package main

import (
	"encoding/json"
	"io/ioutil"
	"log"
	"net/http"
	"strconv"
	"time"
)

type Image struct {
	Size string `json:"size"`
	Href string `json:"#text"`
}

type AlbumInfo struct {
	Images   []Image `json:"image"`
	Mbid     string
	Name     string `json:"title"`
	Url      string
	Position `json:"@attr"`
	Artist   string
}

type Date struct {
	Date string `json:"#text"`
	Uts  string
}

func (d *Date) ToTime() time.Time {
	ts, _ := strconv.Atoi(d.Uts)
	return time.Unix(int64(ts), 0)
}

type PageAttrs struct {
	TotalPages string
	Total      string
	Page       string
	User       string
}

type ArtistInfo struct {
	Name string
	Mbid string
	Url  string
}

type Position struct {
	TrackNumber string `json:"position"`
}

type TrackInfo struct {
	Name      string
	Mbid      string
	Duration  string
	Artist    ArtistInfo
	Album     AlbumInfo
	PlayCount string
	Listeners string
}

type LovedTrack struct {
	Name   string
	Mbid   string
	Url    string
	Date   Date
	Artist ArtistInfo
	Images []Image
}

type Playing struct {
	NowPlaying string
}

type RecentTrack struct {
	Name   string
	Mbid   string
	Url    string
	Artist struct {
		Name string `json:"#text"`
		Mbid string
	}
	Album struct {
		Name string `json:"#text"`
		Mbid string
	}
	Images  []Image `json:"image"`
	Date    Date
	Playing `json:"@attr"`
}

func (app *App) LfmQuery(payload map[string]string) []byte {
	r, _ := http.NewRequest("GET", "http://ws.audioscrobbler.com/2.0/", nil)
	values := r.URL.Query()
	values.Add("api_key", app.Config.Lfm.ApiKey)
	values.Add("format", "json")
	for key, value := range payload {
		values.Add(key, value)
	}
	r.URL.RawQuery = values.Encode()
	resp, _ := http.DefaultClient.Do(r)
	body, _ := ioutil.ReadAll(resp.Body)
	resp.Body.Close()
	return body
}

func GetImage(images []Image, size string) string {
	for _, image := range images {
		if image.Size == size {
			return image.Href
		}
	}
	return "https://lastfm-img2.akamaized.net/i/u/64s/4128a6eb29f94943c9d206c08e625904.png"
}

func (app *App) AlbumInfo(artist, album string) AlbumInfo {
	r := app.LfmQuery(map[string]string{
		"method": "album.getInfo",
		"artist": artist,
		"album":  album,
	})
	var dst map[string]AlbumInfo
	json.Unmarshal(r, &dst)
	return dst["album"]
}

func (app *App) TrackInfo(artist, name string) TrackInfo {
	r := app.LfmQuery(map[string]string{
		"method":      "track.getInfo",
		"artist":      artist,
		"track":       name,
		"autocorrect": "1",
	})
	var dst map[string]TrackInfo
	json.Unmarshal(r, &dst)
	return dst["track"]
}

type RecentTracks struct {
	dst map[string]struct {
		Attrs  PageAttrs     `json:"@attr"`
		Tracks []RecentTrack `json:"track"`
	}
	payload map[string]string
	*App
}

func RecentTrackToScrobble(r *RecentTrack, s *Session) Scrobble {
	scrobble := Scrobble{
		Artist:     NewCorrectable(r.Artist.Name),
		Album:      NewCorrectable(r.Album.Name),
		TrackName:  NewCorrectable(r.Name),
		Mbid:       r.Mbid,
		Time:       r.Date.ToTime(),
		UserId:     s.UserId,
		SessionKey: s.Key,
		Image:      GetImage(r.Images, "medium"),
	}
	return scrobble
}

func NewRecentTracks(name string, from, to time.Time, app *App) *RecentTracks {
	rt := &RecentTracks{App: app}
	rt.payload = map[string]string{
		"method": "user.getRecentTracks",
		"limit":  "200",
		"user":   name,
		"to":     strconv.Itoa(int(to.Unix())),
	}
	if from.IsZero() {
		rt.payload["from"] = "0"
	} else {
		rt.payload["from"] = strconv.Itoa(int(from.Unix()))
	}
	return rt
}

