fix: use skia-canvas with pdfjs to avoid N-API errors (#2281)

Use custom CanvasFactory for pdfjs so we can continue to use
skia-canvas.

packages/lib/server-only/ai/pdf-to-images.ts

@@ -1,6 +1,41 @@
-import { createCanvas } from '@napi-rs/canvas';
 import pMap from 'p-map';
 import * as pdfjsLib from 'pdfjs-dist/legacy/build/pdf.mjs';
+import { Canvas, Image, Path2D } from 'skia-canvas';
+
+// @ts-expect-error napi-rs/canvas satisfies the requirements
+globalThis.Path2D = Path2D;
+// @ts-expect-error napi-rs/canvas satisfies the requirements
+globalThis.Image = Image;
+
+class SkiaCanvasFactory {
+  _createCanvas(width: number, height: number) {
+    return new Canvas(width, height);
+  }
+
+  create(width: number, height: number) {
+    const canvas = this._createCanvas(width, height);
+
+    return {
+      canvas,
+      context: canvas.getContext('2d'),
+    };
+  }
+
+  reset(canvasAndContext: { canvas: Canvas }, width: number, height: number) {
+    canvasAndContext.canvas.width = width;
+    canvasAndContext.canvas.height = height;
+  }
+
+  destroy(canvasAndContext: { canvas: Canvas | null; context: unknown }) {
+    if (canvasAndContext.canvas) {
+      canvasAndContext.canvas.width = 0;
+      canvasAndContext.canvas.height = 0;
+    }
+
+    canvasAndContext.canvas = null;
+    canvasAndContext.context = null;
+  }
+}
 
 export type PdfToImagesOptions = {
   scale?: number;
@@ -9,7 +44,10 @@ export type PdfToImagesOptions = {
 export const pdfToImages = async (pdfBytes: Uint8Array, options: PdfToImagesOptions = {}) => {
   const { scale = 2 } = options;
 
-  const pdf = await pdfjsLib.getDocument(pdfBytes).promise;
+  const pdf = await pdfjsLib.getDocument({
+    data: pdfBytes,
+    CanvasFactory: SkiaCanvasFactory,
+  }).promise;
 
   const images = await pMap(
     Array.from({ length: pdf.numPages }),
@@ -19,7 +57,7 @@ export const pdfToImages = async (pdfBytes: Uint8Array, options: PdfToImagesOpti
 
       const viewport = page.getViewport({ scale });
 
-      const canvas = createCanvas(viewport.width, viewport.height);
+      const canvas = new Canvas(viewport.width, viewport.height);
       const canvasContext = canvas.getContext('2d');
 
       await page.render({
@@ -32,7 +70,7 @@ export const pdfToImages = async (pdfBytes: Uint8Array, options: PdfToImagesOpti
 
       return {
         pageNumber,
-        image: await canvas.encode('jpeg'),
+        image: await canvas.toBuffer('jpeg'),
         width: Math.floor(viewport.width),
         height: Math.floor(viewport.height),
         mimeType: 'image/jpeg',