Enable annotation deletion

README.md

@@ -332,10 +332,7 @@ It is used by countless Obsidian plugins and has been helping the community as a
 He's also the author of several popular Obsidian plugins including Tag Wrangler.
 
 PDF++ offers two ways to highlight text in PDF: one that does not involve modifying the PDF file, and the other that writes highlight annotations directly into the PDF file.
-The latter is powered by the following libraries:
-
-- pdf-lib: A JavaScript library for creating and modifying PDF documents. The [original project](https://github.com/Hopding/pdf-lib) was created by Andrew Dillon. PDF++ uses a [forked version](https://github.com/cantoo-scribe/pdf-lib) maintained by Cantoo Scribe.
-- [pdfAnnotate](https://github.com/highkite/pdfAnnotate): A JavaScript library for creating PDF annotations by Thomas Osterland.
+The latter is powered by the pdf-lib, a JavaScript library for creating and modifying PDF documents. The [original project](https://github.com/Hopding/pdf-lib) was created by Andrew Dillon. PDF++ uses a [forked version](https://github.com/cantoo-scribe/pdf-lib) maintained by Cantoo Scribe.
 
 ## Compatibility
 

package.json

@@ -15,7 +15,6 @@
         "@types/node": "^16.11.6",
         "@typescript-eslint/eslint-plugin": "5.29.0",
         "@typescript-eslint/parser": "5.29.0",
-        "annotpdf": "^1.0.15",
         "builtin-modules": "3.3.0",
         "esbuild": "0.17.3",
         "monkey-around": "^2.3.0",
@@ -24,4 +23,4 @@
         "tslib": "2.4.0",
         "typescript": "4.7.4"
     }
-}
+}

src/annotation-modals.ts

@@ -0,0 +1,87 @@
+import { PDFPlusAPI } from 'api';
+import PDFPlus from 'main';
+import { Component, Modal, Setting, TFile } from 'obsidian';
+
+
+class PDFPlusModal extends Modal {
+    plugin: PDFPlus;
+    api: PDFPlusAPI;
+    component: Component;
+
+    constructor(plugin: PDFPlus) {
+        super(plugin.app);
+        this.plugin = plugin;
+        this.api = plugin.api;
+        this.component = new Component();
+    }
+
+    onOpen() {
+        this.component.load();
+        this.contentEl.empty();
+    }
+
+    onClose() {
+        this.contentEl.empty();
+        this.component.unload();
+    }
+}
+
+class PDFAnnotationModal extends PDFPlusModal {
+    file: TFile;
+    page: number;
+    id: string;
+
+    constructor(plugin: PDFPlus, file: TFile, page: number, id: string) {
+        super(plugin);
+        this.file = file;
+        this.page = page;
+        this.id = id;
+    }
+}
+
+export class PDFAnnotationEditModal extends PDFAnnotationModal { }
+
+export class PDFAnnotationDeleteModal extends PDFAnnotationModal {
+    onOpen() {
+        super.onOpen();
+
+        this.contentEl.createEl('h3', { text: `${this.plugin.manifest.name}: delete annotation` });
+        this.contentEl.createEl('p', { text: 'Are you sure you want to delete this annotation?' });
+        this.contentEl.createEl('p', { cls: 'mod-warning', text: 'There are one or more links pointing to this annotation.' });
+
+        new Setting(this.contentEl)
+            .addButton((button) => {
+                button
+                    .setButtonText('Delete')
+                    .setWarning()
+                    .onClick(() => {
+                        this.deleteAnnotation();
+                        this.close();
+                    });
+            })
+            .addButton((button) => {
+                button
+                    .setButtonText('Cancel')
+                    .onClick(() => this.close());
+            })
+            .then((setting) => setting.setClass('no-border'));
+    }
+
+    openIfNeccessary() {
+        if (this.shouldOpen()) {
+            return this.open();
+        }
+        return this.deleteAnnotation();
+    }
+
+    shouldOpen() {
+        return this.plugin.settings.warnBacklinkedAnnotationDelete
+            && this.api.isBacklinked(this.file, {
+                page: this.page, annotation: this.id
+            });
+    }
+
+    deleteAnnotation() {
+        this.api.highlight.writeFile.deleteAnnotation(this.file, this.page, this.id);
+    }
+}