func (rt *RecentTracks) Next() []RecentTrack {
	r := rt.App.LfmQuery(rt.payload)
	json.Unmarshal(r, &rt.dst)
	tracks := rt.dst["recenttracks"].Tracks
	if len(tracks) > 0 {
		d := tracks[len(tracks)-1].Date
		if d.Uts != "" && d.Uts != "0" {
			rt.payload["to"] = d.Uts
		}
	}
	return tracks
}

func (app *App) ImportRecentTracks(user *User) {
	s := &Session{
		UserId:        user.Id,
		Client:        "import",
		ClientVersion: "",
		Key:           randomToken(16),
		Protocol:      "1.2.1",
	}
	app.PutSession(s)
	i := app.NewImport(user.LfmName)
	rt := NewRecentTracks(user.LfmName, i.From, i.To, app)
	scrobbles := make([]Scrobble, 0, 200)
	for tracks := rt.Next(); len(tracks) > 0; tracks = rt.Next() {
		scrobbles = scrobbles[:0]
		for _, t := range tracks {
			if t.NowPlaying == "true" {
				continue
			}
			scrobble := RecentTrackToScrobble(&t, s)
			app.GetScrobbleSong(&scrobble)
			scrobbles = append(scrobbles, scrobble)
		}
		if len(scrobbles) == 0 {
			break
		}
		if err := app.PutScrobbles(scrobbles); err != nil {
			log.Println(err)
		}
		i.LastFetch = scrobbles[len(scrobbles)-1].Time
		i.Count += len(scrobbles)
		if err := app.SaveImport(i); err != nil {
			log.Println(err)
		}
	}
	i.Done = true
	if err := app.SaveImport(i); err != nil {
		log.Println(err)
	}
}

type LovedTracks struct {
	dst map[string]struct {
		Attrs  PageAttrs    `json:"@attr"`
		Tracks []LovedTrack `json:"track"`
	}
	payload map[string]string
	page    int
	done    bool
	*App
}

func NewLovedTracks(name string, app *App) *LovedTracks {
	lt := &LovedTracks{App: app, page: 1}
	lt.payload = map[string]string{
		"method": "user.getLovedTracks",
		"limit":  "200",
		"user":   name,
	}
	return lt
}

func (lt *LovedTracks) Next() []LovedTrack {
	if lt.done {
		return nil
	}
	lt.payload["page"] = strconv.Itoa(lt.page)
	r := lt.App.LfmQuery(lt.payload)
	json.Unmarshal(r, &lt.dst)
	root := lt.dst["lovedtracks"]
	totalPages, _ := strconv.Atoi(root.Attrs.TotalPages)
	if totalPages == lt.page {
		lt.done = true
	}
	lt.page++
	return root.Tracks
}

func (app *App) ImportLovedTracks(user *User) {
	s := &Session{
		UserId:        user.Id,
		Client:        "import",
		ClientVersion: "",
		Key:           randomToken(16),
		Protocol:      "1.2.1",
	}
	app.PutSession(s)
	ll, _ := app.LoveImportStats(user.LfmName)
	lt := NewLovedTracks(user.LfmName, app)
	ltracks := make([]LovedTrack, 0, 200)
	li := LoveImport{Count: 0, LfmName: user.LfmName}
	for tracks := lt.Next(); len(tracks) > 0; tracks = lt.Next() {
		ltracks = ltracks[:0]
		for _, t := range tracks {
			if t.Date.ToTime().Before(ll.Time) {
				break
			}
			ltracks = append(ltracks, t)
		}
		if err := app.InsertLovedTracks(ltracks, s); err != nil {
			log.Println(err)
			return
		}
		li.Count += len(ltracks)
	}
	if err := app.InsertLoveImport(&li); err != nil {
		log.Println(err)
	}
}

func (app *App) GetSong(s *Song) {
	if s.Album != "" || s.Mbid != "" {
		if app.GetSongId(s) != nil {
			if s.Image == "" {
				s.Image = GetImage(app.AlbumInfo(s.Artist, s.Album).Images,
					"medium")
			}
			if err := app.InsertSong(s); err != nil {
				log.Println(err)
			}
		}
	} else {
		t := app.TrackInfo(s.Artist, s.Name)
		s.Album = t.Album.Name
		s.Mbid = t.Mbid
		s.Image = GetImage(t.Album.Images, "medium")
		if app.GetSongId(s) != nil {
			app.InsertSong(s)
		}
	}
}