const { getLayout } = require('../../utils/layout');
// pages/timeline/timeline.js
const { api, getImageUrl } = require('../../utils/request');

// 重复周期映射
var repeatUnitMap = { 'day': '天', 'week': '周', 'month': '月', 'year': '年' };

// 计算距离今天最近的重复日期（返回 Date 对象，已归零）
function calcNearestRepeatDate(eventDate, today, interval, unit) {
  var base = new Date(eventDate);
  base.setHours(0,0,0,0);
  if (unit === 'day') {
    var diff = Math.floor((today - base) / 86400000);
    var cycles = Math.floor(diff / interval);
    var nearest = new Date(base.getTime() + cycles * interval * 86400000);
    nearest.setHours(0,0,0,0);
    if (nearest > today) {
      nearest = new Date(nearest.getTime() - interval * 86400000);
      nearest.setHours(0,0,0,0);
    }
    return nearest;
  } else if (unit === 'week') {
    var diff = Math.floor((today - base) / 86400000);
    var cycles = Math.floor(diff / (7 * interval));
    var nearest = new Date(base.getTime() + cycles * 7 * interval * 86400000);
    nearest.setHours(0,0,0,0);
    if (nearest > today) {
      nearest = new Date(nearest.getTime() - 7 * interval * 86400000);
      nearest.setHours(0,0,0,0);
    }
    return nearest;
  } else if (unit === 'month') {
    var nearest = new Date(base);
    nearest.setHours(0,0,0,0);
    while (true) {
      var next = new Date(nearest);
      next.setMonth(next.getMonth() + interval);
      next.setHours(0,0,0,0);
      if (next > today) break;
      nearest = next;
    }
    return nearest;
  } else if (unit === 'year') {
    var nearest = new Date(base);
    nearest.setHours(0,0,0,0);
    while (true) {
      var next = new Date(nearest);
      next.setFullYear(next.getFullYear() + interval);
      next.setHours(0,0,0,0);
      if (next > today) break;
      nearest = next;
    }
    return nearest;
  }
  return new Date(eventDate);
}

Page({
  onResize: function() { this.setData(getLayout()); },
  data: { loading: true, loadError: false,
    list: []
  },

  onLoad: function() {
    this.setData(getLayout());
    this.loadData();
  },
  onShow: function() {
    this.loadData();
  },

  onPullDownRefresh: async function() {
    await this.loadData();
    wx.stopPullDownRefresh();
  },

  onShareAppMessage: function() {
    return { title: '让所有的爱有迹可循', path: '/pages/timeline/timeline', imageUrl: '/images/share.png' };
  },
  onShareTimeline: function() {
    return { title: '让所有的爱有迹可循', imageUrl: '/images/share.png' };
  },

  loadData: async function() {
    if (this._pageLoading) return;
    this._pageLoading = true;
    this.setData({loading:true, loadError:false});
    try {
      const list = await api.timelineList();
      const myUid = wx.getStorageSync('userId');
      var nameMap = {};
      var avatarMap = {};
      try {
        const info = await api.coupleInfo();
        var p1 = info.partner1 || {};
        var p2 = info.partner2 || {};
        if (p1.id) { nameMap[p1.id] = p1.nickname || p1.username || 'TA'; avatarMap[p1.id] = getImageUrl(p1.avatar); }
        if (p2.id) { nameMap[p2.id] = p2.nickname || p2.username || 'TA'; avatarMap[p2.id] = getImageUrl(p2.avatar); }
      } catch (e) {}

      var today = new Date(); today.setHours(0,0,0,0);
      var items = (list || []).map(function(item, idx) {
        var cid = parseInt(item.created_by) || 0;
        item.creator_name = nameMap[cid] || (cid == myUid ? '我' : 'TA');
        item.creator_avatar = avatarMap[cid] || '';
        item.creator_initial = (item.creator_name || '?')[0].toUpperCase();
        item.side = idx % 2 === 0 ? 'left' : 'right';
        item.bg_image_url = item.bg_image ? getImageUrl(item.bg_image) : '';

        // 计算纪念日/倒数日（支持重复事件）
        if (item.event_date) {
          var ed = new Date(item.event_date.replace(/-/g, '/'));
          ed.setHours(0,0,0,0);
          var repeatInterval = parseInt(item.repeat_interval) || 0;
          var repeatUnit = item.repeat_unit || '';

          // 计算实际用来对比的基准日期
          if (repeatInterval > 0 && repeatUnit) {
            // 重复事件：以今天的日期为基准，计算最近一次重复的日期
            var baseDate = calcNearestRepeatDate(ed, today, repeatInterval, repeatUnit);
            var diff = Math.floor((today - baseDate) / 86400000);
            if (diff >= 0) {
              item.is_anniversary = true;
              item.days_text = '已过去 ' + diff + ' 天';
              item.date_tag = '纪念日';
              item.repeat_label = repeatUnitMap[repeatUnit] + '重复';
            } else {
              item.is_anniversary = false;
              item.days_text = '还有 ' + Math.abs(diff) + ' 天';
              item.date_tag = '倒数日';
              item.repeat_label = repeatUnitMap[repeatUnit] + '重复';
            }
          } else {
            // 非重复事件：直接用事件日期计算
            var diff = Math.floor((today - ed) / 86400000);
            if (diff >= 0) {
              item.is_anniversary = true;
              item.days_text = '已过去 ' + diff + ' 天';
              item.date_tag = '纪念日';
            } else {
              item.is_anniversary = false;
              item.days_text = '还有 ' + Math.abs(diff) + ' 天';
              item.date_tag = '倒数日';
            }
          }
        } else {
          item.is_anniversary = true;
          item.days_text = '';
        }
        return item;
      });
      this.setData({ list: items });
    } catch (e) {
      this.setData({loadError:true});
      console.error(e);
      wx.showToast({ title: (e && (e.error || e.errMsg || e.message)) || '加载失败', icon: 'none' });
    }
    finally { this._pageLoading = false; this.setData({loading:false}); }
  },


  deleteTimeline: async function(e) {
    var id = e.currentTarget.dataset.id;
    wx.showModal({
      title: '确认删除',
      content: '确定要删除这条记录吗？',
      success: async function(res) {
        if (res.confirm) {
          try {
            await api.timelineDelete({ id: id });
            wx.showToast({ title: '已删除', icon: 'success' });
            // need to re-get this context
            var pages = getCurrentPages();
            var page = pages[pages.length - 1];
            page.loadData();
          } catch (err) {
            wx.showToast({ title: err.error || '删除失败', icon: 'none' });
          }
        }
      }
    });
  },  goToPublish: function() { wx.navigateTo({ url: '/pages/publish/publish?type=timeline' }); },

  goToDetail: function(e) {
    var id = e.currentTarget.dataset.id;
    if (id) {
      wx.navigateTo({ url: '/pages/timeline-detail/timeline-detail?id=' + id });
    }
  },

  goHome: function() { wx.redirectTo({ url: '/pages/index/index' }); },
  goBack: function() { wx.navigateBack(); },
  goProfile: function() { wx.redirectTo({ url: '/pages/profile/profile' }); }
});