fix(video): 预加载Video.js资源并优化视频播放诊断

- 在HomePage和StudyDetailPage添加Video.js资源预加载函数，解决首次播放黑屏问题
- 为VideoPlayer组件添加加载状态占位符，改善用户体验
- 增强视频播放错误处理和调试日志，便于问题排查
- 修复play()方法调用时的Promise处理，避免静默失败
- 优化跨域视频加载配置和网络超时设置

@@ -15,6 +15,7 @@
       x5-video-player-type="h5"
       x5-video-player-fullscreen="true"
       preload="metadata"
+      crossorigin="anonymous"
       @play="handleNativePlay"
       @pause="handleNativePause"
     />
@@ -31,6 +32,12 @@
       @pause="handlePause"
     />
 
+    <!-- Loading 占位符：Video.js 资源加载时显示 -->
+    <div v-if="!useNativePlayer && !state" class="loading-placeholder">
+      <div class="loading-spinner"></div>
+      <div class="loading-text">视频加载中...</div>
+    </div>
+
     <!-- <div v-if="showNetworkSpeedOverlay && !showErrorOverlay" class="speed-overlay">
       <div class="speed-content">
         <div
@@ -45,9 +52,8 @@
       </div>
     </div> -->
 
-    <div v-if="hlsDownloadSpeedText" class="hls-speed-badge">{{ hlsDownloadSpeedText }}</div>
-    <div v-if="props.debug" class="hls-debug-badge">
-      {{ hlsSpeedDebugText || "debug:empty" }}
+    <div v-if="hlsDownloadSpeedText && !props.debug" class="hls-speed-badge">
+      {{ hlsDownloadSpeedText }}
     </div>
 
     <!-- 错误提示覆盖层 -->
@@ -62,17 +68,17 @@
 </template>
 
 <script setup>
-import { defineAsyncComponent, ref } from "vue";
-import { useVideoPlayer } from "@/composables/useVideoPlayer";
+import { defineAsyncComponent, ref, computed, watch } from 'vue'
+import { useVideoPlayer } from '@/composables/useVideoPlayer'
 
 const VideoPlayer = defineAsyncComponent(async () => {
-  await import("video.js/dist/video-js.css");
-  await import("videojs-hls-quality-selector/dist/videojs-hls-quality-selector.css");
-  await import("videojs-contrib-quality-levels");
-  await import("videojs-hls-quality-selector");
-  const mod = await import("@videojs-player/vue");
-  return mod.VideoPlayer;
-});
+  await import('video.js/dist/video-js.css')
+  await import('videojs-hls-quality-selector/dist/videojs-hls-quality-selector.css')
+  await import('videojs-contrib-quality-levels')
+  await import('videojs-hls-quality-selector')
+  const mod = await import('@videojs-player/vue')
+  return mod.VideoPlayer
+})
 
 const props = defineProps({
   options: {
@@ -95,7 +101,7 @@ const props = defineProps({
   },
   debug: {
     type: Boolean,
-    default: false
+    default: false,
   },
   /**
    * iOS 环境下是否强制使用原生播放器
@@ -103,14 +109,14 @@ const props = defineProps({
    */
   useNativeOnIos: {
     type: Boolean,
-    default: true
-  }
-});
+    default: true,
+  },
+})
 
-const emit = defineEmits(["onPlay", "onPause"]);
+const emit = defineEmits(['onPlay', 'onPause'])
 
-const videoRef = ref(null);
-const nativeVideoRef = ref(null);
+const videoRef = ref(null)
+const nativeVideoRef = ref(null)
 
 const {
   player,
@@ -127,68 +133,137 @@ const {
   hlsSpeedDebugText,
   retryLoad,
   handleVideoJsMounted,
-  tryNativePlay
-} = useVideoPlayer(props, emit, videoRef, nativeVideoRef);
+  tryNativePlay,
+} = useVideoPlayer(props, emit, videoRef, nativeVideoRef)
+
+// 视频加载诊断（控制台日志）
+const logVideoDiagnostics = () => {
+  if (!props.debug) return
+
+  const isSameOrigin = (() => {
+    if (typeof window === 'undefined' || !props.videoUrl) return false
+    try {
+      const videoUrl = new URL(props.videoUrl, window.location.href)
+      return videoUrl.origin === window.location.origin
+    } catch {
+      return false
+    }
+  })()
+
+  // 检查是否为 HLS 视频
+  const checkIsM3U8 = url => {
+    if (!url) return false
+    return url.toLowerCase().includes('.m3u8')
+  }
+
+  console.group('🎬 [VideoPlayer] 视频加载诊断')
+  console.log('📌 URL:', videoUrlValue.value)
+  console.log('🔗 同源:', isSameOrigin)
+  console.log('🎥 播放器类型:', useNativePlayer.value ? '原生播放器' : 'Video.js')
+  console.log('📦 挂载状态:', state.value ? '已挂载' : '加载中')
+  console.log('🌐 HLS支持:', checkIsM3U8(videoUrlValue.value) ? '是' : '否')
+  console.groupEnd()
+}
+
+// 监听视频加载状态变化
+watch(
+  () => [state.value, showErrorOverlay.value, errorMessage.value],
+  ([currentState, showError, errorMsg]) => {
+    if (props.debug) {
+      console.group('🎬 [VideoPlayer] 状态变化')
+      console.log('📊 当前状态:', currentState ? '已挂载' : '加载中')
+      console.log('❌ 错误状态:', showError ? errorMsg : '无')
+      console.groupEnd()
+    }
+
+    if (showError && props.debug) {
+      console.group('❌ [VideoPlayer] 错误诊断')
+      console.error('错误信息:', errorMsg)
+      console.log('视频URL:', videoUrlValue.value)
+      console.log('播放器类型:', useNativePlayer.value ? '原生' : 'Video.js')
+      console.log('排查建议:')
+      console.log('  1. 检查 CDN 服务器是否正常运行')
+      console.log('  2. 检查 CORS 跨域配置是否正确')
+      console.log('  3. 检查网络连接是否稳定')
+      console.log('  4. 检查视频文件格式是否支持')
+      console.groupEnd()
+    }
+
+    // 每次状态变化都输出诊断信息
+    if (currentState) {
+      logVideoDiagnostics()
+    }
+  },
+  { immediate: true }
+)
 
