feat(edit-docs): rewrite links to allow navigation in help

electron-docs-main.ts

@@ -9,6 +9,7 @@ import type { WriteStream } from "fs";
 import debounce from "./src/public/app/services/debounce.js";
 import { extractZip, initializeDatabase, startElectron } from "./electron-utils.js";
 import cls from "./src/services/cls.js";
+import type { AdvancedExportOptions } from "./src/services/export/zip.js";
 
 const NOTE_ID_USER_GUIDE = "pOsGYCXsbNQG";
 const markdownPath = path.join("docs", "User Guide");
@@ -69,7 +70,54 @@ async function exportData(format: "html" | "markdown", outputPath: string) {
 
         // First export as zip.
         const { exportToZipFile } = (await import("./src/services/export/zip.js")).default;
-        await exportToZipFile(NOTE_ID_USER_GUIDE, format, zipFilePath);
+
+        const exportOpts: AdvancedExportOptions = {};
+        if (format === "html") {
+            exportOpts.customRewriteLinks = (originalRewriteLinks, getNoteTargetUrl) => {
+                return (content: string, noteMeta: NoteMeta) => {
+                    content = content.replace(/src="[^"]*api\/images\/([a-zA-Z0-9_]+)\/[^"]*"/g, (match, targetNoteId) => {
+                        const url = getNoteTargetUrl(targetNoteId, noteMeta);
+
+                        return url ? `src="${url}"` : match;
+                    });
+
+                    content = content.replace(/src="[^"]*api\/attachments\/([a-zA-Z0-9_]+)\/image\/[^"]*"/g, (match, targetAttachmentId) => {
+                        const url = findAttachment(targetAttachmentId);
+
+                        return url ? `src="${url}"` : match;
+                    });
+
+                    content = content.replace(/href="[^"]*#root[^"]*attachmentId=([a-zA-Z0-9_]+)\/?"/g, (match, targetAttachmentId) => {
+                        const url = findAttachment(targetAttachmentId);
+
+                        return url ? `href="${url}"` : match;
+                    });
+
+                    content = content.replace(/href="[^"]*#root[a-zA-Z0-9_\/]*\/([a-zA-Z0-9_]+)[^"]*"/g, (match, targetNoteId) => {
+                        const components = match.split("/");
+                        components[components.length - 1] = `_help_${components[components.length - 1]}`;
+                        return components.join("/");
+                    });
+
+                    return content;
+
+                    function findAttachment(targetAttachmentId: string) {
+                        let url;
+
+                        const attachmentMeta = (noteMeta.attachments || []).find((attMeta) => attMeta.attachmentId === targetAttachmentId);
+                        if (attachmentMeta) {
+                            // easy job here, because attachment will be in the same directory as the note's data file.
+                            url = attachmentMeta.dataFileName;
+                        } else {
+                            console.info(`Could not find attachment meta object for attachmentId '${targetAttachmentId}'`);
+                        }
+                        return url;
+                    }
+                };
+            };
+        }
+
+        await exportToZipFile(NOTE_ID_USER_GUIDE, format, zipFilePath, exportOpts);
         await extractZip(zipFilePath, outputPath);
     } finally {
         if (await fsExtra.exists(zipFilePath)) {

src/services/export/zip.ts

@@ -23,7 +23,20 @@ import type { Response } from "express";
 import { RESOURCE_DIR } from "../resource_dir.js";
 import type { NoteMetaFile } from "../meta/note_meta.js";
 
-async function exportToZip(taskContext: TaskContext, branch: BBranch, format: "html" | "markdown", res: Response | fs.WriteStream, setHeaders = true) {
+type RewriteLinksFn = (content: string, noteMeta: NoteMeta) => string;
+
+export interface AdvancedExportOptions {
+    /**
+     * Provides a custom function to rewrite the links found in HTML or Markdown notes. This method is called for every note imported, if it's of the right type.
+     *
+     * @param originalRewriteLinks the original rewrite links function. Can be used to access the default behaviour without having to reimplement it.
+     * @param getNoteTargetUrl the method to obtain a note's target URL, used internally by `originalRewriteLinks` but can be used here as well.
+     * @returns a function to rewrite the links in HTML or Markdown notes.
+     */
+    customRewriteLinks?: (originalRewriteLinks: RewriteLinksFn, getNoteTargetUrl: (targetNoteId: string, sourceMeta: NoteMeta) => string | null) => RewriteLinksFn;
+}
+
+async function exportToZip(taskContext: TaskContext, branch: BBranch, format: "html" | "markdown", res: Response | fs.WriteStream, setHeaders = true, zipExportOptions?: AdvancedExportOptions) {
     if (!["html", "markdown"].includes(format)) {
         throw new ValidationError(`Only 'html' and 'markdown' allowed as export format, '${format}' given`);
     }
@@ -253,6 +266,8 @@ async function exportToZip(taskContext: TaskContext, branch: BBranch, format: "h
         return url;
     }
 
+    const rewriteFn = (zipExportOptions?.customRewriteLinks ? zipExportOptions?.customRewriteLinks(rewriteLinks, getNoteTargetUrl) : rewriteLinks);
+
     function rewriteLinks(content: string, noteMeta: NoteMeta): string {
         content = content.replace(/src="[^"]*api\/images\/([a-zA-Z0-9_]+)\/[^"]*"/g, (match, targetNoteId) => {
             const url = getNoteTargetUrl(targetNoteId, noteMeta);
@@ -297,8 +312,7 @@ async function exportToZip(taskContext: TaskContext, branch: BBranch, format: "h
     function prepareContent(title: string, content: string | Buffer, noteMeta: NoteMeta): string | Buffer {
         if (["html", "markdown"].includes(noteMeta?.format || "")) {
             content = content.toString();
-
+            content = rewriteFn(content, noteMeta);
-            content = rewriteLinks(content, noteMeta);
         }
 
         if (noteMeta.format === "html" && typeof content === "string") {
@@ -591,7 +605,7 @@ ${markdownContent}`;
     taskContext.taskSucceeded();
 }
 
-async function exportToZipFile(noteId: string, format: "markdown" | "html", zipFilePath: string) {
+async function exportToZipFile(noteId: string, format: "markdown" | "html", zipFilePath: string, zipExportOptions?: AdvancedExportOptions) {
     const fileOutputStream = fs.createWriteStream(zipFilePath);
     const taskContext = new TaskContext("no-progress-reporting");
 
@@ -601,7 +615,7 @@ async function exportToZipFile(noteId: string, format: "markdown" | "html", zipF
         throw new ValidationError(`Note ${noteId} not found.`);
     }
 
-    await exportToZip(taskContext, note.getParentBranches()[0], format, fileOutputStream, false);
+    await exportToZip(taskContext, note.getParentBranches()[0], format, fileOutputStream, false, zipExportOptions);
 
     log.info(`Exported '${noteId}' with format '${format}' to '${zipFilePath}'`);
 }