feat: 添加种子数据初始化功能，重构多个处理程序以简化错误响应和用户验证

internal/handler/helpers.go

@@ -0,0 +1,160 @@
+package handler
+
+import (
+	"carrotskin/internal/model"
+	"carrotskin/internal/types"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+// GetUserIDFromContext 从上下文获取用户ID，如果不存在返回未授权响应
+// 返回值: userID, ok (如果ok为false，已经发送了错误响应)
+func GetUserIDFromContext(c *gin.Context) (int64, bool) {
+	userID, exists := c.Get("user_id")
+	if !exists {
+		c.JSON(http.StatusUnauthorized, model.NewErrorResponse(
+			model.CodeUnauthorized,
+			model.MsgUnauthorized,
+			nil,
+		))
+		return 0, false
+	}
+	return userID.(int64), true
+}
+
+// UserToUserInfo 将 User 模型转换为 UserInfo 响应
+func UserToUserInfo(user *model.User) *types.UserInfo {
+	return &types.UserInfo{
+		ID:          user.ID,
+		Username:    user.Username,
+		Email:       user.Email,
+		Avatar:      user.Avatar,
+		Points:      user.Points,
+		Role:        user.Role,
+		Status:      user.Status,
+		LastLoginAt: user.LastLoginAt,
+		CreatedAt:   user.CreatedAt,
+		UpdatedAt:   user.UpdatedAt,
+	}
+}
+
+// ProfileToProfileInfo 将 Profile 模型转换为 ProfileInfo 响应
+func ProfileToProfileInfo(profile *model.Profile) *types.ProfileInfo {
+	return &types.ProfileInfo{
+		UUID:       profile.UUID,
+		UserID:     profile.UserID,
+		Name:       profile.Name,
+		SkinID:     profile.SkinID,
+		CapeID:     profile.CapeID,
+		IsActive:   profile.IsActive,
+		LastUsedAt: profile.LastUsedAt,
+		CreatedAt:  profile.CreatedAt,
+		UpdatedAt:  profile.UpdatedAt,
+	}
+}
+
+// ProfilesToProfileInfos 批量转换 Profile 模型为 ProfileInfo 响应
+func ProfilesToProfileInfos(profiles []*model.Profile) []*types.ProfileInfo {
+	result := make([]*types.ProfileInfo, 0, len(profiles))
+	for _, profile := range profiles {
+		result = append(result, ProfileToProfileInfo(profile))
+	}
+	return result
+}
+
+// TextureToTextureInfo 将 Texture 模型转换为 TextureInfo 响应
+func TextureToTextureInfo(texture *model.Texture) *types.TextureInfo {
+	return &types.TextureInfo{
+		ID:            texture.ID,
+		UploaderID:    texture.UploaderID,
+		Name:          texture.Name,
+		Description:   texture.Description,
+		Type:          types.TextureType(texture.Type),
+		URL:           texture.URL,
+		Hash:          texture.Hash,
+		Size:          texture.Size,
+		IsPublic:      texture.IsPublic,
+		DownloadCount: texture.DownloadCount,
+		FavoriteCount: texture.FavoriteCount,
+		IsSlim:        texture.IsSlim,
+		Status:        texture.Status,
+		CreatedAt:     texture.CreatedAt,
+		UpdatedAt:     texture.UpdatedAt,
+	}
+}
+
+// TexturesToTextureInfos 批量转换 Texture 模型为 TextureInfo 响应
+func TexturesToTextureInfos(textures []*model.Texture) []*types.TextureInfo {
+	result := make([]*types.TextureInfo, len(textures))
+	for i, texture := range textures {
+		result[i] = TextureToTextureInfo(texture)
+	}
+	return result
+}
+
+// RespondBadRequest 返回400错误响应
+func RespondBadRequest(c *gin.Context, message string, err error) {
+	c.JSON(http.StatusBadRequest, model.NewErrorResponse(
+		model.CodeBadRequest,
+		message,
+		err,
+	))
+}
+
+// RespondUnauthorized 返回401错误响应
+func RespondUnauthorized(c *gin.Context, message string) {
+	c.JSON(http.StatusUnauthorized, model.NewErrorResponse(
+		model.CodeUnauthorized,
+		message,
+		nil,
+	))
+}
+
+// RespondForbidden 返回403错误响应
+func RespondForbidden(c *gin.Context, message string) {
+	c.JSON(http.StatusForbidden, model.NewErrorResponse(
+		model.CodeForbidden,
+		message,
+		nil,
+	))
+}
+
+// RespondNotFound 返回404错误响应
+func RespondNotFound(c *gin.Context, message string) {
+	c.JSON(http.StatusNotFound, model.NewErrorResponse(
+		model.CodeNotFound,
+		message,
+		nil,
+	))
+}
+
+// RespondServerError 返回500错误响应
+func RespondServerError(c *gin.Context, message string, err error) {
+	c.JSON(http.StatusInternalServerError, model.NewErrorResponse(
+		model.CodeServerError,
+		message,
+		err,
+	))
+}
+
+// RespondSuccess 返回成功响应
+func RespondSuccess(c *gin.Context, data interface{}) {
+	c.JSON(http.StatusOK, model.NewSuccessResponse(data))
+}
+
+// RespondWithError 根据错误消息自动选择状态码
+func RespondWithError(c *gin.Context, err error) {
+	msg := err.Error()
+	switch msg {
+	case "档案不存在", "用户不存在", "材质不存在":
+		RespondNotFound(c, msg)
+	case "无权操作此档案", "无权操作此材质":
+		RespondForbidden(c, msg)
+	case "未授权":
+		RespondUnauthorized(c, msg)
+	default:
+		RespondServerError(c, msg, nil)
+	}
+}
+