Add iTunes-style playback bar and move Output Directory to Settings

- Add QMediaPlayer + QAudioOutput for playback within the app
- Playback bar at top of Library tab with:
  - Transport controls: Prev, Play/Pause, Next
  - Seekable progress slider with current/total time labels
  - Volume slider
  - Now playing label showing Artist - Title
- Double-click table row to start playback
- Playback auto-advances to next track on end
- Move Output Directory setting from Library tab to Settings tab
- Output Directory now shown in a dedicated 'Library' group in Settings
- Add _setup_player(), _play_track_from_index(), _format_time_ms()
- Add all playback handlers for position, duration, status changes

src/main.py

@@ -15,9 +15,10 @@ from PyQt6.QtWidgets import (
     QPushButton, QLabel, QLineEdit, QProgressBar, QFileDialog,
     QComboBox, QCheckBox, QTabWidget, QListWidget, QListWidgetItem,
     QMessageBox, QSpinBox, QGroupBox, QHeaderView,
-    QTableWidget, QTableWidgetItem
+    QTableWidget, QTableWidgetItem, QSlider
 )
-from PyQt6.QtCore import Qt, QThread, pyqtSignal
+from PyQt6.QtCore import Qt, QThread, pyqtSignal, QUrl
+from PyQt6.QtMultimedia import QMediaPlayer, QAudioOutput
 
 from youtube_downloader import YouTubeDownloader, TrackInfo
 from audio_converter import AudioConverter
@@ -221,7 +222,13 @@ class MainWindow(QMainWindow):
         self.ipod_devices: List[Dict] = []
         self.current_mount_point: Optional[str] = None
 
+        self.player: Optional[QMediaPlayer] = None
+        self.audio_output: Optional[QAudioOutput] = None
+        self.current_playback_index: int = -1
+        self._is_playing = False
+
         self._setup_ui()
+        self._setup_player()
         self._scan_library()
         self._on_refresh_devices_clicked()
 
@@ -310,19 +317,80 @@ class MainWindow(QMainWindow):
     def _setup_library_tab(self, tab):
         layout = QVBoxLayout(tab)
 
-        output_layout = QHBoxLayout()
-        output_label = QLabel("Output Directory:")
-        self.output_dir_input = QLineEdit()
-        self.output_dir_input.setText(os.path.join(os.path.expanduser("~"), "Music", "iPod"))
-        browse_btn = QPushButton("Browse...")
-        browse_btn.clicked.connect(self._on_browse_output_clicked)
-        refresh_btn = QPushButton("Refresh")
+        # === Playback controls bar ===
+        playback_group = QGroupBox()
+        playback_layout = QVBoxLayout(playback_group)
+        playback_layout.setContentsMargins(8, 6, 8, 6)
+
+        # Top row: transport buttons + progress + time + volume
+        controls_row = QHBoxLayout()
+        controls_row.setSpacing(8)
+
+        self.prev_btn = QPushButton("\u23EE")
+        self.prev_btn.setFixedWidth(36)
+        self.prev_btn.clicked.connect(self._on_prev_clicked)
+
+        self.play_btn = QPushButton("\u25B6")
+        self.play_btn.setFixedWidth(44)
+        self.play_btn.clicked.connect(self._on_play_pause_clicked)
+
+        self.next_btn = QPushButton("\u23ED")
+        self.next_btn.setFixedWidth(36)
+        self.next_btn.clicked.connect(self._on_next_clicked)
+
+        controls_row.addWidget(self.prev_btn)
+        controls_row.addWidget(self.play_btn)
+        controls_row.addWidget(self.next_btn)
+
+        self.time_label_start = QLabel("0:00")
+        self.time_label_start.setFixedWidth(40)
+        self.time_label_start.setAlignment(Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignVCenter)
+
+        self.position_slider = QSlider(Qt.Orientation.Horizontal)
+        self.position_slider.setMinimum(0)
+        self.position_slider.setMaximum(1000)
+        self.position_slider.setValue(0)
+        self.position_slider.sliderPressed.connect(self._on_slider_pressed)
+        self.position_slider.sliderReleased.connect(self._on_slider_released)
+
+        self.time_label_end = QLabel("0:00")
+        self.time_label_end.setFixedWidth(40)
+        self.time_label_end.setAlignment(Qt.AlignmentFlag.AlignLeft | Qt.AlignmentFlag.AlignVCenter)
+
+        controls_row.addWidget(self.time_label_start)
+        controls_row.addWidget(self.position_slider, stretch=1)
+        controls_row.addWidget(self.time_label_end)
+
+        vol_icon = QLabel("\U0001F50A")
+        self.volume_slider = QSlider(Qt.Orientation.Horizontal)
+        self.volume_slider.setFixedWidth(80)
+        self.volume_slider.setRange(0, 100)
+        self.volume_slider.setValue(80)
+        self.volume_slider.valueChanged.connect(self._on_volume_changed)
+
+        controls_row.addWidget(vol_icon)
+        controls_row.addWidget(self.volume_slider)
+        playback_layout.addLayout(controls_row)
+
+        # Bottom row: now playing info
+        self.now_playing_label = QLabel("Select a track to play")
+        self.now_playing_label.setAlignment(Qt.AlignmentFlag.AlignCenter)
+        self.now_playing_label.setStyleSheet("color: palette(mid); font-size: 12px;")
+        now_playing_layout = QHBoxLayout()
+        now_playing_layout.addStretch()
+        now_playing_layout.addWidget(self.now_playing_label)
+        now_playing_layout.addStretch()
+        playback_layout.addLayout(now_playing_layout)
+
+        layout.addWidget(playback_group)
+
+        # Refresh button
+        refresh_row = QHBoxLayout()
+        refresh_btn = QPushButton("\u21BB Refresh Library")
         refresh_btn.clicked.connect(self._on_refresh_library_clicked)
-        output_layout.addWidget(output_label)
-        output_layout.addWidget(self.output_dir_input)
-        output_layout.addWidget(browse_btn)
-        output_layout.addWidget(refresh_btn)
-        layout.addLayout(output_layout)
+        refresh_row.addStretch()
+        refresh_row.addWidget(refresh_btn)
+        layout.addLayout(refresh_row)
 
