package main

import (
	"database/sql"
	"encoding/xml"
	"log"
	"time"
)

type Scrobble struct {
	Artist      Correctable `xml:"artist" json:"artist"`
	AlbumArtist Correctable `xml:"albumArtist" json:"albumArtist"`
	TrackName   Correctable `xml:"track" json:"track"`
	Album       Correctable `xml:"album" json:"album"`
	TrackNumber int         `xml:"-" json:"-"`
	Duration    int         `xml:"-" json:"-"`
	Time        time.Time   `xml:"timestamp" json:"timestamp,string"`
	Chosen      bool        `xml:"-" json:"-"`
	Mbid        string      `xml:"-" json:"-"`
	SongId      int
	SessionKey  string `xml:"-" json:"-"`
	UserId      int
	Image       string
}

type Session struct {
	XMLName       xml.Name `json:"-" xml:"session"`
	User          string   `json:"name" xml:"name"`
	Key           string   `json:"key" xml:"key"`
	UserId        int
	Client        string
	ClientVersion string
	Protocol      string
	Created       time.Time
	Subscriber    int64 `json:"subscriber" xml:"subscriber"`
}

type Song struct {
	Id          int
	Artist      string
	Album       string
	Name        string
	TrackNumber int
	Duration    int
	Mbid        string
	Image       string
}

type Import struct {
	LfmName   string
	From      time.Time
	To        time.Time
	LastFetch time.Time
	Done      bool
	Count     int
}

type LoveImport struct {
	LfmName string
	Time    time.Time
	Count   int
}

type DataStore interface {
	PutSession(*Session) error
	GetSession(key string) (*Session, error)
	PutScrobbles([]Scrobble) error
	PutNowPlaying(s Scrobble) error
	NowPlaying(userId int) *Scrobble
	RecentScrobbles(userId int) []*Scrobble

	GetSongId(s *Song) error
	InsertSong(s *Song) error

	GetScrobblingUser(lfmName string) (int, string, error)
	GetUser(u *User) error
	InsertUser(u *User) error
	SaveUser(u *User) error

	SaveImport(i *Import) error
	InsertImport(i *Import) error
	NewImport(name string) *Import
	ImportStats(name string) (*Import, error)

	InsertLoveImport(i *LoveImport) error
	LoveImportStats(name string) (*LoveImport, error)

	InsertLovedTracks([]LovedTrack, *Session) error

	InsertUserSession(s *UserSession) error
	Api
}

type SqlStore struct {
	*sql.DB
}

func (store *SqlStore) PutSession(s *Session) error {
	query := `
	INSERT INTO scrobbling_sessions (user_id, session_key, client, client_version, protocol)
	VALUES ($1, $2, $3, $4, $5)`
	_, err := store.Exec(query, s.UserId, s.Key, s.Client, s.ClientVersion, s.Protocol)
	return err
}

func (store *SqlStore) GetSession(key string) (*Session, error) {
	query := `
	SELECT user_id, session_key, client, client_version, protocol, created
	FROM scrobbling_sessions WHERE session_key = $1`
	row := store.QueryRow(query, key)
	s := new(Session)
	err := row.Scan(&s.UserId, &s.Key, &s.Client, &s.ClientVersion, &s.Protocol,
		&s.Created)
	return s, err
}

func (store *SqlStore) GetScrobblingUser(lfmName string) (int, string, error) {
	var password string
	var userId int
	row := store.QueryRow("SELECT user_id, lfm_password FROM users WHERE lfm_name = $1",
		lfmName)
	err := row.Scan(&userId, &password)
	return userId, password, err
}

func (store *SqlStore) PutScrobbles(scrobbles []Scrobble) error {
	tx, err := store.Begin()
	if err != nil {
		return err
	}
	query := `
	INSERT INTO scrobbles
	(artist, album_artist, track_name, album, track_number, duration, time,
	chosen, mbid, song_id, session_key, user_id)
	VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)`
	st, err := tx.Prepare(query)
	if err != nil {
		return err
	}

