terminalShop/pkg/models/card.go

package models

import (
	"time"

	"gorm.io/gorm"
)

const cardStorageTTL = 180 * 24 * time.Hour

// Card represents a saved payment method linked to a Stripe token.
// The actual card details live on Stripe's servers — we only store
// a reference and display info (last 4 digits, brand).
type Card struct {
	ID               uint           `gorm:"primaryKey" json:"id"`
	UserID           uint           `gorm:"not null;index" json:"user_id"`
	StripePaymentID  string         `gorm:"size:255;not null" json:"-"`   // Stripe payment method or token ID
	Last4            string         `gorm:"size:4;not null" json:"last4"` // Last 4 digits for display
	Brand            string         `gorm:"size:50" json:"brand"`         // Visa, Mastercard, etc.
	ExpMonth         int            `gorm:"not null" json:"exp_month"`
	ExpYear          int            `gorm:"not null" json:"exp_year"`
	IsDefault        bool           `gorm:"default:false" json:"is_default"` // User's preferred card
	CreatedAt        time.Time      `json:"created_at"`
	UpdatedAt        time.Time      `json:"updated_at"`
	DeletedAt        gorm.DeletedAt `gorm:"index" json:"-"`
	LastUsedAt       *time.Time     `json:"last_used_at,omitempty"`
	StorageExpiresAt *time.Time     `gorm:"index" json:"storage_expires_at,omitempty"`

	// Associations
	User User `gorm:"foreignKey:UserID" json:"-"`
}

// TableName specifies the table name for the Card model.
func (Card) TableName() string {
	return "cards"
}

// CardStorageExpiresAt returns the inactivity expiration for a saved card
func CardStorageExpiresAt(now time.Time) *time.Time {
	expiresAt := now.Add(cardStorageTTL)
	return &expiresAt
}

// InitializeStorageTTL sets the initial retention deadline without marking
// the card as used for payment
func (c *Card) InitializeStorageTTL(now time.Time) {
	c.StorageExpiresAt = CardStorageExpiresAt(now)
}

// IsStorageExpired reports whether the saved card retention deadline elapsed
func (c *Card) IsStorageExpired(now time.Time) bool {
	return c.StorageExpiresAt != nil && !c.StorageExpiresAt.After(now)
}