package reddit

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

type redditResponse struct {
	Kind string `json:"kind"`
	Data struct {
		After     string `json:"after"`
		Dist      int    `json:"dist"`
		ModHash   string `json:"modhash"`
		GeoFilter string `json:"geo_filter"`
		Children  []struct {
			Kind string `json:"kind"`
			Data struct {
				ApprovedAtUtc       interface{} `json:"approved_at_utc"`
				Subreddit           string      `json:"subreddit"`
				SelfText            string      `json:"selftext"`
				Url                 string      `json:"url"`
				UrlOverriddenByDest string      `json:"url_overridden_by_dest"`
				MediaMetadata       map[string]struct {
					Status string `json:"status"`
					Id     string `json:"id"`
					E      string `json:"e"`
					M      string `json:"m"`
					S      struct {
						U string `json:"u"`
						X int    `json:"x"`
						Y int    `json:"y"`
					} `json:"s"`
					P []struct {
						U string `json:"u"`
						X int    `json:"x"`
						Y int    `json:"y"`
					} `json:"p"`
				} `json:"media_metadata"`
				Preview struct {
					Enabled bool `json:"enabled"`
					Images  []struct {
						Source struct {
							Url    string `json:"url"`
							Width  int    `json:"width"`
							Height int    `json:"height"`
						} `json:"source"`
					} `json:"images"`
				} `json:"preview"`
			} `json:"data"`
		} `json:"children"`
	} `json:"data"`
}

func GetLatestImage(httpGet func(url string) (*http.Response, error)) (string, error) {

	response, err := httpGet("https://www.reddit.com/r/wallpaper/.json")
	if err != nil {
		return "", err
	}
	defer func(Body io.ReadCloser) {
		_ = Body.Close()
	}(response.Body)

	if response.StatusCode != http.StatusOK {
		return "", fmt.Errorf("error fetching reddit data: %s", response.Status)
	}

	jsonBytes, err := io.ReadAll(response.Body)

	redditData := redditResponse{}
	err = json.Unmarshal(jsonBytes, &redditData)
	if err != nil {
		return "", err
	}

	index := 1
	url := redditData.Data.Children[index].Data.UrlOverriddenByDest

	for strings.Contains(url, "gallery") {
		index++
		url = redditData.Data.Children[index].Data.UrlOverriddenByDest
	}

	return url, nil
}