Add support for opening relative links to other PDFs

README.md

@@ -13,3 +13,19 @@ Most extensions currently in the marketplace have problems too deep to fix. Thes
 ## Support us
 
 If you find this extension helpful, please consider supporting its development through GitHub Sponsors. Your support helps maintain and improve this extension. Click [here](https://github.com/sponsors/jrandolf) to become a sponsor.
+
+
+## Updating PDF.js
+
+* update `pdfjs_version.txt` to target version and hash
+* from root folder of this repo run `tools/prepare_pdfjs.sh`, this will download PDF.js in given version and try to apply patches from the `patches` folder to it
+    * if the patches apply cleanly the command terminates and you are done
+    * if the patches fail to apply, for every conflict a `*.rej` file will be generated in the `assets/pdf.js` folder, 
+        you need to resolve these manually and then delete the `.rej` files
+
+If you want to keep current version of PDF.js but add some more patches, run with flag `--update-patches` which will stop after applying the current patches same as in the above case, leaving you to modify the `assets/pdf.js` however you see fit, 
+once done new patch will be created to match your edits.
+
+After you prepared your patches you can run the same command again, the second time the patches should apply cleanly and the `assets/pdf.js` should have the updated content you created earlier.
+
+The `prepare_pdfjs.sh` script does not create any commits in this repo, after you are happy with the patches you prepared be sure to commit everything manually.

assets/main.mjs

@@ -31,7 +31,11 @@ PDFViewerApplicationOptions.set("disablePreferences", true);
 
 void (async () => {
   await window.PDFViewerApplication.initializedPromise;
-  window.PDFViewerApplication.open(config);
+  await window.PDFViewerApplication.open(config);
+  const [,hash] = config.url.split("#")
+  if(hash){
+    PDFViewerApplication.pdfLinkService.setHash(decodeURIComponent(hash))
+  }
 })();
 
 window.addEventListener("message", async (event) => {

assets/pdf.js/web/viewer.mjs

@@ -13347,7 +13347,8 @@ const PDFViewerApplication = {
     const pdfRenderingQueue = new PDFRenderingQueue();
     pdfRenderingQueue.onIdle = this._cleanup.bind(this);
     this.pdfRenderingQueue = pdfRenderingQueue;
-    const pdfLinkService = new PDFLinkService({
+    const vscode = acquireVsCodeApi()
+    const pdfLinkService = new VSCodeLinkService(vscode, {
       eventBus,
       externalLinkTarget: AppOptions.get("externalLinkTarget"),
       externalLinkRel: AppOptions.get("externalLinkRel"),
@@ -15362,4 +15363,25 @@ var __webpack_exports__PDFViewerApplicationConstants = __webpack_exports__.PDFVi
 var __webpack_exports__PDFViewerApplicationOptions = __webpack_exports__.PDFViewerApplicationOptions;
 export { __webpack_exports__PDFViewerApplication as PDFViewerApplication, __webpack_exports__PDFViewerApplicationConstants as PDFViewerApplicationConstants, __webpack_exports__PDFViewerApplicationOptions as PDFViewerApplicationOptions };
 
-//# sourceMappingURL=viewer.mjs.map
+//# sourceMappingURL=viewer.mjs.map
+
+
+class VSCodeLinkService extends PDFLinkService {
+    #vscode
+    constructor(vscode, ...args){
+        super(...args)
+        this.#vscode = vscode
+    }
+
+    addLinkAttributes(link, url, newWindow = false){
+        if(typeof url === "string" && url.startsWith("https://file+.vscode-resource.vscode-cdn.net")){
+            link.onclick = () => {
+                this.#vscode.postMessage({
+                    open: url
+                });
+            };
+        } else {
+            return super.addLinkAttributes(link, url, newWindow)
+        }
+    }
+}

patches/pdf.js.patch

@@ -0,0 +1,43 @@
+diff --git a/web/viewer.mjs b/web/viewer.mjs
+index c3d794a..9df6c47 100644
+--- a/web/viewer.mjs
++++ b/web/viewer.mjs
+@@ -13347,7 +13347,8 @@ const PDFViewerApplication = {
+     const pdfRenderingQueue = new PDFRenderingQueue();
+     pdfRenderingQueue.onIdle = this._cleanup.bind(this);
+     this.pdfRenderingQueue = pdfRenderingQueue;
+-    const pdfLinkService = new PDFLinkService({
++    const vscode = acquireVsCodeApi()
++    const pdfLinkService = new VSCodeLinkService(vscode, {
+       eventBus,
+       externalLinkTarget: AppOptions.get("externalLinkTarget"),
+       externalLinkRel: AppOptions.get("externalLinkRel"),
+@@ -15362,4 +15363,25 @@ var __webpack_exports__PDFViewerApplicationConstants = __webpack_exports__.PDFVi
+ var __webpack_exports__PDFViewerApplicationOptions = __webpack_exports__.PDFViewerApplicationOptions;
+ export { __webpack_exports__PDFViewerApplication as PDFViewerApplication, __webpack_exports__PDFViewerApplicationConstants as PDFViewerApplicationConstants, __webpack_exports__PDFViewerApplicationOptions as PDFViewerApplicationOptions };
+
+-//# sourceMappingURL=viewer.mjs.map
+\ No newline at end of file
++//# sourceMappingURL=viewer.mjs.map
++
++
++class VSCodeLinkService extends PDFLinkService {
++    #vscode
++    constructor(vscode, ...args){
++        super(...args)
++        this.#vscode = vscode
++    }
++
++    addLinkAttributes(link, url, newWindow = false){
++        if(typeof url === "string" && url.startsWith("https://file+.vscode-resource.vscode-cdn.net")){
++            link.onclick = () => {
++                this.#vscode.postMessage({
++                    open: url
++                });
++            };
++        } else {
++            return super.addLinkAttributes(link, url, newWindow)
++        }
++    }
++}
+\ No newline at end of file

