yellowcab/scrape/lastfm.go

package scrape

import (
	"encoding/json"
	"errors"
	"fmt"
	"log"
	"net/http"
	"net/url"
	"os"
	"strconv"

	"github.com/joho/godotenv"
)

type lastfm struct {
	Name string
}

var LASTFM_KEY string

func init() {
	err := godotenv.Load()
	if err != nil {
		log.Fatal("Error loading .env file")
	}
	LASTFM_KEY = url.PathEscape(os.Getenv("LASTFM_KEY"))
}

type LastFmObject struct {
	Name string `json:"#text"`
	Id   string `json:"mbid"`
}

type LastFmTime struct {
	Unix  string `json:"uts"`
	Human string `json:"#text"`
}

type LastFmResponse struct {
	RecentTracks struct {
		Track []struct {
			Artist LastFmObject `json:"artist"`
			Album  LastFmObject `json:"album"`
			Name   string       `json:"name"`
			URL    string       `json:"url"`
			Cover  []struct {
				Size string `json:"size"`
				URL  string `json:"#text"`
			} `json:"image"`
			Time       *LastFmTime `json:"date"`
			Attributes *struct {
				NowPlaying string `json:"nowplaying"`
			} `json:"@attr,omitempty"`
		} `json:"track"`
	} `json:"recenttracks"`
}

func (s *lastfm) GetNowPlaying(username string) (response *ScrobblerResponse, err error) {
	encodedUsername := url.PathEscape(username)
	req, err := http.NewRequest("GET", fmt.Sprintf("https://ws.audioscrobbler.com/2.0/?method=user.getrecenttracks&user=%s&api_key=%s&format=json&limit=1", encodedUsername, LASTFM_KEY), nil)
	if err != nil {
		return
	}
	req.Header.Set("User-Agent", "Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0")
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return
	}
	defer resp.Body.Close()

	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
		err = errors.New("Request was unsuccessful, status code: " + strconv.Itoa(resp.StatusCode))
		return
	}

	var lastfmResponseBody LastFmResponse
	err = json.NewDecoder(resp.Body).Decode(&lastfmResponseBody)

	if len(lastfmResponseBody.RecentTracks.Track) <= 0 {
		err = errors.New("no listen history")
		return
	}

	var lastPlayedTimeString string
	lastPlayed := lastfmResponseBody.RecentTracks.Track[0]
	var lastPlayedTimeMs int64 = 0
	if lastPlayed.Attributes != nil && lastPlayed.Attributes.NowPlaying == "true" {
		lastPlayedTimeString = "live"
	} else if lastPlayed.Time != nil {
		lastPlayedTimeString = lastPlayed.Time.Human
		lastPlayedTimeMs, err = strconv.ParseInt(lastPlayed.Time.Unix, 10, 64)
		if err != nil {
			return
		}
		lastPlayedTimeMs *= 1000
	} else {
		fmt.Println(lastPlayed, *lastPlayed.Attributes)
		err = errors.New("LastFM API response is missing timestamp")
		return
	}

	trackURL := lastPlayed.URL
	track := Track{
		Name: lastPlayed.Name,
		URL:  &trackURL,
	}

	// TODO: implement stream URLs if possible?

	var album *Album
	if lastPlayed.Album.Name != "" {
		album = &Album{
			Name: lastPlayed.Album.Name,
			URL:  nil,
		}
	}

	var artist *Artist
	if lastPlayed.Artist.Name != "" {
		artist = &Artist{
			Name: lastPlayed.Artist.Name,
			URL:  nil,
		}
	}

	response = &ScrobblerResponse{
		FromScrobbler: FromScrobbler{
			Name:    s.Name,
			UserURL: fmt.Sprintf("https://www.last.fm/user/%s/", encodedUsername),
		},
		Track:        track,
		Artist:       artist,
		Album:        album,
		EstTimestamp: lastPlayedTimeString,
		TimestampMs:  lastPlayedTimeMs,
	}

	for _, cover := range lastPlayed.Cover {
		if cover.Size == "extralarge" && cover.URL != "" {
			response.Cover = &(cover.URL)
			break
		}
	}

	return
}

var Lastfm = lastfm{
	Name: "Last.fm",
}