feat: 实现 DOCX 媒体预处理与跨端 PNG 捕获

apps/server/src/playwright-docx-media-capture.ts

@@ -0,0 +1,75 @@
+import type { Page } from "playwright";
+import type {
+  DocxMediaCaptureAdapter,
+  DocxMediaCaptureRequest
+} from "@md-to-pdf/application";
+import type { DocxMediaCapturePlan } from "@md-to-pdf/core";
+
+interface CaptureScreenshotResult {
+  data: string;
+}
+
+async function renderCapturePlan(
+  page: Page,
+  request: DocxMediaCaptureRequest
+) {
+  return page.evaluate(
+    async ({ payload, dimensions }): Promise<DocxMediaCapturePlan> => {
+      const renderer = (
+        window as typeof window & {
+          __mdToPdfRenderDocxMedia?: (
+            renderPayload: typeof payload,
+            renderDimensions: typeof dimensions
+          ) => Promise<DocxMediaCapturePlan>;
+        }
+      ).__mdToPdfRenderDocxMedia;
+      if (!renderer) {
+        throw new Error("DOCX 媒体渲染运行时不可用");
+      }
+      return renderer(payload, dimensions);
+    },
+    request
+  );
+}
+
+export async function captureDocxMediaWithPlaywrightPage(
+  page: Page,
+  request: DocxMediaCaptureRequest
+) {
+  const plan = await renderCapturePlan(page, request);
+  const session = await page.context().newCDPSession(page);
+  try {
+    const captures = [];
+    for (const target of plan.targets) {
+      const result = (await session.send("Page.captureScreenshot", {
+        format: "png",
+        fromSurface: true,
+        captureBeyondViewport: true,
+        clip: {
+          x: target.captureX,
+          y: target.captureY,
+          width: target.captureWidthPx,
+          height: target.captureHeightPx,
+          scale: target.rasterScale
+        }
+      })) as CaptureScreenshotResult;
+      captures.push({
+        id: target.id,
+        png: Buffer.from(result.data, "base64")
+      });
+    }
+    return { plan, captures };
+  } finally {
+    await session.detach();
+  }
+}
+
+export class PlaywrightDocxMediaCaptureAdapter
+  implements DocxMediaCaptureAdapter
+{
+  constructor(private readonly page: Page) {}
+
+  capture(request: DocxMediaCaptureRequest) {
+    return captureDocxMediaWithPlaywrightPage(this.page, request);
+  }
+}