const app = getApp();
const svc = require('../../services/exercise');

const DIM_MAP = {
  bodyPart: 'body-parts',
  equipment: 'equipment',
  target: 'targets',
  muscleGroup: 'muscle-groups',
  type: 'types'
};

const SECONDARY_LABEL = {
  bodyPart: '部位',
  equipment: '器械'
};

function labelForDim(d) {
  return ({
    bodyPart: '按部位',
    equipment: '按器械',
    target: '按目标',
    muscleGroup: '按肌群',
    type: '按类型'
  })[d] || '分类';
}

Page({
  data: {
    statusBarHeight: 20,
    dimension: 'bodyPart',
    title: '分类',
    dimTitle: '分类',
    // 主维度支持多选：activeValues 为已选 value 数组（空数组 = 全部）
    activeValues: [],
    values: [],
    // 二级维度（多维度筛选）：进入器械维度时交叉按部位，其余维度交叉按器械
    secondaryDim: 'equipment',
    secondaryKey: 'equipment',
    secondaryLabel: '器械',
    secondaryList: [],
    secondarySelected: [],
    exercises: [],
    loading: true,
    loadingMore: false,
    hasMore: true,
    page: 1,
    pageSize: 20,
    total: 0
  },

  onLoad(query) {
    const dimension = query.dimension || 'bodyPart';
    const value = query.value || '';
    const activeValues = value ? [value] : [];
    const secondaryDim = dimension === 'equipment' ? 'bodyPart' : 'equipment';
    const title = query.title || labelForDim(dimension);
    this.setData({
      statusBarHeight: app.globalData.statusBarHeight || 20,
      dimension,
      activeValues,
      dimTitle: labelForDim(dimension),
      secondaryDim,
      secondaryKey: DIM_MAP[secondaryDim] || 'equipment',
      secondaryLabel: SECONDARY_LABEL[secondaryDim] || '器械',
      title
    });
    this.loadValues();
  },

  loadValues() {
    this.setData({ loading: true });
    const key = DIM_MAP[this.data.dimension] || 'body-parts';
    const secKey = this.data.secondaryKey;
    Promise.all([
      svc.getCategories(key),
      svc.getCategories(secKey).catch(() => [])
    ]).then(([items, secItems]) => {
      const list = (items || []).slice();
      // 头部插入「全部」项：明确当前为「全部」
      list.unshift({ value: '', label: '全部' });
      // 用分类枚举里的干净中文标签回写标题，避免外部传入的标题出现乱码
      let title = this.data.title;
      const { activeValues } = this.data;
      if (activeValues.length === 1) {
        const hit = list.find((it) => it.value === activeValues[0]);
        if (hit && hit.label) title = hit.label;
      } else if (activeValues.length > 1) {
        title = `已选 ${activeValues.length} 个`;
      }
      // 主维度 items 带 active 标志（供 filter-bar 置顶/内联展示）
      const primaryItems = list.map((it) => ({ ...it, active: activeValues.includes(it.value) }));
      const secList = (secItems || []).slice().map((it) => ({
        ...it,
        active: this.data.secondarySelected.includes(it.value)
      }));
      this.setData({
        values: primaryItems,
        secondaryList: secList,
        title,
        loading: false
      });
      this.loadExercises();
    }).catch(() => {
      this.setData({ loading: false });
    });
  },

  buildParams(page) {
    const params = { page, pageSize: this.data.pageSize };
    const av = this.data.activeValues;
    if (av.length) params[this.data.dimension] = av.join(',');
    if (this.data.secondarySelected.length) {
      params[this.data.secondaryDim] = this.data.secondarySelected.join(',');
    }
    return params;
  },

  loadExercises() {
    this.setData({ loading: true, page: 1 });
    svc.listExercises(this.buildParams(1)).then((res) => {
      const items = (res && res.items) || [];
      const total = (res && res.total) || 0;
      this.setData({
        exercises: items,
        total,
        loading: false,
        hasMore: items.length < total
      });
    }).catch(() => {
      this.setData({ loading: false });
    });
  },

  onReachBottom() {
    if (this.data.loading || this.data.loadingMore || !this.data.hasMore) return;
    this.loadMore();
  },

  loadMore() {
    const next = this.data.page + 1;
    this.setData({ loadingMore: true });
    svc.listExercises(this.buildParams(next)).then((res) => {
      const items = (res && res.items) || [];
      const total = (res && res.total) || 0;
      const merged = this.data.exercises.concat(items);
      this.setData({
        exercises: merged,
        total,
        page: next,
        loadingMore: false,
        hasMore: merged.length < total
      });
    }).catch(() => {
      this.setData({ loadingMore: false });
    });
  },

  // 主维度（按器械/按部位）多选
  onPrimaryChange(e) {
    const vals = e.detail.values || [];
    const values = this.data.values.map((it) => ({ ...it, active: vals.includes(it.value) }));
    let title = this.data.title;
    if (vals.length === 1) {
      const hit = values.find((it) => it.value === vals[0]);
      title = (hit && hit.label) || labelForDim(this.data.dimension);
    } else if (vals.length > 1) {
      title = `已选 ${vals.length} 个`;
    } else {
      title = labelForDim(this.data.dimension);
    }
    this.setData({ activeValues: vals, values, title, page: 1 }, () => this.loadExercises());
  },

  // 二级维度（部位/器械）多选
  onSecondaryChange(e) {
    const values = e.detail.values || [];
    const secondaryList = this.data.secondaryList.map((it) => ({ ...it, active: values.includes(it.value) }));
    this.setData({ secondarySelected: values, secondaryList, page: 1 }, () => this.loadExercises());
  },

  onSecondaryClear() {
    const secondaryList = this.data.secondaryList.map((it) => ({ ...it, active: false }));
    this.setData({ secondarySelected: [], secondaryList, page: 1 }, () => this.loadExercises());
  },

  onExercise(e) {
    if (!e || !e.detail || !e.detail.id) return;
    wx.navigateTo({ url: '/pages/detail/detail?id=' + encodeURIComponent(e.detail.id) });
  }
});