src/api/copy-link.ts

@@ -126,6 +126,7 @@ export class copyLinkAPI extends PDFPlusAPISubmodule {
                         pageLabel: pageView.pageLabel ?? ('' + page),
                         pageCount: child.pdfViewer.pagesCount,
                         text,
+                        colorName: '',
                         ...this.getLinkTemplateVariables(child, child.file!, `#page=${page}&annotation=${id}`, page)
                     });
 

src/api/highlights/write-file/index.ts

@@ -1,21 +1,28 @@
+import { PDFRef } from '@cantoo/pdf-lib';
 import { Notice, TFile } from 'obsidian';
 
 import PDFPlus from 'main';
-import { PdfAnnotateIO } from './pdfAnnotate';
+// import { PdfAnnotateIO } from './pdfAnnotate';
 import { PdfLibIO } from './pdf-lib';
 import { PDFPlusAPISubmodule } from 'api/submodule';
-import { parsePDFSubpath } from 'utils';
+import { formatAnnotationID, parsePDFSubpath } from 'utils';
 import { PDFViewerChild, Rect } from 'typings';
 
 
 export class AnnotationWriteFileAPI extends PDFPlusAPISubmodule {
     pdflib: PdfLibIO;
-    pdfAnnotate: PdfAnnotateIO;
+    // pdfAnnotate: PdfAnnotateIO;
 
     constructor(plugin: PDFPlus) {
         super(plugin);
         this.pdflib = new PdfLibIO(plugin);
-        this.pdfAnnotate = new PdfAnnotateIO(plugin);
+        // this.pdfAnnotate = new PdfAnnotateIO(plugin);
+    }
+
+    private getPdfIo(): IPdfIo {
+        // if (this.plugin.settings.writeFileLibrary === 'pdfAnnotate') return this.pdfAnnotate;
+        // else 
+        return this.pdflib;
     }
 
     async highlightSelection(colorName?: string) {
@@ -58,9 +65,16 @@ export class AnnotationWriteFileAPI extends PDFPlusAPISubmodule {
         }
     }
 
-    getPdfIo(): IPdfIo {
-        if (this.plugin.settings.writeFileLibrary === 'pdfAnnotate') return this.pdfAnnotate;
-        else return this.pdflib;
+    deleteAnnotation(file: TFile, pageNumber: number, id: string) {
+        const io = this.pdflib;
+        io.process(file, (pdfDoc) => {
+            const page = pdfDoc.getPage(pageNumber - 1);
+            const ref = page.node.Annots()?.asArray().find((ref): ref is PDFRef => {
+                return ref instanceof PDFRef
+                    && formatAnnotationID(ref.objectNumber, ref.generationNumber) === id;
+            });
+            if (ref) page.node.removeAnnot(ref);
+        });
     }
 }
 

src/api/highlights/write-file/pdf-lib.ts

@@ -1,9 +1,8 @@
 import { TFile } from 'obsidian';
 import { PDFDocument, PDFPage, PDFRef, PDFString } from '@cantoo/pdf-lib';
-import { Util } from 'annotpdf';
 
 import { PDFPlusAPISubmodule } from 'api/submodule';
-import { formatAnnotationID, getBorderRadius } from 'utils';
+import { convertDateToPDFDate, formatAnnotationID, getBorderRadius } from 'utils';
 import { Rect } from 'typings';
 import { IPdfIo } from '.';
 
@@ -31,7 +30,7 @@ export class PdfLibIO extends PDFPlusAPISubmodule implements IPdfIo {
                 // For Contents & T, make sure to pass a PDFString, not a raw string!!
                 // https://github.com/Hopding/pdf-lib/issues/555#issuecomment-670243166
                 Contents: PDFString.of(contents ?? ''),
-                M: PDFString.of(Util.convertDateToPDFDate(new Date())),
+                M: PDFString.of(convertDateToPDFDate(new Date())),
                 T: PDFString.of(this.plugin.settings.author),
                 CA: this.plugin.settings.writeHighlightToFileOpacity,
                 Border: [borderRadius, borderRadius, 0],

src/api/index.ts

@@ -1,12 +1,12 @@
-import { App, Component, TFile } from 'obsidian';
+import { App, Component, TFile, parseLinktext } from 'obsidian';
 import { PDFDocumentProxy } from 'pdfjs-dist';
 
 import PDFPlus from 'main';
 import { ColorPalette } from 'color-palette';
 import { copyLinkAPI } from './copy-link';
 import { HighlightAPI } from './highlights';
 import { WorkspaceAPI } from './workspace-api';
-import { encodeLinktext } from 'utils';
+import { encodeLinktext, parsePDFSubpath } from 'utils';
 import { AnnotationElement, EventBus, ObsidianViewer, PDFPageView, PDFViewerChild } from 'typings';
 
