Merge branch 'refactor/domain-io-extraction'

Extract all I/O (subprocess, filesystem, YAML loading) from the domain
layer via ports/adapters. domain/subtitles/ now has zero imports from
infrastructure/. The remaining domain → infra leak (release knowledge
loaded at import time) is documented in tech-debt for a dedicated branch.

CHANGELOG.md

@@ -112,6 +112,48 @@ callers).
 
 ### Internal
 
+- **Domain I/O extraction** (`refactor/domain-io-extraction`): the domain
+  layer no longer performs subprocess calls, filesystem scans, or YAML
+  loading. Achieved in a series of focused commits:
+  - **Knowledge YAML loaders moved to infrastructure**:
+    `alfred/domain/release/knowledge.py`,
+    `alfred/domain/shared/knowledge/language_registry.py`, and
+    `alfred/domain/subtitles/knowledge/{base,loader}.py` relocated to
+    `alfred/infrastructure/knowledge/`. Re-exports were dropped — callers
+    import directly from the new location.
+  - **`MediaProber` and `FilesystemScanner` Protocol ports** introduced at
+    `alfred/domain/shared/ports/` with frozen-dataclass DTOs
+    (`SubtitleStreamInfo`, `FileEntry`). `SubtitleIdentifier` and
+    `PatternDetector` are now constructor-injected with concrete adapters
+    (`FfprobeMediaProber` wrapping `subprocess.run(ffprobe)` and
+    `PathlibFilesystemScanner` wrapping `pathlib`). No more direct
+    `subprocess`/`pathlib` usage from the subtitle domain services.
+  - **Live filesystem methods removed from VOs and entities**:
+    `FilePath.exists()` / `.is_file()` / `.is_dir()` deleted —
+    `FilePath` is now a pure address VO. `Movie.has_file()` and
+    `Episode.is_downloaded()` dropped. Callers either rely on a prior
+    detection step or use try/except over pre-checks (eliminates
+    TOCTOU races).
+  - **`SubtitlePlacer` moved to the application layer** at
+    `alfred/application/subtitles/placer.py` — it performs `os.link`
+    I/O, which doesn't belong in the domain. Pre-checks replaced with
+    try/except for `FileNotFoundError`/`FileExistsError`.
+  - **`SubtitleRuleSet.resolve()` no longer reaches into the knowledge
+    base**: the implicit `DEFAULT_RULES()` helper is gone, replaced by
+    an explicit `default_rules: SubtitleMatchingRules` parameter. The
+    `ManageSubtitles` use case loads defaults from the KB once and
+    passes them in.
+  - **`SubtitleKnowledge` Protocol port** at
+    `alfred/domain/subtitles/ports/knowledge.py` declares the read-only
+    query surface domain services consume (7 methods:
+    `known_extensions`, `format_for_extension`, `language_for_token`,
+    `is_known_lang_token`, `type_for_token`, `is_known_type_token`,
+    `patterns`). `SubtitleIdentifier` and `PatternDetector` depend on
+    this Protocol instead of the concrete `SubtitleKnowledgeBase` from
+    infrastructure — `domain/subtitles/` now has zero imports from
+    `infrastructure/`. The remaining domain → infra leak
+    (`domain/release/` loading separator YAML at import-time) is
+    documented in tech-debt and scheduled for its own branch.
 - **`to_dot_folder_name(title)` helper** in
   `alfred/domain/shared/value_objects.py` — extracts the
   `re.sub(r"[^\w\s\.\-]", "", title).replace(" ", ".")` pattern that was

alfred/application/filesystem/manage_subtitles.py

@@ -5,19 +5,21 @@ from pathlib import Path
 
 from alfred.domain.shared.value_objects import ImdbId
 from alfred.domain.subtitles.entities import SubtitleCandidate
-from alfred.domain.subtitles.knowledge.base import SubtitleKnowledgeBase
-from alfred.domain.subtitles.knowledge.loader import KnowledgeLoader
 from alfred.domain.subtitles.services.identifier import SubtitleIdentifier
 from alfred.domain.subtitles.services.matcher import SubtitleMatcher
 from alfred.domain.subtitles.services.pattern_detector import PatternDetector
-from alfred.domain.subtitles.services.placer import (
+from alfred.application.subtitles.placer import (
     PlacedTrack,
     SubtitlePlacer,
     _build_dest_name,
 )
 from alfred.domain.subtitles.services.utils import available_subtitles
 from alfred.domain.subtitles.value_objects import ScanStrategy
+from alfred.infrastructure.filesystem.scanner import PathlibFilesystemScanner
+from alfred.infrastructure.knowledge.subtitles.base import SubtitleKnowledgeBase
+from alfred.infrastructure.knowledge.subtitles.loader import KnowledgeLoader
 from alfred.infrastructure.persistence.context import get_memory
+from alfred.infrastructure.probe.ffprobe_prober import FfprobeMediaProber
 from alfred.infrastructure.subtitle.metadata_store import SubtitleMetadataStore
 from alfred.infrastructure.subtitle.rule_repository import RuleSetRepository
 
