<template>
  <div class="yearPicker" ref="yearPicker" :style="{ width: width + 'px' }">
    <div class="_inner labelText" :style="{ width: labelWidth + 'px' }">{{ labelText }}</div>
    <input class="_inner" ref="inputLeft" v-model.number="startShowYear" @focus="onFocus" type="text" @click="clickInput"
      name="yearInput" @input="checkStartInput($event)" placeholder="選擇年份" />
    <span>{{ sp }}</span>
    <input class="_inner" ref="inputRight" v-model.number="endShowYear" @focus="onFocus" type="text" @click="clickInput"
      name="yearInput" @input="checkEndInput($event)" placeholder="選擇年份" />
    <div class="_inner floatPanel" v-if="showPanel">
      <div class="_inner leftPanel">
        <div class="_inner panelHead">
          <i class="_inner el-icon-d-arrow-left" @click="onClickLeft"></i>
          {{ leftYearList[0] + "-" + leftYearList[9] }}
        </div>
        <div class="_inner panelContent">
          <div v-for="item in leftYearList" :class="{
            disabled: checkValidYear(item) != 0,
            oneSelected: item === startYear && oneSelected,
            startSelected: item === startYear,
            endSelected: item === endYear,
            _inner: true,
            betweenSelected: item > startYear && item < endYear
          }" :key="item">
            <a :class="{
              cell: true,
              _inner: true,
              selected: item === startYear || item === endYear
            }" @click="onClickItem(item)" @mouseover="onHoverItem(item)">
              {{ item }}
            </a>
          </div>
        </div>
      </div>
      <div class="_inner rightPanel">
        <div class="_inner panelHead">
          <i class="_inner el-icon-d-arrow-right" @click="onClickRight"></i>
          {{ rightYearList[0] + "-" + rightYearList[9] }}
        </div>
        <div class="_inner panelContent">
          <div :class="{
            disabled: checkValidYear(item) != 0,
            startSelected: item === startYear,
            endSelected: item === endYear,
            betweenSelected: item > startYear && item < endYear
          }" v-for="item in rightYearList" :key="item">
            <a :class="{
              cell: true,
              _inner: true,
              selected: item === endYear || item === startYear
            }" @click="onClickItem(item)" @mouseover="onHoverItem(item)">
              {{ item }}
            </a>
          </div>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
const SELECT_STATE = {
  unselect: 0, //未選擇
  selecting: 1, //選中一個(gè)
  selected: 2, //全部選中
};
export default {
  name: "YearPicker",
  computed: {
    oneSelected () {
      return (
        this.curState === SELECT_STATE.selecting && (this.startYear === this.endYear || this.endYear == null)
      );
    },
    startDate () {
      return this.startYear;
    },
    leftYearList () {
      return this.yearList.slice(0, 10);
    },
    rightYearList () {
      return this.yearList.slice(10, 20);
    }
  },
  props: {
    width: {
      default: 200,
    },
    labelWidth: {
      default: 80,
    },
    labelText: {
      default: "時(shí)間標(biāo)簽",
    },
    sp: {
      default: "至",
    },
    initYear: {
      default: null,
    },
  },
  data () {
    return {
      startShowYear: null,//輸入框 開始年份
      endShowYear: null,//輸入框 結(jié)束年份
      yearList: [], //選擇框里可選擇的年份
      showPanel: false, //選擇框是否顯示
      startYear: null, //選擇框選中的開始年份
      endYear: null, //選擇框選中的結(jié)束年份
      curYear: 0,
      curSelectedYear: 0,
      curState: SELECT_STATE.unselect,
    };
  },
  methods: {
    // 重置時(shí)間范圍
    onReset () {
      this.startYear = null;
      this.endYear = null;
      this.startShowYear = null;
      this.endShowYear = null;
      this.$emit("updateTimeRange", {
        startYear: null,
        endYear: null,
      });
    },
    // 檢查年份是否在可選區(qū)間內(nèi)  是否禁用
    checkValidYear (iYear) {
      if (this.initYear) {
        if (iYear > this.initYear.endYear) {
          return 1
        } else if (iYear < this.initYear.startYear) {
          return -1
        }
      }
      return 0
    },
    // 開始年份 輸入框校驗(yàn)  并將選擇框?qū)?yīng)開始年份選中
    checkStartInput (event) {
      if (isNaN(this.startShowYear)) {
        this.startShowYear = this.startYear;
      } else {
        this.startYear = this.startShowYear * 1;
      }
    },
    // 結(jié)束年份 輸入框校驗(yàn)  并將選擇框?qū)?yīng)結(jié)束年份選中
    checkEndInput () {
      if (isNaN(this.endShowYear)) {
        this.endShowYear = this.endYear;
      } else {
        this.endYear = this.endShowYear * 1;
      }
    },
    // 選擇框 鼠標(biāo)懸停事件  選中年份范圍
    onHoverItem (iYear) {
      if (this.checkValidYear(iYear) != 0) {
        return;
      }
      if (this.curState === SELECT_STATE.selecting) {
        let tmpStart = this.curSelectedYear;
        this.endYear = Math.max(tmpStart, iYear);
        this.startYear = Math.min(tmpStart, iYear);
      }
    },
    // 選擇框 點(diǎn)擊事件  選中年份范圍
    onClickItem (iYear) {
      if (this.checkValidYear(iYear) != 0) {
        // 點(diǎn)擊禁用年份  直接返回
        return;
      }
      if (this.curState === SELECT_STATE.unselect || this.curState === SELECT_STATE.selected) {
        // 點(diǎn)擊未選擇或全部選中狀態(tài)  開始年份直接選中當(dāng)前年份
        this.startYear = iYear;
        this.curSelectedYear = iYear;
        this.endYear = null;
        this.curState = SELECT_STATE.selecting;
      } else if (this.curState === SELECT_STATE.selecting) {
        // 處于選中一個(gè)，然后再點(diǎn)擊 
        // 如果 開始年份和結(jié)束年份是一樣  但 結(jié)束年份值為空 則 結(jié)束年份 == 開始年份
        if(this.startYear && !this.endYear){
          this.endYear = this.startYear;
        }
        this.endShowYear = this.endYear;
        this.startShowYear = this.startYear;
        this.curState = SELECT_STATE.selected;
        this.$emit("updateTimeRange", {
          startYear: this.startYear,
          endYear: this.endYear,
        });
        setTimeout(() => {
          //為動畫留的時(shí)間，可優(yōu)化
          this.showPanel = false;
        }, 300);
      }
    },
    //使 input 獲取焦點(diǎn)
    onFocus () {
      this.$nextTick(() => {
        this.showPanel = true;
        if(this.startShowYear && this.endShowYear){
          // 點(diǎn)擊選擇框  已選擇年份范圍  則將選擇框?qū)?yīng)年份選中
          this.endYear = this.endShowYear;
          this.startYear = this.startShowYear;
          this.curState = SELECT_STATE.selected;
        }
      });
    },
    // 點(diǎn)擊 input 阻止事件冒泡
    clickInput (e) {
      e.stopPropagation();
      return false;
    },
    // 點(diǎn)擊空白區(qū)域關(guān)閉選擇框
    closePanel (e) {
      if (!this.showPanel) {
        return;
      }
      if (typeof e.target.className !== "string" || e.target.className === "") {
        this.$nextTick(() => {
          this.changeYear();
          this.showPanel = false;
        });
        return;
      }
      if (
        e.target.className.indexOf("_inner") === -1 ||
        (e.target.name === "yearInput" &&
          e.target !== this.$refs.inputLeft &&
          e.target !== this.$refs.inputRight)
      ) {
        this.$nextTick(() => {
          this.changeYear();
          this.showPanel = false;
        });
      }