 
@@ -132,10 +132,10 @@ export class PDFPlusAPI {
     }
 
     getPDFViewerChildAssociatedWithNode(node: Node) {
-		for (const [viewerEl, child] of this.plugin.pdfViwerChildren) {
-			if (viewerEl.contains(node)) return child;
-		}
-	}
+        for (const [viewerEl, child] of this.plugin.pdfViwerChildren) {
+            if (viewerEl.contains(node)) return child;
+        }
+    }
 
     async destIdToSubpath(destId: string, doc: PDFDocumentProxy) {
         const dest = await doc.getDestination(destId);
@@ -232,4 +232,52 @@ export class PDFPlusAPI {
 
         return 'md' !== file.extension ? '!' + nonEmbedLink : nonEmbedLink;
     }
+
+    isBacklinked(file: TFile, subpathParams?: { page: number, selection?: [number, number, number, number], annotation?: string }): boolean {
+        // validate parameters
+        if (subpathParams) {
+            const { page, selection, annotation } = subpathParams;
+            if (isNaN(page) || page < 1) throw new Error('Invalid page number');
+            if (selection && (selection.length !== 4 || selection.some((pos) => isNaN(pos)))) throw new Error('Invalid selection');
+            if (selection && typeof annotation === 'string') throw new Error('Selection and annotation cannot be used together');
+        }
+
+        // query type
+        const isFileQuery = !subpathParams;
+        const isPageQuery = subpathParams && !subpathParams.selection && !subpathParams.annotation;
+        const isSelectionQuery = subpathParams && !!(subpathParams.selection);
+        const isAnnotationQuery = typeof subpathParams?.annotation === 'string';
+
+        const backlinkDict = this.app.metadataCache.getBacklinksForFile(file);
+
+        if (isFileQuery) return backlinkDict.count() > 0;
+
+        for (const sourcePath of backlinkDict.keys()) {
+            const backlinks = backlinkDict.get(sourcePath);
+            if (!backlinks) continue;
+
+            for (const backlink of backlinks) {
+                const { subpath } = parseLinktext(backlink.link);
+                const result = parsePDFSubpath(subpath);
+                if (!result) continue;
+
+                if (isPageQuery && result.page === subpathParams.page) return true;
+                if (isSelectionQuery
+                    && 'beginIndex' in result
+                    && result.page === subpathParams.page
+                    && result.beginIndex === subpathParams.selection![0]
+                    && result.beginOffset === subpathParams.selection![1]
+                    && result.endIndex === subpathParams.selection![2]
+                    && result.endOffset === subpathParams.selection![3]
+                ) return true;
+                if (isAnnotationQuery
+                    && 'annotation' in result
+                    && result.page === subpathParams.page
+                    && result.annotation === subpathParams.annotation
+                ) return true;
+            }
+        }
+
+        return false;
+    }
 }

src/main.ts

@@ -1,6 +1,6 @@
 import { EditableFileView, EventRef, Events, Keymap, Notice, PaneType, Platform, Plugin, TFile, loadPdfJs, requireApiVersion, setIcon } from 'obsidian';
 import * as pdflib from '@cantoo/pdf-lib';
-import * as pdfAnnotate from 'annotpdf';
+// import * as pdfAnnotate from 'annotpdf';
 
 import { patchPDF } from 'patchers/pdf';
 import { patchBacklink } from 'patchers/backlink';
@@ -230,7 +230,7 @@ export default class PDFPlus extends Plugin {
 	private registerGlobalVariables() {
 		this.registerGlobalVariable('pdfPlus', this, false);
 		this.registerGlobalVariable('pdflib', pdflib, false);
-		this.registerGlobalVariable('pdfAnnotate', pdfAnnotate, false);
+		// this.registerGlobalVariable('pdfAnnotate', pdfAnnotate, false);
 	}
 
 	registerGlobalDomEvent<K extends keyof DocumentEventMap>(type: K, callback: (this: HTMLElement, ev: DocumentEventMap[K]) => any, options?: boolean | AddEventListenerOptions): void {