package api

import (
	"encoding/json"
	"fmt"
	"io"
	"log/slog"
	"net/http"
	"strings"
	"time"
)

type EpicStruct struct {
	url      string
	baseUrl  string
	idPrefix string
	headers  map[string]string
	deals    DealsMap
	logger   *slog.Logger
}

func NewEpicApi(logger *slog.Logger) EpicStruct {
	epic := EpicStruct{
		url:      "https://store-site-backend-static-ipv4.ak.epicgames.com/freeGamesPromotions",
		baseUrl:  "https://store.epicgames.com/p/",
		idPrefix: "epic-",
		headers:  make(map[string]string),
		deals:    make(map[string]Deal),
		logger:   logger,
	}
	epic.headers["Accept-Language"] = "en"
	epic.headers["User-Agent"] = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:93.0) Gecko/20100101 Firefox/93.0"
	return epic
}

type epicApiBody struct {
	Data struct {
		Catalog struct {
			SearchStore struct {
				Elements []struct {
					Title                string `json:"title"`
					Id                   string `json:"id"`
					Description          string `json:"description"`
					OfferType            string `json:"offerType"`
					IsCodeRedemptionOnly bool   `json:"isCodeRedemptionOnly"`
					KeyImages            []struct {
						Type string `json:"type"`
						Url  string `json:"url"`
					} `json:"keyImages"`
					ProductSlug   string `json:"productSlug"`
					OfferMappings []struct {
						PageSlug string `json:"pageSlug"`
						PageType string `json:"pageType"`
					} `json:"offerMappings"`
					Price struct {
						TotalPrice struct {
							DiscountPrice int    `json:"discountPrice"`
							OriginalPrice int    `json:"originalPrice"`
							Discount      int    `json:"discount"`
							CurrencyCode  string `json:"currencyCode"`
						} `json:"totalPrice"`
					} `json:"price"`
					Promotions *struct {
						PromotionalOffers []struct {
							PromotionalOffers []struct {
								StartDate       time.Time `json:"startDate"`
								EndDate         time.Time `json:"endDate"`
								DiscountSetting struct {
									DiscountType       string `json:"discountType"`
									DiscountPercentage int    `json:"discountPercentage"`
								} `json:"discountSetting"`
							} `json:"promotionalOffers"`
						} `json:"promotionalOffers"`
					} `json:"promotions"`
				} `json:"elements"`
				Paging struct {
					Count int `json:"count"`
					Total int `json:"total"`
				} `json:"paging"`
			} `json:"searchStore"`
		} `json:"Catalog"`
	} `json:"data"`
}

func (e EpicStruct) Load() error {
	client := &http.Client{}
	req, err := http.NewRequest("GET", e.url, nil)
	if err != nil {
		return err
	}

	for key, value := range e.headers {
		req.Header.Set(key, value)
	}

	res, err := client.Do(req)
	if err != nil {
		return err
	}
	body, err := io.ReadAll(res.Body)
	if err != nil {
		return err
	}
	var data epicApiBody
	err = json.Unmarshal(body, &data)
	if err != nil {
		return err
	}

	for _, element := range data.Data.Catalog.SearchStore.Elements {
		if element.Promotions == nil ||
			len(element.Promotions.PromotionalOffers) == 0 ||
			len(element.Promotions.PromotionalOffers[0].PromotionalOffers) == 0 ||
			element.Promotions.PromotionalOffers[0].PromotionalOffers[0].DiscountSetting.DiscountPercentage != 0 {
			// no deal
			continue
		}
		productSlug := element.ProductSlug
		if len(element.OfferMappings) != 0 && productSlug == "" {
			productSlug = element.OfferMappings[0].PageSlug
		}
		if productSlug == "" {
			e.logger.Error("product slug not found", slog.String("title", element.Title))
			continue
		}

		image := ""
		for _, keyImage := range element.KeyImages {
			if keyImage.Type == "OfferImageWide" {
				image = keyImage.Url
			}
		}

		id := fmt.Sprintf("%v%v", e.idPrefix, element.Id)
		title := strings.TrimSpace(element.Title)
		url := fmt.Sprintf("%v%v", e.baseUrl, productSlug)

		e.deals[id] = Deal{
			Id:    id,
			Title: title,
			Url:   url,
			Image: image,
		}
	}

	return nil
}

func (e EpicStruct) Get() []Deal {
	var deals []Deal
	for _, deal := range e.deals {
		deals = append(deals, deal)
	}
	return deals
}