package checkout

import (
	"encoding/json"
	"sync"
	"time"

	"git.k6n.net/go-cart-actor/pkg/cart"
)

// CheckoutId is the same as CartId for simplicity
type CheckoutId = cart.CartId

type PickupPoint struct {
	DeliveryId uint32  `json:"deliveryId,omitempty"`
	Id         string  `json:"id"`
	Name       *string `json:"name,omitempty"`
	Address    *string `json:"address,omitempty"`
	City       *string `json:"city,omitempty"`
	Zip        *string `json:"zip,omitempty"`
	Country    *string `json:"country,omitempty"`
}

type CheckoutDelivery struct {
	Id          uint32       `json:"id"`
	Provider    string       `json:"provider"`
	Price       cart.Price   `json:"price"`
	Items       []uint32     `json:"items"`
	PickupPoint *PickupPoint `json:"pickupPoint,omitempty"`
}
type PaymentStatus string
type CheckoutPaymentStatus PaymentStatus

const (
	PaymentStatusPending           PaymentStatus         = "pending"
	PaymentStatusFailed            PaymentStatus         = "failed"
	PaymentStatusSuccess           PaymentStatus         = "success"
	CheckoutPaymentStatusPending   CheckoutPaymentStatus = "pending"
	CheckoutPaymentStatusFailed    CheckoutPaymentStatus = "failed"
	CheckoutPaymentStatusSuccess   CheckoutPaymentStatus = "success"
	CheckoutPaymentStatusCancelled CheckoutPaymentStatus = "partial"
)

type Payment struct {
	PaymentId          string           `json:"paymentId"`
	Status             PaymentStatus    `json:"status"`
	Amount             int64            `json:"amount"`
	Currency           string           `json:"currency"`
	Provider           string           `json:"provider,omitempty"`
	Method             *string          `json:"method,omitempty"`
	SessionData        *json.RawMessage `json:"sessionData,omitempty"`
	Events             []PaymentEvent   `json:"events,omitempty"`
	ProcessorReference *string          `json:"processorReference,omitempty"`
	StartedAt          *time.Time       `json:"startedAt,omitempty"`
	CompletedAt        *time.Time       `json:"completedAt,omitempty"`
}

type PaymentEvent struct {
	Name    string          `json:"name"`
	Success bool            `json:"success"`
	Data    json.RawMessage `json:"data"`
}

func (p *Payment) IsSettled() bool {
	if p == nil {
		return false
	}

	switch p.Status {
	case PaymentStatusSuccess:
		return true
	default:
		return false
	}
}

type ContactDetails struct {
	Email *string `json:"email,omitempty"`
	Phone *string `json:"phone,omitempty"`
	Name  *string `json:"name,omitempty"`
}

type ConfirmationStatus struct {
	Code         *string   `json:"code,omitempty"`
	ViewCount    int       `json:"viewCount"`
	LastViewedAt time.Time `json:"lastViewedAt"`
}

type CheckoutGrain struct {
	mu                     sync.RWMutex
	lastDeliveryId         uint32
	lastGiftcardId         uint32
	lastAccess             time.Time
	lastChange             time.Time
	Version                uint32              `json:"version"`
	Id                     CheckoutId          `json:"id"`
	CartId                 cart.CartId         `json:"cartId"`
	CartVersion            uint64              `json:"cartVersion"`
	CartState              *cart.CartGrain     `json:"cartState"` // snapshot of items
	CartTotalPrice         *cart.Price         `json:"cartTotalPrice"`
	OrderId                *string             `json:"orderId"`
	Deliveries             []*CheckoutDelivery `json:"deliveries,omitempty"`
	PaymentInProgress      uint16              `json:"paymentInProgress"`
	AmountInCentsRemaining int64               `json:"amountRemaining"`
	AmountInCentsStarted   int64               `json:"amountActive"`
	InventoryReserved      bool                `json:"inventoryReserved"`
	Confirmation           *ConfirmationStatus `json:"confirmationViewed,omitempty"`
	Payments               []*Payment          `json:"payments,omitempty"`
	ContactDetails         *ContactDetails     `json:"contactDetails,omitempty"`
}

func NewCheckoutGrain(id uint64, cartId cart.CartId, cartVersion uint64, ts time.Time, cartState *cart.CartGrain) *CheckoutGrain {
	r := &CheckoutGrain{
		lastDeliveryId: 0,
		lastGiftcardId: 0,
		lastAccess:     ts,
		lastChange:     ts,
		Id:             CheckoutId(id),
		CartId:         cartId,
		CartVersion:    cartVersion,
		Deliveries:     []*CheckoutDelivery{},
		Payments:       []*Payment{},
	}
	if cartState != nil {
		r.CartState = cartState
		r.CartTotalPrice = cartState.TotalPrice
	}
	return r
}

func (c *CheckoutGrain) GetId() uint64 {
	return uint64(c.Id)
}

func (c *CheckoutGrain) GetLastChange() time.Time {
	return c.lastChange
}

func (c *CheckoutGrain) GetLastAccess() time.Time {
	return c.lastAccess
}

func (c *CheckoutGrain) GetCurrentState() (*CheckoutGrain, error) {
	c.lastAccess = time.Now()
	return c, nil
}

func (c *CheckoutGrain) GetState() ([]byte, error) {
	return json.Marshal(c)
}

func (c *CheckoutGrain) FindPayment(paymentId string) (*Payment, bool) {
	if paymentId == "" {
		return nil, false
	}
	for _, payment := range c.Payments {
		if payment != nil && payment.PaymentId == paymentId {
			return payment, true
		}
	}
	return nil, false
}

func (c *CheckoutGrain) SettledPayments() []*Payment {
	if len(c.Payments) == 0 {
		return nil
	}
	settled := make([]*Payment, 0, len(c.Payments))
	for _, payment := range c.Payments {
		if payment != nil && payment.IsSettled() {
			settled = append(settled, payment)
		}
	}
	if len(settled) == 0 {
		return nil
	}
	return settled
}

func (c *CheckoutGrain) OpenPayments() []*Payment {
	if len(c.Payments) == 0 {
		return nil
	}
	pending := make([]*Payment, 0, len(c.Payments))
	for _, payment := range c.Payments {
		if payment == nil {
			continue
		}
		if !payment.IsSettled() {
			pending = append(pending, payment)
		}
	}
	if len(pending) == 0 {
		return nil
	}
	return pending
}