// pages/rollCall/rollCall.js
const db = wx.cloud.database();
Page({
  data: {
    students: [],
    currentStudent: null,
    score: '',
    effects: [
      { name: '+0分', value: 0, type: 'add' },
      { name: '+1分', value: 1, type: 'add' },
      { name: '+2分', value: 2, type: 'add' },
      { name: '+3分', value: 3, type: 'add' },
      { name: '+4分', value: 4, type: 'add' },
      { name: '+5分', value: 5, type: 'add' },
      { name: '-1分', value: -1, type: 'add' },
      { name: '-2分', value: -2, type: 'add' },
      { name: '积分乘2', value: 2, type: 'multiply' },
      { name: '积分除2', value: 0.5, type: 'divide' }
    ],
    page: 1,
    pageSize: 10,
    hasMore: true
  },
  
  loadAllStudents: function() {
    const that = this;
    const loadNextPage = function() {
      const studentsCollection = db.collection('users');
      studentsCollection.skip((that.data.page - 1) * that.data.pageSize).limit(that.data.pageSize).get({
        success: res => {
          if (res.data.length === 0) {
            that.setData({
              hasMore: false
            });
            return;
          }
          let newStudents = that.data.students.concat(res.data);
          that.setData({
            students: newStudents,
            page: that.data.page + 1
          });
          // 如果还有更多数据，继续加载下一页
          if (that.data.hasMore) {
            loadNextPage();
          }
        },
        fail: err => {
          console.error('学生数据加载失败：', err);
        }
      });
    };
    loadNextPage();
  },
  
  onLoad: function() {
    this.loadAllStudents();
  },
  
  // 按积分加权随机点名
  weightedRandomRollCall: function() {
    const students = this.data.students;
    if (students.length === 0) {
      wx.showToast({
        title: '没有可点名的学生',
        icon: 'none',
        duration: 2000
      });
      return;
    }

    const weights = students.map(student => 1 / (student.score + 1));
    const totalWeight = weights.reduce((sum, weight) => sum + weight, 0);
    const randomWeight = Math.random() * totalWeight;
    let cumulativeWeight = 0;
    let selectedStudent = null;

    for (let i = 0; i < weights.length; i++) {
      cumulativeWeight += weights[i];
      if (cumulativeWeight >= randomWeight) {
        selectedStudent = students[i];
        break;
      }
    }

    if (selectedStudent) {
      this.setData({
        currentStudent: selectedStudent
      });
      console.log(this.data.currentStudent)
      wx.showToast({
        title: `点到：${selectedStudent.name}`,
        icon: 'none',
        duration: 2000
      });
    } else {
      wx.showToast({
        title: '未抽到学生',
        icon: 'none',
        duration: 2000
      });
    }
  },
  
  // 用户输入分数
  inputScore: function(e) {
    this.setData({
      score: e.detail.value
    });
  },

  // 更新分数
  updatescore: function() {
    let db = wx.cloud.database()
    let userCollection = db.collection('users')
    const xuehao = this.data.currentStudent.num;
    const inputScore = this.data.score;
    if (!xuehao || inputScore === '') {
      wx.showToast({
        title: '信息不完整',
        icon: 'none',
        duration: 2000
      });
      return;
    }
    const newScore = parseFloat(this.data.currentStudent.score) + parseFloat(inputScore);
    userCollection.where({
      num: xuehao
    }).update({
      data: {
        score: newScore
      }
    }).then(res => {
      console.log('更新成功');
      wx.showToast({
        title: '分数更新成功',
        icon: 'success',
        duration: 2000
      });
    }).catch(err => {
      console.log('更新失败', err); 
    })
  },
  addHalfScore: function() {
    if (this.data.currentStudent) {
      this.updateStudentScore(0.5);
    } else {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
    }
  },
  addoneScore: function() {
    if (this.data.currentStudent) {
      this.updateStudentScore(1);
    } else {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
    }
  },
  addoneandhalfScore: function() {
    if (this.data.currentStudent) {
      this.updateStudentScore(1.5);
    } else {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
    }
  },
  addtwoScore: function() {
    if (this.data.currentStudent) {
      this.updateStudentScore(2);
    } else {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
    }
  },
  addtwoandhalfScore: function() {
    if (this.data.currentStudent) {
      this.updateStudentScore(2.5);
    } else {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
    }
  },
  addthreeScore: function() {
    if (this.data.currentStudent) {
      this.updateStudentScore(3);
    } else {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
    }
  },

  
  subtractOneScore: function() {
    if (this.data.currentStudent) {
      this.updateStudentScore(-1);
    } else {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
    }
  },

  // 更新选中学生的分数
  updateStudentScore: function(amount) {
    const newScore = parseFloat(this.data.currentStudent.score) + amount;
    const studentId = this.data.currentStudent._id;
    const userCollection = db.collection('users');
    userCollection.doc(studentId).update({
      data: {
        score: newScore
      }
    }).then(res => {
      console.log('分数更新成功');
      wx.showToast({
        title: '分数更新成功',
        icon: 'success',
        duration: 2000
      });
      this.setData({
        currentStudent: {...this.data.currentStudent, score: newScore.toString()}
      });
    }).catch(err => {
      console.error('分数更新失败', err);
      wx.showToast({
        title: '分数更新失败',
        icon: 'none',
        duration: 2000
      });
    });
  },
  applyEffect: function() {
    if (!this.data.currentStudent) {
      wx.showToast({
        title: '请先随机点名一个学生',
        icon: 'none',
        duration: 2000
      });
      return;
    }
  
    
    const effect = this.data.effects[Math.floor(Math.random() * this.data.effects.length)];
    this.setData({
      effect: effect 
    });
  
    
    let newScore;
    switch (effect.type) {
      case 'add':
        newScore = parseFloat(this.data.currentStudent.score) + effect.value;
        break;
      case 'multiply':
        newScore = parseFloat(this.data.currentStudent.score) * effect.value;
        break;
      case 'divide':
        if (this.data.currentStudent.score === 0) {
          wx.showToast({
            title: '分数不能为0',
            icon: 'none',
            duration: 2000
          });
          return;
        }
        newScore = parseFloat(this.data.currentStudent.score) * effect.value;
        break;
      default:
        newScore = this.data.currentStudent.score;
    }
  
    const studentId = this.data.currentStudent._id;
    const userCollection = db.collection('users');
    userCollection.doc(studentId).update({
      data: {
        score: newScore
      }
    }).then(res => {
      console.log('分数更新成功');
      wx.showToast({
        title: `应用效果：${effect.name}`,
        icon: 'success',
        duration: 2000
      });
      this.setData({
        currentStudent: {...this.data.currentStudent, score: newScore.toString()}
      });
    }).catch(err => {
      console.error('分数更新失败', err);
      wx.showToast({
        title: '分数更新失败',
        icon: 'none',
        duration: 2000
      });
    });
  },
  //刷新
  refreshData: function() {
    this.loadStudents1();
  },
  
  // 加载学生数据
  loadStudents1: function() {
    const studentsCollection = db.collection('users');
    studentsCollection.get({
      success: res => {
        if (res.data.length === 0) {
          wx.showToast({
            title: '没有学生数据',
            icon: 'none',
            duration: 2000
          });
          return;
        }
        this.setData({
          students: res.data,
          currentStudent: null, 
          effect: null 
        });
      },
      fail: err => {
        console.error('学生数据加载失败：', err);
      }
    });
  },
  goBack: function() {
    wx.navigateTo({
      url: '/pages/teacherHomePage/teacherHomePage' 
    });
  }
});