feat: create specific price system and adapt product queries

app/model/specificPrice.go

@@ -0,0 +1,30 @@
+package model
+
+import "time"
+
+type SpecificPrice struct {
+	ID                  uint64     `gorm:"primaryKey;autoIncrement" json:"id"`
+	Name                string     `gorm:"type:varchar(255);not null" json:"name"`
+	Scope               string     `gorm:"type:varchar(20);not null" json:"scope"`
+	ValidFrom           *time.Time `gorm:"null" json:"valid_from"`
+	ValidTill           *time.Time `gorm:"null" json:"valid_till"`
+	HasExpirationDate   bool       `gorm:"default:false" json:"has_expiration_date"`
+	ReductionType       string     `gorm:"type:enum('amount','percentage');not null" json:"reduction_type"`
+	Price               *float64   `gorm:"type:decimal(10,2);null" json:"price"`
+	CurrencyID          *uint64    `gorm:"column:b2b_id_currency;null" json:"currency_id"`
+	PercentageReduction *float64   `gorm:"type:decimal(5,2);null" json:"percentage_reduction"`
+	FromQuantity        uint32     `gorm:"default:1" json:"from_quantity"`
+	IsActive            bool       `gorm:"default:true" json:"is_active"`
+	CreatedAt           *time.Time `gorm:"null" json:"created_at"`
+	UpdatedAt           *time.Time `gorm:"null" json:"updated_at"`
+
+	ProductIDs          []uint64 `gorm:"-" json:"product_ids"`
+	CategoryIDs         []uint64 `gorm:"-" json:"category_ids"`
+	ProductAttributeIDs []uint64 `gorm:"-" json:"product_attribute_ids"`
+	CountryIDs          []uint64 `gorm:"-" json:"country_ids"`
+	CustomerIDs         []uint64 `gorm:"-" json:"customer_ids"`
+}
+
+func (SpecificPrice) TableName() string {
+	return "b2b_specific_price"
+}