let profile = null;
let entries = [];

document.addEventListener('DOMContentLoaded', () => {
  document.getElementById('entryDate').valueAsDate = new Date();
  document.getElementById('filterDate').valueAsDate = new Date();
  loadProfile();
  loadEntries();
});

document.getElementById('profileForm').addEventListener('submit', async (e) => {
  e.preventDefault();
  
  const gender = document.getElementById('gender').value;
  const age = parseInt(document.getElementById('age').value);
  const height = parseInt(document.getElementById('height').value);
  const weight = parseInt(document.getElementById('weight').value);
  const activity = parseFloat(document.getElementById('activity').value);
  const goal = document.getElementById('goal').value;

  let bmr;
  if (gender === 'male') {
    bmr = 88.362 + (13.397 * weight) + (4.799 * height) - (5.677 * age);
  } else {
    bmr = 447.593 + (9.247 * weight) + (3.098 * height) - (4.330 * age);
  }

  const tdee = Math.round(bmr * activity);
  let goalCalories;
  if (goal === 'lose') {
    goalCalories = Math.round(tdee * 0.8);
  } else if (goal === 'gain') {
    goalCalories = Math.round(tdee * 1.15);
  } else {
    goalCalories = tdee;
  }

  profile = { gender, age, height, weight, activity, goal, bmr: Math.round(bmr), tdee, goalCalories };
  
  await fetch('/api/profile', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(profile)
  });

  document.getElementById('bmrValue').textContent = Math.round(bmr) + ' ккал';
  document.getElementById('tdeeValue').textContent = tdee + ' ккал';
  document.getElementById('goalValue').textContent = goalCalories + ' ккал';
  document.getElementById('result').style.display = 'block';
  document.getElementById('goalCalories').textContent = goalCalories + ' ккал';
  
  updateStats();
});

document.getElementById('entryForm').addEventListener('submit', async (e) => {
  e.preventDefault();
  
  const entry = {
    foodName: document.getElementById('foodName').value,
    calories: parseInt(document.getElementById('calories').value),
    protein: parseFloat(document.getElementById('protein').value) || 0,
    fat: parseFloat(document.getElementById('fat').value) || 0,
    carbs: parseFloat(document.getElementById('carbs').value) || 0,
    date: document.getElementById('entryDate').value
  };

  await fetch('/api/entries', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(entry)
  });

  document.getElementById('foodName').value = '';
  document.getElementById('calories').value = '';
  document.getElementById('protein').value = '';
  document.getElementById('fat').value = '';
  document.getElementById('carbs').value = '';

  loadEntries();
});

async function loadProfile() {
  const res = await fetch('/api/profile');
  profile = await res.json();
  if (profile) {
    document.getElementById('gender').value = profile.gender;
    document.getElementById('age').value = profile.age;
    document.getElementById('height').value = profile.height;
    document.getElementById('weight').value = profile.weight;
    document.getElementById('activity').value = profile.activity;
    document.getElementById('goal').value = profile.goal;
    document.getElementById('goalCalories').textContent = profile.goalCalories + ' ккал';
    updateStats();
  }
}

async function loadEntries() {
  const res = await fetch('/api/entries');
  entries = await res.json();
  renderEntries(entries);
  updateStats();
}

function renderEntries(entriesToRender) {
  const container = document.getElementById('entriesList');
  
  if (entriesToRender.length === 0) {
    container.innerHTML = '<div class="empty-state">Пока нет записей. Добавь первую!</div>';
    return;
  }

  const sorted = [...entriesToRender].sort((a, b) => new Date(b.date) - new Date(a.date));
  
  container.innerHTML = sorted.map(entry => `
    <div class="entry-item">
      <div class="entry-info">
        <div class="entry-name">${escapeHtml(entry.foodName)}</div>
        <div class="entry-details">${formatDate(entry.date)}</div>
        <div class="entry-macros">Б: ${entry.protein}г | Ж: ${entry.fat}г | У: ${entry.carbs}г</div>
      </div>
      <span class="entry-calories">${entry.calories} ккал</span>
      <span class="entry-date">${formatDate(entry.date)}</span>
      <button onclick="deleteEntry(${entry.id})" class="btn btn-danger">Удалить</button>
    </div>
  `).join('');
}

function deleteEntry(id) {
  if (confirm('Удалить эту запись?')) {
    fetch('/api/entries', {
      method: 'DELETE',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ id })
    }).then(loadEntries);
  }
}

function filterByDate() {
  const date = document.getElementById('filterDate').value;
  const filtered = entries.filter(e => e.date === date);
  renderEntries(filtered);
}

function clearFilter() {
  renderEntries(entries);
}

function updateStats() {
  if (!profile) return;
  
  const today = new Date().toISOString().split('T')[0];
  const todayEntries = entries.filter(e => e.date === today);
  const todayCalories = todayEntries.reduce((sum, e) => sum + e.calories, 0);
  
  document.getElementById('todayCalories').textContent = todayCalories + ' ккал';
  document.getElementById('goalCalories').textContent = profile.goalCalories + ' ккал';
  
  const remaining = profile.goalCalories - todayCalories;
  const remainingEl = document.getElementById('remainingCalories');
  remainingEl.textContent = remaining + ' ккал';
  remainingEl.style.color = remaining >= 0 ? '#10b981' : '#ef4444';
}

function exportCsv() {
  if (entries.length === 0) {
    alert('Нет записей для экспорта');
    return;
  }
  
  const head = ['Дата', 'Продукт', 'Ккал', 'Белки (г)', 'Жиры (г)', 'Углеводы (г)'];
  const body = entries.map(e => [
    e.date,
    '"' + e.foodName.replace(/"/g, '""') + '"',
    e.calories,
    e.protein,
    e.fat,
    e.carbs
  ].join(';'));
  
  const csv = '\uFEFF' + [head.join(';'), ...body].join('\n');
  const blob = new Blob([csv], { type: 'text/csv;charset=utf-8;' });
  const url = URL.createObjectURL(blob);
  const a = document.createElement('a');
  a.href = url;
  a.download = 'dnevnik_pitaniya.csv';
  a.click();
  URL.revokeObjectURL(url);
}

function escapeHtml(text) {
  const div = document.createElement('div');
  div.textContent = text;
  return div.innerHTML;
}

function formatDate(dateStr) {
  const [year, month, day] = dateStr.split('-');
  return `${day}.${month}.${year}`;
}