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

// GET all heat cycles for a dog
router.get('/heat-cycles/dog/:dogId', (req, res) => {
  try {
    const db = getDatabase();
    const cycles = db.prepare(`
      SELECT * FROM heat_cycles 
      WHERE dog_id = ? 
      ORDER BY start_date DESC
    `).all(req.params.dogId);
    
    res.json(cycles);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// GET all active heat cycles
router.get('/heat-cycles/active', (req, res) => {
  try {
    const db = getDatabase();
    const cycles = db.prepare(`
      SELECT hc.*, d.name as dog_name, d.registration_number
      FROM heat_cycles hc
      JOIN dogs d ON hc.dog_id = d.id
      WHERE hc.end_date IS NULL OR hc.end_date >= date('now', '-30 days')
      ORDER BY hc.start_date DESC
    `).all();
    
    res.json(cycles);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// POST create heat cycle
router.post('/heat-cycles', (req, res) => {
  try {
    const { dog_id, start_date, end_date, progesterone_peak_date, breeding_date, breeding_successful, notes } = req.body;
    
    if (!dog_id || !start_date) {
      return res.status(400).json({ error: 'Dog ID and start date are required' });
    }
    
    const db = getDatabase();
    
    // Verify dog is female
    const dog = db.prepare('SELECT sex FROM dogs WHERE id = ?').get(dog_id);
    if (!dog || dog.sex !== 'female') {
      return res.status(400).json({ error: 'Dog must be female' });
    }
    
    const result = db.prepare(`
      INSERT INTO heat_cycles (dog_id, start_date, end_date, progesterone_peak_date, breeding_date, breeding_successful, notes)
      VALUES (?, ?, ?, ?, ?, ?, ?)
    `).run(dog_id, start_date, end_date, progesterone_peak_date, breeding_date, breeding_successful || 0, notes);
    
    const cycle = db.prepare('SELECT * FROM heat_cycles WHERE id = ?').get(result.lastInsertRowid);
    
    res.status(201).json(cycle);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// PUT update heat cycle
router.put('/heat-cycles/:id', (req, res) => {
  try {
    const { start_date, end_date, progesterone_peak_date, breeding_date, breeding_successful, notes } = req.body;
    
    const db = getDatabase();
    db.prepare(`
      UPDATE heat_cycles 
      SET start_date = ?, end_date = ?, progesterone_peak_date = ?, 
          breeding_date = ?, breeding_successful = ?, notes = ?
      WHERE id = ?
    `).run(start_date, end_date, progesterone_peak_date, breeding_date, breeding_successful, notes, req.params.id);
    
    const cycle = db.prepare('SELECT * FROM heat_cycles WHERE id = ?').get(req.params.id);
    res.json(cycle);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// DELETE heat cycle
router.delete('/heat-cycles/:id', (req, res) => {
  try {
    const db = getDatabase();
    db.prepare('DELETE FROM heat_cycles WHERE id = ?').run(req.params.id);
    res.json({ message: 'Heat cycle deleted successfully' });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// GET calculate expected whelping date
router.get('/whelping-calculator', (req, res) => {
  try {
    const { breeding_date } = req.query;
    
    if (!breeding_date) {
      return res.status(400).json({ error: 'Breeding date is required' });
    }
    
    const breedDate = new Date(breeding_date);
    
    // Average gestation: 63 days, range 58-68 days
    const expectedDate = new Date(breedDate);
    expectedDate.setDate(expectedDate.getDate() + 63);
    
    const earliestDate = new Date(breedDate);
    earliestDate.setDate(earliestDate.getDate() + 58);
    
    const latestDate = new Date(breedDate);
    latestDate.setDate(latestDate.getDate() + 68);
    
    res.json({
      breeding_date: breeding_date,
      expected_whelping_date: expectedDate.toISOString().split('T')[0],
      earliest_date: earliestDate.toISOString().split('T')[0],
      latest_date: latestDate.toISOString().split('T')[0],
      gestation_days: 63
    });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

module.exports = router;