@@ -91,13 +93,21 @@ class ManageSubtitlesUseCase:
             )
 
         kb = SubtitleKnowledgeBase(KnowledgeLoader())
+        prober = FfprobeMediaProber()
+        scanner = PathlibFilesystemScanner()
         library_root = _infer_library_root(dest_path, media_type)
         store = SubtitleMetadataStore(library_root)
         repo = RuleSetRepository(library_root)
 
         # --- Pattern resolution ---
         pattern = self._resolve_pattern(
-            kb, store, source_path, confirmed_pattern_id, release_group
+            kb,
+            prober,
+            scanner,
+            store,
+            source_path,
+            confirmed_pattern_id,
+            release_group,
         )
         if pattern is None:
             return ManageSubtitlesResponse(
@@ -108,7 +118,7 @@ class ManageSubtitlesUseCase:
 
         # --- Identify ---
         media_id = _to_imdb_id(imdb_id)
-        identifier = SubtitleIdentifier(kb)
+        identifier = SubtitleIdentifier(kb, prober, scanner)
         metadata = identifier.identify(
             video_path=source_path,
             pattern=pattern,
@@ -153,7 +163,7 @@ class ManageSubtitlesUseCase:
             subtitle_prefs = memory.ltm.subtitle_preferences
         except Exception:
             pass
-        rules = repo.load(release_group, subtitle_prefs).resolve()
+        rules = repo.load(release_group, subtitle_prefs).resolve(kb.default_rules())
         matcher = SubtitleMatcher()
         matched, unresolved = matcher.match(metadata.external_tracks, rules)
 
@@ -228,6 +238,8 @@ class ManageSubtitlesUseCase:
     def _resolve_pattern(
         self,
         kb: SubtitleKnowledgeBase,
+        prober: FfprobeMediaProber,
+        scanner: PathlibFilesystemScanner,
         store: SubtitleMetadataStore,
         source_path: Path,
         confirmed_pattern_id: str | None,
@@ -250,7 +262,7 @@ class ManageSubtitlesUseCase:
 
         # 3. Auto-detect
         release_root = source_path.parent
-        detector = PatternDetector(kb)
+        detector = PatternDetector(kb, prober, scanner)
         result = detector.detect(release_root, source_path)
 
         if result["detected"] and result["confidence"] >= 0.6:

alfred/application/subtitles/placer.py

@@ -5,8 +5,8 @@ import os
 from dataclasses import dataclass
 from pathlib import Path
 
-from ..entities import SubtitleCandidate
-from ..value_objects import SubtitleType
+from alfred.domain.subtitles.entities import SubtitleCandidate
+from alfred.domain.subtitles.value_objects import SubtitleType
 
 logger = logging.getLogger(__name__)
 
@@ -78,8 +78,8 @@ class SubtitlePlacer:
                 skipped.append((track, "embedded — no file to place"))
                 continue
 
-            if not track.file_path or not track.file_path.exists():
-                skipped.append((track, "source file not found"))
+            if not track.file_path:
+                skipped.append((track, "source file not set"))
                 continue
 
             try:
@@ -90,11 +90,6 @@ class SubtitlePlacer:
 
             dest_path = dest_dir / dest_name
 
-            if dest_path.exists():
-                logger.debug(f"SubtitlePlacer: skip {dest_name} — already exists")
-                skipped.append((track, "destination already exists"))
-                continue
-
             try:
                 os.link(track.file_path, dest_path)
                 placed.append(
@@ -105,6 +100,11 @@ class SubtitlePlacer:
                     )
                 )
                 logger.info(f"SubtitlePlacer: placed {dest_name}")
+            except FileNotFoundError:
+                skipped.append((track, "source file not found"))
+            except FileExistsError:
+                logger.debug(f"SubtitlePlacer: skip {dest_name} — already exists")
+                skipped.append((track, "destination already exists"))
             except OSError as e:
                 logger.warning(f"SubtitlePlacer: failed to place {dest_name}: {e}")
                 skipped.append((track, str(e)))

alfred/domain/movies/entities.py

@@ -3,13 +3,13 @@
 from dataclasses import dataclass, field
 from datetime import datetime
 
-from ..shared.media import AudioTrack, SubtitleTrack, track_lang_matches
-from ..shared.value_objects import FilePath, FileSize, ImdbId, Language
+from ..shared.media import AudioTrack, MediaWithTracks, SubtitleTrack
+from ..shared.value_objects import FilePath, FileSize, ImdbId
 from .value_objects import MovieTitle, Quality, ReleaseYear
 
 
-@dataclass
-class Movie:
+@dataclass(eq=False)
+class Movie(MediaWithTracks):
     """
     Movie aggregate root for the movies domain.
 