         self.ready_label = QLabel("Ready to Transfer:")
         layout.addWidget(self.ready_label)
@@ -337,6 +405,7 @@ class MainWindow(QMainWindow):
         self.library_ready_table.setEditTriggers(QTableWidget.EditTrigger.NoEditTriggers)
         self.library_ready_table.setAlternatingRowColors(True)
         self.library_ready_table.setSortingEnabled(True)
+        self.library_ready_table.cellDoubleClicked.connect(self._on_table_double_clicked)
 
         header = self.library_ready_table.horizontalHeader()
         header.setSectionResizeMode(1, QHeaderView.ResizeMode.Stretch)
@@ -369,7 +438,7 @@ class MainWindow(QMainWindow):
         self.library_convert_btn.clicked.connect(self._on_library_convert_clicked)
         layout.addWidget(self.library_convert_btn)
 
-        self.library_transfer_btn = QPushButton("Transfer Selected to iPod ▸")
+        self.library_transfer_btn = QPushButton("Transfer Selected to iPod \u25B8")
         self.library_transfer_btn.clicked.connect(self._on_library_transfer_clicked)
         layout.addWidget(self.library_transfer_btn)
 
@@ -433,6 +502,21 @@ class MainWindow(QMainWindow):
     def _setup_settings_tab(self, tab):
         layout = QVBoxLayout(tab)
 
+        library_group = QGroupBox("Library")
+        library_layout = QVBoxLayout(library_group)
+
+        output_layout = QHBoxLayout()
+        output_label = QLabel("Output Directory:")
+        self.output_dir_input = QLineEdit()
+        self.output_dir_input.setText(os.path.join(os.path.expanduser("~"), "Music", "iPod"))
+        browse_btn = QPushButton("Browse...")
+        browse_btn.clicked.connect(self._on_browse_output_clicked)
+        output_layout.addWidget(output_label)
+        output_layout.addWidget(self.output_dir_input)
+        output_layout.addWidget(browse_btn)
+        library_layout.addLayout(output_layout)
+        layout.addWidget(library_group)
+
         video_group = QGroupBox("Video Support")
         video_layout = QVBoxLayout(video_group)
 
@@ -488,6 +572,118 @@ class MainWindow(QMainWindow):
         about_label.setAlignment(Qt.AlignmentFlag.AlignCenter)
         layout.addWidget(about_label)
 
