接入原生壳音频文件导出能力

新增 file.exportAudio HostBridge 契约和 H5 facade

移动端通过 Expo 缓存文件与系统分享导出受控音频

桌面端通过 Tauri 保存对话框写入受控音频字节

通用音频输入面板仅对本地音频资产展示宿主导出入口

更新壳能力检查、测试、方案文档和共享决策记录

src/components/common/CreativeAudioInputPanel.test.tsx

@@ -10,6 +10,11 @@ import type { CreativeAudioAsset } from './creativeAudioFileAsset';
 import { CreativeAudioInputPanel } from './CreativeAudioInputPanel';
 
 type TestAudioAsset = CreativeAudioAsset;
+type ExportableTestAudioAsset = TestAudioAsset & {
+  blob: Blob;
+  fileName: string;
+  mimeType: string;
+};
 
 const originalMediaRecorder = globalThis.MediaRecorder;
 const originalMediaDevices = navigator.mediaDevices;
@@ -40,6 +45,18 @@ function buildAsset(overrides: Partial<TestAudioAsset> = {}): TestAudioAsset {
   };
 }
 
+function buildExportableAsset(
+  overrides: Partial<ExportableTestAudioAsset> = {},
+): ExportableTestAudioAsset {
+  return {
+    ...buildAsset(),
+    blob: new Blob(['audio'], { type: 'audio/wav' }),
+    fileName: 'hit.wav',
+    mimeType: 'audio/wav',
+    ...overrides,
+  };
+}
+
 function renderPanel(
   overrides: Partial<
     ComponentProps<typeof CreativeAudioInputPanel<TestAudioAsset>>
@@ -217,6 +234,122 @@ test('原生 App 宿主可用时上传按钮走 HostBridge 音频导入', async
   });
 });
 
+test('原生 App 宿主可用且当前音频为本地资产时可以导出音频', async () => {
+  const invoke = vi.fn(
+    async (_command: string, args?: Record<string, unknown>) => {
+      const request = (args as { request: { id: string } }).request;
+      return {
+        bridge: 'GenarrativeHostBridge',
+        version: 1,
+        id: request.id,
+        ok: true,
+        result: {
+          action: 'saved',
+          fileName: 'hit.wav',
+          bytes: 5,
+        },
+      };
+    },
+  );
+  window.history.replaceState(
+    null,
+    '',
+    '/?clientRuntime=native_app&hostCapabilities=file.exportAudio',
+  );
+  window.__TAURI__ = {
+    core: {
+      invoke: async <Result,>(
+        command: string,
+        args?: Record<string, unknown>,
+      ) => (await invoke(command, args)) as Result,
+    },
+  };
+  const { onError } = renderPanel({
+    asset: buildExportableAsset(),
+  });
+
+  fireEvent.click(screen.getByRole('button', { name: '导出' }));
+
+  await waitFor(() =>
+    expect(invoke).toHaveBeenCalledWith('host_bridge_request', {
+      request: expect.objectContaining({
+        method: 'file.exportAudio',
+        payload: {
+          fileName: 'hit.wav',
+          base64Data: 'YXVkaW8=',
+          mimeType: 'audio/wav',
+        },
+        timeoutMs: 30000,
+      }),
+    }),
+  );
+  expect(onError).toHaveBeenCalledWith(null);
+});
+
+test('非本地音频资产或未声明能力时不显示导出入口', () => {
+  const { rerender } = renderPanel({
+    asset: buildExportableAsset(),
+  });
+
+  expect(screen.queryByRole('button', { name: '导出' })).toBeNull();
+
+  window.history.replaceState(
+    null,
+    '',
+    '/?clientRuntime=native_app&hostCapabilities=file.exportAudio',
+  );
+  rerender(
+    <CreativeAudioInputPanel<TestAudioAsset>
+      title="敲击音效"
+      defaultLabel="默认木鱼音"
+      asset={buildAsset({ audioSrc: '/generated/hit.wav' })}
+      buildRecordedFileName={() => 'recorded-hit.webm'}
+      onAssetChange={() => {}}
+      onError={() => {}}
+    />,
+  );
+
+  expect(screen.queryByRole('button', { name: '导出' })).toBeNull();
+});
+
+test('导出音频失败时提示错误', async () => {
+  const invoke = vi.fn(
+    async (_command: string, args?: Record<string, unknown>) => {
+      const request = (args as { request: { id: string } }).request;
+      return {
+        bridge: 'GenarrativeHostBridge',
+        version: 1,
+        id: request.id,
+        ok: false,
+        error: {
+          code: 'host_error',
+          message: '系统保存失败。',
+        },
+      };
+    },
+  );
+  window.history.replaceState(
+    null,
+    '',
+    '/?clientRuntime=native_app&hostCapabilities=file.exportAudio',
+  );
+  window.__TAURI__ = {
+    core: {
+      invoke: async <Result,>(
+        command: string,
+        args?: Record<string, unknown>,
+      ) => (await invoke(command, args)) as Result,
+    },
+  };
+  const { onError } = renderPanel({
+    asset: buildExportableAsset(),
+  });
+
+  fireEvent.click(screen.getByRole('button', { name: '导出' }));
+
+  await waitFor(() => expect(onError).toHaveBeenCalledWith('系统保存失败。'));
+});
+
 test('上传音频失败时提示错误且不写入资产', async () => {
   const readFileAsAsset = vi.fn(async () => {
     throw new Error('音频最长 1 秒。');

src/components/common/CreativeAudioInputPanel.tsx

@@ -1,8 +1,9 @@
-import { Mic, Pause, Upload } from 'lucide-react';
+import { Download, Mic, Pause, Upload } from 'lucide-react';
 import { useRef, useState } from 'react';
 
 import {
   canUseNativeHostCapability,
+  exportHostAudioFile,
   type HostFileImportAudioResult,
   importHostAudioFile,
 } from '../../services/host-bridge/hostBridge';
@@ -29,6 +30,67 @@ type CreativeAudioInputPanelProps<TAsset extends CreativeAudioAsset> = {
   ) => Promise<TAsset>;
 };
 
