const express = require('express');
const router = express.Router();
const db = require('../database');
const imageProcessor = require('../image-processor');
const path = require('path');
const fs = require('fs').promises;
const storage = require('../storage');

// ================================================================
// GET /api/images/unique-clients - Buscar lista leve de clínicas
// ================================================================
router.get('/unique-clients', async (req, res) => {
  try {
    const clients = await db.all('SELECT DISTINCT client_name FROM images WHERE client_name IS NOT NULL');
    res.json(clients.map(c => c.client_name));
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// POST /api/images/upload - Envio Manual via Web
// ================================================================
router.post('/upload', async (req, res) => {
  try {
    const { imageBase64, patientData } = req.body;
    
    if (!imageBase64 || !patientData || !patientData.name) {
      return res.status(400).json({ error: 'Dados incompletos: imageBase64 e patientData.name são obrigatórios.' });
    }
    
    const base64Data = imageBase64.replace(/^data:image\/\w+;base64,/, "");
    const imageBuffer = Buffer.from(base64Data, 'base64');
    
    await imageProcessor.validateImage(imageBuffer);
    
    const clientName = 'Upload Manual';
    const patientName = patientData.name;
    const timestamp = Date.now();
    const guid = Math.random().toString(36).substring(2, 15);
    const filename = `${timestamp}_${guid}.png`;
    
    await storage.saveImage(filename, imageBuffer, clientName, patientName, false);
    
    let thumbFilename = null;
    try {
      const thumbBuffer = await imageProcessor.getThumbnail(imageBuffer, 500, 500);
      thumbFilename = `thumb_${filename}`;
      await storage.saveImage(thumbFilename, thumbBuffer, clientName, patientName, false);
    } catch (e) {
      console.error('Erro ao gerar thumbnail manual:', e);
    }
    
    const doctor = patientData.doctor || '';
    const remark = patientData.remark || '';
    
    const result = await db.run(
      `INSERT INTO images (
        image_guid, patient_name, client_name, original_filename, filename, thumb_filename, enabled, doctor, remark
      ) VALUES ($1, $2, $3, $4, $5, $6, 1, $7, $8)`,
      [guid, patientName, clientName, 'manual_upload.png', filename, thumbFilename, doctor, remark]
    );
    
    // Notificar clientes socket para atualizar galeria automaticamente
    if (req.app.get('io') || global.io) {
      const io = req.app.get('io') || global.io;
      if (io) io.emit('new-image', { filename: filename, thumb: thumbFilename, patientName: patientName });
    }
    
    res.json({ success: true });
  } catch (error) {
    console.error('Erro no upload manual:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// GET /api/images - Listar imagens
// ================================================================
router.get('/', async (req, res) => {
  try {
    const showDisabled = req.query.disabled === 'true';
    const search = req.query.search || '';
    const clientName = req.query.client || '';
    
    let query = `SELECT * FROM images WHERE enabled = $1`;
    let params = [showDisabled ? 0 : 1];
    let paramIndex = 2;
    
    if (clientName) {
      query += ` AND client_name = $${paramIndex++}`;
      params.push(clientName);
    }
    
    if (search) {
      query += ` AND (patient_name LIKE $${paramIndex} OR image_guid LIKE $${paramIndex + 1} OR filename LIKE $${paramIndex + 2})`;
      params.push(`%${search}%`, `%${search}%`, `%${search}%`);
      paramIndex += 3;
    }
    
    query += ` ORDER BY created_at DESC LIMIT 100`;
    
    const images = await db.all(query, params);
    res.json(images);
  } catch (error) {
    console.error('Erro ao listar imagens:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// GET /api/images/patients - Listar pacientes agrupados
// ================================================================
router.get('/patients', async (req, res) => {
  try {
    const showDisabled = req.query.disabled === 'true';
    const search = req.query.search || '';
    const clientName = req.query.client || '';
    const enabledVal = showDisabled ? 0 : 1;

    let paramIndex = 1;
    let where = `WHERE enabled = $${paramIndex++}`;
    let params = [enabledVal];
 
    if (clientName) {
      where += ` AND client_name = $${paramIndex}`;
      params.push(clientName);
      paramIndex++;
    }

