fix(*): 模型选择 - 修复系统渠道 Logo 搜索与前台模型模式误判

backend/internal/service/task_creation.go

@@ -44,29 +44,9 @@ func (s *Service) CreateTask(userID string, req CreateTaskRequest) (*model.Task,
 	}
 
 	if !workflowProviderTask {
-		if frontendEnabled {
-			// 前台模型模式：必须有 logicalModelId
-			if logicalModelID == "" {
-				return nil, InvalidModelSelection("前台模型模式下必须指定 logicalModelId")
-			}
-			intent := ModelRequestIntentFromTaskInput(normalizedInput, taskType, req.Operation)
-			routed, err = s.ResolveLogicalModel(logicalModelID, intent)
-			if err != nil {
-				return nil, err
-			}
-			normalizedInput = applyRoutedProviderSelection(normalizedInput, routed)
-		} else {
-			// 系统渠道模型模式：禁止 logicalModelId
-			if logicalModelID != "" {
-				return nil, ModelCatalogMismatch("模型目录已更新，请重新选择")
-			}
-			// 自定义渠道没有系统 channelId；它会在后续由自定义渠道功能开关、
-			// 能力校验和 provider 配置校验共同处理，不能误报为“缺少系统渠道”。
-			if !taskInputUsesCustomChannel(normalizedInput) {
-				if err := s.validateSystemChannelModelSelection(normalizedInput); err != nil {
-					return nil, err
-				}
-			}
+		routed, normalizedInput, err = s.resolveTaskModelSelection(normalizedInput, logicalModelID, taskType, req.Operation, frontendEnabled)
+		if err != nil {
+			return nil, err
 		}
 	}
 
@@ -146,6 +126,34 @@ func (s *Service) CreateTask(userID string, req CreateTaskRequest) (*model.Task,
 	return taskForOutput(task), nil
 }
 
+// resolveTaskModelSelection 根据请求实际携带的模型选择决定路由方式。
+// 显式系统渠道请求不能被全局前台模型开关误判，但仍必须通过渠道、模型和价格校验。
+func (s *Service) resolveTaskModelSelection(input map[string]any, logicalModelID string, taskType string, operation string, frontendEnabled bool) (*RoutedModel, map[string]any, error) {
+	if frontendEnabled && !taskInputUsesSystemChannel(input) {
+		if logicalModelID == "" {
+			return nil, input, InvalidModelSelection("前台模型模式下必须指定 logicalModelId")
+		}
+		intent := ModelRequestIntentFromTaskInput(input, taskType, operation)
+		routed, err := s.ResolveLogicalModel(logicalModelID, intent)
+		if err != nil {
+			return nil, input, err
+		}
+		return routed, applyRoutedProviderSelection(input, routed), nil
+	}
+
+	if logicalModelID != "" {
+		return nil, input, ModelCatalogMismatch("模型目录已更新，请重新选择")
+	}
+	// 自定义渠道没有系统 channelId；它会在后续由自定义渠道功能开关、
+	// 能力校验和 provider 配置校验共同处理，不能误报为“缺少系统渠道”。
+	if !taskInputUsesCustomChannel(input) {
+		if err := s.validateSystemChannelModelSelection(input); err != nil {
+			return nil, input, err
+		}
+	}
+	return nil, input, nil
+}
+
 func applyRoutedProviderSelection(input map[string]any, routed *RoutedModel) map[string]any {
 	config, _ := input["config"].(map[string]any)
 	nextConfig := make(map[string]any, len(config)+2)
@@ -331,6 +339,15 @@ func taskInputUsesCustomChannel(input map[string]any) bool {
 	return strings.TrimSpace(baseURL) != "" && strings.TrimSpace(apiKey) != ""
 }
 
+func taskInputUsesSystemChannel(input map[string]any) bool {
+	config, ok := input["config"].(map[string]any)
+	if !ok {
+		return false
+	}
+	channelID, _ := config["channelId"].(string)
+	return strings.TrimSpace(channelID) != ""
+}
+
 func taskInputUsesWorkflowProvider(input map[string]any) bool {
 	config, ok := input["config"].(map[string]any)
 	if !ok {

backend/internal/service/task_creation_test.go

@@ -1,6 +1,15 @@
 package service
 
-import "testing"
+import (
+	"strings"
+	"testing"
+
+	"infinite-canvas/backend/internal/model"
+	"infinite-canvas/backend/internal/repository"
+
+	"gorm.io/driver/sqlite"
+	"gorm.io/gorm"
+)
 
 func TestTaskInputUsesWorkflowProvider(t *testing.T) {
 	tests := []struct {
@@ -26,3 +35,49 @@ func TestTaskInputUsesWorkflowProvider(t *testing.T) {
 		})
 	}
 }
+
+func TestResolveTaskModelSelectionAllowsExplicitSystemChannelWhenFrontendModelsEnabled(t *testing.T) {
+	db, err := gorm.Open(sqlite.Open("file:"+newID()+"?mode=memory&cache=shared"), &gorm.Config{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := db.AutoMigrate(&model.ModelChannel{}, &model.ChannelModel{}, &model.ChannelModelPriceTier{}); err != nil {
+		t.Fatal(err)
+	}
+	channel := model.ModelChannel{ID: "channel-1", Scope: model.ChannelScopeSystem, Enabled: true, Name: "Agnes"}
+	channelModel := model.ChannelModel{
+		ID: "channel-model-1", ChannelID: channel.ID, ModelKey: "agnes-video-2.5", Capability: "video",
+		Protocol: model.ChannelInterfaceNewAPIVideo, BillingMode: "per_second", PriceConfigured: true, Enabled: true,
+	}
+	if err := db.Create(&channel).Error; err != nil {
+		t.Fatal(err)
+	}
+	if err := db.Create(&channelModel).Error; err != nil {
+		t.Fatal(err)
+	}
+	input, err := normalizeTaskInput(map[string]any{
+		"mode":   "video",
+		"config": providerConfig{ChannelID: channel.ID, Model: channelModel.ModelKey, InterfaceType: string(channelModel.Protocol)},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	routed, resolvedInput, err := (&Service{repo: repository.New(db)}).resolveTaskModelSelection(input, "", "canvas_video", "", true)
+	if err != nil {
+		t.Fatalf("resolveTaskModelSelection() error = %v", err)
+	}
+	if routed != nil || resolvedInput["config"] == nil {
+		t.Fatalf("resolveTaskModelSelection() routed = %#v, input = %#v", routed, resolvedInput)
+	}
+}
+
+func TestResolveTaskModelSelectionStillRequiresLogicalModelWithoutExplicitSystemChannel(t *testing.T) {
+	_, _, err := (&Service{}).resolveTaskModelSelection(map[string]any{
+		"mode":   "video",
+		"config": map[string]any{"model": "agnes-video-2.5"},
+	}, "", "canvas_video", "", true)
+	if err == nil || !strings.Contains(err.Error(), "logicalModelId") {
+		t.Fatalf("resolveTaskModelSelection() error = %v, want logicalModelId validation", err)
+	}
+}