修复讲解列表嵌入小程序标题回退

- 同步讲解列表层级标题到宿主导航栏
- 嵌入小程序时为展厅/业务单元层级写入 H5 历史
- 保留普通 H5 自绘标题和返回行为

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/pages/explain/list.vue

@@ -28,8 +28,8 @@
 </template>
 
 <script setup lang="ts">
-import { computed, ref } from 'vue'
-import { onLoad } from '@dcloudio/uni-app'
+import { computed, ref, watch } from 'vue'
+import { onLoad, onUnload } from '@dcloudio/uni-app'
 import GuidePageFrame from '@/components/navigation/GuidePageFrame.vue'
 import ExplainHallSelect, {
   type ExplainBusinessUnitSelectItem,
@@ -51,6 +51,7 @@ import {
   navigateToGuideTopTab,
   type GuideTopTab
 } from '@/utils/guideTopTabs'
+import { isEmbeddedInWechatMiniProgram } from '@/utils/hostEnvironment'
 
 const explainHallItems = ref<ExplainHallSelectItem[]>([])
 const explainBusinessUnits = ref<ExplainBusinessUnit[]>([])
@@ -89,6 +90,24 @@ const buildExplainHallItems = (
 const selectedExplainBusinessUnit = computed(() => (
   explainBusinessUnits.value.find((unit) => unit.id === selectedExplainBusinessUnitId.value) || null
 ))
+const explainPageTitle = computed(() => {
+  if (explainStage.value === 'unit') return selectedExplainHallName.value || '选择业务单元'
+  if (explainStage.value === 'stop') return selectedExplainBusinessUnitName.value || '选择讲解点'
+  return '讲解'
+})
+const shouldUseHostNavigation = computed(() => isEmbeddedInWechatMiniProgram())
+
+const syncHostNavigationTitle = () => {
+  const title = explainPageTitle.value
+
+  if (typeof uni !== 'undefined') {
+    uni.setNavigationBarTitle({ title })
+  }
+
+  if (typeof document !== 'undefined') {
+    document.title = title
+  }
+}
 
 const explainBusinessUnitItems = computed<ExplainBusinessUnitSelectItem[]>(() => (
   explainBusinessUnits.value.map((unit) => ({
@@ -120,6 +139,125 @@ const explainGuideStopItems = computed<ExplainGuideStopSelectItem[]>(() => (
   })) || []
 ))
 
+type ExplainHistoryState = {
+  museumExplainList?: boolean
+  stage?: ExplainSelectStage
+  hallId?: string
+  hallName?: string
+  unitId?: string
+  unitName?: string
+}
+
+let syncingExplainHistory = false
+let applyingExplainHistory = false
+
+const stageRank: Record<ExplainSelectStage, number> = {
+  hall: 0,
+  unit: 1,
+  stop: 2
+}
+
+const currentExplainHistoryState = (): ExplainHistoryState => ({
+  museumExplainList: true,
+  stage: explainStage.value,
+  hallId: selectedExplainHallId.value,
+  hallName: selectedExplainHallName.value,
+  unitId: selectedExplainBusinessUnitId.value,
+  unitName: selectedExplainBusinessUnitName.value
+})
+
+const writeExplainHistoryState = (replace = false) => {
+  if (!shouldUseHostNavigation.value || typeof window === 'undefined') return
+
+  syncingExplainHistory = true
+  const state = currentExplainHistoryState()
+  const url = window.location.href
+
+  if (replace) {
+    window.history.replaceState(state, '', url)
+  } else {
+    window.history.pushState(state, '', url)
+  }
+
+  window.setTimeout(() => {
+    syncingExplainHistory = false
+  }, 0)
+}
+
+const applyExplainHistoryState = async (state: ExplainHistoryState | null) => {
+  if (!state?.museumExplainList || applyingExplainHistory) return
+
+  applyingExplainHistory = true
+  const targetStage = state.stage || 'hall'
+
+  if (targetStage === 'hall') {
+    explainStage.value = 'hall'
+    selectedExplainHallId.value = ''
+    selectedExplainHallName.value = ''
+    selectedExplainBusinessUnitId.value = ''
+    selectedExplainBusinessUnitName.value = ''
+    explainBusinessUnits.value = []
+    explainError.value = ''
+    applyingExplainHistory = false
+    return
+  }
+
+  if (state.hallId) {
+    selectedExplainHallId.value = state.hallId
+    selectedExplainHallName.value = state.hallName || '业务单元'
+    selectedExplainBusinessUnitId.value = ''
+    selectedExplainBusinessUnitName.value = ''
+    explainStage.value = 'unit'
+
+    if (!explainBusinessUnits.value.length || explainBusinessUnits.value[0]?.hallId !== state.hallId) {
+      explainLoading.value = true
+      explainError.value = ''
+      try {
+        explainBusinessUnits.value = await explainUseCase.loadTemporaryBusinessUnitsByHall(state.hallId)
+      } catch (error) {
+        console.error('恢复展厅讲解点失败:', error)
+        explainError.value = '展厅讲解点加载失败，请稍后重试'
+        explainBusinessUnits.value = []
+      } finally {
+        explainLoading.value = false
+      }
+    }
+  }
+
+  if (targetStage === 'stop' && state.unitId) {
+    selectedExplainBusinessUnitId.value = state.unitId
+    selectedExplainBusinessUnitName.value = state.unitName || '讲解点'
+    explainStage.value = 'stop'
+  }
+
+  applyingExplainHistory = false
+}
+
+const handleExplainHistoryPopState = (event: PopStateEvent) => {
+  if (syncingExplainHistory) return
+  void applyExplainHistoryState((event.state || null) as ExplainHistoryState | null)
+}
+
+const pushExplainStageHistory = (previousStage: ExplainSelectStage) => {
+  if (!shouldUseHostNavigation.value || applyingExplainHistory) return
+  if (stageRank[explainStage.value] <= stageRank[previousStage]) return
+
+  writeExplainHistoryState()
+}
+
+const replaceExplainStageHistory = () => {
+  writeExplainHistoryState(true)
+}
+
+watch(explainPageTitle, syncHostNavigationTitle)
+
+watch(shouldUseHostNavigation, (value) => {
+  if (value) {
+    syncHostNavigationTitle()
+    replaceExplainStageHistory()
+  }
+})
+
 const loadExplainHalls = async () => {
   if (explainHallItems.value.length) return
   if (explainLoadPromise) return explainLoadPromise
@@ -146,7 +284,19 @@ const loadExplainHalls = async () => {
 }
 