    // Pagination
    const page = parseInt(req.query.page) || 1;
    const limit = parseInt(req.query.limit) || 50;
    const offset = (page - 1) * limit;
 
    if (search) {
      where += ` AND (patient_name LIKE $${paramIndex} OR image_guid LIKE $${paramIndex + 1})`;
      params.push(`%${search}%`, `%${search}%`);
      paramIndex += 2;
    }

    // Group by patient_name — pick thumbnail from most recent image
    const rows = await db.all(
      `SELECT
         patient_name,
         MAX(doctor) AS doctor,
         MAX(remark) AS remark,
         MAX(client_name) AS client_name,
         COUNT(*) AS image_count,
         MAX(created_at) AS last_date,
         (SELECT COALESCE(thumb_filename, filename) FROM images i2
          WHERE i2.patient_name = images.patient_name AND i2.enabled = ${enabledVal}
          ORDER BY i2.created_at DESC LIMIT 1) AS thumb_filename
       FROM images
       ${where}
       GROUP BY patient_name
       ORDER BY MAX(created_at) DESC
       LIMIT ${limit} OFFSET ${offset}`,
      params
    );

    // Converter thumb_filename para URL completa (Wasabi ou local)
    for (const row of rows) {
      if (row.thumb_filename) {
        try {
          const thumbUrl = await storage.getImageUrl(row.thumb_filename, row.client_name, row.patient_name);
          row.thumb_url = thumbUrl || `/uploads/${row.thumb_filename}`;
        } catch (e) {
          console.error('Erro ao gerar URL de thumbnail:', e);
          row.thumb_url = `/uploads/${row.thumb_filename}`;
        }
      } else {
        row.thumb_url = '';
      }
    }

    res.json(rows);
  } catch (error) {
    console.error('Erro ao listar pacientes:', error);
    res.status(500).json({ error: error.message });
  }
});


// ================================================================
// GET /api/images/by-patient - Imagens de um paciente
// ================================================================
router.get('/by-patient', async (req, res) => {
  try {
    const patientName = req.query.name || '';
    const showDisabled = req.query.disabled === 'true';

    if (!patientName) {
      return res.status(400).json({ error: 'Parâmetro name obrigatório' });
    }

    const images = await db.all(
      `SELECT * FROM images
       WHERE patient_name = $1 AND enabled = $2
       ORDER BY created_at DESC`,
      [patientName, showDisabled ? 0 : 1]
    );

    // Converter filenames para URLs completas (Wasabi ou local)
    for (const image of images) {
      try {
        if (image.filename) {
          const fileUrl = await storage.getImageUrl(image.filename, image.client_name, image.patient_name);
          image.file_url = fileUrl || `/uploads/${image.filename}`;
        }
        if (image.thumb_filename) {
          const thumbUrl = await storage.getImageUrl(image.thumb_filename, image.client_name, image.patient_name);
          image.thumb_url = thumbUrl || `/uploads/${image.thumb_filename}`;
        }
      } catch (e) {
        console.error('Erro ao gerar URL para imagem:', e);
        image.file_url = image.file_url || `/uploads/${image.filename}`;
        image.thumb_url = image.thumb_url || `/uploads/${image.thumb_filename}`;
      }
    }

    res.json(images);
  } catch (error) {
    console.error('Erro ao buscar imagens do paciente:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// DELETE /api/images/by-patient - Excluir todas imagens de um paciente
// ================================================================
router.delete('/by-patient', async (req, res) => {
  try {
    const patientName = req.query.name;
    if (!patientName) return res.status(400).json({ error: 'Parâmetro name obrigatório' });

    const images = await db.all('SELECT * FROM images WHERE patient_name = $1', [patientName]);
    
