<template>
  <div class="tags-nav">
    <div class="close-con">
      <Dropdown transfer @on-click="handleTagsOption" style="margin-top:7px;">
        <Button size="small" type="text">
          <Icon :size="18" type="ios-close-circle-outline" />
        </Button>
        <DropdownMenu slot="list">
          <DropdownItem name="close-all">关闭所有</DropdownItem>
          <DropdownItem name="close-others">关闭其他</DropdownItem>
        </DropdownMenu>
      </Dropdown>
    </div>
    <ul v-show="visible" :style="{left: contextMenuLeft + 'px', top: contextMenuTop + 'px'}" class="contextmenu">
      <li v-for="(item, key) of menuList" @click="handleTagsOption(key)" :key="key">{{item}}</li>
    </ul>
    <div class="btn-con left-btn">
      <Button type="text" @click="handleScroll(240)">
        <Icon :size="18" type="ios-arrow-back" />
      </Button>
    </div>
    <div class="btn-con right-btn">
      <Button type="text" @click="handleScroll(-240)">
        <Icon :size="18" type="ios-arrow-forward" />
      </Button>
    </div>
    <div class="scroll-outer" ref="scrollOuter" @DOMMouseScroll="handlescroll" @mousewheel="handlescroll">
      <div ref="scrollBody" class="scroll-body" :style="{left: tagBodyLeft + 'px'}">
        <transition-group name="taglist-moving-animation">
          <Tag
            type="dot"
            v-for="(item, index) in list"
            ref="tagsPageOpened"
            :key="`tag-nav-${index}`"
            :name="item.name"
            :data-route-item="item"
            @on-close="handleClose(item)"
            @click.native="handleClick(item)"
            :closable="item.name !== $config.homeName"
            :color="isCurrentTag(item) ? 'primary' : 'default'"
            @contextmenu.prevent.native="contextMenu(item, $event)"
          >{{ showTitleInside(item) }}</Tag>
        </transition-group>
      </div>
    </div>
  </div>
</template>
<script lang="ts">
import { Component, Prop, Vue, Emit, Watch } from "vue-property-decorator";
import {beforeClose} from "../../libs/ui";
import { showTitle, routeEqual } from '../../libs/util'

@Component
export default class TagsNav extends Vue {
  tagBodyLeft : number = 0;
  rightOffset : number = 40;
  outerPadding : number = 4;
  contextMenuLeft : number = 0;
  contextMenuTop : number = 0;
  visible : boolean = false;
  menuList : object = {
    others: '关闭其他',
    all: '关闭所有'
  };
  refsTag : any ={};
  @Prop() private value! : {name:any,params:any,query:any};
  @Prop({type:Array,default:[]})   private list! : Array<any>;

  get currentRouteObj() : object{
    const { name , params , query} = this.value
     return { name, params, query }
  }

  handlescroll (e) {
      var type = e.type
      let delta = 0
      if (type === 'DOMMouseScroll' || type === 'mousewheel') {
        delta = (e.wheelDelta) ? e.wheelDelta : -(e.detail || 0) * 40
      }
      this.handleScroll(delta)
    }

     handleScroll (offset) {
      const outerWidth = (this.$refs.scrollOuter as any).offsetWidth
      const bodyWidth = (this.$refs.scrollBody as any).offsetWidth
      if (offset > 0) {
        this.tagBodyLeft = Math.min(0, this.tagBodyLeft + offset)
      } else {
        if (outerWidth < bodyWidth) {
          if (this.tagBodyLeft < -(bodyWidth - outerWidth)) {
            this.tagBodyLeft = this.tagBodyLeft
          } else {
            this.tagBodyLeft = Math.max(this.tagBodyLeft + offset, outerWidth - bodyWidth)
          }
        } else {
          this.tagBodyLeft = 0
        }
      }
    }

    handleTagsOption (type) {
      if (type.includes('all')) {
        // 关闭所有，除了home
        let res = this.list.filter(item => item.name === this.$config.homeName)
        this.emitClose(res, 'all',null);
      } else if (type.includes('others')) {
        // 关闭除当前页和home页的其他页
        let res = this.list.filter(item => routeEqual(this.currentRouteObj, item) || item.name === this.$config.homeName)
        this.emitClose(res, 'others', this.currentRouteObj)
        setTimeout(() => {
          this.getTagElementByRoute(this.currentRouteObj)
        }, 100)
      }
    }

    handleClose (current) {
      if (current.meta && current.meta.beforeCloseName && current.meta.beforeCloseName in beforeClose) {
        new Promise(beforeClose[current.meta.beforeCloseName]).then(close => {
          if (close) {
            this.close(current)
          }
        })
      } else {
        this.close(current)
      }
    }
    @Emit('on-close') emitClose(res,type ,route){}
    close (route) {
      let res = this.list.filter(item => !routeEqual(route, item))
      this.emitClose( res, undefined, route)
    }
    @Emit('input') emitInput(item){}
    handleClick (item) {
      this.emitInput(item)
    }
    showTitleInside (item) {
      return showTitle(item, this)
    }
    isCurrentTag (item) {
      return routeEqual(this.currentRouteObj, item)
    }
    moveToView (tag) {
      const outerWidth = (this.$refs.scrollOuter as any).offsetWidth
      const bodyWidth = (this.$refs.scrollBody as any).offsetWidth
      if (bodyWidth < outerWidth) {
        this.tagBodyLeft = 0
      } else if (tag.offsetLeft < -this.tagBodyLeft) {
        // 标签在可视区域左侧
        this.tagBodyLeft = -tag.offsetLeft + this.outerPadding
      } else if (tag.offsetLeft > -this.tagBodyLeft && tag.offsetLeft + tag.offsetWidth < -this.tagBodyLeft + outerWidth) {
        // 标签在可视区域
        this.tagBodyLeft = Math.min(0, outerWidth - tag.offsetWidth - tag.offsetLeft - this.outerPadding)
      } else {
        // 标签在可视区域右侧
        this.tagBodyLeft = -(tag.offsetLeft - (outerWidth - this.outerPadding - tag.offsetWidth))
      }
    }
    getTagElementByRoute (route) {
      this.$nextTick(() => {
        this.refsTag = this.$refs.tagsPageOpened
        this.refsTag.forEach((item, index) => {
          if (routeEqual(route, item.$attrs['data-route-item'])) {
            let tag = this.refsTag[index].$el
            this.moveToView(tag)
          }
        })
      })
    }
    contextMenu (item, e) {
      if (item.name === this.$config.homeName) {
        return
      }
      this.visible = true
      const offsetLeft = this.$el.getBoundingClientRect().left
      this.contextMenuLeft = e.clientX - offsetLeft + 10
      this.contextMenuTop = e.clientY - 64
    }
    closeMenu () {
      this.visible = false
    }

    mounted () {
      setTimeout(() => {
        this.getTagElementByRoute(this.$route)
      }, 200)
    }

    @Watch('$route') 
    routeChange(to){
      this.getTagElementByRoute(to)
    }
    @Watch('visible') 
    visibleChange(value){
      if (value) {
        document.body.addEventListener('click', this.closeMenu)
      } else {
        document.body.removeEventListener('click', this.closeMenu)
      }
    }
}
</script>
