// ============================================
// 通用列表管理 - 无限滚动加载
// ============================================

const config = {
  orderList: { endpoint: '/api/records/orders', emptyMsg: '暂无接单记录', renderItem: renderOrderItem },
  otherIncomeList: { endpoint: '/api/records/other-income', emptyMsg: '暂无红包及其他收入记录', renderItem: renderOtherIncomeItem },
  dispatchList: { endpoint: '/api/records/dispatches', emptyMsg: '暂无派单记录', renderItem: renderDispatchItem },
  redEnvelopeList: { endpoint: '/api/records/red-envelope', emptyMsg: '暂无红包收入记录', renderItem: renderRedEnvelopeItem },
  milkTeaList: { endpoint: '/api/records/milk-tea', emptyMsg: '暂无奶茶收入记录', renderItem: renderMilkTeaItem }
};

const PAGE_SIZE = 20;

const listState = {};

function initList(listId) {
  listState[listId] = {
    loading: false,
    records: [],
    page: 1,
    hasMore: true,
    totalCount: 0
  };

  const container = document.getElementById(listId);
  if (container) container.innerHTML = '';
}

async function loadListData(listId) {
  const cfg = config[listId];
  const state = listState[listId];
  if (!cfg || !state) return;

  if (state.loading || !state.hasMore) return;

  state.loading = true;
  showLoading(listId, true);

  try {
    const res = await fetch(
      API + cfg.endpoint + '?page=' + state.page + '&limit=' + PAGE_SIZE + '&year=' + currentYear + '&month=' + currentMonth,
      { headers: headers() }
    );

    if (!res.ok) {
      console.error('[loadListData] fetch failed:', res.status);
      state.loading = false;
      showLoading(listId, false);
      return;
    }

    const data = await res.json();
    const newRecords = data.records || [];
    const total = data.total || 0;

    state.records = state.records.concat(newRecords);
    state.totalCount = total;
    state.hasMore = state.records.length < total;
    state.page++;

    renderList(listId);
    setupScrollObserver(listId);
  } catch (e) {
    console.error('[loadListData] error:', e);
  } finally {
    state.loading = false;
    showLoading(listId, false);
  }
}

function showLoading(listId, show) {
  const loadingId = listId.replace('List', 'Loading');
  const loadingEl = document.getElementById(loadingId);
  if (loadingEl) {
    loadingEl.style.display = show ? 'block' : 'none';
    if (!show && listState[listId]) {
      const state = listState[listId];
      if (state.hasMore) {
        loadingEl.textContent = '下拉加载更多...';
      } else if (state.records.length > 0) {
        loadingEl.textContent = '已加载全部';
      } else {
        loadingEl.textContent = '';
      }
    }
  }
}

function renderList(listId) {
  const cfg = config[listId];
  const state = listState[listId];
  if (!cfg || !state) return;

  const container = document.getElementById(listId);
  if (!container) return;

  if (state.records.length === 0) {
    container.innerHTML = '<div class="ranking-empty">' + cfg.emptyMsg + '</div>';
    return;
  }

  const grouped = {};
  state.records.forEach(r => {
    const date = formatLocalDate(r.created_at);
    if (!grouped[date]) grouped[date] = [];
    grouped[date].push(r);
  });

  container.innerHTML = '';

  for (const [date, records] of Object.entries(grouped)) {
    const group = document.createElement('div');
    group.className = 'order-date-group';
    group.setAttribute('data-date', date);

    const label = document.createElement('div');
    label.className = 'order-date-label';
    label.textContent = date;
    group.appendChild(label);

    records.forEach(r => {
      const item = document.createElement('div');
      item.innerHTML = cfg.renderItem(r);
      group.appendChild(item.firstChild);
    });

    container.appendChild(group);
  }
}

function setupScrollObserver(listId) {
  const state = listState[listId];
  if (!state || !state.hasMore) return;

  const container = document.getElementById(listId);
  if (!container) return;

  // 移除旧的 sentinel
  const oldSentinel = container.querySelector('.scroll-sentinel');
  if (oldSentinel) oldSentinel.remove();

