按接口能力展示讲解语言

tests/unit/ExhibitDetailAudioFirst.spec.ts

@@ -86,7 +86,8 @@ const exhibit = {
   audioLanguage: 'en-US',
   audioHasText: false,
   playTargetType: 'STOP',
-  playTargetId: 'stop-1'
+  playTargetId: 'stop-1',
+  supportedLanguages: ['zh-CN', 'yue-HK', 'en-US']
 }
 
 describe('讲解详情音频优先布局', () => {
@@ -148,6 +149,59 @@ describe('讲解详情音频优先布局', () => {
     expect(wrapper.get('.section-text').text()).toContain('detailed English narration')
   })
 
+  it('仅展示 stop-info 声明支持的语言按钮', async () => {
+    mocks.enterExplainDetail.mockResolvedValue({
+      ...exhibit,
+      supportedLanguages: ['zh-CN', 'en-US']
+    })
+    const wrapper = mount(ExhibitDetail, {
+      global: { stubs: { GuidePageFrame: GuidePageFrameStub } }
+    })
+
+    await mocks.onLoadHandler?.({ id: exhibit.id, lang: 'zh-CN', targetType: 'STOP', targetId: 'stop-1' })
+    await flushPromises()
+
+    const labels = wrapper.findAll('.language-option-text').map((node) => node.text())
+    expect(labels).toEqual(['中文', 'English'])
+    expect(labels).not.toContain('粤语')
+  })
+
+  it('无支持语言时不显示语言栏', async () => {
+    mocks.enterExplainDetail.mockResolvedValue({
+      ...exhibit,
+      supportedLanguages: []
+    })
+    const wrapper = mount(ExhibitDetail, {
+      global: { stubs: { GuidePageFrame: GuidePageFrameStub } }
+    })
+
+    await mocks.onLoadHandler?.({ id: exhibit.id, lang: 'zh-CN', targetType: 'STOP', targetId: 'stop-1' })
+    await flushPromises()
+
+    expect(wrapper.find('.detail-language-bar').exists()).toBe(false)
+  })
+
+  it('深链语言不受支持时回退至中文并规范化地址', async () => {
+    mocks.enterExplainDetail.mockImplementation(async (request: { lang: string }) => ({
+      ...exhibit,
+      audioLanguage: request.lang,
+      supportedLanguages: ['zh-CN']
+    }))
+    const replaceState = vi.spyOn(window.history, 'replaceState')
+    const wrapper = mount(ExhibitDetail, {
+      global: { stubs: { GuidePageFrame: GuidePageFrameStub } }
+    })
+
+    await mocks.onLoadHandler?.({ id: exhibit.id, lang: 'en-US', targetType: 'STOP', targetId: 'stop-1' })
+    await flushPromises()
+
+    expect(mocks.enterExplainDetail).toHaveBeenNthCalledWith(1, expect.objectContaining({ lang: 'en-US' }))
+    expect(mocks.enterExplainDetail).toHaveBeenNthCalledWith(2, expect.objectContaining({ lang: 'zh-CN' }))
+    expect(wrapper.get('.language-option').classes()).toContain('active')
+    expect(wrapper.get('.language-option-text').text()).toBe('中文')
+    expect(replaceState).toHaveBeenCalledWith(null, '', expect.stringContaining('lang=zh-CN'))
+  })
+
   it('通过同一全局音频播放器开始播放，不创建页面播放器', async () => {
     const wrapper = mount(ExhibitDetail, {
       global: { stubs: { GuidePageFrame: GuidePageFrameStub } }