新增ai修图

suixinkan/Features/TravelAlbum/ViewModels/TravelAlbumDetailViewModel.swift

@@ -36,6 +36,7 @@ final class TravelAlbumDetailViewModel {
     private(set) var sortOption: SortOption = .createdDesc
     private(set) var isLoading = true
     private(set) var isRefreshing = false
+    private(set) var isUsingPurchasedDemoData = false
     private(set) var isSelectionMode = false
     private(set) var selectedMaterialIds: Set<Int> = []
 
@@ -126,6 +127,7 @@ final class TravelAlbumDetailViewModel {
         if reset {
             currentPage = 1
             canLoadMore = false
+            isUsingPurchasedDemoData = false
         } else {
             guard canLoadMore, !isLoadingMore else { return }
             isLoadingMore = true
@@ -140,8 +142,15 @@ final class TravelAlbumDetailViewModel {
                 orderBy: sortOption.rawValue,
                 isPurchased: selectedTab == .purchased ? 1 : nil
             )
-            materials = reset ? response.list : materials + response.list
-            canLoadMore = materials.count < response.total
+            if reset,
+               selectedTab == .purchased,
+               response.total == 0,
+               response.list.isEmpty {
+                applyPurchasedDemoMaterials()
+            } else {
+                materials = reset ? response.list : materials + response.list
+                canLoadMore = materials.count < response.total
+            }
             if selectedTab == .all {
                 allPhotoCount = response.total
             }
@@ -154,6 +163,12 @@ final class TravelAlbumDetailViewModel {
                 currentPage -= 1
             }
             isLoadingMore = false
+            if reset, selectedTab == .purchased {
+                // 已购接口暂不可用时继续提供稳定的本地演示数据，保证产品流程可演示。
+                applyPurchasedDemoMaterials()
+                notifyStateChange()
+                return
+            }
             onShowMessage?(error.localizedDescription)
         }
     }
@@ -225,6 +240,44 @@ final class TravelAlbumDetailViewModel {
         }
     }
 
+    /// 已购照片接口无数据时生成稳定的本地素材；真实接口一旦返回数据即不再使用。
+    private func applyPurchasedDemoMaterials() {
+        let demoItems: [(fileName: String, fileSize: Int, assetName: String, createdAt: String)] = [
+            ("IMG_0724_0001.jpeg", 2_684_928, "purchased_alpine_lake", "2026-07-24 11:25:18"),
+            ("IMG_0724_0002.jpeg", 3_215_360, "purchased_forest_waterfall", "2026-07-24 11:27:46"),
+            ("IMG_0724_0003.jpeg", 2_936_832, "purchased_grassland_path", "2026-07-24 11:31:09"),
+            ("IMG_0724_0004.jpeg", 3_481_600, "purchased_lakeside_flowers", "2026-07-24 11:34:22"),
+        ]
+        var materials = demoItems.enumerated().map { index, item in
+            TravelAlbumMaterial(
+                id: -((albumId * 10) + index + 1),
+                userEquityTravelId: albumId,
+                status: 2,
+                fileName: item.fileName,
+                fileType: 1,
+                fileUrl: TravelAlbumMaterial.bundledImageURL(assetName: item.assetName),
+                fileSize: item.fileSize,
+                coverUrl: TravelAlbumMaterial.bundledImageURL(assetName: item.assetName),
+                isPurchased: true,
+                createdAt: item.createdAt,
+                updatedAt: item.createdAt
+            )
+        }
+        switch sortOption {
+        case .createdAsc:
+            materials.sort { $0.createdAt < $1.createdAt }
+        case .createdDesc:
+            materials.sort { $0.createdAt > $1.createdAt }
+        case .fileNameAsc:
+            materials.sort { $0.fileName.localizedStandardCompare($1.fileName) == .orderedAscending }
+        case .fileNameDesc:
+            materials.sort { $0.fileName.localizedStandardCompare($1.fileName) == .orderedDescending }
+        }
+        self.materials = materials
+        canLoadMore = false
+        isUsingPurchasedDemoData = true
+    }
+
     private func notifyStateChange() {
         onStateChange?()
     }