v1.2.1

CHANGELOG.md

@@ -1,3 +1,12 @@
+# 1.2.1
+- Upgraded Abogen's interface from PyQt5 to PyQt6 for better compatibility and long-term support.
+- Added tooltip indicators in queue manager to display book handler options (`Save chapters separately` and `Merge chapters at the end`) for queued items.
+- Added `Open processed file` and `Open input file` options for items in the queue manager, instead of just `Open file` option.
+- Added loading gif animation to book handler window.
+- Fixed light theme slider colors in voice mixer for better visibility (for non-Windows users).
+- Fixed subtitle word-count splitting logic for more accurate segmentation.
+- Improvements in code and documentation.
+
 # 1.2.0
 - Added `Line` option to subtitle generation modes, allowing subtitles to be generated based on line breaks in the text, by @mleg in #94.
 - Added a loading indicator to the book handler window for better user experience during book preprocessing.

abogen/Dockerfile

@@ -12,7 +12,7 @@ RUN apt-get update \
         python3 \
         python3-venv \
         python3-pip \
-        python3-pyqt5 \
+        python3-pyqt6 \
         espeak-ng \
  && apt-get clean \
  && rm -rf /var/lib/apt/lists/*

abogen/VERSION

@@ -1 +1 @@
-1.2.0
+1.2.1

abogen/constants.py

@@ -148,6 +148,7 @@ COLORS = {
     "BLUE_BORDER_HOVER": "#6ab0de",
     "YELLOW_BACKGROUND": "rgba(255, 221, 51, 0.40)",
     "GREY_BACKGROUND": "rgba(128, 128, 128, 0.15)",
+    "GREY_BORDER": "#808080",
     "RED_BACKGROUND": "rgba(232, 78, 60, 0.15)",
     "RED_BG": "rgba(232, 78, 60, 0.10)",
     "RED_BG_HOVER": "rgba(232, 78, 60, 0.15)",

abogen/conversion.py

@@ -3,10 +3,15 @@ import re
 import time
 import hashlib  # For generating unique cache filenames
 from platformdirs import user_desktop_dir
-from PyQt5.QtCore import QThread, pyqtSignal, Qt, QTimer
-from PyQt5.QtWidgets import QCheckBox, QVBoxLayout, QDialog, QLabel, QDialogButtonBox
+from PyQt6.QtCore import QThread, pyqtSignal, Qt, QTimer
+from PyQt6.QtWidgets import QCheckBox, QVBoxLayout, QDialog, QLabel, QDialogButtonBox
 import soundfile as sf
-from abogen.utils import clean_text, create_process, get_user_cache_path, detect_encoding
+from abogen.utils import (
+    clean_text,
+    create_process,
+    get_user_cache_path,
+    detect_encoding,
+)
 from abogen.constants import (
     LANGUAGE_DESCRIPTIONS,
     SAMPLE_VOICE_TEXTS,
@@ -47,43 +52,45 @@ def sanitize_name_for_os(name, is_folder=True):
     if system == "Windows":
         # Windows illegal characters: < > : " / \ | ? *
         # Also can't end with space or dot
-        sanitized = re.sub(r'[<>:"/\\|?*]', '_', name)
+        sanitized = re.sub(r'[<>:"/\\|?*]', "_", name)
         # Remove control characters (0-31)
-        sanitized = re.sub(r'[\x00-\x1f]', '_', sanitized)
+        sanitized = re.sub(r"[\x00-\x1f]", "_", sanitized)
         # Remove trailing spaces and dots
-        sanitized = sanitized.rstrip('. ')
+        sanitized = sanitized.rstrip(". ")
         # Windows reserved names (CON, PRN, AUX, NUL, COM1-9, LPT1-9)
-        reserved = ['CON', 'PRN', 'AUX', 'NUL'] + \
-                   [f'COM{i}' for i in range(1, 10)] + \
-                   [f'LPT{i}' for i in range(1, 10)]
-        if sanitized.upper() in reserved or sanitized.upper().split('.')[0] in reserved:
+        reserved = (
+            ["CON", "PRN", "AUX", "NUL"]
+            + [f"COM{i}" for i in range(1, 10)]
+            + [f"LPT{i}" for i in range(1, 10)]
+        )
+        if sanitized.upper() in reserved or sanitized.upper().split(".")[0] in reserved:
             sanitized = f"_{sanitized}"
     elif system == "Darwin":  # macOS
         # macOS illegal characters: : (colon is converted to / by the system)
         # Also can't start with dot (hidden file) for folders typically
-        sanitized = re.sub(r'[:]', '_', name)
+        sanitized = re.sub(r"[:]", "_", name)
         # Remove control characters
-        sanitized = re.sub(r'[\x00-\x1f]', '_', sanitized)
+        sanitized = re.sub(r"[\x00-\x1f]", "_", sanitized)
         # Avoid leading dot for folders (creates hidden folders)
-        if is_folder and sanitized.startswith('.'):
-            sanitized = '_' + sanitized[1:]
+        if is_folder and sanitized.startswith("."):
+            sanitized = "_" + sanitized[1:]
     else:  # Linux and others
         # Linux illegal characters: / and null character
         # Though / is illegal, most other chars are technically allowed
-        sanitized = re.sub(r'[/\x00]', '_', name)
+        sanitized = re.sub(r"[/\x00]", "_", name)
         # Remove other control characters for safety
-        sanitized = re.sub(r'[\x01-\x1f]', '_', sanitized)
+        sanitized = re.sub(r"[\x01-\x1f]", "_", sanitized)
         # Avoid leading dot for folders (creates hidden folders)
-        if is_folder and sanitized.startswith('.'):
-            sanitized = '_' + sanitized[1:]
+        if is_folder and sanitized.startswith("."):
+            sanitized = "_" + sanitized[1:]
 
     # Ensure the name is not empty after sanitization
-    if not sanitized or sanitized.strip() == '':
+    if not sanitized or sanitized.strip() == "":
         sanitized = "audiobook"
 
     # Limit length to 255 characters (common limit across filesystems)
     if len(sanitized) > 255:
-        sanitized = sanitized[:255].rstrip('. ')
+        sanitized = sanitized[:255].rstrip(". ")
 
     return sanitized
 
@@ -96,8 +103,8 @@ class ChapterOptionsDialog(QDialog):
         # Prevent closing with the X button and remove the help button
         self.setWindowFlags(
             self.windowFlags()
-            & ~Qt.WindowCloseButtonHint
-            & ~Qt.WindowContextHelpButtonHint
+            & ~Qt.WindowType.WindowCloseButtonHint
+            & ~Qt.WindowType.WindowContextHelpButtonHint
         )
 
         layout = QVBoxLayout(self)
@@ -131,7 +138,7 @@ class ChapterOptionsDialog(QDialog):
         layout.addWidget(self.countdown_label)
 
         # Add OK button
-        button_box = QDialogButtonBox(QDialogButtonBox.Ok)
+        button_box = QDialogButtonBox(QDialogButtonBox.StandardButton.Ok)
         button_box.accepted.connect(self.accept)
         layout.addWidget(button_box)
 
@@ -180,7 +187,7 @@ class ChapterOptionsDialog(QDialog):
 
     # Prevent escape key from closing the dialog
     def keyPressEvent(self, event):
-        if event.key() == Qt.Key_Escape:
+        if event.key() == Qt.Key.Key_Escape:
             event.ignore()
         else:
             super().keyPressEvent(event)
@@ -310,7 +317,11 @@ class ConversionThread(QThread):
 
             # Normalize paths for consistent display (fixes Windows path separator issues)
             input_file = os.path.normpath(input_file) if input_file else input_file
-            processing_file = os.path.normpath(processing_file) if processing_file else processing_file
+            processing_file = (
+                os.path.normpath(processing_file)
+                if processing_file
+                else processing_file
+            )
 
             self.log_updated.emit(f"- Input File: {input_file}")
             if input_file != processing_file:
@@ -318,7 +329,9 @@ class ConversionThread(QThread):
 
             # Use file_name for logs if from_queue, otherwise use display_path if available
             if getattr(self, "from_queue", False):
-                base_path = self.save_base_path or self.file_name  # Use save_base_path if available
+                base_path = (
+                    self.save_base_path or self.file_name
+                )  # Use save_base_path if available
             else:
                 base_path = self.display_path if self.display_path else self.file_name
 
@@ -476,7 +489,9 @@ class ConversionThread(QThread):
 
