3 files changed, 141 insertions, 0 deletions
diff --git a/app/assets/javascripts/pdf/assets/img/bg.gif b/app/assets/javascripts/pdf/assets/img/bg.gif
new file mode 100644
index 00000000000..c7e98e044f5
--- /dev/null
+++ b/app/assets/javascripts/pdf/assets/img/bg.gif
diff --git a/app/assets/javascripts/pdf/index.vue b/app/assets/javascripts/pdf/index.vue
new file mode 100644
index 00000000000..4603859d7b0
--- /dev/null
+++ b/app/assets/javascripts/pdf/index.vue
@@ -0,0 +1,73 @@
+<template>
+  <div class="pdf-viewer" v-if="hasPDF">
+    <page v-for="(page, index) in pages"
+      :key="index"
+      :v-if="!loading"
+      :page="page"
+      :number="index + 1" />
+  </div>
+</template>
+
+<script>
+  import pdfjsLib from 'pdfjs-dist';
+  import workerSrc from 'vendor/pdf.worker';
+
+  import page from './page/index.vue';
+
+  export default {
+    props: {
+      pdf: {
+        type: [String, Uint8Array],
+        required: true,
+      },
+    },
+    data() {
+      return {
+        loading: false,
+        pages: [],
+      };
+    },
+    components: { page },
+    watch: { pdf: 'load' },
+    computed: {
+      document() {
+        return typeof this.pdf === 'string' ? this.pdf : { data: this.pdf };
+      },
+      hasPDF() {
+        return this.pdf && this.pdf.length > 0;
+      },
+    },
+    methods: {
+      load() {
+        this.pages = [];
+        return pdfjsLib.getDocument(this.document)
+          .then(this.renderPages)
+          .then(() => this.$emit('pdflabload'))
+          .catch(error => this.$emit('pdflaberror', error))
+          .then(() => { this.loading = false; });
+      },
+      renderPages(pdf) {
+        const pagePromises = [];
+        this.loading = true;
+        for (let num = 1; num <= pdf.numPages; num += 1) {
+          pagePromises.push(
+            pdf.getPage(num).then(p => this.pages.push(p)),
+          );
+        }
+        return Promise.all(pagePromises);
+      },
+    },
+    mounted() {
+      pdfjsLib.PDFJS.workerSrc = workerSrc;
+      if (this.hasPDF) this.load();
+    },
+  };
+</script>
+
+<style>
+  .pdf-viewer {
+    background: url('./assets/img/bg.gif');
+    display: flex;
+    flex-flow: column nowrap;
+  }
+</style>
diff --git a/app/assets/javascripts/pdf/page/index.vue b/app/assets/javascripts/pdf/page/index.vue
new file mode 100644
index 00000000000..7b74ee4eb2e
--- /dev/null
+++ b/app/assets/javascripts/pdf/page/index.vue
@@ -0,0 +1,68 @@
+<template>
+  <canvas
+    class="pdf-page"
+    ref="canvas"
+    :data-page="number" />
+</template>
+
+<script>
+  export default {
+    props: {
+      page: {
+        type: Object,
+        required: true,
+      },
+      number: {
+        type: Number,
+        required: true,
+      },
+    },
+    data() {
+      return {
+        scale: 4,
+        rendering: false,
+      };
+    },
+    computed: {
+      viewport() {
+        return this.page.getViewport(this.scale);
+      },
+      context() {
+        return this.$refs.canvas.getContext('2d');
+      },
+      renderContext() {
+        return {
+          canvasContext: this.context,
+          viewport: this.viewport,
+        };
+      },
+    },
+    mounted() {
+      this.$refs.canvas.height = this.viewport.height;
+      this.$refs.canvas.width = this.viewport.width;
+      this.rendering = true;
+      this.page.render(this.renderContext)
+        .then(() => { this.rendering = false; })
+        .catch(error => this.$emit('pdflaberror', error));
+    },
+  };
+</script>
+
+<style>
+.pdf-page {
+  margin: 8px auto 0 auto;
+  border-top: 1px #ddd solid;
+  border-bottom: 1px #ddd solid;
+  width: 100%;
+}
+
+.pdf-page:first-child {
+  margin-top: 0px;
+  border-top: 0px;
+}
+
+.pdf-page:last-child {
+  margin-bottom: 0px;
+  border-bottom: 0px;
+}
+</style>