package ebay

import (
	"context"
	"fmt"
	"net/http"
	"net/url"
	"time"
)

// BrowseService handles communication with the Browse API.
//
// eBay API docs: https://developer.ebay.com/api-docs/buy/browse/overview.html
type BrowseService service

// Valid values for the "buyingOptions" item field.
const (
	BrowseBuyingOptionAuction    = "AUCTION"
	BrowseBuyingOptionFixedPrice = "FIXED_PRICE"
)

// OptBrowseContextualLocation adds the header containing contextualLocation.
// It is strongly recommended that you use it when submitting Browse API methods.
//
// eBay API docs: https://developer.ebay.com/api-docs/buy/static/api-browse.html#Headers
func OptBrowseContextualLocation(country, zip string) func(*http.Request) {
	return func(req *http.Request) {
		const headerEndUserCtx = "X-EBAY-C-ENDUSERCTX"
		v := req.Header.Get(headerEndUserCtx)
		if len(v) > 0 {
			v += ","
		}
		v += "contextualLocation=" + url.QueryEscape(fmt.Sprintf("country=%s,zip=%s", country, zip))
		req.Header.Set(headerEndUserCtx, v)
	}
}

// LegacyItem represents the legacy representation of an eBay item.
type LegacyItem struct {
	ItemID             string `json:"itemId"`
	SellerItemRevision string `json:"sellerItemRevision"`
	Title              string `json:"title"`
	ShortDescription   string `json:"shortDescription"`
	Price              struct {
		Value    string `json:"value"`
		Currency string `json:"currency"`
	} `json:"price"`
	CategoryPath string `json:"categoryPath"`
	Condition    string `json:"condition"`
	ConditionID  string `json:"conditionId"`
	ItemLocation struct {
		City            string `json:"city"`
		StateOrProvince string `json:"stateOrProvince"`
		PostalCode      string `json:"postalCode"`
		Country         string `json:"country"`
	} `json:"itemLocation"`
	Image struct {
		ImageURL string `json:"imageUrl"`
	} `json:"image"`
	AdditionalImages []struct {
		ImageURL string `json:"imageUrl"`
	} `json:"additionalImages"`
	Brand       string    `json:"brand"`
	ItemEndDate time.Time `json:"itemEndDate"`
	Seller      struct {
		Username           string `json:"username"`
		FeedbackPercentage string `json:"feedbackPercentage"`
		FeedbackScore      int    `json:"feedbackScore"`
	} `json:"seller"`
	Gtin                    string `json:"gtin"`
	EstimatedAvailabilities []struct {
		DeliveryOptions             []string `json:"deliveryOptions"`
		EstimatedAvailabilityStatus string   `json:"estimatedAvailabilityStatus"`
		EstimatedAvailableQuantity  int      `json:"estimatedAvailableQuantity"`
		EstimatedSoldQuantity       int      `json:"estimatedSoldQuantity"`
	} `json:"estimatedAvailabilities"`
	ShippingOptions []struct {
		ShippingServiceCode string `json:"shippingServiceCode"`
		TrademarkSymbol     string `json:"trademarkSymbol"`
		ShippingCarrierCode string `json:"shippingCarrierCode"`
		Type                string `json:"type"`
		ShippingCost        struct {
			Value    string `json:"value"`
			Currency string `json:"currency"`
		} `json:"shippingCost"`
		QuantityUsedForEstimate       int       `json:"quantityUsedForEstimate"`
		MinEstimatedDeliveryDate      time.Time `json:"minEstimatedDeliveryDate"`
		MaxEstimatedDeliveryDate      time.Time `json:"maxEstimatedDeliveryDate"`
		ShipToLocationUsedForEstimate struct {
			PostalCode string `json:"postalCode"`
			Country    string `json:"country"`
		} `json:"shipToLocationUsedForEstimate"`
		AdditionalShippingCostPerUnit struct {
			Value    string `json:"value"`
			Currency string `json:"currency"`
		} `json:"additionalShippingCostPerUnit"`
		ShippingCostType string `json:"shippingCostType"`
	} `json:"shippingOptions"`
	ShipToLocations struct {
		RegionIncluded []struct {
			RegionName string `json:"regionName"`
			RegionType string `json:"regionType"`
		} `json:"regionIncluded"`
		RegionExcluded []struct {
			RegionName string `json:"regionName"`
			RegionType string `json:"regionType"`
		} `json:"regionExcluded"`
	} `json:"shipToLocations"`
	ReturnTerms struct {
		ReturnsAccepted         bool   `json:"returnsAccepted"`
		RefundMethod            string `json:"refundMethod"`
		ReturnMethod            string `json:"returnMethod"`
		ReturnShippingCostPayer string `json:"returnShippingCostPayer"`
		ReturnPeriod            struct {
			Value int    `json:"value"`
			Unit  string `json:"unit"`
		} `json:"returnPeriod"`
		RestockingFeePercentage string `json:"restockingFeePercentage"`
	} `json:"returnTerms"`
	Taxes []struct {
		TaxJurisdiction struct {
			Region struct {
				RegionName string `json:"regionName"`
				RegionType string `json:"regionType"`
			} `json:"region"`
			TaxJurisdictionID string `json:"taxJurisdictionId"`
		} `json:"taxJurisdiction"`
		TaxType                  string `json:"taxType"`
		TaxPercentage            string `json:"taxPercentage"`
		ShippingAndHandlingTaxed bool   `json:"shippingAndHandlingTaxed"`
		IncludedInPrice          bool   `json:"includedInPrice"`
	} `json:"taxes"`
	LocalizedAspects []struct {
		Type  string `json:"type"`
		Name  string `json:"name"`
		Value string `json:"value"`
	} `json:"localizedAspects"`
	PrimaryProductReviewRating struct {
		ReviewCount      int    `json:"reviewCount"`
		AverageRating    string `json:"averageRating"`
		RatingHistograms []struct {
			Rating string `json:"rating"`
			Count  int    `json:"count"`
		} `json:"ratingHistograms"`
	} `json:"primaryProductReviewRating"`
	TopRatedBuyingExperience bool     `json:"topRatedBuyingExperience"`
	BuyingOptions            []string `json:"buyingOptions"`
	ItemAffiliateWebURL      string   `json:"itemAffiliateWebUrl"`
	ItemWebURL               string   `json:"itemWebUrl"`
	Description              string   `json:"description"`
	EnabledForGuestCheckout  bool     `json:"enabledForGuestCheckout"`
	AdultOnly                bool     `json:"adultOnly"`
	CategoryID               string   `json:"categoryId"`
}

