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 PyQt6.QtCore import QThread, pyqtSignal, Qt, QTimer
-from PyQt5.QtWidgets import QCheckBox, QVBoxLayout, QDialog, QLabel, QDialogButtonBox
+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'] + \
+        reserved = (
-                   [f'COM{i}' for i in range(1, 10)] + \
+            ["CON", "PRN", "AUX", "NUL"]
-                   [f'LPT{i}' for i in range(1, 10)]
+            + [f"COM{i}" for i in range(1, 10)]
-        if sanitized.upper() in reserved or sanitized.upper().split('.')[0] in reserved:
+            + [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('.'):
+        if is_folder and sanitized.startswith("."):
-            sanitized = '_' + sanitized[1:]
+            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('.'):
+        if is_folder and sanitized.startswith("."):
-            sanitized = '_' + sanitized[1:]
+            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.WindowType.WindowCloseButtonHint
-            & ~Qt.WindowContextHelpButtonHint
+            & ~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(
-                            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")
+                                "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(
-                                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")
+                                    "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)
+            current_group = []
-            for i in range(0, len(processed_tokens), word_count):
+            space_count = 0
-                group = processed_tokens[i : i + word_count]
+
-                if group:
+            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 group
+                            t["text"] + (t.get("whitespace", "") or "")
+                            for t in current_group
                         )
                         subtitle_entries.append(
-                        (group[0]["start"], group[-1]["end"], text.strip())
+                            (
+                                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/gui.py

@@ -8,28 +8,30 @@ from abogen.queue_manager_gui import QueueManager
 from abogen.queued_item import QueuedItem
 import abogen.hf_tracker as hf_tracker
 import hashlib  # Added for cache path generation
-from PyQt5.QtWidgets import (
+from PyQt6.QtWidgets import (
     QApplication,
     QWidget,
     QVBoxLayout,
     QHBoxLayout,
     QPushButton,
-    QFileDialog,
-    QLabel,
-    QProgressBar,
-    QSlider,
     QComboBox,
-    QSizePolicy,
     QTextEdit,
-    QFileIconProvider,
+    QLabel,
+    QSlider,
     QMessageBox,
+    QFileDialog,
+    QProgressBar,
+    QFrame,
+    QStyleFactory,
+    QInputDialog,
+    QFileIconProvider,
+    QSizePolicy,
     QDialog,
     QCheckBox,
     QMenu,
-    QAction,
-    QActionGroup,
 )
-from PyQt5.QtCore import (
+from PyQt6.QtGui import QAction, QActionGroup
+from PyQt6.QtCore import (
     Qt,
     QUrl,
     QPoint,
@@ -42,8 +44,9 @@ from PyQt5.QtCore import (
     QSize,
     QTimer,
     QEvent,
+    QProcess,
 )
-from PyQt5.QtGui import (
+from PyQt6.QtGui import (
     QTextCursor,
     QDesktopServices,
     QIcon,
@@ -52,6 +55,7 @@ from PyQt5.QtGui import (
     QPolygon,
     QColor,
     QMovie,
+    QPalette,
 )
 from abogen.utils import (
     load_config,
@@ -95,12 +99,12 @@ class DarkTitleBarEventFilter(QObject):
         self.set_title_bar_dark_mode = set_title_bar_dark_mode_func
 
     def eventFilter(self, obj, event):
-        if event.type() == QEvent.Show:
+        if event.type() == QEvent.Type.Show:
             # Only apply to QWidget windows
             if isinstance(obj, QWidget) and obj.isWindow():
                 if self.is_windows and self.get_dark_mode():
                     self.set_title_bar_dark_mode(obj, True)
-        return False
+        return super().eventFilter(obj, event)
 
 
 class ShowWarningSignalEmitter(QObject):  # New class to handle signal emission
@@ -154,7 +158,7 @@ class InputBox(QLabel):
 
     def __init__(self, parent=None):
         super().__init__(parent)
-        self.setAlignment(Qt.AlignCenter)
+        self.setAlignment(Qt.AlignmentFlag.AlignCenter)
         self.setAcceptDrops(True)
         self.setText(
             "Drag and drop your file here or click to browse.\n(.txt, .epub, .pdf, .md)"
@@ -162,8 +166,8 @@ class InputBox(QLabel):
         self.setStyleSheet(
             f"QLabel {{ {self.STYLE_DEFAULT} }} QLabel:hover {{ {self.STYLE_DEFAULT_HOVER} }}"
         )
-        self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
+        self.setSizePolicy(QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Expanding)
-        self.setCursor(Qt.PointingHandCursor)
+        self.setCursor(Qt.CursorShape.PointingHandCursor)
 
         # Add clear button
         self.clear_btn = QPushButton("✕", self)
@@ -223,7 +227,7 @@ class InputBox(QLabel):
         pixmap = qicon.pixmap(size)
         # convert to base64 PNG
         buffer = QBuffer()
-        buffer.open(QIODevice.WriteOnly)
+        buffer.open(QIODevice.OpenModeFlag.WriteOnly)
         pixmap.save(buffer, "PNG")
         img_data = base64.b64encode(buffer.data()).decode()
 
@@ -275,7 +279,9 @@ class InputBox(QLabel):
             char_count = cached_char_count
         elif char_source_path:
             try:
-                with open(char_source_path, "r", encoding="utf-8", errors="ignore") as f:
+                with open(
+                    char_source_path, "r", encoding="utf-8", errors="ignore"
+                ) as f:
                     text = f.read()
                     cleaned_text = clean_text(text)
                     char_count = calculate_text_length(cleaned_text)
@@ -323,7 +329,8 @@ class InputBox(QLabel):
 