    for (const image of images) {
      await storage.deleteImage(image.filename, image.client_name, image.patient_name);
    }
    
    await db.run('DELETE FROM images WHERE patient_name = $1', [patientName]);
    res.json({ success: true, count: images.length });
  } catch (error) {
    console.error('Erro ao excluir imagens do paciente:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// GET /api/images/:id - Buscar imagem por ID
// ================================================================
router.get('/:id', async (req, res) => {
  try {
    const image = await db.get('SELECT * FROM images WHERE id = $1', [req.params.id]);
    if (!image) {
      return res.status(404).json({ error: 'Imagem não encontrada' });
    }
    res.json(image);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// GET /api/images/stats - Estatísticas
// ================================================================
router.get('/stats', async (req, res) => {
  try {
    const total = await db.get('SELECT COUNT(*) as count FROM images');
    const enabled = await db.get('SELECT COUNT(*) as count FROM images WHERE enabled = 1');
    const withTooth = await db.get('SELECT COUNT(*) as count FROM images WHERE tooth_number IS NOT NULL');
    
    res.json({
      total: total.count,
      enabled: enabled.count,
      disabled: total.count - enabled.count,
      withToothInfo: withTooth.count,
      withoutToothInfo: total.count - withTooth.count
    });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// GET /api/images/:id/transformations - Gerar transformações
// ================================================================
router.get('/:id/transformations', async (req, res) => {
  try {
    const image = await db.get('SELECT * FROM images WHERE id = $1', [req.params.id]);
    if (!image) {
      return res.status(404).json({ error: 'Imagem não encontrada' });
    }
    
    // Buscar a imagem original se esta é uma transformação
    const originalId = image.original_image_id || image.id;
    const originalImage = await db.get('SELECT * FROM images WHERE id = $1', [originalId]);
    
    let originalBuffer;
    try {
      originalBuffer = await storage.getImageBuffer(originalImage.filename, originalImage.client_name, originalImage.patient_name, false);
    } catch (e) {
      originalBuffer = await storage.getImageBuffer(originalImage.filename, originalImage.client_name, originalImage.patient_name, true);
    }
    
    const transformations = [
      { name: 'Original', rotation: 0, flipH: false, flipV: false },
      { name: 'Flip Horizontal', rotation: 0, flipH: true, flipV: false },
      { name: 'Flip Vertical', rotation: 0, flipH: false, flipV: true },
      { name: 'Rotação +90°', rotation: 90, flipH: false, flipV: false },
      { name: 'Rotação -90°', rotation: -90, flipH: false, flipV: false }
    ];
    
    const results = [];
    for (const t of transformations) {
      try {
        let processed = await imageProcessor.rotate(originalBuffer, t.rotation);
        processed = await imageProcessor.flip(processed, t.flipH, t.flipV);
        const base64 = `data:image/png;base64,${processed.toString('base64')}`;
        
        results.push({
          ...t,
          base64,
          size: processed.length
        });
      } catch (error) {
        console.error(`Erro ao processar transformação ${t.name}:`, error);
      }
    }
    
    res.json(results);
  } catch (error) {
    console.error('Erro ao gerar transformações:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// POST /api/images/:id/transform - Salvar transformação
// ================================================================
router.post('/:id/transform', async (req, res) => {
  try {
    const { rotation, flipH, flipV, remark } = req.body;
    const originalImage = await db.get('SELECT * FROM images WHERE id = $1', [req.params.id]);
    
    if (!originalImage) {
      return res.status(404).json({ error: 'Imagem não encontrada' });
    }
    
    // Buscar a imagem original real se esta é uma transformação
    const realOriginalId = originalImage.original_image_id || originalImage.id;
    const realOriginal = await db.get('SELECT * FROM images WHERE id = $1', [realOriginalId]);
    
