add order service

internal/services/order/order.go

@@ -0,0 +1,46 @@
+package order
+
+import (
+	"bytes"
+	"cake_crm/proto"
+	"errors"
+	"fmt"
+)
+
+type Service struct{}
+
+func NewService() *Service {
+	return &Service{}
+}
+
+func (s *Service) CreateOrderText(req *proto.OrderReq, items []*proto.CardItem) (string, error) {
+	buffer := bytes.Buffer{}
+	var orderAmount int64
+	buffer.WriteString(fmt.Sprintf("Заказ от:\n%s\n%s\n", req.Order.Name, req.Order.Phone))
+	buffer.WriteString("\n")
+	for _, item := range items {
+		buffer.WriteString(item.Name)
+		buffer.WriteString("\n")
+		unit, err := unitToText(item.Unit)
+		if err != nil {
+			return "", err
+		}
+		buffer.WriteString(fmt.Sprintf("Количество: %d%s\n", item.Count, unit))
+		orderAmount += item.Amount
+		buffer.WriteString(fmt.Sprintf("Сумма: %.00fр\n", float64(item.Amount)/100))
+		buffer.WriteString("\n")
+	}
+	buffer.WriteString("\n")
+	buffer.WriteString(fmt.Sprintf("ИТОГО: %.00fр\n", float64(orderAmount)/100))
+	return buffer.String(), nil
+}
+
+func unitToText(unit string) (string, error) {
+	switch unit {
+	case "kg":
+		return "кг", nil
+	case "piece":
+		return "шт", nil
+	}
+	return "", errors.New("unit not found")
+}