         # For epub/pdf files, show edit if we have a selected_file (temp txt)
         if (
-                window.selected_file_type in ["epub", "pdf", "md", "markdown", "md", "markdown"]
+            window.selected_file_type
+            in ["epub", "pdf", "md", "markdown", "md", "markdown"]
             and window.selected_file
         ):
             should_show_edit = True
@@ -356,6 +363,9 @@ class InputBox(QLabel):
         self.window().displayed_file_path = (
             None  # Reset the displayed file path when clearing input
         )
+        # Reset book handler attributes
+        self.window().save_chapters_separately = None
+        self.window().merge_chapters_at_end = None
         self.setText(
             "Drag and drop your file here or click to browse.\n(.txt, .epub, .pdf, .md)"
         )
@@ -384,7 +394,7 @@ class InputBox(QLabel):
         return f"{size:.{decimal_places}f} PB"
 
     def mousePressEvent(self, event):
-        if event.button() == Qt.LeftButton:
+        if event.button() == Qt.MouseButton.LeftButton:
             self.window().open_file_dialog()
 
     def dragEnterEvent(self, event):
@@ -446,9 +456,11 @@ class InputBox(QLabel):
                 )
                 self.set_file_info(file_path)
                 event.acceptProposedAction()
-            elif (file_path.lower().endswith(".epub")
+            elif (
+                file_path.lower().endswith(".epub")
                 or file_path.lower().endswith(".pdf")
-                  or file_path.lower().endswith((".md", ".markdown"))):
+                or file_path.lower().endswith((".md", ".markdown"))
+            ):
                 # Determine file type
                 if file_path.lower().endswith(".epub"):
                     file_type = "epub"
@@ -472,7 +484,10 @@ class InputBox(QLabel):
 
     def on_chapters_clicked(self):
         win = self.window()
-        if win.selected_file_type in ["epub", "pdf", "md", "markdown"] and win.selected_book_path:
+        if (
+            win.selected_file_type in ["epub", "pdf", "md", "markdown"]
+            and win.selected_book_path
+        ):
             # Call open_book_file which shows the dialog and updates selected_chapters
             if win.open_book_file(win.selected_book_path):
                 # Refresh the info label and button text after dialog closes
@@ -484,7 +499,10 @@ class InputBox(QLabel):
     def on_edit_clicked(self):
         win = self.window()
         # For PDFs and EPUBs, use the temporary text file
-        if win.selected_file_type in ["epub", "pdf", "md", "markdown"] and win.selected_file:
+        if (
+            win.selected_file_type in ["epub", "pdf", "md", "markdown"]
+            and win.selected_file
+        ):
             # Use the temporary .txt file that was generated
             win.open_textbox_dialog(win.selected_file)
         else:
@@ -512,9 +530,16 @@ class InputBox(QLabel):
             and cache_dir
         ):
             # Consider it cached when the file is under the cache directory and is a .txt
-            if file_to_check.endswith('.txt') and os.path.commonpath([os.path.abspath(file_to_check), os.path.abspath(cache_dir)]) == os.path.abspath(cache_dir):
+            if file_to_check.endswith(".txt") and os.path.commonpath(
+                [os.path.abspath(file_to_check), os.path.abspath(cache_dir)]
+            ) == os.path.abspath(cache_dir):
                 # Only treat as document-cache when original type was a document
-                if getattr(win, 'selected_file_type', None) in ['epub', 'pdf', 'md', 'markdown']:
+                if getattr(win, "selected_file_type", None) in [
+                    "epub",
+                    "pdf",
+                    "md",
+                    "markdown",
+                ]:
                     is_cached_doc = True
 
         if is_cached_doc:
@@ -530,8 +555,11 @@ class InputBox(QLabel):
 
             act_input = QAction("Go to input file", self)
             # Prefer displayed_file_path (original input path) then selected_book_path
-            input_path = getattr(win, 'displayed_file_path', None) or getattr(win, 'selected_book_path', None)
+            input_path = getattr(win, "displayed_file_path", None) or getattr(
+                win, "selected_book_path", None
+            )
             if input_path and os.path.exists(input_path):
+
                 def open_input():
                     folder_path = os.path.dirname(input_path)
                     QDesktopServices.openUrl(QUrl.fromLocalFile(folder_path))
@@ -542,7 +570,11 @@ class InputBox(QLabel):
 
             menu.addAction(act_input)
             # Show the menu anchored to the button
-            menu.exec_(self.go_to_folder_btn.mapToGlobal(QPoint(0, self.go_to_folder_btn.height())))
+            menu.exec(
+                self.go_to_folder_btn.mapToGlobal(
+                    QPoint(0, self.go_to_folder_btn.height())
+                )
+            )
         else:
             if (
                 file_to_check
@@ -560,7 +592,9 @@ class TextboxDialog(QDialog):
         super().__init__(parent)
         self.setWindowTitle("Enter Text")
         self.setWindowFlags(
-            Qt.Window | Qt.WindowCloseButtonHint | Qt.WindowMaximizeButtonHint
+            Qt.WindowType.Window
+            | Qt.WindowType.WindowCloseButtonHint
+            | Qt.WindowType.WindowMaximizeButtonHint
         )
         self.resize(700, 500)
 
@@ -634,16 +668,18 @@ class TextboxDialog(QDialog):
             # Check if we need to warn about overwriting a non-temporary file
             if hasattr(self, "is_non_cache_file") and self.is_non_cache_file:
                 msg_box = QMessageBox(self)
-                msg_box.setIcon(QMessageBox.Warning)
+                msg_box.setIcon(QMessageBox.Icon.Warning)
                 msg_box.setWindowTitle("File Overwrite Warning")
                 msg_box.setText(
                     f"You are about to overwrite the original file:\n{self.non_cache_file_path}"
                 )
                 msg_box.setInformativeText("Do you want to continue?")
-                msg_box.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
+                msg_box.setStandardButtons(
-                msg_box.setDefaultButton(QMessageBox.No)
+                    QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No
+                )
+                msg_box.setDefaultButton(QMessageBox.StandardButton.No)
 
-                if msg_box.exec_() != QMessageBox.Yes:
+                if msg_box.exec() != QMessageBox.StandardButton.Yes:
                     # User canceled, don't close the dialog
                     return
 