    // Processar a imagem
    let originalBuffer;
    try {
      originalBuffer = await storage.getImageBuffer(realOriginal.filename, realOriginal.client_name, realOriginal.patient_name, false);
    } catch (e) {
      originalBuffer = await storage.getImageBuffer(realOriginal.filename, realOriginal.client_name, realOriginal.patient_name, true);
    }
    
    let processed = await imageProcessor.rotate(originalBuffer, rotation);
    processed = await imageProcessor.flip(processed, flipH, flipV);
    
    // Salvar nova versão em processed (local e nuvem)
    const timestamp = Date.now();
    const processedFilename = `${realOriginal.image_guid}_${timestamp}.png`;
    await storage.saveImage(processedFilename, processed, realOriginal.client_name, realOriginal.patient_name, true);
    
    // Desabilitar a imagem active atual para que não fique duplicada na interface
    await db.run('UPDATE images SET enabled = 0 WHERE id = $1', [req.params.id]);
 
    const newRemark = remark !== undefined ? remark : originalImage.remark;
    
    // Inserir a nova imagem como a versão ativa
    const result = await db.run(
      `INSERT INTO images (
        image_guid, patient_name, client_name, original_filename, filename, 
        enabled, rotation, flip_horizontal, flip_vertical, original_image_id, created_at, remark, doctor
      ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13)`,
      [
        `${realOriginal.image_guid}_${timestamp}`,
        realOriginal.patient_name,
        realOriginal.client_name,
        realOriginal.filename,
        processedFilename,
        1, // Nova imagem fica ativa
        rotation,
        flipH ? 1 : 0,
        flipV ? 1 : 0,
        realOriginalId,
        originalImage.created_at, // Manter a data de criação original
        newRemark,
        realOriginal.doctor
      ]
    );
    
    res.json({ 
      success: true, 
      imageId: result.lastID,
      message: 'Orientação atualizada com sucesso!'
    });
  } catch (error) {
    console.error('Erro ao salvar transformação:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// PUT /api/images/:id/patient-info - Atualizar dados do paciente
// ================================================================
router.put('/:id/patient-info', async (req, res) => {
  try {
    const { patientNameResumed, toothNumber, toothSide } = req.body;
    
    await db.run(
      `UPDATE images SET 
        patient_name_resumed = $1, 
        tooth_number = $2, 
        tooth_side = $3,
        enabled = 1
      WHERE id = $4`,
      [patientNameResumed, toothNumber, toothSide, req.params.id]
    );
    
    res.json({ success: true, message: 'Dados do paciente atualizados!' });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// GET /api/images/:id/download - Download da imagem
// ================================================================
router.get('/:id/download', async (req, res) => {
  try {
    const image = await db.get('SELECT * FROM images WHERE id = $1', [req.params.id]);
    if (!image) {
      return res.status(404).json({ error: 'Imagem não encontrada' });
    }
    
    // Nome: nome-resumido_numero_lado.png
    if (image.patient_name_resumed && image.tooth_number && image.tooth_side) {
      const filename = `${image.patient_name_resumed}_${image.tooth_number}_${image.tooth_side}.png`;
      
      const filePath = path.join(__dirname, '../processed', image.filename);
      
      res.setHeader('Content-Disposition', `attachment; filename="${filename}"`);
      res.download(filePath, filename);
    } else {
      res.status(400).json({ error: 'Dados do paciente incompletos' });
    }
  } catch (error) {
    console.error('Erro no download:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// DELETE /api/images/:id - Apagar versão da imagem
// ================================================================
router.delete('/:id', async (req, res) => {
  try {
    const image = await db.get('SELECT * FROM images WHERE id = $1', [req.params.id]);
    if (!image) {
      return res.status(404).json({ error: 'Imagem não encontrada' });
    }
    
    // NUNCA apagar a original
    if (!image.original_image_id) {
      return res.status(400).json({ 
        error: 'Não é possível apagar a imagem original',
        code: 'ORIGINAL_NOT_DELETABLE'
      });
    }
    