// GetItemByLegacyID retrieves an item by legacy ID.
// The itemID will be available in the "itemId" field:
// https://developer.ebay.com/api-docs/buy/static/api-browse.html#Legacy
//
// eBay API docs: https://developer.ebay.com/api-docs/buy/browse/resources/item/methods/getItemByLegacyId
func (s *BrowseService) GetItemByLegacyID(ctx context.Context, itemLegacyID string, opts ...Opt) (CompactItem, error) {
	u := fmt.Sprintf("buy/browse/v1/item/get_item_by_legacy_id?legacy_item_id=%s", itemLegacyID)
	req, err := s.client.NewRequest(http.MethodGet, u, nil, opts...)
	if err != nil {
		return CompactItem{}, err
	}
	var it CompactItem
	return it, s.client.Do(ctx, req, &it)
}

// CompactItem represents the "COMPACT" version of an eBay item.
type CompactItem struct {
	ItemID             string `json:"itemId"`
	SellerItemRevision string `json:"sellerItemRevision"`
	Price              struct {
		Value    string `json:"value"`
		Currency string `json:"currency"`
	} `json:"price"`
	EstimatedAvailabilities []struct {
		AvailabilityThresholdType   string `json:"availabilityThresholdType"`
		AvailabilityThreshold       int    `json:"availabilityThreshold"`
		EstimatedAvailabilityStatus string `json:"estimatedAvailabilityStatus"`
		EstimatedSoldQuantity       int    `json:"estimatedSoldQuantity"`
	} `json:"estimatedAvailabilities"`
	TopRatedBuyingExperience bool `json:"topRatedBuyingExperience"`
}

