Add LastDigits and binding to currency for cards

db/card.go

@@ -10,9 +10,12 @@ import (
 type Card struct {
 	gorm.Model
 	Name           string
+	LastDigits     string
 	Balance        uint64
 	HaveCreditLine bool
 	CreditLine     uint64
+	CurrencyID     uint
+	Currency       *Currency
 	UserID         uint
 	User           *User
 }
@@ -35,6 +38,7 @@ func (c *Card) SetUserID(id uint) {
 var (
 	ERROR_CARD_NAME_EMPTY      = errors.New("The 'Name' field for 'Card' cannot be empty")
 	ERROR_CARD_NAME_NOT_UNIQUE = errors.New("The 'Name' field for 'Card' have to be unique for user")
+	ERROR_CARD_CANT_FIND_CURR  = errors.New("The 'CurrencyID' field for 'Card' is invalid")
 )
 
 func (c *Card) BeforeSave(tx *gorm.DB) error {
@@ -50,6 +54,15 @@ func (c *Card) BeforeSave(tx *gorm.DB) error {
 	if c.ID != dup.ID && dup.ID != 0 {
 		return ERROR_CARD_NAME_NOT_UNIQUE
 	}
+	if c.CurrencyID != 0 {
+		var currency Currency
+		if err := tx.Find(&currency, c.CurrencyID).Error; err != nil {
+			return err
+		}
+		if currency.ID == 0 {
+			return ERROR_CARD_CANT_FIND_CURR
+		}
+	}
 
 	return nil
 }