@@ -815,6 +851,7 @@ class abogen(QWidget):
         # Enable/disable subtitle options based on selected language (profile or voice)
         enable = self.selected_lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION
         self.subtitle_combo.setEnabled(enable)
+        self.subtitle_format_combo.setEnabled(enable)
         # loading gif for preview button
         loading_gif_path = get_resource_path("abogen.assets", "loading.gif")
         if loading_gif_path:
@@ -873,7 +910,7 @@ class abogen(QWidget):
         self.log_text = QTextEdit(self)
         self.log_text.setReadOnly(True)
         self.log_text.setUndoRedoEnabled(False)
-        self.log_text.setFrameStyle(QTextEdit.NoFrame)
+        self.log_text.setFrameStyle(QFrame.Shape.NoFrame)
         self.log_text.setStyleSheet("QTextEdit { border: none; }")
         self.log_text.hide()
         container_layout.addWidget(self.log_text, 1)
@@ -884,11 +921,11 @@ class abogen(QWidget):
         speed_layout = QVBoxLayout()
         speed_layout.setSpacing(2)
         speed_layout.addWidget(QLabel("Speed:", self))
-        self.speed_slider = QSlider(Qt.Horizontal, self)
+        self.speed_slider = QSlider(Qt.Orientation.Horizontal, self)
         self.speed_slider.setMinimum(10)
         self.speed_slider.setMaximum(200)
         self.speed_slider.setValue(100)
-        self.speed_slider.setTickPosition(QSlider.TicksBelow)
+        self.speed_slider.setTickPosition(QSlider.TickPosition.TicksBelow)
         self.speed_slider.setTickInterval(5)
         self.speed_slider.setSingleStep(5)
         speed_layout.addWidget(self.speed_slider)
@@ -910,7 +947,9 @@ class abogen(QWidget):
             "The first character represents the language:\n"
             '"a" => American English\n"b" => British English\n"e" => Spanish\n"f" => French\n"h" => Hindi\n"i" => Italian\n"j" => Japanese\n"p" => Brazilian Portuguese\n"z" => Mandarin Chinese\nThe second character represents the gender:\n"m" => Male\n"f" => Female'
         )
-        self.voice_combo.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Fixed)
+        self.voice_combo.setSizePolicy(
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
+        )
         voice_layout.addWidget(self.voice_combo)
         # Voice formula button
         self.btn_voice_formula_mixer = QPushButton(self)
@@ -925,11 +964,11 @@ class abogen(QWidget):
         # Play/Stop icons
         def make_icon(color, shape):
             pix = QPixmap(20, 20)
-            pix.fill(Qt.transparent)
+            pix.fill(Qt.GlobalColor.transparent)
             p = QPainter(pix)
-            p.setRenderHint(QPainter.Antialiasing)
+            p.setRenderHint(QPainter.RenderHint.Antialiasing)
             p.setBrush(QColor(*color))
-            p.setPen(Qt.NoPen)
+            p.setPen(Qt.PenStyle.NoPen)
             if shape == "play":
                 pts = [
                     pix.rect().topLeft() + QPoint(4, 2),
@@ -976,14 +1015,20 @@ class abogen(QWidget):
                 for lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION
             )
         )
-        subtitle_options = ["Disabled", "Line", "Sentence", "Sentence + Comma", "Sentence + Highlighting"] + [
+        subtitle_options = [
-            f"{i} word" if i == 1 else f"{i} words" for i in range(1, 11)
+            "Disabled",
-        ]
+            "Line",
+            "Sentence",
+            "Sentence + Comma",
+            "Sentence + Highlighting",
+        ] + [f"{i} word" if i == 1 else f"{i} words" for i in range(1, 11)]
         self.subtitle_combo.addItems(subtitle_options)
         self.subtitle_combo.setStyleSheet(
             "QComboBox { min-height: 20px; padding: 6px 12px; }"
         )
-        self.subtitle_combo.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Fixed)
+        self.subtitle_combo.setSizePolicy(
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
+        )
         self.subtitle_combo.setCurrentText(self.subtitle_mode)
         self.subtitle_combo.currentTextChanged.connect(self.on_subtitle_mode_changed)
         # Enable/disable subtitle options based on selected language (profile or voice)
@@ -1001,7 +1046,9 @@ class abogen(QWidget):
         self.format_combo.setStyleSheet(
             "QComboBox { min-height: 20px; padding: 6px 12px; }"
         )
-        self.format_combo.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Fixed)
+        self.format_combo.setSizePolicy(
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
+        )
         # Add items with display labels and underlying keys
         for key, label in [
             ("wav", "wav"),
@@ -1032,7 +1079,7 @@ class abogen(QWidget):
             "QComboBox { min-height: 20px; padding: 6px 12px; }"
         )
         self.subtitle_format_combo.setSizePolicy(
-            QSizePolicy.Expanding, QSizePolicy.Fixed
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
         )
         for value, text in SUBTITLE_FORMATS:
             self.subtitle_format_combo.addItem(text, value)
@@ -1047,7 +1094,10 @@ class abogen(QWidget):
         # If subtitle mode requires highlighting, SRT is not supported. Disable SRT item
         # and auto-switch to a compatible ASS format if SRT is currently selected.
         try:
-            if hasattr(self, "subtitle_mode") and self.subtitle_mode == "Sentence + Highlighting":
+            if (
+                hasattr(self, "subtitle_mode")
+                and self.subtitle_mode == "Sentence + Highlighting"
+            ):
                 idx_srt = self.subtitle_format_combo.findData("srt")
                 if idx_srt >= 0:
                     item = self.subtitle_format_combo.model().item(idx_srt)
@@ -1059,10 +1109,16 @@ class abogen(QWidget):
                     if new_idx >= 0:
                         self.subtitle_format_combo.setCurrentIndex(new_idx)
                         # Persist the change
-                        self.set_subtitle_format(self.subtitle_format_combo.itemData(new_idx))
+                        self.set_subtitle_format(
+                            self.subtitle_format_combo.itemData(new_idx)
+                        )
         except Exception:
             # Fail-safe: don't crash UI if model manipulation isn't supported on some platforms
             pass
+        # Enable/disable subtitle format based on selected language
+        self.subtitle_format_combo.setEnabled(
+            self.selected_lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION
+        )
         controls_layout.addLayout(subtitle_format_layout)
 