// GetCompactItem retrieves the compact version of a specific item.
//
// eBay API docs: https://developer.ebay.com/api-docs/buy/browse/resources/item/methods/getItem
func (s *BrowseService) GetCompactItem(ctx context.Context, itemID string, opts ...Opt) (CompactItem, error) {
	u := fmt.Sprintf("buy/browse/v1/item/%s?fieldgroups=COMPACT", itemID)
	req, err := s.client.NewRequest(http.MethodGet, u, nil, opts...)
	if err != nil {
		return CompactItem{}, err
	}
	var it CompactItem
	return it, s.client.Do(ctx, req, &it)
}

// Item represents an eBay item.
type Item struct {
	ItemID             string `json:"itemId"`
	SellerItemRevision string `json:"sellerItemRevision"`
	Title              string `json:"title"`
	Subtitle           string `json:"subtitle"`
	ShortDescription   string `json:"shortDescription"`
	Price              struct {
		Value    string `json:"value"`
		Currency string `json:"currency"`
	} `json:"price"`
	CategoryPath string `json:"categoryPath"`
	Condition    string `json:"condition"`
	ConditionID  string `json:"conditionId"`
	ItemLocation struct {
		City    string `json:"city"`
		Country string `json:"country"`
	} `json:"itemLocation"`
	Image struct {
		ImageURL string `json:"imageUrl"`
	} `json:"image"`
	AdditionalImages []struct {
		ImageURL string `json:"imageUrl"`
	} `json:"additionalImages"`
	MarketingPrice struct {
		OriginalPrice struct {
			Value    string `json:"value"`
			Currency string `json:"currency"`
		} `json:"originalPrice"`
		DiscountPercentage string `json:"discountPercentage"`
		DiscountAmount     struct {
			Value    string `json:"value"`
			Currency string `json:"currency"`
		} `json:"discountAmount"`
	} `json:"marketingPrice"`
	Color  string `json:"color"`
	Brand  string `json:"brand"`
	Seller struct {
		Username           string `json:"username"`
		FeedbackPercentage string `json:"feedbackPercentage"`
		FeedbackScore      int    `json:"feedbackScore"`
	} `json:"seller"`
	Gtin                    string `json:"gtin"`
	Mpn                     string `json:"mpn"`
	Epid                    string `json:"epid"`
	EstimatedAvailabilities []struct {
		DeliveryOptions             []string `json:"deliveryOptions"`
		AvailabilityThresholdType   string   `json:"availabilityThresholdType"`
		AvailabilityThreshold       int      `json:"availabilityThreshold"`
		EstimatedAvailabilityStatus string   `json:"estimatedAvailabilityStatus"`
		EstimatedSoldQuantity       int      `json:"estimatedSoldQuantity"`
	} `json:"estimatedAvailabilities"`
	ShippingOptions []struct {
		ShippingServiceCode string `json:"shippingServiceCode"`
		Type                string `json:"type"`
		ShippingCost        struct {
			Value    string `json:"value"`
			Currency string `json:"currency"`
		} `json:"shippingCost"`
		QuantityUsedForEstimate       int       `json:"quantityUsedForEstimate"`
		MinEstimatedDeliveryDate      time.Time `json:"minEstimatedDeliveryDate"`
		MaxEstimatedDeliveryDate      time.Time `json:"maxEstimatedDeliveryDate"`
		ShipToLocationUsedForEstimate struct {
			Country string `json:"country"`
		} `json:"shipToLocationUsedForEstimate"`
		AdditionalShippingCostPerUnit struct {
			Value    string `json:"value"`
			Currency string `json:"currency"`
		} `json:"additionalShippingCostPerUnit"`
		ShippingCostType string `json:"shippingCostType"`
	} `json:"shippingOptions"`
	ShipToLocations struct {
		RegionIncluded []struct {
			RegionName string `json:"regionName"`
			RegionType string `json:"regionType"`
		} `json:"regionIncluded"`
		RegionExcluded []struct {
			RegionName string `json:"regionName"`
			RegionType string `json:"regionType"`
		} `json:"regionExcluded"`
	} `json:"shipToLocations"`
	ReturnTerms struct {
		ReturnsAccepted         bool   `json:"returnsAccepted"`