	for _, s := range scrobbles {
		_, err = st.Exec(s.Artist, s.AlbumArtist, s.TrackName, s.Album,
			s.TrackNumber, s.Duration, s.Time, s.Chosen, s.Mbid, s.SongId,
			s.SessionKey, s.UserId)
		if err != nil {
			tx.Rollback()
			return err
		}
	}
	return tx.Commit()
}

func (store *SqlStore) PutNowPlaying(s Scrobble) error {
	query := `
	INSERT INTO now_playing
	(artist, album_artist, track_name, album, track_number, duration, 
	mbid, song_id, session_key, user_id)
	VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10)
	ON CONFLICT (user_id) DO UPDATE
	set artist=$1, album_artist=$2, track_name=$3, album=$4, track_number=$5,
	duration=$6, mbid=$7, song_id=$8, session_key=$9, user_id=$10,
	received=current_timestamp`

	_, err := store.Exec(query, s.Artist, s.AlbumArtist, s.TrackName, s.Album,
		s.TrackNumber, s.Duration, s.Mbid, s.SongId, s.SessionKey, s.UserId)
	return err
}

func (store *SqlStore) RecentScrobbles(userId int) []*Scrobble {
	scrobbles := make([]*Scrobble, 0, 10)
	query := `
	SELECT s.artist, s.album, s.track_name, s.time, songs.image
	FROM scrobbles s
	LEFT JOIN songs ON songs.song_id = s.song_id
	WHERE user_id=$1 ORDER BY time DESC LIMIT 10`
	rows, err := store.Query(query, userId)
	if err != nil {
		log.Println(err)
		return scrobbles
	}
	defer rows.Close()

	for rows.Next() {
		scrobble := new(Scrobble)
		rows.Scan(&scrobble.Artist.Name, &scrobble.Album.Name,
			&scrobble.TrackName.Name, &scrobble.Time, &scrobble.Image)
		scrobbles = append(scrobbles, scrobble)
	}
	return scrobbles
}

func (store *SqlStore) NowPlaying(userId int) *Scrobble {
	scrobble := new(Scrobble)
	query := `
	SELECT s.artist, s.album, s.track_name, s.received, songs.image, s.duration
	FROM now_playing s
	LEFT JOIN songs ON songs.song_id = s.song_id
	WHERE user_id=$1`
	row := store.QueryRow(query, userId)
	row.Scan(&scrobble.Artist.Name, &scrobble.Album.Name,
		&scrobble.TrackName.Name, &scrobble.Time, &scrobble.Image,
		&scrobble.Duration)
	return scrobble
}

func (store *SqlStore) GetSongId(s *Song) error {
	var query string
	if s.Mbid != "" {
		query = `SELECT song_id FROM songs WHERE mbid=$1`
		row := store.QueryRow(query, s.Mbid)
		return row.Scan(&s.Id)
	} else {
		query = `
		SELECT song_id FROM songs
		WHERE artist=$1 AND album=$2 AND name=$3`
		row := store.QueryRow(query, s.Artist, s.Album, s.Name)
		return row.Scan(&s.Id)
	}
}

func (store *SqlStore) InsertSong(s *Song) error {
	query := `
	INSERT INTO songs (artist, album, name, track_number, duration, mbid, image)
	VALUES ($1, $2, $3, $4, $5, $6, $7)
	RETURNING song_id`
	row := store.QueryRow(query, s.Artist, s.Album, s.Name, s.TrackNumber,
		s.Duration, s.Mbid, s.Image)
	return row.Scan(&s.Id)
}

func (store *SqlStore) InsertUser(user *User) error {
	query := `
	INSERT into users (type, op_id, name, email)
	VALUES ($1, $2, $3, $4) RETURNING user_id`
	row := store.QueryRow(query, user.Type, user.OpId, user.Name, user.Email)
	return row.Scan(&user.Id)
}