         # Replace single newlines dropdown (acts like checkbox)
@@ -1079,7 +1135,7 @@ class abogen(QWidget):
             "QComboBox { min-height: 20px; padding: 6px 12px; }"
         )
         self.replace_newlines_combo.setSizePolicy(
-            QSizePolicy.Expanding, QSizePolicy.Fixed
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
         )
         # Set initial value based on config
         self.replace_newlines_combo.setCurrentIndex(
@@ -1106,7 +1162,9 @@ class abogen(QWidget):
         self.save_combo.setStyleSheet(
             "QComboBox { min-height: 20px; padding: 6px 12px; }"
         )
-        self.save_combo.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Fixed)
+        self.save_combo.setSizePolicy(
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
+        )
         self.save_combo.setCurrentText(self.save_option)
         self.save_combo.currentTextChanged.connect(self.on_save_option_changed)
         save_layout.addWidget(self.save_combo)
@@ -1121,7 +1179,9 @@ class abogen(QWidget):
         save_path_row.addWidget(selected_folder_label)
         self.save_path_label = QLabel("", self.save_path_row_widget)
         self.save_path_label.setStyleSheet(f"QLabel {{ color: {COLORS['GREEN']}; }}")
-        self.save_path_label.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Preferred)
+        self.save_path_label.setSizePolicy(
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Preferred
+        )
         save_path_row.addWidget(self.save_path_label)
         self.save_path_row_widget.hide()  # Hide the whole row by default
         controls_layout.addWidget(self.save_path_row_widget)
@@ -1164,9 +1224,12 @@ class abogen(QWidget):
         self.btn_start.setFixedHeight(60)
         self.btn_start.clicked.connect(self.start_conversion)
         controls_layout.addWidget(self.btn_start)
+        # Add controls to a container widget
         self.controls_widget = QWidget()
         self.controls_widget.setLayout(controls_layout)
-        self.controls_widget.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Fixed)
+        self.controls_widget.setSizePolicy(
+            QSizePolicy.Policy.Preferred, QSizePolicy.Policy.Fixed
+        )
         container_layout.addWidget(self.controls_widget)
         # Progress bar
         self.progress_bar = QProgressBar(self)
@@ -1175,7 +1238,7 @@ class abogen(QWidget):
         container_layout.addWidget(self.progress_bar)
         # ETR Label
         self.etr_label = QLabel("Estimated time remaining: Calculating...", self)
-        self.etr_label.setAlignment(Qt.AlignCenter)
+        self.etr_label.setAlignment(Qt.AlignmentFlag.AlignCenter)
         self.etr_label.hide()
         container_layout.addWidget(self.etr_label)
         # Cancel button
@@ -1232,9 +1295,11 @@ class abogen(QWidget):
             )
             if not file_path:
                 return
-            if (file_path.lower().endswith(".epub")
+            if (
+                file_path.lower().endswith(".epub")
                 or file_path.lower().endswith(".pdf")
-                    or file_path.lower().endswith((".md", ".markdown"))):
+                or file_path.lower().endswith((".md", ".markdown"))
+            ):
                 # Determine file type
                 if file_path.lower().endswith(".epub"):
                     self.selected_file_type = "epub"
@@ -1270,16 +1335,16 @@ class abogen(QWidget):
         # HandlerDialog uses internal caching to avoid reprocessing the same book
         dialog = HandlerDialog(
             book_path,
-            file_type=getattr(self, 'selected_file_type', None),
+            file_type=getattr(self, "selected_file_type", None),
             checked_chapters=self.selected_chapters,
-            parent=self
+            parent=self,
         )
-        dialog.setWindowModality(Qt.NonModal)
+        dialog.setWindowModality(Qt.WindowModality.NonModal)
         dialog.setModal(False)
         dialog.show()  # We'll handle the dialog result asynchronously
 
         def on_dialog_finished(result):
-            if result != QDialog.Accepted:
+            if result != QDialog.DialogCode.Accepted:
                 return False
             chapters_text, all_checked_hrefs = dialog.get_selected_text()
             if not all_checked_hrefs:
@@ -1319,7 +1384,7 @@ class abogen(QWidget):
             if self.save_as_project:
                 # Get project directory from user
                 project_dir = QFileDialog.getExistingDirectory(
-                    self, "Select Project Folder", "", QFileDialog.ShowDirsOnly
+                    self, "Select Project Folder", "", QFileDialog.Option.ShowDirsOnly
                 )
                 if not project_dir:
                     # User cancelled, fallback to cache
@@ -1445,7 +1510,7 @@ class abogen(QWidget):
                     dialog.non_cache_file_path = edit_file
             except Exception:
                 pass
-        if dialog.exec_() == QDialog.Accepted:
+        if dialog.exec() == QDialog.DialogCode.Accepted:
             text = dialog.get_text()
             if not text.strip():
                 self._show_error_message_box("Textbox Error", "Text cannot be empty.")
@@ -1494,9 +1559,11 @@ class abogen(QWidget):
         # Enable/disable subtitle options based on language
         if self.selected_lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION:
             self.subtitle_combo.setEnabled(True)
+            self.subtitle_format_combo.setEnabled(True)
             self.subtitle_mode = self.subtitle_combo.currentText()
         else:
             self.subtitle_combo.setEnabled(False)
+            self.subtitle_format_combo.setEnabled(False)
 
     def on_voice_combo_changed(self, index):
         data = self.voice_combo.itemData(index)
@@ -1521,6 +1588,9 @@ class abogen(QWidget):
             self.subtitle_combo.setEnabled(
                 self.selected_lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION
             )
+            self.subtitle_format_combo.setEnabled(
+                self.selected_lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION
+            )
         else:
             self.mixed_voice_state = None
             self.selected_profile_name = None
@@ -1531,9 +1601,11 @@ class abogen(QWidget):
             save_config(self.config)
             if self.selected_lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION:
                 self.subtitle_combo.setEnabled(True)
+                self.subtitle_format_combo.setEnabled(True)
                 self.subtitle_mode = self.subtitle_combo.currentText()
             else:
                 self.subtitle_combo.setEnabled(False)
+                self.subtitle_format_combo.setEnabled(False)
 