  // 创建新的 sentinel
  const sentinel = document.createElement('div');
  sentinel.className = 'scroll-sentinel';
  sentinel.style.height = '1px';
  container.appendChild(sentinel);

  const observer = new IntersectionObserver((entries) => {
    if (entries[0].isIntersecting && !state.loading && state.hasMore) {
      loadListData(listId);
    }
  }, { rootMargin: '100px' });

  observer.observe(sentinel);

  // 存储 observer 以便清理
  state.observer = observer;
}

// ============================================
// 兼容接口
// ============================================
async function loadOrders() { return loadListData('orderList'); }
async function loadOtherIncome() { return loadListData('otherIncomeList'); }
async function loadDispatches() { return loadListData('dispatchList'); }
async function loadRedEnvelope() { return loadListData('redEnvelopeList'); }
async function loadMilkTea() { return loadListData('milkTeaList'); }

// ============================================
// 渲染函数
// ============================================

function renderOrderItem(r) {
  const time = formatLocalTime(r.created_at);
  return '<div class="order-item" onclick=\'openEditModal(' + JSON.stringify(r).replace(/'/g, "&#39;") + ')\'>' +
    '<div class="order-item-top"><span class="order-item-boss">' + (r.boss || '-') + '</span><span class="order-item-amount">' + (r.amount || 0).toFixed(2) + '</span></div>' +
    '<div class="order-item-bottom"><span>' + (r.quantity || 0) + '单 × ' + (r.unit_price || 0).toFixed(2) + '</span><span>' + time + (r.partner ? ' · ' + r.partner : '') + '</span></div></div>';
}

function renderOtherIncomeItem(r) {
  const time = formatLocalTime(r.created_at);
  const displayCategory = r.category === '红包收入' ? '红包' : (r.category || '-');
  return '<div class="order-item" onclick=\'openEditModal(' + JSON.stringify(r).replace(/'/g, "&#39;") + ')\'>' +
    '<div class="order-item-top"><span class="order-item-boss">' + displayCategory + (r.boss ? ' · ' + r.boss : '') + '</span><span class="order-item-amount">' + (r.amount || 0).toFixed(2) + '</span></div>' +
    '<div class="order-item-bottom"><span>' + (r.source || '') + '</span><span>' + time + '</span></div></div>';
}

function renderDispatchItem(r) {
  const time = formatLocalTime(r.created_at);
  const unitPrice = r.unit_price || (r.quantity ? r.amount / r.quantity : 0);
  return '<div class="order-item" onclick=\'openEditModal(' + JSON.stringify(r).replace(/'/g, "&#39;") + ')\'>' +
    '<div class="order-item-top"><span class="order-item-boss">' + (r.boss || '-') + '</span><span class="order-item-amount">' + (r.amount || 0).toFixed(2) + '</span></div>' +
    '<div class="order-item-bottom"><span>' + (r.quantity || 0) + '单 × ' + (r.rebate || 0).toFixed(2) + '（单价' + unitPrice.toFixed(2) + '）</span><span>' + time + (r.partner ? ' · ' + r.partner : '') + '</span></div></div>';
}

function renderRedEnvelopeItem(r) {
  const time = formatLocalTime(r.created_at);
  return '<div class="order-item" onclick=\'openEditModal(' + JSON.stringify(r).replace(/'/g, "&#39;") + ')\'>' +
    '<div class="order-item-top"><span class="order-item-boss">红包</span><span class="order-item-amount">' + (r.amount || 0).toFixed(2) + '</span></div>' +
    '<div class="order-item-bottom"><span>' + (r.source || '') + '</span><span>' + time + '</span></div></div>';
}

function renderMilkTeaItem(r) {
  const time = formatLocalTime(r.created_at);
  return '<div class="order-item" onclick=\'openEditModal(' + JSON.stringify(r).replace(/'/g, "&#39;") + ')\'>' +
    '<div class="order-item-top"><span class="order-item-boss">奶茶</span><span class="order-item-amount">' + (r.amount || 0).toFixed(2) + '</span></div>' +
    '<div class="order-item-bottom"><span>' + (r.source || '') + '</span><span>' + time + '</span></div></div>';
}