func (store *SqlStore) GetUser(user *User) error {
	var query string
	var row *sql.Row
	if user.Id == 0 {
		query = `
		SELECT user_id, name, email, lfm_name
		FROM users WHERE type=$1 AND op_id=$2`
		row = store.QueryRow(query, user.Type, user.OpId)
	} else {
		query = `
		SELECT user_id, name, email, lfm_name
		FROM users WHERE user_id=$1`
		row = store.QueryRow(query, user.Id)
	}
	return row.Scan(&user.Id, &user.Name, &user.Email, &user.LfmName)
}

func (store *SqlStore) SaveUser(user *User) error {
	var err error
	var query string
	if user.LfmPassword != "" {
		query = `
		UPDATE users SET name=$1, email=$2, lfm_name=$3, lfm_password=$4
		WHERE  user_id=$5`
		_, err = store.Exec(query, user.Name, user.Email, user.LfmName,
			user.LfmPassword, user.Id)
	} else {
		query = `
		UPDATE users SET name=$1, email=$2, lfm_name=$3 WHERE  user_id=$5`
		_, err = store.Exec(query, user.Name, user.Email, user.LfmName, user.Id)

	}
	return err
}

func (store *SqlStore) InsertUserSession(s *UserSession) error {
	query := `INSERT into user_sessions values ($1, $2)`
	_, err := store.Exec(query, &s.Id, &s.UserId)
	return err
}

func (store *SqlStore) SaveImport(i *Import) error {
	query := `UPDATE scrobble_import SET last_fetch=$1, done=$5, count=$6
	WHERE "from"=$2 and "to"=$3 and lfm_name=$4`
	_, err := store.Exec(query, i.LastFetch, i.From, i.To, i.LfmName, i.Done, i.Count)
	return err
}

func (store *SqlStore) InsertImport(i *Import) error {
	query := `
	INSERT into scrobble_import (lfm_name, "from", "to", last_fetch, done, count)
	VALUES ($1, $2, $3, $4, $5, $6)`
	_, err := store.Exec(query, i.LfmName, i.From, i.To, i.LastFetch, i.Done, i.Count)
	return err
}

func (store *SqlStore) NewImport(name string) *Import {
	i := &Import{
		LfmName: name,
		To:      time.Now(),
	}
	query := `SELECT max("to") FROM scrobble_import WHERE lfm_name=$1`
	row := store.QueryRow(query, i.LfmName)
	row.Scan(&i.From)
	if err := store.InsertImport(i); err != nil {
		log.Println(err)
	}
	return i
}

func (store *SqlStore) ImportStats(name string) (*Import, error) {
	query := `
	SELECT max("to"), sum(count)
	FROM scrobble_import
	WHERE lfm_name=$1
	GROUP BY lfm_name`
	i := new(Import)
	row := store.QueryRow(query, name)
	err := row.Scan(&i.To, &i.Count)
	return i, err
}

func (store *SqlStore) InsertLoveImport(i *LoveImport) error {
	query := `
	INSERT INTO love_import (lfm_name, count) VALUES ($1, $2)`
	_, err := store.Exec(query, i.LfmName, i.Count)
	return err
}

func (store *SqlStore) InsertLovedTracks(lt []LovedTrack, se *Session) error {
	tx, err := store.Begin()
	if err != nil {
		return err
	}
	query := `
	INSERT INTO love
	(artist, name, mbid, time, session, "user")
	VALUES ($1, $2, $3, $4, $5, $6)`
	st, err := tx.Prepare(query)
	if err != nil {
		return err
	}

	for _, t := range lt {
		_, err = st.Exec(t.Artist.Name, t.Name, t.Mbid, t.Date.ToTime(),
			se.Key, se.UserId)
		if err != nil {
			tx.Rollback()
			return err
		}
	}
	return tx.Commit()
}
func (store *SqlStore) LoveImportStats(name string) (*LoveImport, error) {
	query := `
	SELECT max(time), sum(count) FROM love_import
	WHERE lfm_name = $1 GROUP BY lfm_name`
	li := new(LoveImport)
	row := store.QueryRow(query, name)
	err := row.Scan(&li.Time, &li.Count)
	return li, err
}