     def update_subtitle_combo_for_profile(self, profile_name):
         from abogen.voice_profiles import load_profiles
@@ -1542,6 +1614,7 @@ class abogen(QWidget):
         lang = entry.get("language") if isinstance(entry, dict) else None
         enable = lang in SUPPORTED_LANGUAGES_FOR_SUBTITLE_GENERATION
         self.subtitle_combo.setEnabled(enable)
+        self.subtitle_format_combo.setEnabled(enable)
 
     def populate_profiles_in_voice_combo(self):
         # preserve current voice or profile
@@ -1605,7 +1678,7 @@ class abogen(QWidget):
         at_bottom = sb.value() == sb.maximum()
 
         cursor = txt.textCursor()
-        cursor.movePosition(QTextCursor.End)
+        cursor.movePosition(QTextCursor.MoveOperation.End)
 
         fmt = cursor.charFormat()
         if isinstance(message, tuple):
@@ -1624,7 +1697,7 @@ class abogen(QWidget):
             end = doc.findBlockByNumber(excess).position()
             trim_cursor = QTextCursor(doc)
             trim_cursor.setPosition(start)
-            trim_cursor.setPosition(end, QTextCursor.KeepAnchor)
+            trim_cursor.setPosition(end, QTextCursor.MoveMode.KeepAnchor)
             trim_cursor.removeSelectedText()
 
         if at_bottom:
@@ -1715,7 +1788,9 @@ class abogen(QWidget):
         if self.selected_file_type in ["epub", "pdf", "md", "markdown"]:
             file_to_queue = self.selected_file
             # Use the original file path for save location
-            save_base_path = self.displayed_file_path if self.displayed_file_path else file_to_queue
+            save_base_path = (
+                self.displayed_file_path if self.displayed_file_path else file_to_queue
+            )
         else:
             file_to_queue = (
                 self.displayed_file_path
@@ -1743,6 +1818,8 @@ class abogen(QWidget):
             total_char_count=self.char_count,
             replace_single_newlines=self.replace_single_newlines,
             save_base_path=save_base_path,
+            save_chapters_separately=getattr(self, "save_chapters_separately", None),
+            merge_chapters_at_end=getattr(self, "merge_chapters_at_end", None),
         )
 
         # Prevent adding duplicate items to the queue
@@ -1760,6 +1837,10 @@ class abogen(QWidget):
                 == item_queue.replace_single_newlines
                 and getattr(queued_item, "save_base_path", None)
                 == item_queue.save_base_path
+                and getattr(queued_item, "save_chapters_separately", None)
+                == item_queue.save_chapters_separately
+                and getattr(queued_item, "merge_chapters_at_end", None)
+                == item_queue.merge_chapters_at_end
             ):
                 QMessageBox.warning(
                     self, "Duplicate Item", "This item is already in the queue."
@@ -1779,10 +1860,10 @@ class abogen(QWidget):
                 self,
                 "Confirm Clear Queue",
                 f"Are you sure you want to clear {len(self.queued_items)} items from the queue?",
-                QMessageBox.Yes | QMessageBox.No,
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
-                QMessageBox.No,
+                QMessageBox.StandardButton.No,
             )
-            if reply != QMessageBox.Yes:
+            if reply != QMessageBox.StandardButton.Yes:
                 return
         self.queued_items = []
         self.enable_disable_queue_buttons()
@@ -1790,7 +1871,7 @@ class abogen(QWidget):
     def manage_queue(self):
         # show a dialog to manage the queue
         dialog = QueueManager(self, self.queued_items)
-        if dialog.exec_() == QDialog.Accepted:
+        if dialog.exec() == QDialog.DialogCode.Accepted:
             self.queued_items = dialog.get_queue()
             # re-enable/disable buttons based on queue state
             self.enable_disable_queue_buttons()
@@ -1820,7 +1901,9 @@ class abogen(QWidget):
                 queued_item, "replace_single_newlines", False
             )
             # Restore the original file path for save location
-            self.displayed_file_path = queued_item.save_base_path or queued_item.file_name
+            self.displayed_file_path = (
+                queued_item.save_base_path or queued_item.file_name
+            )
             self.start_conversion(from_queue=True)
         else:
             # Queue finished, reset index
@@ -2057,7 +2140,7 @@ class abogen(QWidget):
         dialog.setLayout(layout)
         dialog.setMinimumSize(400, 300)
         dialog.setSizeGripEnabled(True)  # Allow resizing
-        dialog.exec_()
+        dialog.exec()
 
     def on_conversion_finished(self, message, output_path):
         prevent_sleep_end()
@@ -2516,14 +2599,14 @@ class abogen(QWidget):
 
     def _show_error_message_box(self, title, message):
         box = QMessageBox(self)
-        box.setIcon(QMessageBox.Critical)
+        box.setIcon(QMessageBox.Icon.Critical)
         box.setWindowTitle(title)
         box.setText(message)
         copy_btn = QPushButton("Copy")
-        box.addButton(copy_btn, QMessageBox.ActionRole)
+        box.addButton(copy_btn, QMessageBox.ButtonRole.ActionRole)
-        box.addButton(QMessageBox.Ok)
+        box.addButton(QMessageBox.StandardButton.Ok)
         copy_btn.clicked.connect(lambda: QApplication.clipboard().setText(message))
-        box.exec_()
+        box.exec()
 
     def _show_preview_error_box(self, msg):
         self._show_error_message_box("Preview Error", f"Preview error: {msg}")
@@ -2551,14 +2634,16 @@ class abogen(QWidget):
     def cancel_conversion(self):
         if self.is_converting:
             box = QMessageBox(self)
-            box.setIcon(QMessageBox.Warning)
+            box.setIcon(QMessageBox.Icon.Warning)
             box.setWindowTitle("Cancel Conversion")
             box.setText(
                 "A conversion is currently running. Are you sure you want to cancel?"
             )
-            box.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
+            box.setStandardButtons(
-            box.setDefaultButton(QMessageBox.No)
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No
-            if box.exec_() != QMessageBox.Yes:
+            )
+            box.setDefaultButton(QMessageBox.StandardButton.No)
+            if box.exec() != QMessageBox.StandardButton.Yes:
                 return
         try:
             if (
@@ -2626,7 +2711,9 @@ class abogen(QWidget):
                     new_idx = self.subtitle_format_combo.findData("ass_centered_narrow")
                     if new_idx >= 0:
                         self.subtitle_format_combo.setCurrentIndex(new_idx)
-                        self.set_subtitle_format(self.subtitle_format_combo.itemData(new_idx))
+                        self.set_subtitle_format(
+                            self.subtitle_format_combo.itemData(new_idx)
+                        )
             else:
                 # Re-enable SRT option when not in highlighting mode
                 if idx_srt >= 0:
@@ -2643,7 +2730,7 @@ class abogen(QWidget):
         save_config(self.config)
 
