TF Fix styled ASS font tracks

SCRATCHPAD.md

@@ -69,3 +69,7 @@
 ## Delete When
 
 - Delete this scratchpad once the optimization backlog is either converted into issues/work items or distilled into durable project guidance.
+
+
+
+## TODO: Review styled ASS separate handling

src/ffx/cli.py

@@ -1393,13 +1393,22 @@ def convert(ctx,
 
         from ffx.attachment_format import AttachmentFormat
 
-        if ([smd for smd in sourceMediaDescriptor.getSubtitleTracks()
-                    if smd.getCodec() == TrackCodec.ASS]
-                and [amd for amd in sourceMediaDescriptor.getAttachmentTracks()
-                    if amd.getAttachmentFormat() == AttachmentFormat.TTF]):
-            
+        styledAssSourceDetected = (
+            sourceMediaDescriptor.hasStyledAssSubtitlesWithFontAttachments()
+        )
+        if styledAssSourceDetected:
+            styledAssMessage = (
+                "Styled ASS subtitles with embedded font attachments detected; "
+                + "preserving source font attachments."
+            )
+            click.echo(styledAssMessage)
             targetFormat = ''
             targetExtension = 'mkv'
+            if context['import_subtitles']:
+                raise click.ClickException(
+                    "External subtitle import is incompatible with styled ASS "
+                    + "sources that carry embedded font attachments."
+                )
 
 
         #HINT: This is None if the filename did not match anything in database
@@ -1426,6 +1435,11 @@ def convert(ctx,
 
         else:
             targetMediaDescriptor = currentPattern.getMediaDescriptor(ctx.obj)
+            if styledAssSourceDetected:
+                targetMediaDescriptor = targetMediaDescriptor.withoutAttachmentTracks(
+                    AttachmentFormat.TTF,
+                    context=ctx.obj,
+                )
             checkUniqueDispositions(context, targetMediaDescriptor)
             currentShowDescriptor = currentPattern.getShowDescriptor(ctx.obj)
 

src/ffx/media_descriptor.py

@@ -329,6 +329,49 @@ class MediaDescriptor:
             if s.getType() == TrackType.ATTACHMENT
         ]
 
+    def hasStyledAssSubtitlesWithFontAttachments(self) -> bool:
+        return (
+            any(
+                trackDescriptor.getCodec() == TrackCodec.ASS
+                for trackDescriptor in self.getSubtitleTracks()
+            )
+            and any(
+                trackDescriptor.getAttachmentFormat() == AttachmentFormat.TTF
+                for trackDescriptor in self.getAttachmentTracks()
+            )
+        )
+
+    def withoutAttachmentTracks(
+        self,
+        attachmentFormat: AttachmentFormat | None = None,
+        context: dict | None = None,
+    ):
+        filteredTrackDescriptors = []
+        for trackDescriptor in self.__trackDescriptors:
+            if trackDescriptor.getType() == TrackType.ATTACHMENT and (
+                attachmentFormat is None
+                or trackDescriptor.getAttachmentFormat() == attachmentFormat
+            ):
+                continue
+            filteredTrackDescriptors.append(
+                trackDescriptor.clone(
+                    context=context if context is not None else self.__context
+                )
+            )
+
+        kwargs = {
+            MediaDescriptor.TAGS_KEY: dict(self.__mediaTags),
+            MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY: filteredTrackDescriptors,
+        }
+        if context is not None:
+            kwargs[MediaDescriptor.CONTEXT_KEY] = context
+        elif self.__context:
+            kwargs[MediaDescriptor.CONTEXT_KEY] = self.__context
+
+        filteredMediaDescriptor = MediaDescriptor(**kwargs)
+        filteredMediaDescriptor.reindexSubIndices()
+        return filteredMediaDescriptor
+
 
     def getImportFileTokens(self, use_sub_index: bool = True):
         """Generate ffmpeg import options for external stream files"""

tests/integration/subtrack_mapping/test_cli_bundle.py

@@ -18,6 +18,7 @@ from tests.support.ffx_bundle import (
     write_vtt,
 )
 
+from ffx.attachment_format import AttachmentFormat
 from ffx.track_type import TrackType
 
 try:
@@ -280,6 +281,72 @@ class SubtrackMappingBundleTests(unittest.TestCase):
         self.assertIn("non-existent source track #99", error_output)
         self.assertFalse(expected_output_path(self.workdir, source_filename).exists())
 
