<template>
  <div class="pdf">
    <div
      v-loading="!loadedRatio"
      class="show"
    >
      <pdf
        ref="pdf"
        :src="pdfSrc"
        :page="pageNum"
        :rotate="pageRotate"
        @password="password"
        @progress="loadedRatio = $event"
        @page-loaded="pageLoaded($event)"
        @num-pages="pageTotalNum = $event"
        @error="pdfError($event)"
        @link-clicked="page = $event"
      >
      </pdf>
    </div>

    <div class="pdf_footer">
      <div class="info">
        <div style="margin:0 auto;">当前页数/总页数：{{ pageNum }}/{{ pageTotalNum }}</div>
        <!-- <div>进度：{{ loadedRatio }}</div>
        <div>页面加载成功: {{ curPageNum }}</div> -->
      </div>
      <div class="operate">
        <!-- <div class="btn" @click.stop="clock">顺时针</div>
        <div class="btn" @click.stop="counterClock">逆时针</div> -->
        <div
          class="btn"
          @click.stop="prePage"
        >上一页</div>
        <div
          class="btn"
          @click.stop="nextPage"
        >下一页</div>
        <div
          class="btn"
          @click="scaleD"
        >放大</div>
        <div
          class="btn"
          @click="scaleX"
        >缩小</div>
        <!-- <div class="btn" @click="pdfPrint()">打印所有指定页</div>
        <div class="btn" @click="pdfPrintAll()">打印所有</div> -->
        <!-- <div class="btn" @click="logContent()">获取页面信息</div> -->
        <!-- <div class="btn" @click="fileDownload(pdfUrl, 'pdf文件')">下载</div> -->
      </div>
    </div>
  </div>
</template>

<script>
/* eslint-disable */
import pdf from "vue-pdf-signature"
import CMapReaderFactory from "vue-pdf-signature/src/CMapReaderFactory.js";

export default {
  name: "vue_pdf_preview",
  props: {
    // 当前pdf路径
    pdfUrl: {
      type: String,
      default: "",
    },
  },
  components: {
    pdf,
  },
  data () {
    return {
      // pdfSrcs: "/早期胃癌.pdf",
      pdfSrc: "",
      // 总页数
      pageTotalNum: 1,
      // 当前页数
      pageNum: 1,
      // 加载进度
      loadedRatio: 0,
      // 页面加载完成
      curPageNum: 0,
      // 放大系数 默认百分百
      scale: 100,
      // 旋转角度 ‘90’的倍数才有效
      pageRotate: 0,
      // 单击内部链接时触发 (目前我没有遇到使用场景)
      page: 0,
    }
  },
  watch: {},
  computed: {},
  created () {
  },
  mounted () {
  },
  methods: {
    loadPDF () {
      this.pdfSrc = pdf.createLoadingTask({
        url: this.pdfUrl,
        CMapReaderFactory
      });
    },
    //下载PDF
    fileDownload (data, fileName) {
      let blob = new Blob([data], {
        //type类型后端返回来的数据中会有，根据自己实际进行修改
        type: "application/pdf;charset-UTF-8",
      })
      let filename = fileName || "pdf.pdf"
      if (typeof window.navigator.msSaveBlob !== "undefined") {
        window.navigator.msSaveBlob(blob, filename)
      } else {
        var blobURL = window.URL.createObjectURL(blob)
        // 创建隐藏<a>标签进行下载
        var tempLink = document.createElement("a")
        tempLink.style.display = "none"
        tempLink.href = blobURL
        tempLink.setAttribute("download", filename)
        if (typeof tempLink.download === "undefined") {
          tempLink.setAttribute("target", "_blank")
        }
        document.body.appendChild(tempLink)
        tempLink.click()
        document.body.removeChild(tempLink)
        window.URL.revokeObjectURL(blobURL)
      }
    },

    //放大
    scaleD () {
      if (this.scale == 120) {
        return
      }
      this.scale += 5
      this.$refs.pdf.$el.style.width = parseInt(this.scale) + "%"
      this.$emit("scale", this.scale)
    },

    //缩小
    scaleX () {
      // scale 是百分百展示 不建议缩放
      if (this.scale == 85) {
        return
      }
      this.scale += -5
      // console.log(parseInt(this.scale) + "%")
      this.$refs.pdf.$el.style.width = parseInt(this.scale) + "%"
      this.$emit("scale", this.scale)
    },
    // 切换上一页
    prePage () {
      var p = this.pageNum
      p = p > 1 ? p - 1 : this.pageTotalNum
      this.pageNum = p
      document.querySelector(".pdf .show").scrollTop = 0
    },
    // 切换下一页
    nextPage () {
      var p = this.pageNum
      p = p < this.pageTotalNum ? p + 1 : 1
      this.pageNum = p
      document.querySelector(".pdf .show").scrollTop = 0
    },
    // 顺时针选中角度
    clock () {
      this.pageRotate += 90
    },
    // 逆时针旋转角度
    counterClock () {
      this.pageRotate -= 90
    },
    // pdf 有密码 则需要输入秘密
    password (updatePassword, reason) {
      updatePassword(prompt('password is "test"'))
      console.log("...reason...")
      console.log(reason)
      console.log("...reason...")
    },
    // 页面加载成功  当前页数
    pageLoaded (e) {
      this.$emit("current", e)
      this.curPageNum = e
      this.loadedRatio = 1
    },
    // 异常监听
    pdfError (error) {
      console.error(error)
    },
    // 打印所有
    pdfPrintAll () {
      this.$refs.pdf.print()
    },
    // 打印 第一页和第二页
    pdfPrint () {
      // 第一个参数 文档打印的分辨率
      // 第二个参数 文档打印的页数
      this.$refs.pdf.print(100, [1, 2])
    },
    // 获取当前页面pdf的文字信息内容
    logContent () {
      this.$refs.pdf.pdf.forEachPage(function (page) {
        return page.getTextContent().then(function (content) {
          let text = content.items.map((item) => item.str)
          let allStr = content.items.reduce(
            (initVal, item) => (initVal += item.str),
            ""
          )
          console.log(allStr) // 内容字符串
          console.log(text) // 内容数组
        })
      })
    },
  },
  beforeDestroy () {
    this.pdfSrc = null
  }
}
</script>

<style lang="scss" scoped>
.pdf {
  padding: 20px;
  .show {
    overflow: auto;
    margin: auto;
    // max-width: 790px;
    max-height: 660px;
  }
  .pdf_footer {
    position: sticky;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 10px 0;
    background-color: rgba(255, 255, 255, 1);
    .info {
      display: flex;
      flex-wrap: wrap;
      div {
        width: 30%;
      }
    }
    .operate {
      margin: 10px 0 0;
      display: flex;
      flex-wrap: wrap;
      div {
        // width: 80px;
        text-align: center;
        font-size: 15px;
      }
      .btn {
        cursor: pointer;
        margin: 5px 10px;
        width: 120px;
        border-radius: 10px;
        padding: 5px;
        color: #fff;
        background-color: #4e68ff;
      }
    }
  }
}
</style>
