const { get } = require("../../utils/api");
const { refreshMe, requireLogin } = require("../../utils/auth");
const { isModuleEnabled, visibleModules } = require("../../utils/modules");
const { getActiveClassId, getActiveClassName, getEnabledModules, showError } = require("../../utils/page-helpers");

function formatDateTime(value) {
  if (!value) return "";
  return String(value).replace("T", " ").slice(0, 16);
}

function formatScheduleTime(item) {
  const start = formatDateTime(item.start_time);
  const end = formatDateTime(item.end_time);
  if (item.type === "deadline") return `截止 ${start}`;
  if (!end) return start;
  if (start.slice(0, 10) === end.slice(0, 10)) {
    return `${start} - ${end.slice(11)}`;
  }
  return `${start} - ${end}`;
}

function scheduleTypeText(type) {
  return {
    course: "课程",
    deadline: "截止日",
    activity: "活动"
  }[type] || type || "排期";
}

Page({
  data: {
    className: "HKU ICB",
    announcements: [],
    schedules: [],
    votes: [],
    timelines: [],
    quickModules: [],
    unreadCount: 0,
    loading: false
  },

  async onShow() {
    if (!requireLogin()) return;
    await this.load();
  },

  async load() {
    this.setData({ loading: true });
    try {
      await refreshMe();
      const app = getApp();
      const user = app.globalData.user;
      const classId = getActiveClassId();
      const enabledModules = getEnabledModules();
      const className = getActiveClassName();
      this.setData({
        className,
        quickModules: [
          ...visibleModules("class", enabledModules),
          ...visibleModules("interact", enabledModules)
        ].slice(0, 4)
      });

      const tasks = [get("/api/notifications/unread-count").catch(() => ({ unread_count: 0 }))];
      const names = ["unread"];
      if (isModuleEnabled("announcements", enabledModules)) {
        names.push("announcements");
        tasks.push(get("/api/announcements/", { page_size: 3, class_id: classId }));
      }
      if (isModuleEnabled("schedule", enabledModules)) {
        names.push("schedules");
        tasks.push(get("/api/schedule/upcoming", { limit: 3, class_id: classId }));
      }
      if (isModuleEnabled("votes", enabledModules)) {
        names.push("votes");
        tasks.push(get("/api/votes/", { page_size: 3, class_id: classId }));
      }
      if (isModuleEnabled("timeline", enabledModules)) {
        names.push("timelines");
        tasks.push(get("/api/timeline/", { page_size: 3, class_id: classId }));
      }

      const results = await Promise.all(tasks);
      const next = { announcements: [], schedules: [], votes: [], timelines: [] };
      names.forEach((name, index) => {
        const value = results[index];
        if (name === "unread") next.unreadCount = value.unread_count || 0;
        if (name === "announcements") next.announcements = value.items || [];
        if (name === "schedules") {
          next.schedules = (value || []).map((item) => ({
            ...item,
            schedule_time_text: formatScheduleTime(item),
            schedule_type_text: scheduleTypeText(item.type)
          }));
        }
        if (name === "votes") {
          next.votes = (value.items || []).map((item) => ({
            ...item,
            vote_type_text: item.vote_type === "multiple" ? "多选" : "单选",
            vote_action_text: item.has_voted ? "已参与" : "待参与"
          }));
        }
        if (name === "timelines") next.timelines = value.items || [];
      });
      this.setData(next);
    } catch (error) {
      showError(error);
    } finally {
      this.setData({ loading: false });
    }
  },

  openModule(event) {
    const key = event.currentTarget.dataset.key;
    wx.navigateTo({ url: `/pages/module/index?module=${key}` });
  },

  openSchedule(event) {
    wx.navigateTo({ url: `/pages/schedule-detail/index?id=${event.currentTarget.dataset.id}` });
  },

  openVote(event) {
    wx.navigateTo({ url: `/pages/vote-detail/index?id=${event.currentTarget.dataset.id}` });
  },

  openTimeline(event) {
    wx.navigateTo({ url: `/pages/timeline-detail/index?id=${event.currentTarget.dataset.id}` });
  }
});