             # Use file_name for logs if from_queue, otherwise use display_path if available
             if getattr(self, "from_queue", False):
-                base_path = self.save_base_path or self.file_name  # Use save_base_path if available
+                base_path = (
+                    self.save_base_path or self.file_name
+                )  # Use save_base_path if available
             else:
                 base_path = self.display_path if self.display_path else self.file_name
 
@@ -528,7 +543,9 @@ class ConversionThread(QThread):
             # Prepare merged output file for incremental writing ONLY if merge_chapters_at_end is True
             if merge_chapters_at_end:
                 out_dir = parent_dir
-                base_filepath_no_ext = os.path.join(out_dir, f"{sanitized_base_name}{suffix}")
+                base_filepath_no_ext = os.path.join(
+                    out_dir, f"{sanitized_base_name}{suffix}"
+                )
                 merged_out_path = f"{base_filepath_no_ext}.{self.output_format}"
                 subtitle_entries = []
                 current_time = 0.0
@@ -642,8 +659,12 @@ class ConversionThread(QThread):
                         # Add style definitions for karaoke highlighting
                         if self.subtitle_mode == "Sentence + Highlighting":
                             merged_subtitle_file.write("[V4+ Styles]\n")
-                            merged_subtitle_file.write("Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding\n")
-                            merged_subtitle_file.write("Style: Default,Arial,24,&H00FFFFFF,&H00808080,&H00000000,&H00404040,0,0,0,0,100,100,0,0,3,2,0,5,10,10,10,1\n\n")
+                            merged_subtitle_file.write(
+                                "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding\n"
+                            )
+                            merged_subtitle_file.write(
+                                "Style: Default,Arial,24,&H00FFFFFF,&H00808080,&H00000000,&H00404040,0,0,0,0,100,100,0,0,3,2,0,5,10,10,10,1\n\n"
+                            )
                         merged_subtitle_file.write("[Events]\n")
                         merged_subtitle_file.write(
                             "Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text\n"
@@ -806,8 +827,12 @@ class ConversionThread(QThread):
                             # Add style definitions for karaoke highlighting
                             if self.subtitle_mode == "Sentence + Highlighting":
                                 chapter_subtitle_file.write("[V4+ Styles]\n")
-                                chapter_subtitle_file.write("Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding\n")
-                                chapter_subtitle_file.write("Style: Default,Arial,24,&H00FFFFFF,&H00808080,&H00000000,&H00404040,0,0,0,0,100,100,0,0,3,2,0,5,10,10,10,1\n\n")
+                                chapter_subtitle_file.write(
+                                    "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding\n"
+                                )
+                                chapter_subtitle_file.write(
+                                    "Style: Default,Arial,24,&H00FFFFFF,&H00808080,&H00000000,&H00404040,0,0,0,0,100,100,0,0,3,2,0,5,10,10,10,1\n\n"
+                                )
 
                             chapter_subtitle_file.write("[Events]\n")
                             chapter_subtitle_file.write(
@@ -922,7 +947,12 @@ class ConversionThread(QThread):
                                         start_time = self._ass_time(start)
                                         end_time = self._ass_time(end)
                                         # Use karaoke effect for highlighting mode
-                                        effect = "karaoke" if self.subtitle_mode == "Sentence + Highlighting" else ""
+                                        effect = (
+                                            "karaoke"
+                                            if self.subtitle_mode
+                                            == "Sentence + Highlighting"
+                                            else ""
+                                        )
                                         merged_subtitle_file.write(
                                             f"Dialogue: 0,{start_time},{end_time},Default,,{merged_subtitle_margin},{merged_subtitle_margin},0,{effect},{merged_subtitle_alignment_tag}{text}\n"
                                         )
@@ -951,7 +981,12 @@ class ConversionThread(QThread):
                                         start_time = self._ass_time(start)
                                         end_time = self._ass_time(end)
                                         # Use karaoke effect for highlighting mode
-                                        effect = "karaoke" if self.subtitle_mode == "Sentence + Highlighting" else ""
+                                        effect = (
+                                            "karaoke"
+                                            if self.subtitle_mode
+                                            == "Sentence + Highlighting"
+                                            else ""
+                                        )
                                         chapter_subtitle_file.write(
                                             f"Dialogue: 0,{start_time},{end_time},Default,,{chapter_subtitle_margin},{chapter_subtitle_margin},0,{effect},{chapter_subtitle_alignment_tag}{text}\n"
                                         )
@@ -997,7 +1032,9 @@ class ConversionThread(QThread):
 
                 # Add silence between chapters for merged output (except after the last chapter)
                 if merge_chapters_at_end and chapter_idx < total_chapters:
-                    silence_samples = int(self.silence_duration * 24000)  # Silence duration at 24,000 Hz
+                    silence_samples = int(
+                        self.silence_duration * 24000
+                    )  # Silence duration at 24,000 Hz
                     silence_audio = self.np.zeros(silence_samples, dtype="float32")
                     silence_bytes = silence_audio.tobytes()
 
@@ -1297,7 +1334,11 @@ class ConversionThread(QThread):
                         karaoke_text = ""
                         for t in current_sentence:
                             # Calculate duration in centiseconds
-                            duration = t["end"] - t["start"] if t["end"] and t["start"] else 0.5
+                            duration = (
+                                t["end"] - t["start"]
+                                if t["end"] and t["start"]
+                                else 0.5
+                            )
                             duration_cs = int(duration * 100)
                             # Add karaoke effect - relies on style's SecondaryColour for highlighting
                             karaoke_text += f"{{\\kf{duration_cs}}}{t['text']}{t.get('whitespace', '') or ''}"
@@ -1382,23 +1423,48 @@ class ConversionThread(QThread):
                     subtitle_entries[-1] = (start, fallback_end_time, text)
 
         else:
-            # Word count-based grouping
+            # Word count-based grouping - simply count spaces and split after N spaces
             try:
                 word_count = int(self.subtitle_mode.split()[0])
                 word_count = min(word_count, max_subtitle_words)
             except (ValueError, IndexError):
                 word_count = 1
 
-            # Group words into subtitle entries (processed_tokens already has punctuation combined)
-            for i in range(0, len(processed_tokens), word_count):
-                group = processed_tokens[i : i + word_count]
-                if group:
-                    text = "".join(
-                        t["text"] + (t.get("whitespace", "") or "") for t in group
-                    )
-                    subtitle_entries.append(
-                        (group[0]["start"], group[-1]["end"], text.strip())
-                    )
+            current_group = []
+            space_count = 0
+
+            for token in processed_tokens:
+                current_group.append(token)
+
+                # Count spaces after tokens (in the whitespace field)
+                if token.get("whitespace", "") == " ":
+                    space_count += 1
+
+                    # Split after counting N spaces
+                    if space_count >= word_count:
+                        text = "".join(
+                            t["text"] + (t.get("whitespace", "") or "")
+                            for t in current_group
+                        )
+                        subtitle_entries.append(
+                            (
+                                current_group[0]["start"],
+                                current_group[-1]["end"],
+                                text.strip(),
+                            )
+                        )
+                        current_group = []
+                        space_count = 0
+
+            # Add any remaining tokens
+            if current_group:
+                text = "".join(
+                    t["text"] + (t.get("whitespace", "") or "") for t in current_group
+                )
+                subtitle_entries.append(
+                    (current_group[0]["start"], current_group[-1]["end"], text.strip())
+                )
+
             # Fallback for last entry
             if subtitle_entries and fallback_end_time is not None:
                 last_entry = subtitle_entries[-1]
@@ -1406,7 +1472,6 @@ class ConversionThread(QThread):
                 if end is None or end <= start or end <= 0:
                     subtitle_entries[-1] = (start, fallback_end_time, text)
 
-
     def cancel(self):
         self.cancel_requested = True
         self.should_cancel = True

abogen/main.py

@@ -1,4 +1,3 @@
-from json import load
 import os
 import sys
 import platform
@@ -7,33 +6,43 @@ import signal
 
 # Qt platform plugin detection (fixes #59)
 try:
-    from PyQt5.QtCore import QLibraryInfo
-    plugins = QLibraryInfo.location(QLibraryInfo.PluginsPath)
+    from PyQt6.QtCore import QLibraryInfo
+
+    # Get the path to the plugins directory
+    plugins = QLibraryInfo.path(QLibraryInfo.LibraryPath.PluginsPath)
+
     # Normalize path to use the OS-native separators and absolute path
     platform_dir = os.path.normpath(os.path.join(plugins, "platforms"))
+
     # Ensure we work with an absolute path for clarity
     platform_dir = os.path.abspath(platform_dir)
+
     if os.path.isdir(platform_dir):
         os.environ["QT_QPA_PLATFORM_PLUGIN_PATH"] = platform_dir
         print("QT_QPA_PLATFORM_PLUGIN_PATH set to:", platform_dir)
     else:
-        print("PyQt5 platform plugins not found at", platform_dir)
+        print("PyQt6 platform plugins not found at", platform_dir)
 except ImportError:
-    print("PyQt5 not installed.")
+    print("PyQt6 not installed.")
 
