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

async function emitAndAwaitAck(io, action, payload) {
  if (!io) return { success: true, warning: 'Socket.IO não inicializado no servidor.' };
  
  const eventId = crypto.randomUUID();
  payload.eventId = eventId;
  payload.action = action;
  
  const ackPromise = new Promise((resolve) => {
    if (global.pendingAcks) {
      global.pendingAcks.set(eventId, resolve);
      setTimeout(() => {
        if (global.pendingAcks.has(eventId)) {
          global.pendingAcks.delete(eventId);
          resolve(null); // Timeout
        }
      }, 4000);
    } else {
      resolve(null);
    }
  });

  io.emit('remote-crud-patient', payload);
  
  const result = await ackPromise;
  if (result && result.success) {
    return { success: true, message: `Sincronizado com PC: ${result.pcName || 'Desconhecido'}`, ackInfo: result };
  } else if (result && !result.success) {
    return { success: true, warning: `Erro no app Windows (${result.pcName || 'Desconhecido'}): ${result.error || 'Erro local'}` };
  } else {
    return { success: true, warning: 'Salvo na nuvem, porém o App Windows não respondeu. Verifique o PC do app client Windows ou nome do PC - o app pode estar atualizando, o PC desligado, o app fechado ou sem internet no PC ou clínica.' };
  }
}

// ================================================================
// 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 clinicName = 'Upload Manual';
    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, clinicName, clientName, patientName, false);

    let thumbFilename = null;
    try {
      const thumbBuffer = await imageProcessor.getThumbnail(imageBuffer, 500, 500);
      thumbFilename = `thumb_${filename}`;
      await storage.saveImage(thumbFilename, thumbBuffer, clinicName, 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, clinic_name, client_name, original_filename, filename, thumb_filename, enabled, doctor, remark
      ) VALUES ($1, $2, $3, $4, $5, $6, $7, 1, $8, $9)`,
      [guid, patientName, clinicName, 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 id FROM images i2
          WHERE i2.patient_name = images.patient_name AND i2.enabled = ${enabledVal}
          ORDER BY i2.created_at DESC LIMIT 1) AS latest_image_id,
         (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
    );

    for (const row of rows) {
      row.thumb_url = row.latest_image_id ? `/api/images/${row.latest_image_id}/thumbnail` : '';
    }

    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]
    );

    // Adicionar lazy-load URLs (não fazer requisições async aqui)
    for (const image of images) {
      image.file_url = `/api/images/${image.id}/file-url`;
      image.thumb_url = `/api/images/${image.id}/thumbnail`;
    }

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

// ================================================================
// POST /api/images/patients - Criar paciente
// Insere um registro "fantasma" (enabled=0) para manter os dados
// ================================================================
router.post('/patients', async (req, res) => {
  try {
    const { firstName, lastName, doctor, birthday, gender, phone, remark } = req.body;
    const fullName = `${firstName || ''} ${lastName || ''}`.trim();
    if (!fullName) return res.status(400).json({ error: 'Nome obrigatório' });

    const dummyGuid = crypto.randomUUID();

    await db.run(
      `INSERT INTO images (
        image_guid, patient_name, doctor, remark, enabled, filename, original_filename
      ) VALUES ($1, $2, $3, $4, 0, $5, $6)`,
      [
        dummyGuid,
        fullName,
        doctor || null,
        remark || null,
        'dummy_patient_record',
        'dummy_patient_record'
      ]
    );

    const io = req.app.get('io') || global.io;
    const syncResult = await emitAndAwaitAck(io, 'create', {
      patient: { id: dummyGuid, firstName, lastName, doctor, birthday, gender, phone, remark, fullName }
    });

    res.json(syncResult);
  } catch (error) {
    console.error('Erro ao criar paciente:', error);
    res.status(500).json({ error: error.message });
  }
});

// ================================================================
// PUT /api/images/patients/:name - Editar dados de um paciente
// Atualiza patient_name, doctor e remark em todas as imagens do paciente.
// ================================================================
router.put('/patients/:name', async (req, res) => {
  try {
    const oldName = decodeURIComponent(req.params.name);
    const { newName, doctor, remark } = req.body;

    if (!oldName) return res.status(400).json({ error: 'Nome do paciente obrigatório.' });