      e.stopPropagation();
      return false;
    },
    // 點(diǎn)擊空白區(qū)域關(guān)閉選擇框   時(shí)間檢驗(yàn)回顯
    changeYear () {
      if (!this.startYear || !this.endYear) {
        return;
      }
      if (this.startYear > this.endYear) {
        let tmp = this.endYear;
        this.endYear = this.startYear;
        this.startYear = tmp;
      }

      if (this.initYear) {
        this.startYear = Math.max(this.startYear, this.initYear.startYear)
        this.endYear = Math.min(this.endYear, this.initYear.endYear)
      }
      this.startShowYear = this.startYear;
      this.endShowYear = this.endYear;


      if (this.startYear && this.endYear) {
        this.$emit("updateTimeRange", {
          startYear: this.startYear,
          endYear: this.endYear + ""
        });
      } else {
        console.warn("WARN:年份不合法", this.startYear, this.endYear);
      }
    },
    // 點(diǎn)擊左箭頭  切換到上一個(gè)十年
    onClickLeft () {
      this.curYear = this.curYear * 1 - 10;
      this.updateYearList();
    },
    // 點(diǎn)擊右箭頭  切換到下一個(gè)十年
    onClickRight () {
      this.curYear = this.curYear * 1 + 10;
      this.updateYearList();
    },
    // 更新年份列表
    updateYearList () {
      let iStart = Math.floor(this.curYear / 10) * 10 - 10;
      iStart = iStart < 0 ? 0 : iStart;
      this.yearList = [];
      for (let index = 0; index < 20; index++) {
        this.yearList.push(iStart + index);
      }
    },
    //------------------對外接口------------------------
    // //直接傳時(shí)間戳
    // setYear(startYearStamp, endYearStamp) {
    //     if (!isNaN(startYearStamp) && !isNaN(endYearStamp)) {
    //         let startYear = moment(startYearStamp).format("yyyy");
    //         let endYear = moment(endYearStamp).format("yyyy");
    //         this.startYear = startYear * 1;
    //         this.endYear = endYear * 1;
    //         this.endShowYear = endYear * 1;
    //         this.startShowYear = startYear * 1;
    //     }
    // },
  },
  created () {
    this.curYear = new Date().getFullYear();
    this.updateYearList();
  },
  beforeUnmount () {
    // 組件銷毀時(shí)移除事件監(jiān)聽
    // 點(diǎn)擊空白區(qū)域關(guān)閉選擇框
    document.removeEventListener("click", this.closePanel.bind(this));
  },
  mounted () {
    // 組件掛載時(shí)添加事件監(jiān)聽
    // 點(diǎn)擊空白區(qū)域關(guān)閉選擇框
    document.addEventListener("click", this.closePanel.bind(this));
  },
};
</script>
<style lang="scss" scoped>
.yearPicker {
  font-size: 14px;
  display: flex;
  position: relative;
  transition: all 0.3s;