 # Set application ID for Windows taskbar icon
 if platform.system() == "Windows":
     try:
         from abogen.constants import PROGRAM_NAME, VERSION
         import ctypes
+
         app_id = f"{PROGRAM_NAME}.{VERSION}"
         ctypes.windll.shell32.SetCurrentProcessExplicitAppUserModelID(app_id)
     except Exception as e:
         print("Warning: failed to set AppUserModelID:", e)
 
-from PyQt5.QtWidgets import QApplication
-from PyQt5.QtGui import QIcon
-from PyQt5.QtCore import qInstallMessageHandler, QtMsgType
+from PyQt6.QtWidgets import QApplication
+from PyQt6.QtGui import QIcon
+from PyQt6.QtCore import (
+    QLibraryInfo,
+    qInstallMessageHandler,
+    QtMsgType,
+)
 
 # Add the directory to Python path
 sys.path.insert(0, os.path.join(os.path.dirname(__file__)))
@@ -82,10 +91,12 @@ if platform.system() == "Darwin" and platform.processor() == "arm":
 
 # Custom message handler to filter out specific Qt warnings
 def qt_message_handler(mode, context, message):
+    # In PyQt6, the mode is an enum, so we compare with the enum members
     if "Wayland does not support QWindow::requestActivate()" in message:
         return  # Suppress this specific message
     if "setGrabPopup called with a parent, QtWaylandClient" in message:
         return
+
     if mode == QtMsgType.QtWarningMsg:
         print(f"Qt Warning: {message}")
     elif mode == QtMsgType.QtCriticalMsg:
@@ -129,7 +140,7 @@ def main():
 
     ex = abogen()
     ex.show()
-    sys.exit(app.exec_())
+    sys.exit(app.exec())
 
 
 if __name__ == "__main__":

abogen/queue_manager_gui.py

@@ -2,7 +2,7 @@
 # button to remove an item from the queue
 # button to clear the queue
 
-from PyQt5.QtWidgets import (
+from PyQt6.QtWidgets import (
     QDialog,
     QVBoxLayout,
     QHBoxLayout,
@@ -14,18 +14,20 @@ from PyQt5.QtWidgets import (
     QLabel,
     QWidget,
     QSizePolicy,
+    QAbstractItemView,
 )
-from PyQt5.QtCore import QFileInfo, Qt
+from PyQt6.QtCore import QFileInfo, Qt
 from abogen.constants import COLORS
 from copy import deepcopy
-from PyQt5.QtGui import QFontMetrics
+from PyQt6.QtGui import QFontMetrics
 
 
 class ElidedLabel(QLabel):
-    def __init__(self, text, parent=None):
-        super().__init__(text, parent)
+    def __init__(self, text):
+        super().__init__(text)
         self._full_text = text
-        self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Preferred)
+        self.setSizePolicy(QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Preferred)
+        self.setTextFormat(Qt.TextFormat.PlainText)
 
     def setText(self, text):
         self._full_text = text
@@ -34,7 +36,9 @@ class ElidedLabel(QLabel):
 
     def resizeEvent(self, event):
         metrics = QFontMetrics(self.font())
-        elided = metrics.elidedText(self._full_text, Qt.ElideRight, self.width())
+        elided = metrics.elidedText(
+            self._full_text, Qt.TextElideMode.ElideRight, self.width()
+        )
         super().setText(elided)
         super().resizeEvent(event)
 
@@ -53,8 +57,12 @@ class QueueListItemWidget(QWidget):
         name_label = ElidedLabel(os.path.basename(file_name))
         char_label = QLabel(f"Chars: {char_count}")
         char_label.setStyleSheet(f"color: {COLORS['LIGHT_DISABLED']};")
-        char_label.setAlignment(Qt.AlignRight | Qt.AlignVCenter)
-        char_label.setSizePolicy(QSizePolicy.Minimum, QSizePolicy.Preferred)
+        char_label.setAlignment(
+            Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignVCenter
+        )
+        char_label.setSizePolicy(
+            QSizePolicy.Policy.Minimum, QSizePolicy.Policy.Preferred
+        )
         layout.addWidget(name_label, 1)
         layout.addWidget(char_label, 0)
         self.setLayout(layout)
@@ -67,12 +75,14 @@ class DroppableQueueListWidget(QListWidget):
         self.setAcceptDrops(True)
         # Overlay for drag hover
         self.drag_overlay = QLabel("", self)
-        self.drag_overlay.setAlignment(Qt.AlignCenter)
+        self.drag_overlay.setAlignment(Qt.AlignmentFlag.AlignCenter)
         self.drag_overlay.setStyleSheet(
             f"border:2px dashed {COLORS['BLUE_BORDER_HOVER']}; border-radius:5px; padding:20px; background:{COLORS['BLUE_BG_HOVER']};"
         )
         self.drag_overlay.setVisible(False)
-        self.drag_overlay.setAttribute(Qt.WA_TransparentForMouseEvents, True)
+        self.drag_overlay.setAttribute(
+            Qt.WidgetAttribute.WA_TransparentForMouseEvents, True
+        )
 
     def dragEnterEvent(self, event):
         if event.mimeData().hasUrls():
@@ -132,9 +142,11 @@ class QueueManager(QDialog):
         layout.setSpacing(12)  # set spacing between widgets in main layout
         # list of queued items
         self.listwidget = DroppableQueueListWidget(self)
-        self.listwidget.setSelectionMode(QListWidget.ExtendedSelection)
+        self.listwidget.setSelectionMode(
+            QAbstractItemView.SelectionMode.ExtendedSelection
+        )
         self.listwidget.setAlternatingRowColors(True)
-        self.listwidget.setContextMenuPolicy(Qt.CustomContextMenu)
+        self.listwidget.setContextMenuPolicy(Qt.ContextMenuPolicy.CustomContextMenu)
         self.listwidget.customContextMenuRequested.connect(self.show_context_menu)
         # Add informative instructions at the top
         instructions = QLabel(
@@ -145,7 +157,7 @@ class QueueManager(QDialog):
             "Changing the main window configuration afterward <b>does not</b> affect files already in the queue. "
             "You can view each file's configuration by hovering over them."
         )
-        instructions.setAlignment(Qt.AlignLeft)
+        instructions.setAlignment(Qt.AlignmentFlag.AlignLeft)
         instructions.setWordWrap(True)
         instructions.setStyleSheet("margin-bottom: 8px;")
         layout.addWidget(instructions)
@@ -154,12 +166,14 @@ class QueueManager(QDialog):
             "Drag and drop your text files here or use the 'Add files' button.",
             self.listwidget,
         )
-        self.empty_overlay.setAlignment(Qt.AlignCenter)
+        self.empty_overlay.setAlignment(Qt.AlignmentFlag.AlignCenter)
         self.empty_overlay.setStyleSheet(
             f"color: {COLORS['LIGHT_DISABLED']}; background: transparent; padding: 20px;"
         )
         self.empty_overlay.setWordWrap(True)
-        self.empty_overlay.setAttribute(Qt.WA_TransparentForMouseEvents, True)
+        self.empty_overlay.setAttribute(
+            Qt.WidgetAttribute.WA_TransparentForMouseEvents, True
+        )
         self.empty_overlay.hide()
         # add queue items to the list
         self.process_queue()
@@ -192,7 +206,10 @@ class QueueManager(QDialog):
         self.listwidget.currentItemChanged.connect(self.update_button_states)
         self.listwidget.itemSelectionChanged.connect(self.update_button_states)
 
-        buttons = QDialogButtonBox(QDialogButtonBox.Ok | QDialogButtonBox.Cancel, self)
+        buttons = QDialogButtonBox(
+            QDialogButtonBox.StandardButton.Ok | QDialogButtonBox.StandardButton.Cancel,
+            self,
+        )
         buttons.accepted.connect(self.accept)
         buttons.rejected.connect(self.reject)
 