 onLoad(() => {
+  syncHostNavigationTitle()
+  replaceExplainStageHistory()
   void loadExplainHalls()
+
+  if (typeof window !== 'undefined') {
+    window.addEventListener('popstate', handleExplainHistoryPopState)
+  }
+})
+
+onUnload(() => {
+  if (typeof window !== 'undefined') {
+    window.removeEventListener('popstate', handleExplainHistoryPopState)
+  }
 })
 
 const handleBack = () => {
@@ -170,6 +320,7 @@ const handleTopTabChange = (tab: GuideTopTab) => {
 }
 
 const handleExplainHallClick = async (hallId: string) => {
+  const previousStage = explainStage.value
   const hall = explainHallItems.value.find((item) => item.id === hallId)
   selectedExplainHallId.value = hallId
   selectedExplainHallName.value = hall?.name || '业务单元'
@@ -182,20 +333,24 @@ const handleExplainHallClick = async (hallId: string) => {
   try {
     explainBusinessUnits.value = await explainUseCase.loadTemporaryBusinessUnitsByHall(hallId)
     explainStage.value = 'unit'
+    pushExplainStageHistory(previousStage)
   } catch (error) {
     console.error('加载展厅讲解点失败:', error)
     explainError.value = '展厅讲解点加载失败，请稍后重试'
     explainStage.value = 'unit'
+    pushExplainStageHistory(previousStage)
   } finally {
     explainLoading.value = false
   }
 }
 
 const handleExplainBusinessUnitClick = (unitId: string) => {
+  const previousStage = explainStage.value
   const unit = explainBusinessUnits.value.find((item) => item.id === unitId)
   selectedExplainBusinessUnitId.value = unitId
   selectedExplainBusinessUnitName.value = unit?.name || '讲解点'
   explainStage.value = 'stop'
+  pushExplainStageHistory(previousStage)
 }
 
 const handleExplainGuideStopClick = (stop: ExplainGuideStopSelectItem) => {
@@ -222,6 +377,7 @@ const handlePanelBack = () => {
     selectedExplainBusinessUnitId.value = ''
     selectedExplainBusinessUnitName.value = ''
     explainError.value = ''
+    replaceExplainStageHistory()
     return
   }
 
@@ -233,6 +389,7 @@ const handlePanelBack = () => {
     selectedExplainBusinessUnitName.value = ''
     explainBusinessUnits.value = []
     explainError.value = ''
+    replaceExplainStageHistory()
     return
   }