fix: move implementation to "internal" package

internal/handler/error.go

@@ -0,0 +1,35 @@
+package handler
+
+import (
+	"errors"
+	"net/http"
+	"spend-sparrow/internal/db"
+	"spend-sparrow/internal/service"
+	"spend-sparrow/internal/utils"
+	"strings"
+)
+
+func handleError(w http.ResponseWriter, r *http.Request, err error) {
+	switch {
+	case errors.Is(err, service.ErrUnauthorized):
+		utils.TriggerToastWithStatus(w, r, "error", "You are not autorized to perform this operation.", http.StatusUnauthorized)
+		return
+	case errors.Is(err, service.ErrBadRequest):
+		utils.TriggerToastWithStatus(w, r, "error", extractErrorMessage(err), http.StatusBadRequest)
+		return
+	case errors.Is(err, db.ErrNotFound):
+		utils.TriggerToastWithStatus(w, r, "error", extractErrorMessage(err), http.StatusNotFound)
+		return
+	}
+
+	utils.TriggerToastWithStatus(w, r, "error", "Internal Server Error", http.StatusInternalServerError)
+}
+
+func extractErrorMessage(err error) string {
+	errMsg := err.Error()
+	if errMsg == "" {
+		return ""
+	}
+
+	return strings.SplitN(errMsg, ":", 2)[0]
+}