fix: executor subtitle_writer leak + adapter Path/None-default fixes

- executor: manage subtitle_writer via ExitStack (stack.callback)
- executor: remove manual subtitle_writer.close()
- WebUI adapter: wrap source_path, output_folder, cover_image_path in Path()
- WebUI adapter: remove unused threading/time imports
- PyQt adapter: fix getattr(attr, None) or default for 4 fields

abogen/application/conversion_executor.py

@@ -134,6 +134,7 @@ def execute_conversion(
             )
             if subtitle_writer:
                 subtitle_writer.open()
+                stack.callback(subtitle_writer.close)
                 result.subtitle_paths.append(subtitle_writer.path)
 
         # Chapter directory
@@ -381,10 +382,6 @@ def execute_conversion(
             )
             events.log("Outro synthesized.")
 
-        # Close subtitle writer
-        if subtitle_writer:
-            subtitle_writer.close()
-
     # Set result metadata
     result.total_chapters = len(plan.chapters)
     result.total_segments = sum(len(ch.segments) for ch in plan.chapters)

abogen/pyqt/conversion_adapter.py

@@ -68,12 +68,12 @@ def build_conversion_request_from_thread(thread: Any) -> ConversionRequest:
         voice_profile=getattr(thread, "voice_profile", None),
         speed=thread.speed or 1.0,
         use_gpu=thread.use_gpu,
-        supertonic_total_steps=getattr(thread, "supertonic_total_steps", 5),
+        supertonic_total_steps=getattr(thread, "supertonic_total_steps", None) or 5,
         # Output Format
         output_format=thread.output_format or "wav",
         subtitle_mode=thread.subtitle_mode or "Disabled",
         subtitle_format=getattr(thread, "subtitle_format", "srt"),
-        max_subtitle_words=getattr(thread, "max_subtitle_words", 50),
+        max_subtitle_words=getattr(thread, "max_subtitle_words", None) or 50,
         # Save Options
         save_mode=thread.save_option or "save_next_to_input",
         output_folder=output_folder,
@@ -82,8 +82,8 @@ def build_conversion_request_from_thread(thread: Any) -> ConversionRequest:
         separate_chapters_format=getattr(thread, "separate_chapters_format", "wav"),
         save_as_project=getattr(thread, "save_as_project", False),
         # Timing
-        silence_between_chapters=getattr(thread, "silence_duration", 2.0),
+        silence_between_chapters=getattr(thread, "silence_duration", None) or 2.0,
-        chapter_intro_delay=getattr(thread, "chapter_intro_delay", 0.0),
+        chapter_intro_delay=getattr(thread, "chapter_intro_delay", None) or 0.0,
         # Content Processing
         replace_single_newlines=getattr(thread, "replace_single_newlines", False),
         read_title_intro=getattr(thread, "read_title_intro", False),

abogen/webui/conversion_adapter.py

@@ -14,8 +14,7 @@ never accesses Job directly.
 
 from __future__ import annotations
 
-import threading
+from pathlib import Path
-import time
 from typing import Any, Callable, Dict, List, Optional
 
 from abogen.application.conversion_request import ConversionRequest
@@ -36,7 +35,7 @@ def build_conversion_request_from_job(job: Any) -> ConversionRequest:
     """
     return ConversionRequest(
         # Source
-        source_path=job.stored_path,
+        source_path=Path(job.stored_path) if job.stored_path else None,
         original_filename=job.original_filename,
         # TTS Settings
         language=job.language or "a",
@@ -53,7 +52,7 @@ def build_conversion_request_from_job(job: Any) -> ConversionRequest:
         max_subtitle_words=job.max_subtitle_words or 50,
         # Save Options
         save_mode=job.save_mode or "save_next_to_input",
-        output_folder=job.output_folder,
+        output_folder=Path(job.output_folder) if job.output_folder else None,
         save_chapters_separately=job.save_chapters_separately,
         merge_chapters_at_end=job.merge_chapters_at_end,
         separate_chapters_format=job.separate_chapters_format or "wav",
@@ -81,7 +80,7 @@ def build_conversion_request_from_job(job: Any) -> ConversionRequest:
         # Metadata
         metadata_tags=job.metadata_tags or {},
         # Artifacts
-        cover_image_path=job.cover_image_path,
+        cover_image_path=Path(job.cover_image_path) if job.cover_image_path else None,
         cover_image_mime=job.cover_image_mime,
         generate_epub3=job.generate_epub3,
     )