  input {
    text-align: center;
  }

  input:first-child {
    text-align: right;
  }

  background-color: #fff;

  .labelText {
    text-align: center;
  }

  span {
    padding: 0 8px;
    height: 38px;
    line-height: 38px;
  }

  border: 1px solid #eff1f3;
  height: 40px;
  line-height: 40px;
  border-radius: 4px;
  padding: 0 28px 0 8px;
  box-sizing: border-box;

  .floatPanel {
    >div {
      width: 50%;
    }

    padding: 0 16px;
    position: absolute;
    display: flex;
    background-color: #fff;
    z-index: 2000;
    border-radius: 4px;
    width: 650px;
    height: 250px;
    top: 40px;
    left: -10px;
    box-shadow: 0 2px 12px 0 rgba(0, 0, 0, 0.1);

    .panelContent {
      display: flex;
      flex-wrap: wrap;
      width: 100%;
      height: calc(100% - 70px);

      .disabled {
        color: #ccc;
      }

      .oneSelected {
        border-top-right-radius: 24px;
        border-bottom-right-radius: 24px;
      }

      .startSelected {
        background-color: #f6f6f7;
        border-top-left-radius: 24px;
        border-bottom-left-radius: 24px;
      }

      .endSelected {
        background-color: #f6f6f7;
        border-top-right-radius: 24px;
        border-bottom-right-radius: 24px;
      }

      .betweenSelected {
        background-color: #f6f6f7;
      }

      >div {
        width: 75px;
        height: 48px;
        line-height: 48px;
        margin: 3px 0;
        // border-radius: 24px;
        text-align: center;

        a {
          display: inline-block;
          width: 60px;
          height: 36px;
          cursor: pointer;
          line-height: 36px;
          border-radius: 18px;
        }

        .selected {
          background-color: #3e77fc;
          color: #fff;
        }
      }
    }

    .panelHead {
      position: relative;
      height: 46px;
      line-height: 46px;
      text-align: center;

      i {
        position: absolute;
        cursor: pointer;

        &:hover {
          color: #3e77fc;
        }
      }
    }

    .rightPanel {
      padding-left: 8px;
    }

    .leftPanel .panelHead i {
      left: 20px;
      top: 15px;
    }

    .rightPanel .panelHead i {
      right: 20px;
      top: 15px;
    }
  }

  .floatPanel::before {
    content: "";
    height: 100%;
    position: absolute;
    left: 50%;
    width: 1px;
    border-left: 1px solid #e4e4e4;
  }
}

input {
  width: 60px;
  border: none;
  height: 40px;
  line-height: 40px;
  box-sizing: border-box;
  background-color: transparent;
}

input:focus {
  outline: none;
  background-color: transparent;
}

.yearPicker:hover {
  border-color: #3e77fc;
}

.dateIcon {
  position: absolute;
  right: 16px;
  top: 9px;
  color: #adb2bc;
}
</style>

<template>
  <div class="moneyType">
   <div class="moneyType_con">
      <el-form :inline="true" :model="formInline" class="demo-form-inline">
        <el-form-item label="年度">
          <YearPicker ref="yearPicker" labelText="" :label-width="0"  :initYear="initYear" @updateTimeRange="updateStatisticYear"></YearPicker>
        </el-form-item>
        <el-form-item>
          <el-button type="primary" icon="el-icon-search" @click="getData(1)">查詢</el-button>
          <el-button type="success" icon="el-icon-refresh" @click="onReset(1)">重置</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>
<script>
import YearPicker from "../components/yearPicker.vue";
export default {
  components: {
    YearPicker
  },
  data () {
    return {
      initYear: {
        startYear: 1945,
        endYear: new Date().getFullYear()
      },//年份區(qū)間選擇框初始時(shí)間
      formInline: {
        nd: '',
        nds: '',
      },
    };
  },
  mounted () {
  },
  methods: {
    // 更新時(shí)間范圍
    updateStatisticYear({startYear, endYear}){
      this.formInline.nd = startYear
      this.formInline.nds = endYear
    },
    // 查詢
    getData () {
    },
    // 重置
    onReset () {
      this.formInline = {
        nd: '',
        nds: '',
      }
      this.$refs.yearPicker.onReset()
      this.getData();
    },
  },
};
</script>