init

backend/internal/socialrating/handler.go

@@ -0,0 +1,99 @@
+package socialrating
+
+import (
+	"errors"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"gorm.io/gorm"
+
+	"social-raiting.nekiiinkognito.ru/internal/models"
+)
+
+type Handler struct {
+	Service Service
+}
+
+type ChangeRequest struct {
+	TargetUserID uint   `json:"targetUserId" binding:"required"`
+	Amount       int    `json:"amount"`
+	Reason       string `json:"reason"`
+	Source       string `json:"source"`
+}
+
+type ChangeResponse struct {
+	Operation     models.SocialRatingOperation `json:"operation"`
+	CurrentRating models.UserSocialRating      `json:"currentRating"`
+}
+
+func NewHandler(service Service) Handler {
+	return Handler{Service: service}
+}
+
+func (h Handler) Increase(ctx *gin.Context) {
+	h.applySignedChange(ctx, "increase", 1)
+}
+
+func (h Handler) Decrease(ctx *gin.Context) {
+	h.applySignedChange(ctx, "decrease", -1)
+}
+
+func (h Handler) applySignedChange(ctx *gin.Context, operationType string, direction int) {
+	var req ChangeRequest
+	if err := ctx.ShouldBindJSON(&req); err != nil {
+		ctx.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	actorUserID, ok := getActorUserID(ctx)
+	if !ok {
+		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "missing user context"})
+		return
+	}
+
+	amount := req.Amount
+	if amount == 0 {
+		amount = 1
+	}
+	if amount < 0 {
+		ctx.JSON(http.StatusBadRequest, gin.H{"error": "amount must be greater than zero"})
+		return
+	}
+
+	operation, currentRating, err := h.Service.ApplyChange(ChangeInput{
+		TargetUserID:  req.TargetUserID,
+		ActorUserID:   &actorUserID,
+		Delta:         amount * direction,
+		OperationType: operationType,
+		Reason:        req.Reason,
+		Source:        req.Source,
+	})
+	if err != nil {
+		handleApplyChangeError(ctx, err)
+		return
+	}
+
+	ctx.JSON(http.StatusOK, ChangeResponse{
+		Operation:     operation,
+		CurrentRating: currentRating,
+	})
+}
+
+func getActorUserID(ctx *gin.Context) (uint, bool) {
+	value, exists := ctx.Get("userID")
+	if !exists {
+		return 0, false
+	}
+
+	userID, ok := value.(uint)
+	return userID, ok
+}
+
+func handleApplyChangeError(ctx *gin.Context, err error) {
+	switch {
+	case errors.Is(err, gorm.ErrRecordNotFound):
+		ctx.JSON(http.StatusNotFound, gin.H{"error": "user not found"})
+	default:
+		ctx.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+	}
+}

backend/internal/socialrating/service.go

@@ -0,0 +1,97 @@
+package socialrating
+
+import (
+	"errors"
+	"strings"
+
+	"gorm.io/gorm"
+
+	"social-raiting.nekiiinkognito.ru/internal/models"
+)
+
+type Service struct {
+	DB *gorm.DB
+}
+
+type ChangeInput struct {
+	TargetUserID  uint
+	ActorUserID   *uint
+	Delta         int
+	OperationType string
+	Reason        string
+	Source        string
+}
+
+func NewService(db *gorm.DB) Service {
+	return Service{DB: db}
+}
+
+func (s Service) ApplyChange(input ChangeInput) (models.SocialRatingOperation, models.UserSocialRating, error) {
+	var operation models.SocialRatingOperation
+	var currentRating models.UserSocialRating
+
+	if err := validateChangeInput(input); err != nil {
+		return operation, currentRating, err
+	}
+
+	err := s.DB.Transaction(func(tx *gorm.DB) error {
+		if err := ensureUserExists(tx, input.TargetUserID); err != nil {
+			return err
+		}
+
+		if input.ActorUserID != nil {
+			if err := ensureUserExists(tx, *input.ActorUserID); err != nil {
+				return err
+			}
+		}
+
+		currentRating = models.UserSocialRating{UserID: input.TargetUserID}
+		if err := tx.FirstOrCreate(&currentRating, models.UserSocialRating{
+			UserID: input.TargetUserID,
+		}).Error; err != nil {
+			return err
+		}
+
+		// Social rating is allowed to go below zero, so no lower bound is applied here.
+		currentRating.Score += input.Delta
+
+		operation = models.SocialRatingOperation{
+			TargetUserID:  input.TargetUserID,
+			ActorUserID:   input.ActorUserID,
+			Delta:         input.Delta,
+			OperationType: strings.TrimSpace(input.OperationType),
+			Reason:        strings.TrimSpace(input.Reason),
+			Source:        strings.TrimSpace(input.Source),
+			BalanceAfter:  currentRating.Score,
+		}
+		if err := tx.Create(&operation).Error; err != nil {
+			return err
+		}
+
+		currentRating.LastOperationID = &operation.ID
+		return tx.Save(&currentRating).Error
+	})
+
+	return operation, currentRating, err
+}
+
+func validateChangeInput(input ChangeInput) error {
+	if input.TargetUserID == 0 {
+		return errors.New("target user id is required")
+	}
+
+	if strings.TrimSpace(input.OperationType) == "" {
+		return errors.New("operation type is required")
+	}
+
+	if input.Delta == 0 {
+		return errors.New("delta must not be zero")
+	}
+
+	return nil
+}
+
+func ensureUserExists(tx *gorm.DB, userID uint) error {
+	var user models.User
+	return tx.First(&user, "id = ?", userID).Error
+}