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

    if (newName !== undefined && newName.trim() !== '') {
      updates.push(`patient_name = $${i++}`);
      params.push(newName.trim());
    }
    if (doctor !== undefined) {
      updates.push(`doctor = $${i++}`);
      params.push(doctor);
    }
    if (remark !== undefined) {
      updates.push(`remark = $${i++}`);
      params.push(remark);
    }

    if (updates.length === 0) return res.status(400).json({ error: 'Nenhum campo para atualizar.' });

    params.push(oldName);
    const result = await db.run(
      `UPDATE images SET ${updates.join(', ')} WHERE patient_name = $${i}`,
      params
    );

    const io = req.app.get('io') || global.io;
    const syncResult = await emitAndAwaitAck(io, 'update', {
      oldName: oldName,
      patient: { newName: newName?.trim(), doctor, remark }
    });
    
    res.json({ ...syncResult, updated: result.changes });
  } catch (error) {
    console.error('Erro ao editar 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.clinic_name, image.client_name, image.patient_name);
    }

    await db.run('DELETE FROM images WHERE patient_name = $1', [patientName]);

    const io = req.app.get('io') || global.io;
    const syncResult = await emitAndAwaitAck(io, 'delete', { patientName });

    res.json({ ...syncResult, 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.clinic_name, originalImage.client_name, originalImage.patient_name, false);
    } catch (e) {
      originalBuffer = await storage.getImageBuffer(originalImage.filename, originalImage.clinic_name, 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, image_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.clinic_name, realOriginal.client_name, realOriginal.patient_name, false);
    } catch (e) {
      originalBuffer = await storage.getImageBuffer(realOriginal.filename, realOriginal.clinic_name, 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.clinic_name, 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 newImageRemark = image_remark !== undefined ? image_remark : originalImage.image_remark;
    
    // Inserir a nova imagem como a versão ativa
    const result = await db.run(
      `INSERT INTO images (
        image_guid, patient_name, clinic_name, client_name, original_filename, filename,
        enabled, rotation, flip_horizontal, flip_vertical, original_image_id, created_at, remark, image_remark, doctor
      ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15) RETURNING id`,
      [
        `${realOriginal.image_guid}_${timestamp}`,
        realOriginal.patient_name,
        realOriginal.clinic_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
        originalImage.remark, // Manter a observação do paciente intacta
        newImageRemark, // A observação específica da imagem
        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/remark - Atualizar observação da imagem
// ================================================================
router.put('/:id/remark', async (req, res) => {
  try {
    const { image_remark } = req.body;
    await db.run(
      'UPDATE images SET image_remark = $1 WHERE id = $2',
      [image_remark, req.params.id]
    );
    res.json({ success: true, message: 'Observação da imagem atualizada!' });
  } catch (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.clinic_name, 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, clinic_name, 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.clinic_name, 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, clinic_name, client_name, patient_name
       FROM images
       WHERE thumb_filename IS NULL AND enabled = 1
       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) {
  let done = 0, failed = 0;
  for (const row of rows) {
    try {
      // Busca a original via storage (disco local → Wasabi com path correto → fallback 'Desconhecido')
      let imgBuffer = null;
      try {
        imgBuffer = await storage.getImageBuffer(row.filename, row.clinic_name, row.client_name, row.patient_name);
      } catch (_) {}

      // Fallback legado: uploads antigos foram gravados com patientName='Desconhecido' no Wasabi
      if (!imgBuffer && row.patient_name !== 'Desconhecido') {
        try {
          imgBuffer = await storage.getImageBuffer(row.filename, row.clinic_name, row.client_name, 'Desconhecido');
        } catch (_) {}
      }

      if (!imgBuffer) { failed++; continue; }

      const thumbBuffer   = await imageProcessor.getThumbnail(imgBuffer);
      const thumbFilename = `thumb_${row.filename.replace(/\.[^.]+$/, '')}.jpg`;
      await storage.saveImage(thumbFilename, thumbBuffer, row.clinic_name, row.client_name, row.patient_name, false);
      await db.run('UPDATE images SET thumb_filename = $1 WHERE id = $2', [thumbFilename, row.id]);
      done++;
      console.log(`[backfill-thumbs] ✅ id ${row.id}: ${thumbFilename}`);
    } catch (e) {
      console.error(`[backfill-thumbs] ❌ id ${row.id}:`, e.message);
      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;