@@ -211,7 +228,6 @@ class QueueManager(QDialog):
 
         self.listwidget.clear()
         if not self.queue:
-            self.empty_overlay.resize(self.listwidget.size())
             self.empty_overlay.show()
             self.update_button_states()
             return
@@ -224,8 +240,16 @@ class QueueManager(QDialog):
             processing_file_path = item.file_name
 
             # Normalize paths for consistent display (fixes Windows path separator issues)
-            display_file_path = os.path.normpath(display_file_path) if display_file_path else display_file_path
-            processing_file_path = os.path.normpath(processing_file_path) if processing_file_path else processing_file_path
+            display_file_path = (
+                os.path.normpath(display_file_path)
+                if display_file_path
+                else display_file_path
+            )
+            processing_file_path = (
+                os.path.normpath(processing_file_path)
+                if processing_file_path
+                else processing_file_path
+            )
 
             # Only show the file name, not the full path
             display_name = display_file_path
@@ -240,13 +264,19 @@ class QueueManager(QDialog):
             # For plain .txt inputs we don't need to show a separate processing file
             show_processing = True
             try:
-                if isinstance(display_file_path, str) and display_file_path.lower().endswith('.txt'):
+                if isinstance(
+                    display_file_path, str
+                ) and display_file_path.lower().endswith(".txt"):
                     show_processing = False
             except Exception:
                 show_processing = True
 
             tooltip = f"<b>Input File:</b> {display_file_path}<br>"
-            if show_processing and processing_file_path and processing_file_path != display_file_path:
+            if (
+                show_processing
+                and processing_file_path
+                and processing_file_path != display_file_path
+            ):
                 tooltip += f"<b>Processing File:</b> {processing_file_path}<br>"
             tooltip += (
                 f"<b>Language:</b> {getattr(item, 'lang_code', '')}<br>"
@@ -262,13 +292,24 @@ class QueueManager(QDialog):
                 f"<b>Characters:</b> {getattr(item, 'total_char_count', '')}<br>"
                 f"<b>Replace Single Newlines:</b> {getattr(item, 'replace_single_newlines', False)}"
             )
+            # Add book handler options if present
+            save_chapters_separately = getattr(item, "save_chapters_separately", None)
+            merge_chapters_at_end = getattr(item, "merge_chapters_at_end", None)
+            if save_chapters_separately is not None:
+                tooltip += f"<br><b>Save chapters separately:</b> {'Yes' if save_chapters_separately else 'No'}"
+                # Only show merge option if saving chapters separately
+                if save_chapters_separately and merge_chapters_at_end is not None:
+                    tooltip += f"<br><b>Merge chapters at the end:</b> {'Yes' if merge_chapters_at_end else 'No'}"
             list_item.setToolTip(tooltip)
             list_item.setIcon(icon)
             # Store both paths for context menu
-            list_item.setData(Qt.UserRole, {
-                'display_path': display_file_path,
-                'processing_path': processing_file_path
-            })
+            list_item.setData(
+                Qt.ItemDataRole.UserRole,
+                {
+                    "display_path": display_file_path,
+                    "processing_path": processing_file_path,
+                },
+            )
             # Use custom widget for display
             char_count = getattr(item, "total_char_count", 0)
             widget = QueueListItemWidget(display_file_path, char_count)
@@ -280,7 +321,7 @@ class QueueManager(QDialog):
         items = self.listwidget.selectedItems()
         if not items:
             return
-        from PyQt5.QtWidgets import QMessageBox
+        from PyQt6.QtWidgets import QMessageBox
 
         # Remove by index to ensure correct mapping
         rows = sorted([self.listwidget.row(item) for item in items], reverse=True)
@@ -290,10 +331,10 @@ class QueueManager(QDialog):
                 self,
                 "Confirm Remove",
                 f"Are you sure you want to remove {len(rows)} selected items from the queue?",
-                QMessageBox.Yes | QMessageBox.No,
-                QMessageBox.No,
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
+                QMessageBox.StandardButton.No,
             )
-            if reply != QMessageBox.Yes:
+            if reply != QMessageBox.StandardButton.Yes:
                 return
         for row in rows:
             if 0 <= row < len(self.queue):
@@ -302,17 +343,17 @@ class QueueManager(QDialog):
         self.update_button_states()
 
     def clear_queue(self):
-        from PyQt5.QtWidgets import QMessageBox
+        from PyQt6.QtWidgets import QMessageBox
 
         if len(self.queue) > 1:
             reply = QMessageBox.question(
                 self,
                 "Confirm Clear Queue",
                 f"Are you sure you want to clear {len(self.queue)} items from the queue?",
-                QMessageBox.Yes | QMessageBox.No,
-                QMessageBox.No,
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
+                QMessageBox.StandardButton.No,
             )
-            if reply != QMessageBox.Yes:
+            if reply != QMessageBox.StandardButton.Yes:
                 return
         self.queue.clear()
         self.listwidget.clear()
@@ -362,6 +403,13 @@ class QueueManager(QDialog):
             attrs["replace_single_newlines"] = getattr(
                 parent, "replace_single_newlines", False
             )
+            # book handler options
+            attrs["save_chapters_separately"] = getattr(
+                parent, "save_chapters_separately", None
+            )
+            attrs["merge_chapters_at_end"] = getattr(
+                parent, "merge_chapters_at_end", None
+            )
         else:
             # fallback: empty values
             attrs = {
@@ -378,11 +426,13 @@ class QueueManager(QDialog):
                     "replace_single_newlines",
                 ]
             }
+            attrs["save_chapters_separately"] = None
+            attrs["merge_chapters_at_end"] = None
         return attrs
 
     def add_files_from_paths(self, file_paths):
         from abogen.utils import calculate_text_length
-        from PyQt5.QtWidgets import QMessageBox
+        from PyQt6.QtWidgets import QMessageBox
         import os
 
         current_attrs = self.get_current_attributes()
@@ -394,7 +444,9 @@ class QueueManager(QDialog):
 
             item = QueueItem()
             item.file_name = file_path
-            item.save_base_path = file_path  # For .txt files, processing and save paths are the same
+            item.save_base_path = (
+                file_path  # For .txt files, processing and save paths are the same
+            )
             for attr, value in current_attrs.items():
                 setattr(item, attr, value)
             # Read file content and calculate total_char_count using calculate_text_length
@@ -430,6 +482,10 @@ class QueueManager(QDialog):
                     == getattr(item, "replace_single_newlines", False)
                     and getattr(queued_item, "save_base_path", None)
                     == getattr(item, "save_base_path", None)
+                    and getattr(queued_item, "save_chapters_separately", None)
+                    == getattr(item, "save_chapters_separately", None)
+                    and getattr(queued_item, "merge_chapters_at_end", None)
+                    == getattr(item, "merge_chapters_at_end", None)
                 ):
                     is_duplicate = True
                     break
@@ -447,7 +503,7 @@ class QueueManager(QDialog):
         self.update_button_states()
 
     def add_more_files(self):
-        from PyQt5.QtWidgets import QFileDialog
+        from PyQt6.QtWidgets import QFileDialog
         from abogen.utils import calculate_text_length  # import the function
 
         # Only allow .txt files
@@ -477,9 +533,9 @@ class QueueManager(QDialog):
             self.clear_button.setEnabled(bool(self.queue))
 
     def show_context_menu(self, pos):
-        from PyQt5.QtWidgets import QMenu, QAction
-        from PyQt5.QtGui import QDesktopServices
-        from PyQt5.QtCore import QUrl
+        from PyQt6.QtWidgets import QMenu
+        from PyQt6.QtGui import QAction, QDesktopServices
+        from PyQt6.QtCore import QUrl
         import os
 
         global_pos = self.listwidget.viewport().mapToGlobal(pos)
@@ -491,75 +547,129 @@ class QueueManager(QDialog):
             remove_action.triggered.connect(self.remove_item)
             menu.addAction(remove_action)
 