+type ExportableCreativeAudioAsset = CreativeAudioAsset & {
+  blob?: Blob;
+  fileName?: string;
+  mimeType?: string;
+};
+
+const HOST_EXPORT_AUDIO_MIME_TYPES = new Set([
+  'audio/mpeg',
+  'audio/mp4',
+  'audio/wav',
+  'audio/ogg',
+  'audio/webm',
+]);
+
+function resolveExportableAudioAsset<TAsset extends CreativeAudioAsset>(
+  asset: TAsset | null,
+) {
+  const candidate = asset as ExportableCreativeAudioAsset | null;
+  if (
+    !candidate?.blob ||
+    !(candidate.blob instanceof Blob) ||
+    !candidate.fileName?.trim() ||
+    !candidate.mimeType?.trim() ||
+    !HOST_EXPORT_AUDIO_MIME_TYPES.has(candidate.mimeType)
+  ) {
+    return null;
+  }
+
+  return {
+    blob: candidate.blob,
+    fileName: candidate.fileName.trim(),
+    mimeType: candidate.mimeType as
+      | 'audio/mpeg'
+      | 'audio/mp4'
+      | 'audio/wav'
+      | 'audio/ogg'
+      | 'audio/webm',
+  };
+}
+
+function blobToBase64Data(blob: Blob) {
+  return new Promise<string>((resolve, reject) => {
+    const reader = new FileReader();
+    reader.onerror = () => reject(new Error('音频导出失败。'));
+    reader.onload = () => {
+      if (typeof reader.result !== 'string') {
+        reject(new Error('音频导出失败。'));
+        return;
+      }
+
+      const base64Data = reader.result.split(',')[1] ?? '';
+      if (!base64Data) {
+        reject(new Error('音频导出失败。'));
+        return;
+      }
+      resolve(base64Data);
+    };
+    reader.readAsDataURL(blob);
+  });
+}
+
 export function CreativeAudioInputPanel<TAsset extends CreativeAudioAsset>({
   disabled = false,
   title,
@@ -41,10 +103,11 @@ export function CreativeAudioInputPanel<TAsset extends CreativeAudioAsset>({
   readFileAsAsset = readCreativeAudioFileAsAsset,
 }: CreativeAudioInputPanelProps<TAsset>) {
   const [isRecording, setIsRecording] = useState(false);
-  const uploadInputRef = useRef<HTMLInputElement | null>(null);
   const recorderRef = useRef<MediaRecorder | null>(null);
   const chunksRef = useRef<BlobPart[]>([]);
   const canImportHostAudio = canUseNativeHostCapability('file.importAudio');
+  const canExportHostAudio = canUseNativeHostCapability('file.exportAudio');
+  const exportableAsset = resolveExportableAudioAsset(asset);
 
   const hostAudioImportResultToFile = (result: HostFileImportAudioResult) => {
     const binary = atob(result.base64Data);
@@ -70,6 +133,22 @@ export function CreativeAudioInputPanel<TAsset extends CreativeAudioAsset>({
     onAssetChange(nextAsset);
   };
 
+  const exportHostAudioAsset = async () => {
+    if (!exportableAsset) {
+      return;
+    }
+
+    const base64Data = await blobToBase64Data(exportableAsset.blob);
+    const exported = await exportHostAudioFile({
+      fileName: exportableAsset.fileName,
+      base64Data,
+      mimeType: exportableAsset.mimeType,
+    });
+    if (exported) {
+      onError(null);
+    }
+  };
+
   const startRecording = async () => {
     if (disabled || isRecording) {
       return;
@@ -140,17 +219,40 @@ export function CreativeAudioInputPanel<TAsset extends CreativeAudioAsset>({
       }
       titleVariant="strong"
       actions={
-        asset ? (
-          <PlatformActionButton
-            onClick={() => onAssetChange(null)}
-            disabled={disabled}
-            tone="ghost"
-            size="xs"
-            className="min-h-0"
-          >
-            重置
-          </PlatformActionButton>
-        ) : null
+        <div className="flex items-center gap-2">
+          {canExportHostAudio && exportableAsset ? (
+            <PlatformActionButton
+              onClick={() => {
+                void exportHostAudioAsset().catch((caughtError) => {
+                  onError(
+                    caughtError instanceof Error
+                      ? caughtError.message
+                      : '音频导出失败。',
+                  );
+                });
+              }}
+              disabled={disabled}
+              tone="ghost"
+              size="xs"
+              className="min-h-0 gap-1"
+              title="导出音频"
+            >
+              <Download className="h-3.5 w-3.5" />
+              导出
+            </PlatformActionButton>
+          ) : null}
+          {asset ? (
+            <PlatformActionButton
+              onClick={() => onAssetChange(null)}
+              disabled={disabled}
+              tone="ghost"
+              size="xs"
+              className="min-h-0"
+            >
+              重置
+            </PlatformActionButton>
+          ) : null}
+        </div>
       }
       bodyClassName="mt-3 flex flex-wrap items-center gap-2"
     >
@@ -181,7 +283,6 @@ export function CreativeAudioInputPanel<TAsset extends CreativeAudioAsset>({
         <Upload className="h-4 w-4" />
         上传
         <input
-          ref={uploadInputRef}
           type="file"
           accept="audio/*"
           disabled={disabled}