+    def test_styled_ass_source_preserves_current_font_attachments_when_pattern_count_differs(self):
+        source_filename = "styled_ass_s01e01.mkv"
+        source_path = create_source_fixture(
+            self.workdir,
+            source_filename,
+            [
+                SourceTrackSpec(TrackType.VIDEO, identity="video-0"),
+                SourceTrackSpec(TrackType.AUDIO, identity="audio-1", language="eng"),
+                SourceTrackSpec(
+                    TrackType.SUBTITLE,
+                    identity="subtitle-2",
+                    language="eng",
+                    subtitle_lines=("styled subtitle payload",),
+                ),
+                SourceTrackSpec(TrackType.ATTACHMENT, attachment_name="current.ttf"),
+            ],
+            subtitle_encoder="ass",
+        )
+
+        prepare_pattern_database(
+            self.database_path,
+            r"^styled_ass_(s[0-9]+e[0-9]+)\.mkv$",
+            [
+                PatternTrackSpec(index=0, source_index=0, track_type=TrackType.VIDEO),
+                PatternTrackSpec(index=1, source_index=1, track_type=TrackType.AUDIO),
+                PatternTrackSpec(index=2, source_index=2, track_type=TrackType.SUBTITLE),
+                PatternTrackSpec(
+                    index=3,
+                    source_index=3,
+                    track_type=TrackType.ATTACHMENT,
+                    attachment_format=AttachmentFormat.TTF,
+                ),
+                PatternTrackSpec(
+                    index=4,
+                    source_index=4,
+                    track_type=TrackType.ATTACHMENT,
+                    attachment_format=AttachmentFormat.TTF,
+                ),
+            ],
+        )
+
+        completed = run_ffx_convert(
+            self.workdir,
+            self.home_dir,
+            self.database_path,
+            "--video-encoder",
+            "copy",
+            "--no-tmdb",
+            "--no-prompt",
+            "--no-signature",
+            str(source_path),
+        )
+        self.assertCompleted(completed)
+        self.assertIn("Styled ASS subtitles", completed.stdout)
+
+        output_path = expected_output_path(self.workdir, source_filename)
+        streams = ffprobe_json(output_path)["streams"]
+
+        self.assertEqual(
+            [stream["codec_type"] for stream in streams],
+            ["video", "audio", "subtitle", "attachment"],
+        )
+        self.assertEqual(streams[2]["codec_name"], "ass")
+        self.assertEqual(streams[3]["codec_name"], "ttf")
+        self.assertEqual(get_tag(streams[3], "filename"), "current.ttf")
+
     def test_external_subtitle_file_replaces_payload_and_overrides_metadata(self):
         source_filename = "substitute_s01e01.mkv"
         self.write_config(

tests/support/ffx_bundle.py

@@ -18,6 +18,7 @@ if str(SRC_ROOT) not in sys.path:
     sys.path.insert(0, str(SRC_ROOT))
 
 
+from ffx.attachment_format import AttachmentFormat
 from ffx.audio_layout import AudioLayout
 from ffx.database import databaseContext
 from ffx.pattern_controller import PatternController
@@ -56,6 +57,7 @@ class PatternTrackSpec:
     tags: Mapping[str, str] = field(default_factory=dict)
     dispositions: tuple[TrackDisposition, ...] = ()
     audio_layout: AudioLayout = AudioLayout.LAYOUT_STEREO
+    attachment_format: AttachmentFormat = AttachmentFormat.UNKNOWN
 
 
 def make_logger(name: str) -> logging.Logger:
@@ -299,6 +301,8 @@ def prepare_pattern_database(database_path: Path, filename_pattern: str, track_s
             }
             if track.track_type == TrackType.AUDIO:
                 kwargs[TrackDescriptor.AUDIO_LAYOUT_KEY] = track.audio_layout
+            if track.track_type == TrackType.ATTACHMENT:
+                kwargs[TrackDescriptor.ATTACHMENT_FORMAT_KEY] = track.attachment_format
             track_descriptors.append(TrackDescriptor(**kwargs))
 
         pattern_id = PatternController(context).savePatternSchema(