     def on_gpu_setting_changed(self, state):
-        self.use_gpu = state == Qt.Checked
+        self.use_gpu = state == Qt.CheckState.Checked.value
         self.config["use_gpu"] = self.use_gpu
         save_config(self.config)
 
@@ -2660,14 +2747,16 @@ class abogen(QWidget):
     def closeEvent(self, event):
         if self.is_converting:
             box = QMessageBox(self)
-            box.setIcon(QMessageBox.Warning)
+            box.setIcon(QMessageBox.Icon.Warning)
             box.setWindowTitle("Conversion in Progress")
             box.setText(
                 "A conversion is currently running. Are you sure you want to exit?"
             )
-            box.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
+            box.setStandardButtons(
-            box.setDefaultButton(QMessageBox.No)
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No
-            if box.exec_() == QMessageBox.Yes:
+            )
+            box.setDefaultButton(QMessageBox.StandardButton.No)
+            if box.exec() == QMessageBox.StandardButton.Yes:
                 self.cleanup_conversion_thread()
                 event.accept()
             else:
@@ -2681,10 +2770,10 @@ class abogen(QWidget):
         from abogen.conversion import ChapterOptionsDialog
 
         dialog = ChapterOptionsDialog(chapter_count, parent=self)
-        dialog.setWindowModality(Qt.ApplicationModal)
+        dialog.setWindowModality(Qt.WindowModality.ApplicationModal)
 
         # If dialog is accepted, pass the options to the conversion thread
-        if dialog.exec_() == QDialog.Accepted:
+        if dialog.exec() == QDialog.DialogCode.Accepted:
             options = dialog.get_options()
             if (
                 hasattr(self, "conversion_thread")
@@ -2696,8 +2785,6 @@ class abogen(QWidget):
             self.cancel_conversion()
 
     def apply_theme(self, theme):
-        from PyQt5.QtGui import QPalette, QColor
-        from PyQt5.QtWidgets import QStyleFactory
 
         app = QApplication.instance()
         is_windows = platform.system() == "Windows"
@@ -2981,7 +3068,7 @@ class abogen(QWidget):
         about_action.triggered.connect(self.show_about_dialog)
         menu.addAction(about_action)
 
-        menu.exec_(self.settings_btn.mapToGlobal(QPoint(0, self.settings_btn.height())))
+        menu.exec(self.settings_btn.mapToGlobal(QPoint(0, self.settings_btn.height())))
 
     def toggle_replace_single_newlines(self, enabled):
         self.replace_single_newlines = enabled
@@ -2989,7 +3076,7 @@ class abogen(QWidget):
         save_config(self.config)
 
     def restart_app(self):
-        from PyQt5.QtCore import QProcess
+
         import sys
 
         exe = sys.executable
@@ -3022,10 +3109,10 @@ class abogen(QWidget):
             self,
             "Restart Required",
             message,
-            QMessageBox.Yes | QMessageBox.No,
+            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
-            QMessageBox.No,
+            QMessageBox.StandardButton.No,
         )
-        if reply == QMessageBox.Yes:
+        if reply == QMessageBox.StandardButton.Yes:
             self.config["disable_kokoro_internet"] = disabled
             save_config(self.config)
             try:
@@ -3040,10 +3127,10 @@ class abogen(QWidget):
             self,
             "Reset Settings",
             "This will reset all settings to their default values and restart the application.\n\nDo you want to continue?",
-            QMessageBox.Yes | QMessageBox.No,
+            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
-            QMessageBox.No,
+            QMessageBox.StandardButton.No,
         )
-        if reply == QMessageBox.Yes:
+        if reply == QMessageBox.StandardButton.Yes:
             from abogen.utils import get_user_config_path
 
             config_path = get_user_config_path()
@@ -3204,9 +3291,9 @@ Categories=AudioVideo;Audio;Utility;
                     self,
                     "Install Application Entry",
                     "Install application entry for current user?",
-                    QMessageBox.Yes | QMessageBox.No,
+                    QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
                 )
-                if reply == QMessageBox.Yes:
+                if reply == QMessageBox.StandardButton.Yes:
                     import shutil
 
                     user_app_dir = os.path.expanduser("~/.local/share/applications")
@@ -3266,12 +3353,11 @@ Categories=AudioVideo;Audio;Utility;
                     initial_state = entry.get("voices", [])
                 else:
                     initial_state = entry
-            else:
+                    self.selected_lang = entry[0][0] if entry and entry[0] else None
-                initial_state = []
         dialog = VoiceFormulaDialog(
             self, initial_state=initial_state, selected_profile=selected_profile
         )
-        if dialog.exec_() == QDialog.Accepted:
+        if dialog.exec() == QDialog.DialogCode.Accepted:
             if dialog.current_profile:
                 self.selected_profile_name = dialog.current_profile
                 self.config["selected_profile_name"] = dialog.current_profile
@@ -3292,7 +3378,9 @@ Categories=AudioVideo;Audio;Utility;
         # Create custom dialog
         dialog = QDialog(self)
         dialog.setWindowTitle(f"About {PROGRAM_NAME}")
-        dialog.setWindowFlags(dialog.windowFlags() & ~Qt.WindowContextHelpButtonHint)
+        dialog.setWindowFlags(
+            dialog.windowFlags() & ~Qt.WindowType.WindowContextHelpButtonHint
+        )
         dialog.setFixedSize(400, 320)  # Increased height for new button
 
         layout = QVBoxLayout(dialog)
@@ -3314,7 +3402,7 @@ Categories=AudioVideo;Audio;Utility;
         title_label = QLabel(
             f"<h1 style='margin-bottom: 0;'>{PROGRAM_NAME} <span style='font-size: 12px; font-weight: normal; color: #666;'>v{VERSION}</span></h1><h3 style='margin-top: 5px;'>Audiobook Generator</h3>"
         )
-        title_label.setTextFormat(Qt.RichText)
+        title_label.setTextFormat(Qt.TextFormat.RichText)
         header_layout.addWidget(title_label, 1)
         layout.addLayout(header_layout)
 
