id ? Number(req.body.set_id) : null;
    const result = await importQuestionsExcel(req.file.buffer, req.tenantPool, setId);
    res.json(result);
  } catch (err) {
    next(err);
  }
});

router.get('/question-sets', async (req, res, next) => {
  try {
    const rows = await listQuestionSets(req.tenantPool);
    res.json(rows);
  } catch (err) {
    next(err);
  }
});

router.post('/question-sets', async (req, res, next) => {
  try {
    const { name, empty } = req.body;
    const result = empty ? await createQuestionSetEmpty(req.tenantPool, name) : await createQuestionSetFromCurrent(req.tenantPool, name);
    res.json(result);
  } catch (err) {
    next(err);
  }
});

router.delete('/question-sets/:id', async (req, res, next) => {
  try {
    const [rows] = await req.tenantPool.query('SELECT id, code, is_active FROM question_sets WHERE id = ?', [req.params.id]);
    if (!rows.length) return res.status(404).json({ error: 'Set no encontrado' });
    const setRow = rows[0];
    if (setRow.is_active) {
      return res.status(400).json({ error: 'No se puede eliminar un set activo' });
    }
    const [[{ used }]] = await req.tenantPool.query('SELECT COUNT(*) AS used FROM survey_periods WHERE question_set_code = ?', [setRow.code]);
    if (used > 0) {
      return res.status(400).json({ error: 'No se puede eliminar: ya tiene mediciones' });
    }
    await req.tenantPool.query('DELETE FROM question_set_questions WHERE question_set_id = ?', [setRow.id]);
    await req.tenantPool.query('DELETE FROM question_sets WHERE id = ?', [setRow.id]);
    res.json({ ok: true });
  } catch (err) {
    next(err);
  }
});

router.get('/question-sets/:id/questions', async (req, res, next) => {
  try {
    const [rows] = await req.tenantPool.query(
      'SELECT qs.question_code, qs.text_snapshot, d.name AS dimension FROM question_set_questions qs JOIN dimensions d ON d.id = qs.dimension_id WHERE qs.question_set_id = ? ORDER BY qs.sort_order',
      [req.params.id]
    );
    res.json(rows);
  } catch (err) {
    next(err);
  }
});

router.get('/result-model', async (req, res, next) => {
  try {
    const rows = await listResultModel(req.tenantPool);
    res.json(rows);
  } catch (err) {
    next(err);
  }
});

router.post('/result-model', async (req, res, next) => {
  try {
    const { dimension, variable, subvariable, score_value, max_score, sort_order } = req.body;
    if (!dimension || !variable || !subvariable) {
      return res.status(400).json({ error: 'dimension, variable y subvariable requeridos' });
    }
    const result = await createResultModel(req.tenantPool, { dimension, variable, subvariable, score_value, max_score, sort_order });
    res.json(result);
  } catch (err) {
    next(err);
  }
});

router.patch('/result-model/:id', async (req, res, next) => {
  try {
    const { score_value, max_score, sort_order } = req.body;
    await updateResultModel(req.tenantPool, req.params.id, { score_value, max_score, sort_order });
    res.json({ ok: true });
  } catch (err) {
    next(err);
  }
});

router.get('/result-model/template', async (req, res, next) => {
  try {
    const buffer = await exportResultModelTemplate();
    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
    res.setHeader('Content-Disposition', 'attachment; filename=\"clima_result_model.xlsx\"');
    res.send(buffer);
  } catch (err) {
    next(err);
  }
});

router.post('/result-model/import', upload.single('file'), async (req, res, next) => {
  try {
    if (!req.file) return res.status(400).json({ error: 'Archivo requerido' });
    const mode = req.body?.mode || 'replace';
    const result = await importResultModelExcel(req.file.buffer, req.tenantPool, mode);
    res.json(result);
  } catch (err) {
    next(err);
  }
});

router.get('/dimensions', async (req, res, next) => {
  try {
    const rows = await listDimensions(req.tenantPool);
    res.json(rows);
  } catch (err) {
    next(err);
  }
});

router.post('/dimensions', async (req, res, next) => {
  try {
    const { name, code, description } = req.body;
    if (!name) return res.status(400).json({ error: 'Nombre requerido' });
    const result = await createDimension(req.tenantPool, { name, code, description });
    res.json(result);
  } catch (err) {
    next(err);
  }
});

router.post('/question-sets/:id/questions', async (req, res, next) => {
  try {
    const { dimension_id, text } = req.body;
    if (!dimension_id || !text) return res.status(400).json({ error: 'dimension_id y text requeridos' });
    const result = await addQuestionToSet(req.tenantPool, { questionSetId: req.params.id, dimensionId: dimension_id, text });
    res.json(result);
  } catch (err) {
    next(err);
  }
});

module.exports = router;