let pickerYear = currentYear;
let pickerMonth = currentMonth;

function openMonthPicker() {
  pickerYear = currentYear;
  pickerMonth = currentMonth;
  renderMonthPicker();
  document.getElementById('monthPickerOverlay').classList.add('show');
}

function closeMonthPicker() {
  document.getElementById('monthPickerOverlay').classList.remove('show');
}

function changePickerYear(delta) {
  pickerYear += delta;
  renderMonthPicker();
}

function renderMonthPicker() {
  document.getElementById('pickerYearDisplay').textContent = pickerYear;
  const grid = document.getElementById('pickerMonthGrid');
  grid.innerHTML = '';
  for (let m = 1; m <= 12; m++) {
    const btn = document.createElement('button');
    btn.textContent = m + '月';
    if (m === pickerMonth) btn.classList.add('active');
    btn.onclick = () => {
      pickerMonth = m;
      grid.querySelectorAll('button').forEach(b => b.classList.remove('active'));
      btn.classList.add('active');
    };
    grid.appendChild(btn);
  }
}

function confirmMonth() {
  currentYear = pickerYear;
  currentMonth = pickerMonth;
  updateMonthDisplay();
  closeMonthPicker();
  loadStats();
}