mew/ui/qt/widgets/vlcframe.py

import time
from collections import deque

import vlc
from PyQt5 import QtWidgets, QtGui, QtCore
from PyQt5.QtCore import pyqtSignal
from PyQt5.QtGui import QIcon

from ui.qt.widgets.vlcframe_ui import Ui_VlcFrame


class VlcFrame(QtWidgets.QFrame):
    DEFAULT_VOLUME = 50
    trackStarted = pyqtSignal(object)
    trackEnded = pyqtSignal(object)
    playlistStarted = pyqtSignal(object)
    playlistEnded = pyqtSignal(object)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._media = None
        self._is_paused = True
        self.is_muted = False
        self.volume = self.DEFAULT_VOLUME

        self.playlist = None
        self.tracks = deque()
        self.current_index = None

        # Create a basic vlc instance
        self._instance = vlc.Instance()

        # Create an empty vlc media player
        self._mediaplayer = self._instance.media_player_new()

        self.createWidgets()

    def createWidgets(self):
        self.ui = Ui_VlcFrame()
        self.ui.setupUi(self)

        self.ui.progressionSlider.sliderMoved.connect(self.set_position)
        self.ui.progressionSlider.sliderPressed.connect(self.set_position)
        self.ui.progressionSlider.positionClicked.connect(self.set_position)

        self.ui.btnPlayPause.clicked.connect(self.play_pause)

        self.ui.volumeSlider.setValue(self.volume)
        self._mediaplayer.audio_set_volume(self.volume)
        self.ui.volumeSlider.valueChanged.connect(self.set_volume)
        self.ui.volumeSlider.positionClicked.connect(self.set_volume)

        self.ui.btnMute.clicked.connect(self.toggle_muted)

        self.ui.btnPrevious.clicked.connect(self.go_to_previous_track)
        self.ui.btnNext.clicked.connect(self.go_to_next_track)

        self.timer = QtCore.QTimer(self)
        self.timer.setInterval(100)
        self.timer.timeout.connect(self.update_ui)

        self.setEnabled(False)

    def load_playlist(self, playlist, tracks, start_at=0):
        self.tracks = deque(tracks)
        self.current_index = start_at
        self.playlist = playlist

    def load_track(self, track):
        self.tracks = deque([track])
        self.current_index = 0
        self.playlist = None

    @property
    def currentTrack(self):
        if self.current_index is None:
            return None
        return self.tracks[self.current_index]

    def play(self):

        track = self.currentTrack

        self._media = self._instance.media_new(track.path)

        # Put the media in the media player
        self._mediaplayer.set_media(self._media)

        # Parse the metadata of the file
        self._media.parse()

        self.play_pause()

        self.setEnabled(True)

        if self.playlist:
            self.playlistStarted.emit(self.playlist)
        self.trackStarted.emit(self.currentTrack)

        self.refresh_ui()

    def refresh_ui(self):
        self.ui.btnPrevious.setEnabled(
            len(self.tracks) > 0 and self.current_index > 0
        )
        self.ui.btnNext.setEnabled(
            len(self.tracks) > 0 and self.current_index < (len(self.tracks) - 1)
        )
        # Set the title of the track
        self.ui.lblTrack.setText(f"{self.currentTrack.artist or '(artiste inconnu)'} - {self.currentTrack.title}")
        self.ui.lblDuration.setText(self.currentTrack.literal_duration())

    def play_pause(self):
        """Toggle play/pause status
        """
        if self._mediaplayer.is_playing():
            self._mediaplayer.pause()
            self.ui.btnPlayPause.setIcon(QIcon(":/img/rsc/play.png"))
            self._is_paused = True
            self.timer.stop()
        else:
            if self._mediaplayer.play() == -1:
                return

            self._mediaplayer.play()
            self.ui.btnPlayPause.setIcon(QIcon(":/img/rsc/pause.png"))
            self.timer.start()
            self._is_paused = False

    def stop(self):
        """Stop player
        """
        self._mediaplayer.stop()
        self.ui.btnPlayPause.setIcon(QIcon(":/img/rsc/play.png"))
        self.ui.progressionSlider.setSliderPosition(0)

        if self.playlist:
            self.playlistEnded.emit(self.playlist)
        self.trackEnded.emit(self.currentTrack)

        if len(self.tracks) > 0 and self.current_index < (len(self.tracks) - 1):
            self.current_index += 1
            self.play()
        else:
            self.current_index = None

    def go_to_previous_track(self):
        if not len(self.tracks) > 0 or self.current_index == 0:
            return
        self.current_index -= 1
        self.play()

    def go_to_next_track(self):
        if not len(self.tracks) > 0 or self.current_index == (len(self.tracks) - 1):
            return
        self.current_index += 1
        self.play()

    def update_ui(self):
        """Updates the user interface"""

        # Set the slider's position to its corresponding media position
        # Note that the setValue function only takes values of type int,
        # so we must first convert the corresponding media position.
        media_pos = int(self._mediaplayer.get_position() * 1000)

        self.ui.progressionSlider.setValue(media_pos)

        if self.currentTrack:
            time_pos = media_pos * self.currentTrack.duration // 1000
            self.ui.lblPosition.setText(time.strftime("%M:%S", time.gmtime(time_pos)))

        # No need to call this function if nothing is played
        if not self._mediaplayer.is_playing():
            self.timer.stop()

            # After the video finished, the play button stills shows "Pause",
            # which is not the desired behavior of a media player.
            # This fixes that "bug".
            if not self._is_paused:
                self.stop()

    def set_volume(self, volume):
        """Set the volume
        """
        # if muted: unmute
        if self.is_muted:
            self.toggle_muted()

        self._mediaplayer.audio_set_volume(volume)
        self.volume = volume
        self.ui.volumeSlider.setValue(volume)

    def set_position(self, position=None):
        """Set the movie position according to the position slider.
        """
        # The vlc MediaPlayer needs a float value between 0 and 1, Qt uses
        # integer variables, so you need a factor; the higher the factor, the
        # more precise are the results (1000 should suffice).

        # if paused: resume
        if self._is_paused:
            self.play_pause()

        # Set the media position to where the slider was dragged
        self.timer.stop()
        pos = self.ui.progressionSlider.value()
        self._mediaplayer.set_position(pos / 1000.0)
        self.timer.start()

    def toggle_muted(self):
        if not self.is_muted:
            self._mediaplayer.audio_set_volume(0)
            self.ui.btnMute.setIcon(QIcon(":/img/rsc/mute.png"))
            self.is_muted = True
        else:
            self._mediaplayer.audio_set_volume(self.volume)
            self.ui.btnMute.setIcon(QIcon(":/img/rsc/volume.png"))
            self.is_muted = False

    def current(self):
        return self.currentTrack