src/pdf_viewer_provider.ts

@@ -23,6 +23,7 @@ import {
   type Webview,
   type WebviewPanel,
   window,
+  commands,
 } from "vscode";
 
 import rawViewerHtml from "../assets/pdf.js/web/viewer.html";
@@ -45,6 +46,8 @@ const viewerHtml = rawViewerHtml
   .replace(/* html */ `<script src="viewer.mjs" type="module"></script>`, "")
   .replace(/* html */ `<link rel="stylesheet" href="viewer.css">`, "");
 
+const vscodeWebviewUriPrefix = "https://file+.vscode-resource.vscode-cdn.net"
+
 export class PDFViewerProvider implements CustomReadonlyEditorProvider {
   public static readonly viewType = "pdf.view";
 
@@ -111,6 +114,14 @@ export class PDFViewerProvider implements CustomReadonlyEditorProvider {
       document,
       webviewPanel.webview
     );
+
+    webviewPanel.webview.onDidReceiveMessage(msg => {
+        if("open" in msg){
+            const urlWithCdnScheme = msg.open as string
+            const [file, hash] = urlWithCdnScheme.substring(vscodeWebviewUriPrefix.length).split("#")
+            commands.executeCommand("vscode.open", Uri.file(file!).with({fragment: hash ?? ""}))
+        }
+    })
   }
 
   private getHtmlForWebview(document: PDFDocument, webview: Webview): string {
@@ -124,6 +135,7 @@ export class PDFViewerProvider implements CustomReadonlyEditorProvider {
 
     const settings = {
       url: `${webview.asWebviewUri(document.uri)}`,
+      docBaseUrl: `${webview.asWebviewUri(document.uri)}`,
     };
 
     return viewerHtml

tools/download_pdfjs.sh

@@ -24,6 +24,10 @@ fi
 
 # Unzip the file into the target directory
 unzip pdfjs.zip -d assets/pdf.js
+if [ "$?" != "0" ]; then
+    echo "Failed to unzip pdfjs.zip"
+    exit 1
+fi
 
 # Remove the zip file after extraction
 rm pdfjs.zip

tools/patching.sh

@@ -0,0 +1,50 @@
+#!/bin/bash
+
+# inspired by https://github.com/VSCodium/vscodium/blob/master/docs/howto-build.md#manual
+
+repo_root=$PWD
+patches=$repo_root/patches
+pdfjs=$repo_root/assets/pdf.js
+
+function prepare_patching {
+    pushd $pdfjs || { echo "'assets/pdf.js' dir not found"; exit 1; }
+
+    rm -rf $pdfjs/.git # use abs path to not accidentally nuke the main .git folder
+    git init --quiet
+    git add .
+    git commit -m start --quiet
+
+    popd
+}
+
+function clean_patching {
+    rm -rf $pdfjs/.git
+}
+
+function apply_patches {
+    pushd $pdfjs || { echo "'assets/pdf.js' dir not found"; exit 1; }
+
+    result=0
+    for p in $patches/*.patch; do
+        echo $p
+        if ! git apply --reject --recount --ignore-whitespace "${p}"; then
+        echo failed to apply patch "${p}"
+        result=1
+        fi
+    done
+
+    popd
+
+    return $result
+}
+
+function update_patches {
+    pushd $pdfjs || { echo "'assets/pdf.js' dir not found"; exit 1; }
+
+    git add .
+    mkdir -p $patches
+    git diff --cached > $patches/pdf.js.patch
+
+    popd
+}
+

tools/prepare_pdfjs.sh

@@ -0,0 +1,50 @@
+#!/bin/bash
+
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        --update-patches)
+        update_patches=true
+        shift
+        ;;
+    *)
+        echo "Unexpected argument: $1"
+        exit 1
+    esac
+done
+
+. tools/download_pdfjs.sh
+
+. tools/patching.sh
+
+prepare_patching
+trap "clean_patching" EXIT
+
+apply_patches
+apply_result=$?
+
+if [[ $apply_result -ne 0 ]]; then
+    echo
+    read -p "Patches did not apply cleanly, fix all conflicts (look for .rej files), then hit any key to continue..." -n1 -s
+    echo
+
+    leftover_rej=init
+    while [[ $leftover_rej ]]; do
+        leftover_rej=$(find assets/pdf.js -name '*.rej')
+        if [[ $leftover_rej ]]; then
+            echo
+            echo Some .rej files remained, makes sure to remove these after resolving the conflicts:
+            echo $leftover_rej
+
+            read -p "hit any key to continue after you resolved and removed all .rej files..." -n1 -s
+            echo
+        fi
+    done
+
+    update_patches
+elif [[  $update_patches ]]; then
+    echo
+    read -p "Do your changes inside 'assets/pdf.js', then hit any key to continue..." -n1 -s
+    echo
+
+    update_patches
+fi