chore: improve pdf preview

packages/frontend/component/src/components/attachment-viewer/styles.css.ts

@@ -103,8 +103,22 @@ export const errorBtns = style({
   marginTop: '28px',
 });
 
-export const viewerPage = style({
+export const mainItemWrapper = style({
+  display: 'flex',
+  alignItems: 'center',
+  justifyContent: 'center',
   margin: '20px auto',
+  selectors: {
+    '&:first-of-type': {
+      marginTop: 0,
+    },
+    '&:last-of-type': {
+      marginBottom: 0,
+    },
+  },
+});
+
+export const viewerPage = style({
   maxWidth: 'calc(100% - 40px)',
   background: cssVarV2('layer/white'),
   boxSizing: 'border-box',
@@ -148,8 +162,11 @@ export const thumbnailsPages = style({
   },
 });
 
-export const thumbnailsPage = style({
+export const thumbnailsItemWrapper = style({
   margin: '0px 12px 12px',
+});
+
+export const thumbnailsPage = style({
   display: 'flex',
   overflow: 'clip',
   // width: '100%',

packages/frontend/component/src/components/attachment-viewer/titlebar.tsx

@@ -12,7 +12,7 @@ import { useState } from 'react';
 import { IconButton } from '../../ui/button';
 import { Menu, MenuItem } from '../../ui/menu';
 import * as styles from './styles.css';
-import { saveBufferToFile } from './utils';
+import { download } from './utils';
 
 const items = [
   {
@@ -23,11 +23,7 @@ const items = [
   {
     name: 'Download',
     icon: <LocalDataIcon />,
-    action(model: AttachmentBlockModel) {
-      const { sourceId, name } = model;
-      if (!sourceId) return;
-      saveBufferToFile(sourceId, name).catch(console.error);
-    },
+    action: download,
   },
 ];
 
@@ -65,7 +61,10 @@ export const Titlebar = ({
           <span>.{ext}</span>
         </div>
         <div>{size}</div>
-        <IconButton icon={<LocalDataIcon />}></IconButton>
+        <IconButton
+          icon={<LocalDataIcon />}
+          onClick={() => download(model)}
+        ></IconButton>
         <Menu
           items={<MenuItems model={model} />}
           rootOptions={{

packages/frontend/component/src/components/attachment-viewer/utils.ts

@@ -1,40 +1,63 @@
-import { fileTypeFromBuffer } from 'file-type';
+import type { AttachmentBlockModel } from '@blocksuite/affine/blocks';
 
-export async function saveBufferToFile(url: string, filename: string) {
-  // given input url may not have correct mime type
-  const blob = await attachmentUrlToBlob(url);
-  if (!blob) {
-    return;
+export async function getAttachmentBlob(model: AttachmentBlockModel) {
+  const sourceId = model.sourceId;
+  if (!sourceId) {
+    return null;
   }
 
-  const blobUrl = URL.createObjectURL(blob);
-  const a = document.createElement('a');
-  a.href = blobUrl;
-  a.download = filename;
-  document.body.append(a);
-  a.click();
-  a.remove();
-  URL.revokeObjectURL(blobUrl);
-}
-
-export async function attachmentUrlToBlob(
-  url: string
-): Promise<Blob | undefined> {
-  const buffer = await fetch(url).then(response => response.arrayBuffer());
+  const doc = model.doc;
+  let blob = await doc.blobSync.get(sourceId);
 
-  if (!buffer) {
-    console.warn('Could not get blob');
-    return;
+  if (blob) {
+    blob = new Blob([blob], { type: model.type });
   }
-  try {
-    const type = await fileTypeFromBuffer(buffer);
-    if (!type) {
+
+  return blob;
+}
+
+export function download(model: AttachmentBlockModel) {
+  (async () => {
+    const blob = await getAttachmentBlob(model);
+    if (!blob) {
       return;
     }
-    const blob = new Blob([buffer], { type: type.mime });
-    return blob;
-  } catch (error) {
-    console.error('Error converting attachment to blob', error);
-  }
-  return;
+
+    const blobUrl = URL.createObjectURL(blob);
+    const a = document.createElement('a');
+    a.href = blobUrl;
+    a.download = model.name;
+    document.body.append(a);
+    a.click();
+    a.remove();
+    URL.revokeObjectURL(blobUrl);
+  })().catch(console.error);
+}
+
+export function renderItem(
+  scroller: HTMLElement | null,
+  id: number,
+  imageBitmap: ImageBitmap
+) {
+  if (!scroller) return;
+
+  const wrapper = scroller.querySelector(`[data-index="${id}"]`);
+  if (!wrapper) return;
+
+  const item = wrapper.firstElementChild;
+  if (!item) return;
+  if (item.firstElementChild) return;
+
+  const canvas = document.createElement('canvas');
+  const ctx = canvas.getContext('bitmaprenderer');
+  if (!ctx) return;
+
+  canvas.width = imageBitmap.width;
+  canvas.height = imageBitmap.height;
+  canvas.style.width = '100%';
+  canvas.style.height = '100%';
+
+  ctx.transferFromImageBitmap(imageBitmap);
+
+  item.append(canvas);
 }