fix(web-integration): reuse static UI context (#3089)

Author: EAGzzyCSL

packages/web-integration/src/static/static-agent.ts

@@ -1,10 +1,18 @@
 import { Agent as PageAgent } from '@midscene/core/agent';
+import type { UIContext } from '@midscene/core';
 import type StaticPage from './static-page';
 
 export class StaticPageAgent extends PageAgent {
+  private readonly staticPage: StaticPage;
+
   constructor(page: StaticPage) {
     // Disable report generation in browser environment to avoid Node.js fs module errors
     super(page, { generateReport: false });
+    this.staticPage = page;
     this.dryMode = true;
   }
+
+  override async getUIContext(): Promise<UIContext> {
+    return this.staticPage.getUIContext();
+  }
 }

packages/web-integration/src/static/static-page.ts

@@ -4,6 +4,7 @@ import type {
   ScreenshotRef,
   UIContext,
 } from '@midscene/core';
+import { ScreenshotItem } from '@midscene/core';
 import type { AbstractInterface } from '@midscene/core/device';
 import {
   type InputPrimitives,
@@ -25,9 +26,12 @@ type SerializedStaticScreenshot = {
 
 type StaticPageUIContext = Omit<
   UIContext,
-  'deprecatedDpr' | 'screenshot'
+  'deprecatedDpr' | 'screenshot' | 'screenshotSequence'
 > & {
   screenshot: UIContext['screenshot'] | SerializedStaticScreenshot;
+  screenshotSequence?: Array<
+    UIContext['screenshot'] | SerializedStaticScreenshot
+  >;
 };
 
 function screenshotBase64FromContext(
@@ -50,10 +54,38 @@ function screenshotBase64FromContext(
   );
 }
 
+function screenshotItemFromContext(
+  screenshot: StaticPageUIContext['screenshot'],
+): ScreenshotItem {
+  if (screenshot instanceof ScreenshotItem) {
+    return screenshot;
+  }
+
+  const capturedAt =
+    typeof screenshot.capturedAt === 'number'
+      ? screenshot.capturedAt
+      : Date.now();
+  return ScreenshotItem.create(
+    screenshotBase64FromContext(screenshot),
+    capturedAt,
+  );
+}
+
+function normalizeUIContext(uiContext: StaticPageUIContext): UIContext {
+  return {
+    ...uiContext,
+    screenshot: screenshotItemFromContext(uiContext.screenshot),
+    screenshotSequence: uiContext.screenshotSequence?.map(
+      screenshotItemFromContext,
+    ),
+  };
+}
+
 export default class StaticPage implements AbstractInterface {
   interfaceType = 'static';
 
   private uiContext: StaticPageUIContext;
+  private normalizedUIContext?: UIContext;
   readonly inputPrimitives: InputPrimitives = {
     pointer: {
       tap: async () => ThrowNotImplemented('Tap'),
@@ -78,6 +110,11 @@ export default class StaticPage implements AbstractInterface {
     this.uiContext = uiContext;
   }
 
+  getUIContext(): UIContext {
+    this.normalizedUIContext ??= normalizeUIContext(this.uiContext);
+    return this.normalizedUIContext;
+  }
+
   actionSpace(): DeviceAction[] {
     // Return available actions for static page - they will throw "not implemented" errors when executed
     // but need to be available for planning phase
@@ -175,5 +212,6 @@ export default class StaticPage implements AbstractInterface {
 
   updateContext(newContext: StaticPageUIContext): void {
     this.uiContext = newContext;
+    this.normalizedUIContext = undefined;
   }
 }

packages/web-integration/tests/unit-test/static-page.test.ts

@@ -1,6 +1,6 @@
 import { ScreenshotItem } from '@midscene/core';
 import { describe, expect, it } from '@rstest/core';
-import { StaticPage } from '../../src/static';
+import { StaticPage, StaticPageAgent } from '../../src/static';
 
 const screenshotBase64 = 'data:image/png;base64,abc123';
 
@@ -53,4 +53,31 @@ describe('StaticPage', () => {
       'serialized reference without base64 data',
     );
   });
+
+  it('lets StaticPageAgent reuse the prepared UI context', async () => {
+    const capturedAt = 123;
+    const page = new StaticPage(
+      createContext({ base64: screenshotBase64, capturedAt }),
+    );
+    const agent = new StaticPageAgent(page);
+
+    const context = await agent.getUIContext();
+
+    expect(context.shotSize).toEqual({ width: 800, height: 600 });
+    expect(context.shrunkShotToLogicalRatio).toBe(1);
+    expect(context.screenshot).toBeInstanceOf(ScreenshotItem);
+    expect(context.screenshot.base64).toBe(screenshotBase64);
+    expect(context.screenshot.capturedAt).toBe(capturedAt);
+
+    const updatedScreenshotBase64 = 'data:image/png;base64,updated';
+    page.updateContext(
+      createContext({ base64: updatedScreenshotBase64, capturedAt: 456 }),
+    );
+
+    const updatedContext = await agent.getUIContext();
+
+    expect(updatedContext).not.toBe(context);
+    expect(updatedContext.screenshot.base64).toBe(updatedScreenshotBase64);
+    expect(updatedContext.screenshot.capturedAt).toBe(456);
+  });
 });