@@ -3323,7 +3411,7 @@ Categories=AudioVideo;Audio;Utility;
             f"<p>{PROGRAM_DESCRIPTION}</p>"
             "<p>Visit the GitHub repository for updates, documentation, and to report issues.</p>"
         )
-        desc_label.setTextFormat(Qt.RichText)
+        desc_label.setTextFormat(Qt.TextFormat.RichText)
         desc_label.setWordWrap(True)
         layout.addWidget(desc_label)
 
@@ -3346,7 +3434,7 @@ Categories=AudioVideo;Audio;Utility;
         close_btn.setFixedHeight(32)
         layout.addWidget(close_btn)
 
-        dialog.exec_()
+        dialog.exec()
 
     def manual_check_for_updates(self):
         """Manually check for updates and always show result"""
@@ -3359,7 +3447,7 @@ Categories=AudioVideo;Audio;Utility;
 
         def show_update_message(remote_version, local_version):
             msg_box = QMessageBox(self)
-            msg_box.setIcon(QMessageBox.Information)
+            msg_box.setIcon(QMessageBox.Icon.Information)
             msg_box.setWindowTitle("Update Available")
             msg_box.setText(
                 f"A new version of {PROGRAM_NAME} is available! ({local_version} > {remote_version})"
@@ -3371,9 +3459,11 @@ Categories=AudioVideo;Audio;Utility;
                 "Alternatively, visit the GitHub repository for more information. "
                 "Would you like to view the changelog?"
             )
-            msg_box.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
+            msg_box.setStandardButtons(
-            msg_box.setDefaultButton(QMessageBox.Yes)
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No
-            if msg_box.exec_() == QMessageBox.Yes:
+            )
+            msg_box.setDefaultButton(QMessageBox.StandardButton.Yes)
+            if msg_box.exec() == QMessageBox.StandardButton.Yes:
                 try:
                     QDesktopServices.openUrl(QUrl(GITHUB_URL + "/releases/latest"))
                 except Exception:
@@ -3455,7 +3545,7 @@ Categories=AudioVideo;Audio;Utility;
 
             # Create a custom message box with checkbox
             msg_box = QMessageBox(self)
-            msg_box.setIcon(QMessageBox.Question)
+            msg_box.setIcon(QMessageBox.Icon.Question)
             msg_box.setWindowTitle("Clear Cache Files")
 
             msg_text = f"Found {file_count} cache file{'s' if file_count != 1 else ''} in the {PROGRAM_NAME} cache folder."
@@ -3474,10 +3564,12 @@ Categories=AudioVideo;Audio;Utility;
             msg_box.setCheckBox(preview_cache_checkbox)
 
             # Add buttons
-            msg_box.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
+            msg_box.setStandardButtons(
-            msg_box.setDefaultButton(QMessageBox.Yes)
+                QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No
+            )
+            msg_box.setDefaultButton(QMessageBox.StandardButton.Yes)
 
-            if msg_box.exec_() != QMessageBox.Yes:
+            if msg_box.exec() != QMessageBox.StandardButton.Yes:
                 return
 
             # Delete the text files
@@ -3522,7 +3614,7 @@ Categories=AudioVideo;Audio;Utility;
 
     def set_max_log_lines(self):
         """Open a dialog to set the maximum lines in the log window."""
-        from PyQt5.QtWidgets import QInputDialog
+        from PyQt6.QtWidgets import QInputDialog
 
         value, ok = QInputDialog.getInt(
             self,
@@ -3545,7 +3637,7 @@ Categories=AudioVideo;Audio;Utility;
 
     def set_max_subtitle_words(self):
         """Open a dialog to set the maximum words per subtitle"""
-        from PyQt5.QtWidgets import QInputDialog
+        from PyQt6.QtWidgets import QInputDialog
 
         current_value = self.config.get("max_subtitle_words", 50)
 
@@ -3574,7 +3666,6 @@ Categories=AudioVideo;Audio;Utility;
 
     def set_silence_between_chapters(self):
         """Open a dialog to set the silence duration between chapters"""
-        from PyQt5.QtWidgets import QInputDialog, QDialog
 
         current_value = self.config.get("silence_duration", 2.0)
 
@@ -3583,14 +3674,14 @@ Categories=AudioVideo;Audio;Utility;
         dlg.setLabelText(
             "Enter the duration of silence\nbetween chapters (in seconds):"
         )
-        dlg.setInputMode(QInputDialog.DoubleInput)
+        dlg.setInputMode(QInputDialog.InputMode.DoubleInput)
         dlg.setDoubleDecimals(1)
         dlg.setDoubleMinimum(0.0)
         dlg.setDoubleMaximum(60.0)
         dlg.setDoubleValue(current_value)
         dlg.setDoubleStep(0.1)  # <-- set step to 0.1
 
-        if dlg.exec_() == QDialog.Accepted:
+        if dlg.exec() == QDialog.DialogCode.Accepted:
             value = dlg.doubleValue()
             # Round to one decimal to avoid floating-point representation noise
             value = round(value, 1)
@@ -3606,6 +3697,7 @@ Categories=AudioVideo;Audio;Utility;
                 "Setting Saved",
                 f"Silence duration between chapters set to {value:.1f} seconds.",
             )
+
     def set_separate_chapters_format(self, fmt):
         """Set the format for separate chapters audio files."""
         self.separate_chapters_format = fmt

