Refactor codebase

internal/interfaces/client.go

@@ -0,0 +1,54 @@
+// Package interfaces defines the core interfaces and shared structures for the CLI Proxy API server.
+// These interfaces provide a common contract for different components of the application,
+// such as AI service clients, API handlers, and data models.
+package interfaces
+
+import (
+	"context"
+	"sync"
+)
+
+// Client defines the interface that all AI API clients must implement.
+// This interface provides methods for interacting with various AI services
+// including sending messages, streaming responses, and managing authentication.
+type Client interface {
+	// Type returns the client type identifier (e.g., "gemini", "claude").
+	Type() string
+
+	// GetRequestMutex returns the mutex used to synchronize requests for this client.
+	// This ensures that only one request is processed at a time for quota management.
+	GetRequestMutex() *sync.Mutex
+
+	// GetUserAgent returns the User-Agent string used for HTTP requests.
+	GetUserAgent() string
+
+	// SendRawMessage sends a raw JSON message to the AI service without translation.
+	// This method is used when the request is already in the service's native format.
+	SendRawMessage(ctx context.Context, modelName string, rawJSON []byte, alt string) ([]byte, *ErrorMessage)
+
+	// SendRawMessageStream sends a raw JSON message and returns streaming responses.
+	// Similar to SendRawMessage but for streaming responses.
+	SendRawMessageStream(ctx context.Context, modelName string, rawJSON []byte, alt string) (<-chan []byte, <-chan *ErrorMessage)
+
+	// SendRawTokenCount sends a token count request to the AI service.
+	// This method is used to estimate the number of tokens in a given text.
+	SendRawTokenCount(ctx context.Context, modelName string, rawJSON []byte, alt string) ([]byte, *ErrorMessage)
+
+	// SaveTokenToFile saves the client's authentication token to a file.
+	// This is used for persisting authentication state between sessions.
+	SaveTokenToFile() error
+
+	// IsModelQuotaExceeded checks if the specified model has exceeded its quota.
+	// This helps with load balancing and automatic failover to alternative models.
+	IsModelQuotaExceeded(model string) bool
+
+	// GetEmail returns the email associated with the client's authentication.
+	// This is used for logging and identification purposes.
+	GetEmail() string
+
+	// CanProvideModel checks if the client can provide the specified model.
+	CanProvideModel(modelName string) bool
+
+	// Provider returns the name of the AI service provider (e.g., "gemini", "claude").
+	Provider() string
+}