refactor: remove repeating code etc

backend/internal/api/responses/response.go

@@ -0,0 +1,85 @@
+package responses
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+// Response is a standardized API response structure
+type Response struct {
+	Success bool        `json:"success"`
+	Data    interface{} `json:"data,omitempty"`
+	Error   *ErrorInfo  `json:"error,omitempty"`
+}
+
+// ErrorInfo contains detailed error information
+type ErrorInfo struct {
+	Code    string `json:"code"`
+	Message string `json:"message"`
+}
+
+// ErrorResponse codes
+const (
+	ErrorCodeValidation   = "VALIDATION_ERROR"
+	ErrorCodeNotFound     = "NOT_FOUND"
+	ErrorCodeUnauthorized = "UNAUTHORIZED"
+	ErrorCodeForbidden    = "FORBIDDEN"
+	ErrorCodeInternal     = "INTERNAL_ERROR"
+	ErrorCodeBadRequest   = "BAD_REQUEST"
+	ErrorCodeConflict     = "CONFLICT"
+)
+
+// SuccessResponse sends a successful response with data
+func SuccessResponse(c *gin.Context, statusCode int, data interface{}) {
+	c.JSON(statusCode, Response{
+		Success: true,
+		Data:    data,
+	})
+}
+
+// ErrorResponse sends an error response
+func ErrorResponse(c *gin.Context, statusCode int, errorCode string, message string) {
+	c.JSON(statusCode, Response{
+		Success: false,
+		Error: &ErrorInfo{
+			Code:    errorCode,
+			Message: message,
+		},
+	})
+}
+
+// BadRequestResponse sends a 400 Bad Request response
+func BadRequestResponse(c *gin.Context, message string) {
+	ErrorResponse(c, http.StatusBadRequest, ErrorCodeBadRequest, message)
+}
+
+// ValidationErrorResponse sends a 400 Bad Request response for validation errors
+func ValidationErrorResponse(c *gin.Context, message string) {
+	ErrorResponse(c, http.StatusBadRequest, ErrorCodeValidation, message)
+}
+
+// NotFoundResponse sends a 404 Not Found response
+func NotFoundResponse(c *gin.Context, message string) {
+	ErrorResponse(c, http.StatusNotFound, ErrorCodeNotFound, message)
+}
+
+// UnauthorizedResponse sends a 401 Unauthorized response
+func UnauthorizedResponse(c *gin.Context, message string) {
+	ErrorResponse(c, http.StatusUnauthorized, ErrorCodeUnauthorized, message)
+}
+
+// ForbiddenResponse sends a 403 Forbidden response
+func ForbiddenResponse(c *gin.Context, message string) {
+	ErrorResponse(c, http.StatusForbidden, ErrorCodeForbidden, message)
+}
+
+// InternalErrorResponse sends a 500 Internal Server Error response
+func InternalErrorResponse(c *gin.Context, message string) {
+	ErrorResponse(c, http.StatusInternalServerError, ErrorCodeInternal, message)
+}
+
+// ConflictResponse sends a 409 Conflict response
+func ConflictResponse(c *gin.Context, message string) {
+	ErrorResponse(c, http.StatusConflict, ErrorCodeConflict, message)
+}