-            # Add Open file action
-            open_file_action = QAction("Open file", self)
-
-            def open_file():
-                from PyQt5.QtWidgets import QMessageBox
-
-                item = selected_items[0]
-                paths = item.data(Qt.UserRole)
-                if isinstance(paths, dict):
-                    file_path = paths.get('display_path', paths.get('processing_path', ''))
-                else:
-                    file_path = paths  # Fallback for old format
-                
-                # Find the queue item
-                for q in self.queue:
-                    if (getattr(q, "save_base_path", None) == file_path or 
-                        q.file_name == file_path):
-                        target_path = getattr(q, "save_base_path", None) or q.file_name
-                        if not os.path.exists(target_path):
-                            QMessageBox.warning(
-                                self, "File Not Found", f"The file does not exist."
-                            )
-                            return
-                        QDesktopServices.openUrl(QUrl.fromLocalFile(target_path))
-                        break
-
-            open_file_action.triggered.connect(open_file)
-            menu.addAction(open_file_action)
-
-            # Add Go to folder action
-            # If the queued item represents a converted document (markdown, pdf, epub)
-            # show two actions: Go to processed file (the cached .txt) and Go to input file (original source)
+            # Get paths for determining if it's a document input
             item = selected_items[0]
-            paths = item.data(Qt.UserRole)
+            paths = item.data(Qt.ItemDataRole.UserRole)
             if isinstance(paths, dict):
-                display_path = paths.get('display_path', '')
-                processing_path = paths.get('processing_path', '')
+                display_path = paths.get("display_path", "")
+                processing_path = paths.get("processing_path", "")
             else:
                 display_path = paths
                 processing_path = paths
 
-            doc_exts = ('.md', '.markdown', '.pdf', '.epub')
+            doc_exts = (".md", ".markdown", ".pdf", ".epub")
             is_document_input = (
-                isinstance(display_path, str) and display_path.lower().endswith(doc_exts)
+                isinstance(display_path, str)
+                and display_path.lower().endswith(doc_exts)
             ) or (
-                isinstance(processing_path, str) and processing_path.lower().endswith(doc_exts)
+                isinstance(processing_path, str)
+                and processing_path.lower().endswith(doc_exts)
             )
 
-            from PyQt5.QtWidgets import QMessageBox
+            # Add Open file action(s)
+            def open_file_by_path(path_label: str):
+                from PyQt6.QtWidgets import QMessageBox
+
+                p = display_path if path_label == "display" else processing_path
+                if not p:
+                    QMessageBox.warning(
+                        self, "File Not Found", "Path is not available."
+                    )
+                    return
+
+                # Find the queue item and resolve the target path
+                target_path = None
+                for q in self.queue:
+                    if (
+                        getattr(q, "save_base_path", None) == display_path
+                        or q.file_name == display_path
+                    ):
+                        if path_label == "display":
+                            target_path = (
+                                getattr(q, "save_base_path", None) or q.file_name
+                            )
+                        else:
+                            target_path = q.file_name
+                        break
+                    if (
+                        getattr(q, "save_base_path", None) == processing_path
+                        or q.file_name == processing_path
+                    ):
+                        if path_label == "display":
+                            target_path = (
+                                getattr(q, "save_base_path", None) or q.file_name
+                            )
+                        else:
+                            target_path = q.file_name
+                        break
+
+                # Fallback to the raw path if resolution failed
+                if not target_path:
+                    target_path = p
+
+                if not os.path.exists(target_path):
+                    QMessageBox.warning(
+                        self, "File Not Found", f"The file does not exist."
+                    )
+                    return
+                QDesktopServices.openUrl(QUrl.fromLocalFile(target_path))
+
+            if is_document_input:
+                # For documents, show two open options
+                open_processed_action = QAction("Open processed file", self)
+                open_processed_action.triggered.connect(
+                    lambda: open_file_by_path("processing")
+                )
+                menu.addAction(open_processed_action)
+
+                open_input_action = QAction("Open input file", self)
+                open_input_action.triggered.connect(
+                    lambda: open_file_by_path("display")
+                )
+                menu.addAction(open_input_action)
+            else:
+                # For plain text files, show single open option
+                open_file_action = QAction("Open file", self)
+                open_file_action.triggered.connect(lambda: open_file_by_path("display"))
+                menu.addAction(open_file_action)
+
+            # Add Go to folder action
+            # If the queued item represents a converted document (markdown, pdf, epub)
+            # show two actions: Go to processed file (the cached .txt) and Go to input file (original source)
+
+            from PyQt6.QtWidgets import QMessageBox
 
             def open_folder_for(path_label: str):
                 # path_label should be either 'display' or 'processing'
-                p = display_path if path_label == 'display' else processing_path
+                p = display_path if path_label == "display" else processing_path
                 if not p:
-                    QMessageBox.warning(self, "File Not Found", "Path is not available.")
+                    QMessageBox.warning(
+                        self, "File Not Found", "Path is not available."
+                    )
                     return
                 # If the stored path is the display path (original) but the actual file may be
                 # stored on the queue object differently, try to resolve via the queue entry.
                 target_path = None
                 for q in self.queue:
-                    if getattr(q, 'save_base_path', None) == display_path or q.file_name == display_path:
-                        if path_label == 'display':
-                            target_path = getattr(q, 'save_base_path', None) or q.file_name
+                    if (
+                        getattr(q, "save_base_path", None) == display_path
+                        or q.file_name == display_path
+                    ):
+                        if path_label == "display":
+                            target_path = (
+                                getattr(q, "save_base_path", None) or q.file_name
+                            )
                         else:
                             target_path = q.file_name
                         break
-                    if getattr(q, 'save_base_path', None) == processing_path or q.file_name == processing_path:
-                        if path_label == 'display':
-                            target_path = getattr(q, 'save_base_path', None) or q.file_name
+                    if (
+                        getattr(q, "save_base_path", None) == processing_path
+                        or q.file_name == processing_path
+                    ):
+                        if path_label == "display":
+                            target_path = (
+                                getattr(q, "save_base_path", None) or q.file_name
+                            )
                         else:
                             target_path = q.file_name
                         break
@@ -568,7 +678,11 @@ class QueueManager(QDialog):
                     target_path = p
 
                 if not os.path.exists(target_path):
-                    QMessageBox.warning(self, "File Not Found", f"The file does not exist: {target_path}")
+                    QMessageBox.warning(
+                        self,
+                        "File Not Found",
+                        f"The file does not exist: {target_path}",
+                    )
                     return
                 folder = os.path.dirname(target_path)
                 if os.path.exists(folder):
@@ -576,11 +690,13 @@ class QueueManager(QDialog):
 
             if is_document_input:
                 processed_action = QAction("Go to processed file", self)
-                processed_action.triggered.connect(lambda: open_folder_for('processing'))
+                processed_action.triggered.connect(
+                    lambda: open_folder_for("processing")
+                )
                 menu.addAction(processed_action)
 
                 input_action = QAction("Go to input file", self)
-                input_action.triggered.connect(lambda: open_folder_for('display'))
+                input_action.triggered.connect(lambda: open_folder_for("display"))
                 menu.addAction(input_action)
             else:
                 # Default behavior for non-document inputs: single "Go to folder" action
@@ -588,15 +704,22 @@ class QueueManager(QDialog):
 
                 def go_to_folder():
                     item = selected_items[0]
-                    paths = item.data(Qt.UserRole)
+                    paths = item.data(Qt.ItemDataRole.UserRole)
                     if isinstance(paths, dict):
-                        file_path = paths.get('display_path', paths.get('processing_path', ''))
+                        file_path = paths.get(
+                            "display_path", paths.get("processing_path", "")
+                        )
                     else:
                         file_path = paths  # Fallback for old format
                     # Find the queue item
                     for q in self.queue:
-                        if (getattr(q, "save_base_path", None) == file_path or q.file_name == file_path):
-                            target_path = getattr(q, "save_base_path", None) or q.file_name
+                        if (
+                            getattr(q, "save_base_path", None) == file_path
+                            or q.file_name == file_path
+                        ):
+                            target_path = (
+                                getattr(q, "save_base_path", None) or q.file_name
+                            )
                             if not os.path.exists(target_path):
                                 QMessageBox.warning(
                                     self, "File Not Found", f"The file does not exist."
@@ -618,7 +741,7 @@ class QueueManager(QDialog):
         clear_action = QAction("Clear Queue", self)
         clear_action.triggered.connect(self.clear_queue)
         menu.addAction(clear_action)
-        menu.exec_(global_pos)
+        menu.exec(global_pos)
 
     def accept(self):
         # Accept: keep changes
@@ -626,7 +749,7 @@ class QueueManager(QDialog):
 
     def reject(self):
         # Cancel: restore original queue
-        from PyQt5.QtWidgets import QMessageBox
+        from PyQt6.QtWidgets import QMessageBox
 