+    def _setup_player(self):
+        """Initialize QMediaPlayer and QAudioOutput for playback."""
+        self.player = QMediaPlayer()
+        self.audio_output = QAudioOutput()
+        self.audio_output.setVolume(0.8)
+        self.player.setAudioOutput(self.audio_output)
+
+        self.player.positionChanged.connect(self._on_media_position_changed)
+        self.player.durationChanged.connect(self._on_media_duration_changed)
+        self.player.mediaStatusChanged.connect(self._on_media_status_changed)
+
+    def _play_track_from_index(self, index: int):
+        """Start playing a track from the library table by row index."""
+        if index < 0 or index >= self.library_ready_table.rowCount():
+            return
+        data_item = self.library_ready_table.item(index, 0)
+        if data_item is None:
+            return
+        track_data = data_item.data(Qt.ItemDataRole.UserRole)
+        if not track_data or not os.path.exists(track_data.get("path", "")):
+            return
+
+        self.current_playback_index = index
+        self.player.setSource(QUrl.fromLocalFile(track_data["path"]))
+        self.player.play()
+        self._is_playing = True
+        self.play_btn.setText("\u23F8")
+
+        self.now_playing_label.setText(f"{track_data['artist']}  \u2014  {track_data['title']}")
+        self.now_playing_label.setStyleSheet(
+            "color: palette(text); font-weight: bold;"
+        )
+
+        # Highlight the current row
+        self.library_ready_table.clearSelection()
+        self.library_ready_table.selectRow(index)
+
+    def _on_play_pause_clicked(self):
+        if self.player is None:
+            return
+        if self.player.playbackState() == QMediaPlayer.PlaybackState.PlayingState:
+            self.player.pause()
+            self._is_playing = False
+            self.play_btn.setText("\u25B6")
+        else:
+            if self.player.playbackState() == QMediaPlayer.PlaybackState.StoppedState:
+                # Nothing playing yet — play first selected row or row 0
+                selected_rows = {item.row() for item in self.library_ready_table.selectedItems()}
+                start = min(selected_rows) if selected_rows else 0
+                self._play_track_from_index(start)
+            else:
+                self.player.play()
+                self._is_playing = True
+                self.play_btn.setText("\u23F8")
+
+    def _on_prev_clicked(self):
+        if self.player is None:
+            return
+        if self.player.position() > 3000:
+            self.player.setPosition(0)
+            return
+        idx = max(0, self.current_playback_index - 1)
+        self._play_track_from_index(idx)
+
+    def _on_next_clicked(self):
+        if self.player is None:
+            return
+        idx = min(self.library_ready_table.rowCount() - 1, self.current_playback_index + 1)
+        self._play_track_from_index(idx)
+
+    def _on_slider_pressed(self):
+        if self.player:
+            self.player.setPosition(
+                int(self.position_slider.value() / 1000.0 * self.player.duration())
+            )
+
+    def _on_slider_released(self):
+        pass
+
+    def _on_volume_changed(self, value):
+        if self.audio_output:
+            self.audio_output.setVolume(value / 100.0)
+
+    def _on_media_position_changed(self, position: int):
+        if self.position_slider is None or self.player is None:
+            return
+        duration = self.player.duration()
+        if duration > 0 and not self.position_slider.isSliderDown():
+            self.position_slider.setValue(int(position / duration * 1000))
+        self.time_label_start.setText(self._format_time_ms(position))
+
+    def _on_media_duration_changed(self, duration: int):
+        self.time_label_end.setText(self._format_time_ms(duration))
+        if self.position_slider and not self.position_slider.isSliderDown():
+            self.position_slider.setValue(0)
+
+    def _on_media_status_changed(self, status):
+        if status == QMediaPlayer.MediaStatus.EndOfMedia:
+            self._on_next_clicked()
+        elif status == QMediaPlayer.MediaStatus.NoMedia:
+            self.play_btn.setText("\u25B6")
+            self._is_playing = False
+
+    def _on_table_double_clicked(self, row: int):
+        self._play_track_from_index(row)
+
+    @staticmethod
+    def _format_time_ms(ms: int) -> str:
+        total_seconds = ms // 1000
+        m, s = divmod(total_seconds, 60)
+        return f"{m}:{s:02d}"
+
     def _format_duration(self, seconds: int) -> str:
         if seconds <= 0:
             return "??:??"