refactor: 调整渠道注册机制

internal/channel/factory.go

@@ -12,6 +12,32 @@ import (
 	"gorm.io/datatypes"
 )
 
+// channelConstructor defines the function signature for creating a new channel proxy.
+type channelConstructor func(f *Factory, group *models.Group) (ChannelProxy, error)
+
+var (
+	// channelRegistry holds the mapping from channel type string to its constructor.
+	channelRegistry = make(map[string]channelConstructor)
+)
+
+// Register adds a new channel constructor to the registry.
+// This function is intended to be called from the init() function of each channel implementation.
+func Register(channelType string, constructor channelConstructor) {
+	if _, exists := channelRegistry[channelType]; exists {
+		panic(fmt.Sprintf("channel type '%s' is already registered", channelType))
+	}
+	channelRegistry[channelType] = constructor
+}
+
+// GetChannels returns a slice of all registered channel type names.
+func GetChannels() []string {
+	supportedTypes := make([]string, 0, len(channelRegistry))
+	for t := range channelRegistry {
+		supportedTypes = append(supportedTypes, t)
+	}
+	return supportedTypes
+}
+
 // Factory is responsible for creating channel proxies.
 type Factory struct {
 	settingsManager *config.SystemSettingsManager
@@ -26,14 +52,11 @@ func NewFactory(settingsManager *config.SystemSettingsManager) *Factory {
 
 // GetChannel returns a channel proxy based on the group's channel type.
 func (f *Factory) GetChannel(group *models.Group) (ChannelProxy, error) {
-	switch group.ChannelType {
-	case "openai":
-		return f.NewOpenAIChannel(group)
-	case "gemini":
-		return f.NewGeminiChannel(group)
-	default:
+	constructor, ok := channelRegistry[group.ChannelType]
+	if !ok {
 		return nil, fmt.Errorf("unsupported channel type: %s", group.ChannelType)
 	}
+	return constructor(f, group)
 }
 
 // newBaseChannel is a helper function to create and configure a BaseChannel.
@@ -60,7 +83,7 @@ func (f *Factory) newBaseChannel(name string, upstreamsJSON datatypes.JSON, grou
 		}
 		weight := def.Weight
 		if weight <= 0 {
-			weight = 1 // Default weight to 1 if not specified or invalid
+			weight = 1
 		}
 		upstreamInfos = append(upstreamInfos, UpstreamInfo{URL: u, Weight: weight})
 	}