         # Warn if user changed a lot (e.g., more than 1 items difference)
         original_count = len(self._original_queue)
@@ -636,19 +759,19 @@ class QueueManager(QDialog):
                 self,
                 "Confirm Cancel",
                 f"Are you sure you want to cancel and discard all changes?",
-                QMessageBox.Yes | QMessageBox.No,
-                QMessageBox.No,
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
+                QMessageBox.StandardButton.No,
             )
-            if reply != QMessageBox.Yes:
+            if reply != QMessageBox.StandardButton.Yes:
                 return
         self.queue.clear()
         self.queue.extend(deepcopy(self._original_queue))
         super().reject()
 
     def keyPressEvent(self, event):
-        from PyQt5.QtCore import Qt
+        from PyQt6.QtCore import Qt
 
-        if event.key() == Qt.Key_Delete:
+        if event.key() == Qt.Key.Key_Delete:
             self.remove_item()
         else:
             super().keyPressEvent(event)

abogen/queued_item.py

@@ -15,3 +15,5 @@ class QueuedItem:
     total_char_count: int
     replace_single_newlines: bool = False
     save_base_path: str = None
+    save_chapters_separately: bool = None
+    merge_chapters_at_end: bool = None

abogen/utils.py

@@ -14,6 +14,7 @@ warnings.filterwarnings("ignore")
 def detect_encoding(file_path):
     import chardet
     import charset_normalizer
+
     with open(file_path, "rb") as f:
         raw_data = f.read()
     detected_encoding = None
@@ -28,6 +29,7 @@ def detect_encoding(file_path):
     encoding = detected_encoding if detected_encoding else "utf-8"
     return encoding.lower()
 
+
 def get_resource_path(package, resource):
     """
     Get the path to a resource file, with fallback to local file system.

abogen/voice_formula_gui.py

@@ -1,6 +1,6 @@
 import json
 import os
-from PyQt5.QtWidgets import (
+from PyQt6.QtWidgets import (
     QDialog,
     QVBoxLayout,
     QCheckBox,
@@ -22,12 +22,11 @@ from PyQt5.QtWidgets import (
     QFileDialog,
     QSplitter,
     QMenu,
-    QAction,
-    QComboBox,
     QApplication,
+    QComboBox,
 )
-from PyQt5.QtCore import Qt, QTimer, QPoint, QRect, QSize
-from PyQt5.QtGui import QPixmap, QIcon
+from PyQt6.QtCore import Qt, QTimer, QPoint, QRect, QSize
+from PyQt6.QtGui import QPixmap, QIcon, QAction
 from abogen.constants import (
     VOICES_INTERNAL,
     SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION,
@@ -91,7 +90,7 @@ class FlowLayout(QLayout):
         return len(self._item_list)
 
     def expandingDirections(self):
-        return Qt.Orientations(Qt.Orientation(0))
+        return Qt.Orientation(0)
 
     def hasHeightForWidth(self):
         return True
@@ -132,10 +131,14 @@ class FlowLayout(QLayout):
         for item in self._item_list:
             style = self.parentWidget().style() if self.parentWidget() else QStyle()
             layout_spacing_x = style.layoutSpacing(
-                QSizePolicy.PushButton, QSizePolicy.PushButton, Qt.Horizontal
+                QSizePolicy.ControlType.PushButton,
+                QSizePolicy.ControlType.PushButton,
+                Qt.Orientation.Horizontal,
             )
             layout_spacing_y = style.layoutSpacing(
-                QSizePolicy.PushButton, QSizePolicy.PushButton, Qt.Vertical
+                QSizePolicy.ControlType.PushButton,
+                QSizePolicy.ControlType.PushButton,
+                Qt.Orientation.Vertical,
             )
             space_x = spacing if spacing >= 0 else layout_spacing_x
             space_y = spacing if spacing >= 0 else layout_spacing_y
@@ -163,7 +166,7 @@ class VoiceMixer(QWidget):
         super().__init__()
         self.voice_name = voice_name
         self.setFixedWidth(VOICE_MIXER_WIDTH)
-        self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
+        self.setSizePolicy(QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Expanding)
 
         # TODO Set CSS for rounded corners
         # self.setObjectName("VoiceMixer")
@@ -173,7 +176,7 @@ class VoiceMixer(QWidget):
 
         # Name label at the top
         name = voice_name
-        layout.addWidget(QLabel(name), alignment=Qt.AlignCenter)
+        layout.addWidget(QLabel(name), alignment=Qt.AlignmentFlag.AlignCenter)
 
         # Voice name label with gender icon
         is_female = self.voice_name in VOICES_INTERNAL and self.voice_name[1] == "f"
@@ -181,7 +184,9 @@ class VoiceMixer(QWidget):
         # Icons layout (flag and gender)
         icons_layout = QHBoxLayout()
         icons_layout.setSpacing(3)
-        icons_layout.setAlignment(Qt.AlignCenter)  # Center the icons horizontally
+        icons_layout.setAlignment(
+            Qt.AlignmentFlag.AlignCenter
+        )  # Center the icons horizontally
 
         # Flag icon
         flag_icon_path = get_resource_path(
@@ -194,11 +199,21 @@ class VoiceMixer(QWidget):
         gender_label = QLabel()
         flag_pixmap = QPixmap(flag_icon_path)
         flag_label.setPixmap(
-            flag_pixmap.scaled(16, 16, Qt.KeepAspectRatio, Qt.SmoothTransformation)
+            flag_pixmap.scaled(
+                16,
+                16,
+                Qt.AspectRatioMode.KeepAspectRatio,
+                Qt.TransformationMode.SmoothTransformation,
+            )
         )
         gender_pixmap = QPixmap(gender_icon_path)
         gender_label.setPixmap(
-            gender_pixmap.scaled(16, 16, Qt.KeepAspectRatio, Qt.SmoothTransformation)
+            gender_pixmap.scaled(
+                16,
+                16,
+                Qt.AspectRatioMode.KeepAspectRatio,
+                Qt.TransformationMode.SmoothTransformation,
+            )
         )
         icons_layout.addWidget(flag_label)
         icons_layout.addWidget(gender_label)
@@ -210,7 +225,7 @@ class VoiceMixer(QWidget):
         self.checkbox = QCheckBox()
         self.checkbox.setChecked(initial_status)
         self.checkbox.stateChanged.connect(self.toggle_inputs)
-        layout.addWidget(self.checkbox, alignment=Qt.AlignCenter)
+        layout.addWidget(self.checkbox, alignment=Qt.AlignmentFlag.AlignCenter)
 
         # Spinbox and slider
         self.spin_box = QDoubleSpinBox()
@@ -219,26 +234,16 @@ class VoiceMixer(QWidget):
         self.spin_box.setDecimals(2)
         self.spin_box.setValue(initial_weight)
 
-        self.slider = QSlider(Qt.Vertical)
+        self.slider = QSlider(Qt.Orientation.Vertical)
         self.slider.setRange(0, 100)
         self.slider.setValue(int(initial_weight * 100))
-        self.slider.setSizePolicy(QSizePolicy.Fixed, QSizePolicy.Expanding)
+        self.slider.setSizePolicy(
+            QSizePolicy.Policy.Fixed, QSizePolicy.Policy.Expanding
+        )
         self.slider.setFixedWidth(SLIDER_WIDTH)
 
-        # Fix slider in Windows
-        if platform.system() == "Windows":
-            appstyle = QApplication.instance().style().objectName().lower()
-            if appstyle != "windowsvista":
-                # Set custom groove color for disabled state using COLORS["GREY_BACKGROUND"]
-                self.slider.setStyleSheet(
-                    f"""
-                    QSlider::groove:vertical:disabled {{
-                        background: {COLORS.get("GREY_BACKGROUND")};
-                        width: 4px;
-                        border-radius: 4px;
-                    }}
-                """
-                )
+        # Apply slider styling after widget is added to window (see showEvent)
+        self._slider_style_applied = False
 
         # Connect controls
         self.slider.valueChanged.connect(lambda val: self.spin_box.setValue(val / 100))
@@ -249,23 +254,67 @@ class VoiceMixer(QWidget):
         # Layout for slider and labels
         slider_layout = QVBoxLayout()
         slider_layout.addWidget(self.spin_box)
-        slider_layout.addWidget(QLabel("1", alignment=Qt.AlignCenter))
+        slider_layout.addWidget(QLabel("1", alignment=Qt.AlignmentFlag.AlignCenter))
 
         slider_center_layout = QHBoxLayout()
-        slider_center_layout.addWidget(self.slider, alignment=Qt.AlignHCenter)
+        slider_center_layout.addWidget(
+            self.slider, alignment=Qt.AlignmentFlag.AlignHCenter
+        )
         slider_center_layout.setContentsMargins(0, 0, 0, 0)
 
         slider_center_widget = QWidget()
         slider_center_widget.setLayout(slider_center_layout)
 
         slider_layout.addWidget(slider_center_widget, stretch=1)
-        slider_layout.addWidget(QLabel("0", alignment=Qt.AlignCenter))
+        slider_layout.addWidget(QLabel("0", alignment=Qt.AlignmentFlag.AlignCenter))
         slider_layout.setStretch(2, 1)
 
         layout.addLayout(slider_layout, stretch=1)
         self.setLayout(layout)
         self.toggle_inputs()
 