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
+    from PyQt6.QtCore import QLibraryInfo
-    plugins = QLibraryInfo.location(QLibraryInfo.PluginsPath)
+
+    # 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 PyQt6.QtWidgets import QApplication
-from PyQt5.QtGui import QIcon
+from PyQt6.QtGui import QIcon
-from PyQt5.QtCore import qInstallMessageHandler, QtMsgType
+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):
+    def __init__(self, text):
-        super().__init__(text, parent)
+        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.setAlignment(
-        char_label.setSizePolicy(QSizePolicy.Minimum, QSizePolicy.Preferred)
+            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
+            display_file_path = (
-            processing_file_path = os.path.normpath(processing_file_path) if processing_file_path else processing_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, {
+            list_item.setData(
-                'display_path': display_file_path,
+                Qt.ItemDataRole.UserRole,
-                'processing_path': processing_file_path
+                {
-            })
+                    "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.StandardButton.Yes | QMessageBox.StandardButton.No,
-                QMessageBox.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.StandardButton.Yes | QMessageBox.StandardButton.No,
-                QMessageBox.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 PyQt6.QtWidgets import QMenu
-        from PyQt5.QtGui import QDesktopServices
+        from PyQt6.QtGui import QAction, QDesktopServices
-        from PyQt5.QtCore import QUrl
+        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
+            # Get paths for determining if it's a document input
-            open_file_action = QAction("Open file", self)
-
-            def open_file():
-                from PyQt5.QtWidgets import QMessageBox
-
             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', ''))
+                display_path = paths.get("display_path", "")
+                processing_path = paths.get("processing_path", "")
             else:
-                    file_path = paths  # Fallback for old format
+                display_path = paths
+                processing_path = paths
 
-                # Find the queue item
+            doc_exts = (".md", ".markdown", ".pdf", ".epub")
+            is_document_input = (
+                isinstance(display_path, str)
+                and display_path.lower().endswith(doc_exts)
+            ) or (
+                isinstance(processing_path, str)
+                and processing_path.lower().endswith(doc_exts)
+            )
+
+            # 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) == file_path or 
+                    if (
-                        q.file_name == file_path):
+                        getattr(q, "save_base_path", None) == display_path
-                        target_path = getattr(q, "save_base_path", None) or q.file_name
+                        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))
-                        break
 
-            open_file_action.triggered.connect(open_file)
+            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)
-            item = selected_items[0]
-            paths = item.data(Qt.UserRole)
-            if isinstance(paths, dict):
-                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')
+            from PyQt6.QtWidgets import QMessageBox
-            is_document_input = (
-                isinstance(display_path, str) and display_path.lower().endswith(doc_exts)
-            ) or (
-                isinstance(processing_path, str) and processing_path.lower().endswith(doc_exts)
-            )
-
-            from PyQt5.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 (
-                        if path_label == 'display':
+                        getattr(q, "save_base_path", None) == display_path
-                            target_path = getattr(q, 'save_base_path', None) or q.file_name
+                        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 (
-                        if path_label == 'display':
+                        getattr(q, "save_base_path", None) == processing_path
-                            target_path = getattr(q, 'save_base_path', None) or q.file_name
+                        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):
+                        if (
-                            target_path = getattr(q, "save_base_path", None) or q.file_name
+                            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.StandardButton.Yes | QMessageBox.StandardButton.No,
-                QMessageBox.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 PyQt6.QtCore import Qt, QTimer, QPoint, QRect, QSize
-from PyQt5.QtGui import QPixmap, QIcon
+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()
@@ -219,12 +234,51 @@ 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)
 
+        # 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))
+        self.spin_box.valueChanged.connect(
+            lambda val: self.slider.setValue(int(val * 100))
+        )
+
+        # Layout for slider and labels
+        slider_layout = QVBoxLayout()
+        slider_layout.addWidget(self.spin_box)
+        slider_layout.addWidget(QLabel("1", alignment=Qt.AlignmentFlag.AlignCenter))
+
+        slider_center_layout = QHBoxLayout()
+        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.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()
@@ -239,33 +293,28 @@ class VoiceMixer(QWidget):
                         }}
                     """
                     )
+            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()
                 
-        # Connect controls
+                if theme == "light":
-        self.slider.valueChanged.connect(lambda val: self.spin_box.setValue(val / 100))
+                    self.slider.setStyleSheet(
-        self.spin_box.valueChanged.connect(
+                        f"""
-            lambda val: self.slider.setValue(int(val * 100))
+                        QSlider::groove:vertical:disabled {{
+                            background: {COLORS.get("GREY_BACKGROUND")};
+                            width: 4px;
+                            border-radius: 4px;
+                        }}
+                    """
                     )
 
-        # Layout for slider and labels
-        slider_layout = QVBoxLayout()
-        slider_layout.addWidget(self.spin_box)
-        slider_layout.addWidget(QLabel("1", alignment=Qt.AlignCenter))
-
-        slider_center_layout = QHBoxLayout()
-        slider_center_layout.addWidget(self.slider, alignment=Qt.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.setStretch(2, 1)
-
-        layout.addLayout(slider_layout, stretch=1)
-        self.setLayout(layout)
-        self.toggle_inputs()
-
     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.setFocusPolicy(Qt.FocusPolicy.NoFocus)
-        self.delete_button.setAttribute(Qt.WA_TransparentForMouseEvents, False)
+        self.delete_button.setAttribute(
-        self.delete_button.setCursor(Qt.PointingHandCursor)
+            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.setSelectionMode(QListWidget.SelectionMode.SingleSelection)
-        self.profile_list.setSelectionBehavior(QListWidget.SelectRows)
+        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.setHorizontalScrollBarPolicy(
-        self.scroll_area.setVerticalScrollBarPolicy(Qt.ScrollBarAsNeeded)
+            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.StandardButton.Save
-                QMessageBox.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)
+            box.setDefaultButton(QMessageBox.StandardButton.Save)
-            ret = box.exec_()
+            ret = box.exec()
-            if ret == QMessageBox.Save:
+            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.StandardButton.Yes | QMessageBox.StandardButton.Cancel,
-            QMessageBox.Yes,
+            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 PyQt6.QtCore import Qt
-        from PyQt5.QtGui import QColor
+        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",