    // Apagar arquivo local e do S3
    await storage.deleteImage(image.filename, image.client_name, image.patient_name);
    
    // Apagar do banco
    await db.run('DELETE FROM images WHERE id = $1', [req.params.id]);
    
    res.json({ success: true, message: 'Imagem apagada com sucesso' });
  } catch (error) {
    console.error('Erro ao apagar imagem:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// GET /api/images/:id/file-url — Retorna a URL de visualização
// full-res de uma imagem (para o painel Original do modal)
// ================================================================
router.get('/:id/file-url', async (req, res) => {
  try {
    const image = await db.get('SELECT filename, client_name, patient_name FROM images WHERE id = $1', [req.params.id]);
    if (!image) return res.status(404).json({ error: 'Imagem não encontrada' });

    let url;
    if (image.filename.startsWith('http')) {
      url = image.filename;
    } else {
      // Se o arquivo está no Wasabi, reconstroem a URL
      try {
        const wasabiUrl = await storage.getImageUrl(image.filename, image.client_name, image.patient_name);
        url = wasabiUrl || `/uploads/${image.filename}`;
      } catch (e) {
        console.error('Erro ao gerar URL Wasabi:', e);
        url = `/uploads/${image.filename}`;
      }
    }
    res.json({ url });
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

// ================================================================
// PUT /api/images/:id/toggle-enabled - Habilitar/Desabilitar
// ================================================================
router.put('/:id/toggle-enabled', async (req, res) => {
  try {
    const image = await db.get('SELECT * FROM images WHERE id = $1', [req.params.id]);
    if (!image) {
      return res.status(404).json({ error: 'Imagem não encontrada' });
    }
    
    const newEnabled = image.enabled ? 0 : 1;
    await db.run('UPDATE images SET enabled = $1 WHERE id = $2', [newEnabled, req.params.id]);
    
    res.json({ success: true, enabled: newEnabled === 1 });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// POST /api/images/backfill-thumbs — Gera thumbnails para imagens
// que ainda não têm thumb_filename. Roda em background; retorna
// imediatamente com o total de imagens na fila.
// ================================================================
router.post('/backfill-thumbs', async (req, res) => {
  try {
    const rows = await db.all(
      `SELECT id, filename, client_name, patient_name
       FROM images
       WHERE thumb_filename IS NULL AND enabled = true
       ORDER BY created_at DESC`
    );
    res.json({ queued: rows.length, message: 'Backfill iniciado em background' });
    // Processa sem bloquear a resposta
    setImmediate(() => runThumbBackfill(rows));
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

async function runThumbBackfill(rows) {
  const UPLOAD_DIR   = process.env.UPLOAD_DIR   || path.join(__dirname, '..', '..', 'uploads');
  const PROCESSED_DIR = process.env.PROCESSED_DIR || path.join(__dirname, '..', '..', 'processed');
  let done = 0, failed = 0;
  for (const row of rows) {
    try {
      // Tenta carregar a imagem do disco local
      let imgBuffer = null;
      for (const dir of [UPLOAD_DIR, PROCESSED_DIR]) {
        try { imgBuffer = await fs.readFile(path.join(dir, row.filename)); break; } catch (_) {}
      }
      if (!imgBuffer) { failed++; continue; }
      const thumbBuffer   = await imageProcessor.getThumbnail(imgBuffer);
      const thumbFilename = `thumb_${row.filename.replace(/\.[^.]+$/, '')}.jpg`;
      await storage.saveImage(thumbFilename, thumbBuffer, row.client_name, row.patient_name, false);
      await db.run('UPDATE images SET thumb_filename = $1 WHERE id = $2', [thumbFilename, row.id]);
      done++;
    } catch (e) {
      failed++;
    }
  }
  console.log(`[backfill-thumbs] concluído: ${done} geradas, ${failed} falhas de ${rows.length} total`);
}

// Exporta a função para ser chamada no boot do servidor
module.exports = router;
module.exports.runThumbBackfill = runThumbBackfill;