+    def showEvent(self, event):
+        super().showEvent(event)
+        # Apply slider styling once when widget is shown and has access to parent
+        if not self._slider_style_applied:
+            self._slider_style_applied = True
+            
+            # Fix slider in Windows
+            if platform.system() == "Windows":
+                appstyle = QApplication.instance().style().objectName().lower()
+                if appstyle != "windowsvista":
+                    # Set custom groove color for disabled state using COLORS["GREY_BACKGROUND"]
+                    self.slider.setStyleSheet(
+                        f"""
+                        QSlider::groove:vertical:disabled {{
+                            background: {COLORS.get("GREY_BACKGROUND")};
+                            width: 4px;
+                            border-radius: 4px;
+                        }}
+                    """
+                    )
+            else:
+                # Apply same fix for Light theme on non-Windows systems
+                # Get theme from parent window's config
+                parent_window = self.window()
+                theme = "system"
+                while parent_window:
+                    if hasattr(parent_window, "config"):
+                        theme = parent_window.config.get("theme", "system")
+                        break
+                    parent_window = parent_window.parent()
+                
+                if theme == "light":
+                    self.slider.setStyleSheet(
+                        f"""
+                        QSlider::groove:vertical:disabled {{
+                            background: {COLORS.get("GREY_BACKGROUND")};
+                            width: 4px;
+                            border-radius: 4px;
+                        }}
+                    """
+                    )
+
     def toggle_inputs(self):
         is_enabled = self.checkbox.isChecked()
         self.spin_box.setEnabled(is_enabled)
@@ -307,9 +356,11 @@ class HoverLabel(QLabel):
             """
         )
         # Make sure the entire button is clickable, not just the text
-        self.delete_button.setFocusPolicy(Qt.NoFocus)
-        self.delete_button.setAttribute(Qt.WA_TransparentForMouseEvents, False)
-        self.delete_button.setCursor(Qt.PointingHandCursor)
+        self.delete_button.setFocusPolicy(Qt.FocusPolicy.NoFocus)
+        self.delete_button.setAttribute(
+            Qt.WidgetAttribute.WA_TransparentForMouseEvents, False
+        )
+        self.delete_button.setCursor(Qt.CursorShape.PointingHandCursor)
         self.delete_button.hide()
 
     def resizeEvent(self, event):
@@ -357,7 +408,7 @@ class VoiceFormulaDialog(QDialog):
         if parent is not None and hasattr(parent, "subtitle_combo"):
             self.subtitle_combo = parent.subtitle_combo
         # Create main container layout with profile section and mixer section
-        splitter = QSplitter(Qt.Horizontal)
+        splitter = QSplitter(Qt.Orientation.Horizontal)
         # Profile section
         profile_widget = QWidget()
         profile_layout = QVBoxLayout(profile_widget)
@@ -371,8 +422,8 @@ class VoiceFormulaDialog(QDialog):
         profile_layout.addLayout(header_layout)
         # Profile list
         self.profile_list = QListWidget()
-        self.profile_list.setSelectionMode(QListWidget.SingleSelection)
-        self.profile_list.setSelectionBehavior(QListWidget.SelectRows)
+        self.profile_list.setSelectionMode(QListWidget.SelectionMode.SingleSelection)
+        self.profile_list.setSelectionBehavior(QListWidget.SelectionBehavior.SelectRows)
         self.profile_list.setStyleSheet(
             "QListWidget::item:selected { background: palette(highlight); color: palette(highlighted-text); }"
         )
@@ -388,7 +439,7 @@ class VoiceFormulaDialog(QDialog):
             idx = list(profiles.keys()).index(self.current_profile)
             self.profile_list.setCurrentRow(idx)
         profile_layout.addWidget(self.profile_list)
-        self.profile_list.setContextMenuPolicy(Qt.CustomContextMenu)
+        self.profile_list.setContextMenuPolicy(Qt.ContextMenuPolicy.CustomContextMenu)
         self.profile_list.customContextMenuRequested.connect(
             self.show_profile_context_menu
         )
@@ -409,7 +460,9 @@ class VoiceFormulaDialog(QDialog):
 
         self.setWindowTitle("Voice Mixer")
         self.setWindowFlags(
-            Qt.Window | Qt.WindowCloseButtonHint | Qt.WindowMaximizeButtonHint
+            Qt.WindowType.Window
+            | Qt.WindowType.WindowCloseButtonHint
+            | Qt.WindowType.WindowMaximizeButtonHint
         )
         self.setMinimumSize(MIN_WINDOW_WIDTH, MIN_WINDOW_HEIGHT)
         self.resize(INITIAL_WINDOW_WIDTH, INITIAL_WINDOW_HEIGHT)
@@ -468,21 +521,25 @@ class VoiceFormulaDialog(QDialog):
 
         # Separator
         separator = QFrame()
-        separator.setFrameShadow(QFrame.Sunken)
+        separator.setFrameShadow(QFrame.Shadow.Sunken)
         mixer_layout.addWidget(separator)
 
         # Voice list scroll area
         self.scroll_area = QScrollArea()
         self.scroll_area.setWidgetResizable(True)
-        self.scroll_area.setHorizontalScrollBarPolicy(Qt.ScrollBarAsNeeded)
-        self.scroll_area.setVerticalScrollBarPolicy(Qt.ScrollBarAsNeeded)
+        self.scroll_area.setHorizontalScrollBarPolicy(
+            Qt.ScrollBarPolicy.ScrollBarAsNeeded
+        )
+        self.scroll_area.setVerticalScrollBarPolicy(
+            Qt.ScrollBarPolicy.ScrollBarAsNeeded
+        )
         self.scroll_area.viewport().installEventFilter(self)
 
         self.voice_list_widget = QWidget()
         self.voice_list_layout = QHBoxLayout()
         self.voice_list_widget.setLayout(self.voice_list_layout)
         self.voice_list_widget.setSizePolicy(
-            QSizePolicy.Expanding, QSizePolicy.Expanding
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Expanding
         )
         self.scroll_area.setWidget(self.voice_list_widget)
         mixer_layout.addWidget(self.scroll_area, stretch=1)
@@ -497,6 +554,9 @@ class VoiceFormulaDialog(QDialog):
         ok_button.setDefault(True)
         ok_button.setFocus()
 
+        # Connect buttons
+        clear_all_button.clicked.connect(self.clear_all_voices)
+        ok_button.clicked.connect(self.accept)
         # Connect buttons
         clear_all_button.clicked.connect(self.clear_all_voices)
         ok_button.clicked.connect(self.accept)
@@ -533,7 +593,7 @@ class VoiceFormulaDialog(QDialog):
 