		RefundMethod            string `json:"refundMethod"`
		ReturnMethod            string `json:"returnMethod"`
		ReturnShippingCostPayer string `json:"returnShippingCostPayer"`
		ReturnPeriod            struct {
			Value int    `json:"value"`
			Unit  string `json:"unit"`
		} `json:"returnPeriod"`
		ReturnInstructions      string `json:"returnInstructions"`
		RestockingFeePercentage string `json:"restockingFeePercentage"`
	} `json:"returnTerms"`
	Taxes []struct {
		TaxJurisdiction struct {
			Region struct {
				RegionName string `json:"regionName"`
				RegionType string `json:"regionType"`
			} `json:"region"`
			TaxJurisdictionID string `json:"taxJurisdictionId"`
		} `json:"taxJurisdiction"`
		TaxType                  string `json:"taxType"`
		TaxPercentage            string `json:"taxPercentage"`
		ShippingAndHandlingTaxed bool   `json:"shippingAndHandlingTaxed"`
		IncludedInPrice          bool   `json:"includedInPrice"`
	} `json:"taxes"`
	LocalizedAspects []struct {
		Type  string `json:"type"`
		Name  string `json:"name"`
		Value string `json:"value"`
	} `json:"localizedAspects"`
	QuantityLimitPerBuyer      int `json:"quantityLimitPerBuyer"`
	PrimaryProductReviewRating struct {
		ReviewCount      int    `json:"reviewCount"`
		AverageRating    string `json:"averageRating"`
		RatingHistograms []struct {
			Rating string `json:"rating"`
			Count  int    `json:"count"`
		} `json:"ratingHistograms"`
	} `json:"primaryProductReviewRating"`
	TopRatedBuyingExperience bool     `json:"topRatedBuyingExperience"`
	BuyingOptions            []string `json:"buyingOptions"`
	ItemAffiliateWebURL      string   `json:"itemAffiliateWebUrl"`
	ItemWebURL               string   `json:"itemWebUrl"`
	Description              string   `json:"description"`
	Product                  struct {
		AspectGroups []struct {
			LocalizedGroupName string `json:"localizedGroupName"`
			Aspects            []struct {
				LocalizedName   string   `json:"localizedName"`
				LocalizedValues []string `json:"localizedValues"`
			} `json:"aspects"`
		} `json:"aspectGroups"`
		Title       string `json:"title"`
		Description string `json:"description"`
		Image       struct {
			ImageURL string `json:"imageUrl"`
		} `json:"image"`
		Gtins                       []string `json:"gtins"`
		Brand                       string   `json:"brand"`
		Mpns                        []string `json:"mpns"`
		AdditionalProductIdentities []struct {
			ProductIdentity []struct {
				IdentifierType  string `json:"identifierType"`
				IdentifierValue string `json:"identifierValue"`
			} `json:"productIdentity"`
		} `json:"additionalProductIdentities"`
	} `json:"product"`
	EnabledForGuestCheckout bool   `json:"enabledForGuestCheckout"`
	AdultOnly               bool   `json:"adultOnly"`
	CategoryID              string `json:"categoryId"`

	// Fields not present in the json sample provided by eBay:
	ItemEndDate       time.Time `json:"itemEndDate"`
	MinimumPriceToBid struct {
		Currency string `json:"currency"`
		Value    string `json:"value"`
	} `json:"minimumPriceToBid"`
	CurrentBidPrice struct {
		Currency string `json:"currency"`
		Value    string `json:"value"`
	} `json:"currentBidPrice"`
	UniqueBidderCount int `json:"uniqueBidderCount"`
}

// GetItem retrieves the details of a specific item.
//
// eBay API docs: https://developer.ebay.com/api-docs/buy/browse/resources/item/methods/getItem
func (s *BrowseService) GetItem(ctx context.Context, itemID string, opts ...Opt) (Item, error) {
	u := fmt.Sprintf("buy/browse/v1/item/%s?fieldgroups=PRODUCT", itemID)
	req, err := s.client.NewRequest(http.MethodGet, u, nil, opts...)
	if err != nil {
		return Item{}, err
	}
	var it Item
	return it, s.client.Do(ctx, req, &it)
}