 // 事件处理
 /**
  * @description 处理播放事件
  * @param {Event|Object} payload - 事件对象或数据
  */
-const handlePlay = (payload) => emit("onPlay", payload);
+const handlePlay = payload => {
+  if (props.debug) {
+    console.log('🎬 [VideoPlayer] 视频开始播放', payload)
+  }
+  emit('onPlay', payload)
+}
 
 /**
  * @description 处理暂停事件
  * @param {Event|Object} payload - 事件对象或数据
  */
-const handlePause = (payload) => emit("onPause", payload);
+const handlePause = payload => {
+  if (props.debug) {
+    console.log('⏸️ [VideoPlayer] 视频暂停', payload)
+  }
+  emit('onPause', payload)
+}
 
 /**
  * @description 处理原生播放事件
  * @param {Event} event - 事件对象
  */
-const handleNativePlay = (event) => emit("onPlay", event);
+const handleNativePlay = event => emit('onPlay', event)
 
 /**
  * @description 处理原生暂停事件
  * @param {Event} event - 事件对象
  */
-const handleNativePause = (event) => emit("onPause", event);
+const handleNativePause = event => emit('onPause', event)
 
 // 暴露方法给父组件
 defineExpose({
   pause() {
     if (useNativePlayer.value) {
       try {
-        nativeVideoRef.value?.pause?.();
-        emit('onPause', nativeVideoRef.value);
-      } catch (e) {
-      }
-      return;
+        nativeVideoRef.value?.pause?.()
+        emit('onPause', nativeVideoRef.value)
+      } catch (e) {}
+      return
     }
 
     if (player.value && !player.value.isDisposed()) {
       try {
-        player.value.pause();
-        emit('onPause', player.value);
-      } catch (e) {
-      }
+        player.value.pause()
+        emit('onPause', player.value)
+      } catch (e) {}
     }
   },
   play() {
     if (useNativePlayer.value) {
-      tryNativePlay();
-      return;
+      tryNativePlay()
+      return
     }
-    player.value?.play()?.catch(() => {});
+    player.value?.play()?.catch(() => {})
   },
   getPlayer() {
-    return useNativePlayer.value ? nativeVideoRef.value : player.value;
+    return useNativePlayer.value ? nativeVideoRef.value : player.value
   },
   getId() {
-    return props.videoId || "meta_id";
+    return props.videoId || 'meta_id'
   },
-});
+})
 </script>
 
 <style scoped>
@@ -207,7 +282,43 @@ defineExpose({
 }
 
 .video-player.loading {
-  opacity: 0.6;
+  opacity: 0;
+}
+
+/* Loading 占位符样式 */
+.loading-placeholder {
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  background: #000;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  z-index: 1;
+}
+
+.loading-spinner {
+  width: 40px;
+  height: 40px;
+  border: 3px solid rgba(255, 255, 255, 0.3);
+  border-top-color: #4caf50;
+  border-radius: 50%;
+  animation: spin 1s linear infinite;
+}
+
+@keyframes spin {
+  to {
+    transform: rotate(360deg);
+  }
+}
+
+.loading-text {
+  margin-top: 12px;
+  color: rgba(255, 255, 255, 0.8);
+  font-size: 14px;
 }
 
 /* 错误覆盖层样式 */

@@ -368,6 +368,7 @@
                   </template>
                   <VideoPlayer
                     v-else
+                    :key="`video_${index}_${item.video_url}`"
                     :video-url="item.video_url"
                     :video-id="`home_recommend_video_${index}`"
                     :use-native-on-ios="false"
@@ -394,6 +395,16 @@ import LiveStreamCard from '@/components/courses/LiveStreamCard.vue'
 import VideoPlayer from '@/components/media/VideoPlayer.vue'
 import CheckInList from '@/components/checkin/CheckInList.vue'
 
+// Video.js 资源预加载（解决首次播放黑屏问题）
+const preloadVideoJs = () => {
+  // 在用户可能点击视频前，预先加载 Video.js 资源
+  import('video.js/dist/video-js.css')
+  import('videojs-hls-quality-selector/dist/videojs-hls-quality-selector.css')
+  import('videojs-contrib-quality-levels')
+  import('videojs-hls-quality-selector')
+  import('@videojs-player/vue')
+}
+
 import FeaturedCoursesSection from '@/components/homePage/FeaturedCoursesSection.vue'
 import RecommendationsSection from '@/components/homePage/RecommendationsSection.vue'
 import LatestActivitiesSection from '@/components/homePage/LatestActivitiesSection.vue'
@@ -431,6 +442,9 @@ const activeTab = ref('推荐') // 当前激活的内容标签页
 const checkInTypes = ref([])
 
 onMounted(() => {
+  // 预加载 Video.js 资源，避免首次播放时黑屏
+  preloadVideoJs()
+
   watch(
     () => currentUser.value,
     async newVal => {