     def keyPressEvent(self, event):
         # Bind Delete key to delete_profile when a profile is selected
-        if event.key() == Qt.Key_Delete and self.profile_list.hasFocus():
+        if event.key() == Qt.Key.Key_Delete and self.profile_list.hasFocus():
             item = self.profile_list.currentItem()
             if item:
                 self.delete_profile(item)
@@ -562,10 +622,12 @@ class VoiceFormulaDialog(QDialog):
                 self,
                 "Unsaved Changes",
                 msg,
-                QMessageBox.Save | QMessageBox.Discard | QMessageBox.Cancel,
-                QMessageBox.Save,
+                QMessageBox.StandardButton.Save
+                | QMessageBox.StandardButton.Discard
+                | QMessageBox.StandardButton.Cancel,
+                QMessageBox.StandardButton.Save,
             )
-            if ret == QMessageBox.Save:
+            if ret == QMessageBox.StandardButton.Save:
                 # Save all using stored states
                 profiles = load_profiles()
                 for i in dirty_indices:
@@ -590,7 +652,7 @@ class VoiceFormulaDialog(QDialog):
                 self.update_profile_save_buttons()
                 self.update_profile_list_colors()
                 return True
-            elif ret == QMessageBox.Discard:
+            elif ret == QMessageBox.StandardButton.Discard:
                 # Discard all modifications
                 self._profile_states.clear()
                 for i in dirty_indices:
@@ -612,17 +674,19 @@ class VoiceFormulaDialog(QDialog):
         else:
             # Fallback to original logic for 0 or 1 dirty profile
             box = QMessageBox(self)
-            box.setIcon(QMessageBox.Warning)
+            box.setIcon(QMessageBox.Icon.Warning)
             box.setWindowTitle("Unsaved Changes")
             box.setText(
                 "You have unsaved changes in your profile. Do you want to save the changes?"
             )
             box.setStandardButtons(
-                QMessageBox.Save | QMessageBox.Discard | QMessageBox.Cancel
+                QMessageBox.StandardButton.Save
+                | QMessageBox.StandardButton.Discard
+                | QMessageBox.StandardButton.Cancel
             )
-            box.setDefaultButton(QMessageBox.Save)
-            ret = box.exec_()
-            if ret == QMessageBox.Save:
+            box.setDefaultButton(QMessageBox.StandardButton.Save)
+            ret = box.exec()
+            if ret == QMessageBox.StandardButton.Save:
                 for i in range(self.profile_list.count()):
                     item = self.profile_list.item(i)
                     name = item.text().lstrip("*")
@@ -636,7 +700,7 @@ class VoiceFormulaDialog(QDialog):
                 if hasattr(parent, "populate_profiles_in_voice_combo"):
                     parent.populate_profiles_in_voice_combo()
                 return True
-            elif ret == QMessageBox.Discard:
+            elif ret == QMessageBox.StandardButton.Discard:
                 profiles = load_profiles()
                 for i in range(self.profile_list.count()):
                     item = self.profile_list.item(i)
@@ -717,7 +781,7 @@ class VoiceFormulaDialog(QDialog):
         return voice_mixer
 
     def handle_voice_checkbox(self, voice_mixer, state):
-        if state == Qt.Checked:
+        if state == Qt.CheckState.Checked.value:
             self.last_enabled_voice = voice_mixer.voice_name
         self.update_weighted_sums()
 
@@ -767,7 +831,9 @@ class VoiceFormulaDialog(QDialog):
                     f'<b><span style="color:{COLORS.get("BLUE")}">{name}: {percentage:.1f}%</span></b>',
                     name,
                 )
-                voice_label.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred)
+                voice_label.setSizePolicy(
+                    QSizePolicy.Policy.Preferred, QSizePolicy.Policy.Preferred
+                )
                 voice_label.delete_button.clicked.connect(
                     lambda _, vn=name: self.disable_voice_by_name(vn)
                 )
@@ -787,7 +853,7 @@ class VoiceFormulaDialog(QDialog):
             mixer.checkbox.setChecked(False)
 
     def eventFilter(self, source, event):
-        if source is self.scroll_area.viewport() and event.type() == event.Wheel:
+        if source is self.scroll_area.viewport() and event.type() == event.Type.Wheel:
             # Skip if over an enabled slider
             if any(
                 mixer.slider.underMouse() and mixer.slider.isEnabled()
@@ -890,10 +956,10 @@ class VoiceFormulaDialog(QDialog):
             self,
             "Invalid Profiles",
             msg,
-            QMessageBox.Yes | QMessageBox.Cancel,
-            QMessageBox.Yes,
+            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.Cancel,
+            QMessageBox.StandardButton.Yes,
         )
-        if reply == QMessageBox.Yes:
+        if reply == QMessageBox.StandardButton.Yes:
             for i, name in reversed(zero):
                 self.profile_list.takeItem(i)
                 delete_profile(name)
@@ -980,8 +1046,8 @@ class VoiceFormulaDialog(QDialog):
         super().closeEvent(event)
 
     def _parse_rgba_to_qcolor(self, rgba_str):
-        from PyQt5.QtCore import Qt
-        from PyQt5.QtGui import QColor
+        from PyQt6.QtCore import Qt
+        from PyQt6.QtGui import QColor
 
         """Helper to convert 'rgba(R,G,B,A_float)' string to QColor."""
         match = re.match(r"rgba\((\d+),\s*(\d+),\s*(\d+),\s*([\d.]+)\)", rgba_str)
@@ -1136,9 +1202,12 @@ class VoiceFormulaDialog(QDialog):
                     msg += f"\nThis will overwrite an existing profile."
                 msg += "\nContinue?"
                 reply = QMessageBox.question(
-                    self, "Import Profile", msg, QMessageBox.Yes | QMessageBox.No
+                    self,
+                    "Import Profile",
+                    msg,
+                    QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
                 )
-                if reply != QMessageBox.Yes:
+                if reply != QMessageBox.StandardButton.Yes:
                     return
                 profiles.update(imported_profiles)
                 save_profiles(profiles)
@@ -1153,9 +1222,12 @@ class VoiceFormulaDialog(QDialog):
                     msg += f"\n{len(collisions)} profile(s) will be overwritten."
                 msg += "\nContinue?"
                 reply = QMessageBox.question(
-                    self, "Import Profiles", msg, QMessageBox.Yes | QMessageBox.No
+                    self,
+                    "Import Profiles",
+                    msg,
+                    QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
                 )
-                if reply != QMessageBox.Yes:
+                if reply != QMessageBox.StandardButton.Yes:
                     return
                 profiles.update(imported_profiles)
                 save_profiles(profiles)
@@ -1196,7 +1268,7 @@ class VoiceFormulaDialog(QDialog):
         menu.addAction(dup_act)
         menu.addAction(export_act)
         menu.addAction(delete_act)
-        act = menu.exec_(self.profile_list.viewport().mapToGlobal(pos))
+        act = menu.exec(self.profile_list.viewport().mapToGlobal(pos))
         if act == rename_act:
             self.rename_profile(item)
         elif act == delete_act:
@@ -1323,9 +1395,9 @@ class VoiceFormulaDialog(QDialog):
             self,
             "Delete Profile",
             f"Delete profile '{name}'?",
-            QMessageBox.Yes | QMessageBox.No,
+            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
         )
-        if reply == QMessageBox.Yes:
+        if reply == QMessageBox.StandardButton.Yes:
             delete_profile(name)
             row = self.profile_list.row(item)
             self.profile_list.takeItem(row)
@@ -1378,7 +1450,7 @@ class VoiceFormulaDialog(QDialog):
                 self.profile_list.setItemWidget(item, widget)
 
     def update_profile_list_colors(self):
-        from PyQt5.QtCore import Qt
+        from PyQt6.QtCore import Qt
 
         profiles = load_profiles()
         for i in range(self.profile_list.count()):
@@ -1386,13 +1458,14 @@ class VoiceFormulaDialog(QDialog):
             name = item.text().lstrip("*")
             if self._virtual_new_profile and name == "New profile":
                 color = self._parse_rgba_to_qcolor(COLORS.get("YELLOW_BACKGROUND"))
-                item.setData(Qt.BackgroundRole, color)
+                item.setData(Qt.ItemDataRole.BackgroundRole, color)
             elif item.text().startswith("*"):
                 color = self._parse_rgba_to_qcolor(COLORS.get("YELLOW_BACKGROUND"))
-                item.setData(Qt.BackgroundRole, color)
+                item.setData(Qt.ItemDataRole.BackgroundRole, color)
             else:
                 item.setData(
-                    Qt.BackgroundRole, self.profile_list.palette().base().color()
+                    Qt.ItemDataRole.BackgroundRole,
+                    self.profile_list.palette().base().color(),
                 )
                 weights = profiles.get(name, {}).get("voices", [])
                 total = 0
@@ -1406,7 +1479,7 @@ class VoiceFormulaDialog(QDialog):
                             total += entry[1]
                 if total == 0:
                     color = self._parse_rgba_to_qcolor(COLORS.get("RED_BACKGROUND"))
-                    item.setData(Qt.BackgroundRole, color)
+                    item.setData(Qt.ItemDataRole.BackgroundRole, color)
         self.update_profile_save_buttons()
 
     def preview_current_mix(self):

pyproject.toml

@@ -13,7 +13,7 @@ license = "MIT"
 requires-python = ">=3.10, <3.13"
 keywords = ["audiobook", "epub", "pdf", "text-to-speech", "subtitle", "tts", "kokoro", "accessibility", "book-converter", "voice-synthesis", "multilingual", "chapter-management", "subtitles", "content-creation", "media-generation"]
 dependencies = [
-    "PyQt5>=5.15.11",
+    "PyQt6>=6.10.0",
     "kokoro>=0.9.4",
     "misaki[zh]>=0.9.4",
     "ebooklib>=0.19",