topfans/backend/gateway/pkg/response/response.go

package response

import (
	"encoding/json"
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"
	"google.golang.org/grpc/codes"
)

// Response 统一响应格式
// 字段说明:
//   Code    — google.rpc.Code 数字(0=OK, 3=INVALID_ARGUMENT, 5=NOT_FOUND, 7=PERMISSION_DENIED, 8=RESOURCE_EXHAUSTED, 13=INTERNAL, 16=UNAUTHENTICATED)
//   Message — 错误信息(成功时为 "ok" 或自定义)
//   Data    — 业务数据(成功时填,失败时省略)
type Response struct {
	Code    uint32      `json:"code"`
	Message string      `json:"message"`
	Data    interface{} `json:"data,omitempty"`
}

// writeJSON 统一输出 JSON,并关闭 HTML 转义(避免将 & 转成 &,导致预签名 URL 失效)
func writeJSON(c *gin.Context, httpCode int, payload interface{}) {
	c.Status(httpCode)
	c.Header("Content-Type", "application/json; charset=utf-8")
	enc := json.NewEncoder(c.Writer)
	enc.SetEscapeHTML(false)
	_ = enc.Encode(payload)
}

// Success 业务成功响应(HTTP 200, body.code = 0)
func Success(c *gin.Context, data interface{}) {
	writeJSON(c, http.StatusOK, Response{
		Code:    uint32(codes.OK),
		Message: "ok",
		Data:    data,
	})
}

// SuccessWithMessage 业务成功响应(自定义消息)
func SuccessWithMessage(c *gin.Context, message string, data interface{}) {
	writeJSON(c, http.StatusOK, Response{
		Code:    uint32(codes.OK),
		Message: message,
		Data:    data,
	})
}

// Error transport error 响应 — 用于 controller 自身做参数校验 / 鉴权检查时的失败
//   - HTTP 状态码: 使用调用方传入的 httpCode(4xx/5xx)
//   - body.code: 同样使用 httpCode(transport error 用 HTTP 数字保持兼容,等待 controller 全部迁到 gRPC code 后改为 gRPC code)
//   - 调用 c.Abort() 告知 GRPCStatusInterceptor 保留原 HTTP 状态(不要强制改 200)
func Error(c *gin.Context, httpCode int, message string) {
	c.Abort()
	writeJSON(c, httpCode, Response{
		Code:    uint32(httpCode),
		Message: message,
	})
}

// ErrorWithCode 业务错误响应 — 用于 Dubbo 返回 gRPC code 时的失败
//   - 第一个参数 code: Dubbo 响应的 BaseResponse.code(gRPC code 数字)
//   - HTTP 强制 200,body.code = gRPC code(由 GRPCStatusInterceptor 兜底)
//   - 不调用 Abort() — 业务响应会被拦截器统一处理
func ErrorWithCode(c *gin.Context, code int, message string) {
	writeJSON(c, http.StatusOK, Response{
		Code:    uint32(code),
		Message: message,
	})
}

// BadRequest 400 错误请求(transport error)
func BadRequest(c *gin.Context, message string) {
	if message == "" {
		message = "请求参数错误"
	}
	Error(c, http.StatusBadRequest, message)
}

// Unauthorized 401 未授权(transport error)
func Unauthorized(c *gin.Context, message string) {
	if message == "" {
		message = "未授权，请先登录"
	}
	Error(c, http.StatusUnauthorized, message)
}

// Forbidden 403 禁止访问(transport error)
func Forbidden(c *gin.Context, message string) {
	if message == "" {
		message = "权限不足，禁止访问"
	}
	Error(c, http.StatusForbidden, message)
}

// NotFound 404 未找到(transport error)
func NotFound(c *gin.Context, message string) {
	if message == "" {
		message = "资源不存在"
	}
	Error(c, http.StatusNotFound, message)
}

// InternalError 500 服务器内部错误(transport error)
func InternalError(c *gin.Context, message string) {
	if message == "" {
		message = "服务器内部错误"
	}
	Error(c, http.StatusInternalServerError, message)
}

// CleanErrorMessage 清理错误消息,转换为中文友好提示
func CleanErrorMessage(err error) string {
	if err == nil {
		return ""
	}

	msg := err.Error()

	// 移除 gRPC 错误前缀
	if idx := strings.Index(msg, "code_"); idx >= 0 {
		if colonIdx := strings.Index(msg[idx:], ": "); colonIdx >= 0 {
			msg = msg[idx+colonIdx+2:]
		}
	}

	// 中英文错误映射
	errorMap := map[string]string{
		"user not found":                           "用户不存在",
		"user already exists":                      "该手机号已被注册",
		"invalid password":                         "密码错误",
		"invalid mobile format":                    "手机号格式不正确",
		"password too short":                       "密码长度不足，至少需要6位",
		"star not found":                           "明星不存在",
		"fan profile not found":                    "粉丝档案不存在",
		"invalid token":                            "Token无效",
		"token expired":                            "Token已过期",
		"user is inactive":                         "用户已被禁用",
		"maximum number of identities reached":     "已达到最大身份数量限制",
		"invalid star_id":                          "明星ID无效",
		"invalid user_id":                          "用户ID无效",
		"invalid nickname":                         "昵称格式不正确",
		"nickname too long":                        "昵称过长，最多20个字符",
		"nickname too short":                       "昵称过短，至少需要2个字符",
		"user info not found in Dubbo attachments": "请先登录",
		"missing or invalid authorization token":   "Token缺失或无效",
		"已达到最大好友数量限制":                   "已达到最大好友数量限制",
	}

	msgLower := strings.ToLower(msg)
	for eng, chn := range errorMap {
		if strings.Contains(msgLower, eng) {
			return chn
		}
	}

	// 如果没有匹配,返回原始消息
	return msg
}

// HandleError 统一处理错误并返回(根据 error message 字符串猜测类型 — 留给未来用 typed error 替换)
func HandleError(c *gin.Context, err error) {
	if err == nil {
		InternalError(c, "未知错误")
		return
	}

	msg := CleanErrorMessage(err)

	// 根据错误类型返回对应的 HTTP 状态码
	switch {
	case strings.Contains(msg, "not found") || strings.Contains(msg, "不存在"):
		NotFound(c, msg)
	case strings.Contains(msg, "unauthorized") ||
		strings.Contains(msg, "token") ||
		strings.Contains(msg, "请先登录"):
		Unauthorized(c, msg)
	case strings.Contains(msg, "invalid") ||
		strings.Contains(msg, "格式不正确") ||
		strings.Contains(msg, "过长") ||
		strings.Contains(msg, "过短"):
		BadRequest(c, msg)
	case strings.Contains(msg, "already exists") ||
		strings.Contains(msg, "已被注册"):
		Error(c, http.StatusConflict, msg)
	case strings.Contains(msg, "forbidden") ||
		strings.Contains(msg, "permission denied") ||
		strings.Contains(msg, "权限不足") ||
		strings.Contains(msg, "账号已被冻结") ||
		strings.Contains(msg, "账号已被封禁"):
		Forbidden(c, msg)
	default:
		InternalError(c, msg)
	}
}