[Desktop] Fix torch mirror setting (#2475)

src/components/install/MirrorsConfiguration.vue

@@ -80,11 +80,28 @@ const getTorchMirrorItem = (device: TorchDeviceType): UVMirror => {
   }
 }
 
-const mirrors = computed<[UVMirror, ModelRef<string>][]>(() => [
-  [PYTHON_MIRROR, pythonMirror],
-  [PYPI_MIRROR, pypiMirror],
-  [getTorchMirrorItem(device), torchMirror]
-])
+const userIsInChina = ref(false)
+onMounted(async () => {
+  userIsInChina.value = await isInChina()
+})
+
+const useFallbackMirror = (mirror: UVMirror) => ({
+  ...mirror,
+  mirror: mirror.fallbackMirror
+})
+
+const mirrors = computed<[UVMirror, ModelRef<string>][]>(() =>
+  (
+    [
+      [PYTHON_MIRROR, pythonMirror],
+      [PYPI_MIRROR, pypiMirror],
+      [getTorchMirrorItem(device), torchMirror]
+    ] as [UVMirror, ModelRef<string>][]
+  ).map(([item, modelValue]) => [
+    userIsInChina.value ? useFallbackMirror(item) : item,
+    modelValue
+  ])
+)
 
 const validationStates = ref<ValidationState[]>(
   mirrors.value.map(() => ValidationState.IDLE)
@@ -102,13 +119,4 @@ const validationStateTooltip = computed(() => {
       return t('install.settings.checkingMirrors')
   }
 })
-
-onMounted(async () => {
-  // Check if user is in China and set fallback mirrors directly
-  if (await isInChina()) {
-    for (const [item, modelValue] of mirrors.value) {
-      modelValue.value = item.fallbackMirror
-    }
-  }
-})
 </script>

src/components/install/mirror/MirrorItem.vue

@@ -44,10 +44,7 @@ const normalizedSettingId = computed(() => {
 })
 
 onMounted(() => {
-  // Set mirror value if not already set
-  if (!modelValue.value) {
-    modelValue.value = item.mirror
-  }
+  modelValue.value = item.mirror
 })
 
 watch(validationState, (newState) => {