package order

import (
	"enaklo-pos-be/internal/common/errors"
	"enaklo-pos-be/internal/common/logger"
	"enaklo-pos-be/internal/common/mycontext"
	"enaklo-pos-be/internal/constants"
	"enaklo-pos-be/internal/entity"
	"go.uber.org/zap"
	"math"
)

func (s *orderSvc) CreateOrderInquiry(ctx mycontext.Context,
	req *entity.OrderRequest) (*entity.OrderInquiryResponse, error) {
	productIDs, filteredItems, err := s.ValidateOrderItems(ctx, req.OrderItems)
	if err != nil {
		return nil, err
	}
	req.OrderItems = filteredItems

	productDetails, err := s.product.GetProductDetails(ctx, productIDs, req.PartnerID)
	if err != nil {
		logger.ContextLogger(ctx).Error("failed to get product details", zap.Error(err))
		return nil, err
	}

	orderCalculation, err := s.CalculateOrderTotals(ctx, req.OrderItems, productDetails, req.Source)
	if err != nil {
		return nil, err
	}

	customerID, err := s.customer.ResolveCustomer(ctx, &entity.CustomerResolutionRequest{
		ID:          req.CustomerID,
		Name:        req.CustomerName,
		Email:       req.CustomerEmail,
		PhoneNumber: req.CustomerPhoneNumber,
	})
	if err != nil {
		logger.ContextLogger(ctx).Error("failed to resolve customer", zap.Error(err))
		return nil, err
	}

	inquiry := entity.NewOrderInquiry(
		req.PartnerID,
		customerID,
		orderCalculation.Subtotal,
		orderCalculation.Tax,
		orderCalculation.Total,
		req.PaymentMethod,
		req.Source,
		req.CreatedBy,
		req.CustomerName,
		req.CustomerPhoneNumber,
		req.CustomerEmail,
		req.PaymentProvider,
		req.TableNumber,
		req.OrderType,
	)

	for _, item := range req.OrderItems {
		product := productDetails.Products[item.ProductID]
		inquiry.AddOrderItem(item, product)
	}

	savedInquiry, err := s.repo.CreateInquiry(ctx, inquiry)
	if err != nil {
		logger.ContextLogger(ctx).Error("failed to create order inquiry", zap.Error(err))
		return nil, err
	}

	token, err := s.crypt.GenerateJWTOrderInquiry(savedInquiry)
	if err != nil {
		logger.ContextLogger(ctx).Error("failed to generate token", zap.Error(err))
		return nil, err
	}

	return &entity.OrderInquiryResponse{
		OrderInquiry: savedInquiry,
		Token:        token,
	}, nil
}

func (s *orderSvc) ValidateOrderItems(ctx mycontext.Context, items []entity.OrderItemRequest) ([]int64, []entity.OrderItemRequest, error) {
	var productIDs []int64
	var filteredItems []entity.OrderItemRequest

	for _, item := range items {
		if item.Quantity <= 0 {
			continue
		}
		productIDs = append(productIDs, item.ProductID)
		filteredItems = append(filteredItems, item)
	}

	if len(productIDs) == 0 {
		return nil, nil, errors.ErrorBadRequest
	}

	return productIDs, filteredItems, nil
}

func (s *orderSvc) CalculateOrderTotals(
	ctx mycontext.Context,
	items []entity.OrderItemRequest,
	productDetails *entity.ProductDetails,
	source string,
) (*entity.OrderCalculation, error) {
	subtotal := 0.0

	for _, item := range items {
		product, ok := productDetails.Products[item.ProductID]
		if !ok {
			return nil, errors.NewError(errors.ErrorInvalidRequest.ErrorType(), "product not found")
		}
		subtotal += product.Price * float64(item.Quantity)
	}

	partnerID := ctx.GetPartnerID()
	setting, err := s.partnerSetting.GetSettings(ctx, *partnerID)

	if err != nil {
		return nil, errors.NewError(errors.ErrorInvalidRequest.ErrorType(), "failed to get partner settings")
	}

	tax := 0.0
	if setting.TaxEnabled {
		tax = (setting.TaxPercentage / 100) * subtotal
		tax = math.Round(tax/100) * 100
	}

	return &entity.OrderCalculation{
		Subtotal: subtotal,
		Tax:      tax,
		Total:    subtotal + tax,
	}, nil
}

func (s *orderSvc) validateInquiry(ctx mycontext.Context, token string) (*entity.OrderInquiry, error) {
	partnerID, inquiryID, err := s.crypt.ValidateJWTOrderInquiry(token)
	if err != nil {
		return nil, errors.NewError(errors.ErrorInvalidRequest.ErrorType(), "inquiry is not valid or expired")
	}

	if partnerID != *ctx.GetPartnerID() {
		return nil, errors.NewError(errors.ErrorInvalidRequest.ErrorType(), "invalid request")
	}

	inquiry, err := s.repo.FindInquiryByID(ctx, inquiryID)
	if err != nil {
		logger.ContextLogger(ctx).Error("error when finding inquiry", zap.Error(err))
		return nil, err
	}

	if inquiry.Status != constants.StatusPending {
		return nil, errors.NewError(errors.ErrorInvalidRequest.ErrorType(), "inquiry is no longer pending")
	}

	return inquiry, nil
}

func (s *orderSvc) GetOrderPaymentAnalysis(
	ctx mycontext.Context,
	partnerID int64,
	req entity.SearchRequest,
) (*entity.OrderPaymentAnalysis, error) {
	paymentBreakdown, err := s.repo.GetOrderPaymentMethodBreakdown(ctx, partnerID, req)
	if err != nil {
		return nil, err
	}

	var totalAmount float64
	var totalTransactions int64

	for _, breakdown := range paymentBreakdown {
		totalAmount += breakdown.TotalAmount
		totalTransactions += breakdown.TotalTransactions
	}

	return &entity.OrderPaymentAnalysis{
		TotalAmount:            totalAmount,
		TotalTransactions:      totalTransactions,
		PaymentMethodBreakdown: paymentBreakdown,
	}, nil
}

func (s *orderSvc) GetRevenueOverview(
	ctx mycontext.Context,
	partnerID int64,
	year int,
	granularity string,
	status string,
) ([]entity.RevenueOverviewItem, error) {
	req := entity.RevenueOverviewRequest{
		PartnerID:   partnerID,
		Year:        year,
		Granularity: granularity,
		Status:      status,
	}

	return s.repo.GetRevenueOverview(ctx, req)
}

func (s *orderSvc) GetSalesByCategory(
	ctx mycontext.Context,
	partnerID int64,
	period string,
	status string,
) ([]entity.SalesByCategoryItem, error) {
	req := entity.SalesByCategoryRequest{
		PartnerID: partnerID,
		Period:    period,
		Status:    status,
	}

	return s.repo.GetSalesByCategory(ctx, req)
}

func (s *orderSvc) GetPopularProducts(
	ctx mycontext.Context,
	partnerID int64,
	period string,
	status string,
	limit int,
	sortBy string,
) ([]entity.PopularProductItem, error) {
	req := entity.PopularProductsRequest{
		PartnerID: partnerID,
		Period:    period,
		Status:    status,
		Limit:     limit,
		SortBy:    sortBy,
	}

	return s.repo.GetPopularProducts(ctx, req)
}