<template>
 <nav>
  <ul class="pagination">
   <li :class="{'disabled': current == 1}"><a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" @click="setCurrent(current - 1)"> « </a></li>
   <li :class="{'disabled': current == 1}"><a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" @click="setCurrent(1)"> 首页 </a></li>
   <li v-for="p in grouplist" :class="{'active': current == p.val}"><a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" 
                                     @click="setCurrent(p.val)"> {{ p.text }} </a>
   </li>
   <li :class="{'disabled': current == page}"><a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" @click="setCurrent(page)"> 尾页 </a></li>
   <li :class="{'disabled': current == page}"><a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" @click="setCurrent(current + 1)"> »</a></li>
  </ul>
 </nav>
</template>
<script type="es6">
 export default{
  data(){
   return {
    current: this.currentPage
   }
  },
  props: {
   total: {// 数据总条数
    type: Number,
    default: 0
   },
   display: {// 每页显示条数
    type: Number,
    default: 10
   },
   currentPage: {// 当前页码
    type: Number,
    default: 1
   },
   pagegroup: {// 分页条数
    type: Number,
    default: 5,
    coerce: function (v) {
     v = v > 0 ? v : 5;
     return v % 2 === 1 ? v : v + 1;
    }
   }
  },
  computed: {
   page: function () { // 总页数
    return Math.ceil(this.total / this.display);
   },
   grouplist: function () { // 获取分页页码
    var len = this.page, temp = [], list = [], count = Math.floor(this.pagegroup / 2), center = this.current;
    if (len <= this.pagegroup) {
     while (len--) {
      temp.push({text: this.page - len, val: this.page - len});
     }
     ;
     return temp;
    }
    while (len--) {
     temp.push(this.page - len);
    }
    ;
    var idx = temp.indexOf(center);
    (idx < count) && ( center = center + count - idx);
    (this.current > this.page - count) && ( center = this.page - count);
    temp = temp.splice(center - count - 1, this.pagegroup);
    do {
     var t = temp.shift();
     list.push({
      text: t,
      val: t
     });
    } while (temp.length);
    if (this.page > this.pagegroup) {
     (this.current > count + 1) && list.unshift({text: '...', val: list[0].val - 1});
     (this.current < this.page - count) && list.push({text: '...', val: list[list.length - 1].val + 1});
    }
    return list;
   }
  },
  methods: {
   setCurrent: function (idx) {
    if (this.current != idx && idx > 0 && idx < this.page + 1) {
     this.current = idx;
     this.$emit('pagechange', this.current);
    }
   }
  }
 }
</script>
<style lang="less">
 .pagination {
  overflow: hidden;
  display: table;
  margin: 0 auto;
  /*width: 100%;*/
  height: 50px;
 li {
  float: left;
  height: 30px;
  border-radius: 5px;
  margin: 3px;
  color: #666;
 &
 :hover {
  background: #000;
 a {
  color: #fff;
 }
 }
 a {
  display: block;
  width: 30px;
  height: 30px;
  text-align: center;
  line-height: 30px;
  font-size: 12px;
  border-radius: 5px;
  text-decoration: none
 }
 }
 .active {
  background: #000;
 a {
  color: #fff;
 }
 }
 }
</style>