Angularjavascript 手写日历的如何实现代码（不用插件）

<div class="plan_content_box" data-ng-init="showTime()">
    <div class="field" style="width: 100%;">
     <span class="field_label" style="width: 100%;text-align: center;">
      <select id="time_year" ng-change="change_year(select_year)" ng-model="select_year" ng-options="x.id as x.value for x in all_year">
       <!--<option value="1900">1900</option>-->
      </select> 年
      <select id="time_month" ng-change="change_month(select_month)" ng-model="select_month" ng-options="x.id as x.value for x in all_month">
 
      </select> 月 {{active_day}} 日
     </span>
    </div>
    
    <table class="table table-bordered hover_td" style="border: none;">
     <tr id="float_td">
      <td>星期日</td>
      <td>星期一</td>
      <td>星期二</td>
      <td>星期三</td>
      <td>星期四</td>
      <td>星期五</td>
      <td>星期六</td>
      <td ng-repeat="day in days track by $index" ng-click="change_day(day)"
        ng-class="{true:'active',false:''}[day==active_day]" ng-model="day">{{day}}</td>
     </tr>
    </table>
   </div>

 //  创建日历
  
  $scope.all_year = [];
  
  $scope.all_month = [];
  $scope.showTime = function() {
   //在select中填入年份
   for(var year = 2016; year < 2050; year++) {
    var obj_1 = {'value': year, 'id': year}
    $scope.all_year.push(obj_1);
   }
   
   //在select中填入月份
   for(var month = 1; month < 13; month++) {
    var obj_2 = {'value': month, 'id': month}
    $scope.all_month.push(obj_2);
   }
   console.log($scope.all_year)
   //初始化显示 当前年和月
   $scope.show_now()
   
   
  }
  //当select的选中的option发送变化的触发的事件
  $scope.change_year = function(data) {
   $scope.showDays(data, $scope.select_month)
  }
  $scope.change_month = function(data) {
   $scope.showDays($scope.select_year, data)
   
  }

  //返回指定的月份的天数 月份1-12
  $scope.calDays = function (year, month) {
   return new Date(year, month, 0).getDate();
  }

  $scope.days = [];
  //展示指定的年和月的所有日期
  $scope.showDays = function(year, month) {
   $scope.days = [];
   
   //得到表示指定年和月的1日的那个时间对象
   var date = new Date(year, month - 1, 1);
   
   
   //1.先添加响应的空白的li:这个月1号是星期几，就添加几个空白的li
   var dayOfWeek = date.getDay(); //得到1日是星期几
   for(var i = 0; i < dayOfWeek; i++) {
    $scope.days.push("");
   }
   
   
   //计算一个月有多少天
   var daysOfMonth = $scope.calDays(year, month);
   //2. 从1号开始添加li
   for(var i = 1; i <= daysOfMonth; i++) {
    $scope.days.push(i)
   }
  }
  
  $scope.active_day = ''
  $scope.select_year = ''
  $scope.select_month = ''
  //初始化显示 当前年和月
  $scope.show_now = function() {
   var now = new Date();
//   $("#time_year").val(now.getFullYear());
//   $("#time_month").val(now.getMonth() + 1); 
   $scope.active_day = now.getDate();
   $scope.select_year = now.getFullYear();
   $scope.select_month = now.getMonth() + 1;
   $scope.showDays($scope.select_year, $scope.select_month)
  }
  
  
  
  $scope.change_day = function(day){
   $scope.active_day = ""
   $scope.active_day = day
  }

  // 以上是创建日历