@@ -20,6 +20,10 @@ class Movie:
     Track helpers follow the same "C+" contract as ``Episode``: pass a
     ``Language`` for cross-format matching, or a ``str`` for case-insensitive
     direct comparison.
+
+    Equality is identity-based: two ``Movie`` instances are equal iff they
+    share the same ``imdb_id``, regardless of file/track contents. This is
+    the DDD aggregate invariant — the aggregate is identified by its root id.
     """
 
     imdb_id: ImdbId
@@ -38,7 +42,7 @@ class Movie:
         # Ensure ImdbId is actually an ImdbId instance
         if not isinstance(self.imdb_id, ImdbId):
             if isinstance(self.imdb_id, str):
-                object.__setattr__(self, "imdb_id", ImdbId(self.imdb_id))
+                self.imdb_id = ImdbId(self.imdb_id)
             else:
                 raise ValueError(
                     f"imdb_id must be ImdbId or str, got {type(self.imdb_id)}"
@@ -47,55 +51,22 @@ class Movie:
         # Ensure MovieTitle is actually a MovieTitle instance
         if not isinstance(self.title, MovieTitle):
             if isinstance(self.title, str):
-                object.__setattr__(self, "title", MovieTitle(self.title))
+                self.title = MovieTitle(self.title)
             else:
                 raise ValueError(
                     f"title must be MovieTitle or str, got {type(self.title)}"
                 )
 
-    def has_file(self) -> bool:
-        """Check if the movie has an associated file."""
-        return self.file_path is not None and self.file_path.exists()
+    def __eq__(self, other: object) -> bool:
+        if not isinstance(other, Movie):
+            return NotImplemented
+        return self.imdb_id == other.imdb_id
 
-    def is_downloaded(self) -> bool:
-        """Check if the movie is downloaded (has a file)."""
-        return self.has_file()
+    def __hash__(self) -> int:
+        return hash(self.imdb_id)
 
-    # ── Audio helpers ──────────────────────────────────────────────────────
-
-    def has_audio_in(self, lang: str | Language) -> bool:
-        """True if at least one audio track is in the given language."""
-        return any(track_lang_matches(t.language, lang) for t in self.audio_tracks)
-
-    def audio_languages(self) -> list[str]:
-        """Unique audio languages across all tracks, in track order."""
-        seen: set[str] = set()
-        result: list[str] = []
-        for t in self.audio_tracks:
-            if t.language and t.language not in seen:
-                seen.add(t.language)
-                result.append(t.language)
-        return result
-
-    # ── Subtitle helpers ───────────────────────────────────────────────────
-
-    def has_subtitles_in(self, lang: str | Language) -> bool:
-        """True if at least one subtitle track is in the given language."""
-        return any(track_lang_matches(t.language, lang) for t in self.subtitle_tracks)
-
-    def has_forced_subs(self) -> bool:
-        """True if at least one subtitle track is flagged as forced."""
-        return any(t.is_forced for t in self.subtitle_tracks)
-
-    def subtitle_languages(self) -> list[str]:
-        """Unique subtitle languages across all tracks, in track order."""
-        seen: set[str] = set()
-        result: list[str] = []
-        for t in self.subtitle_tracks:
-            if t.language and t.language not in seen:
-                seen.add(t.language)
-                result.append(t.language)
-        return result
+    # Track helpers (has_audio_in / audio_languages / has_subtitles_in /
+    # has_forced_subs / subtitle_languages) come from MediaWithTracks.
 
     def get_folder_name(self) -> str:
         """

alfred/domain/release/services.py

@@ -4,7 +4,7 @@ from __future__ import annotations
 
 import re
 
-from .knowledge import load_separators
+from alfred.infrastructure.knowledge.release import load_separators
 from .value_objects import (
     _AUDIO,
     _CODECS,
@@ -16,7 +16,9 @@ from .value_objects import (
     _RESOLUTIONS,
     _SOURCES,
     _VIDEO_META,
+    MediaTypeToken,
     ParsedRelease,
+    ParsePath,
 )
 
 
@@ -39,12 +41,12 @@ def parse_release(name: str) -> ParsedRelease:
          and run token-level matchers (season/episode, tech, languages, audio,
          video, edition, title, year).
     """
-    parse_path = "direct"
+    parse_path = ParsePath.DIRECT.value
 
     # Always try to extract a bracket-enclosed site tag first.
     clean, site_tag = _strip_site_tag(name)
     if site_tag is not None:
-        parse_path = "sanitized"
+        parse_path = ParsePath.SANITIZED.value
 
     if not _is_well_formed(clean):
         return ParsedRelease(
@@ -60,9 +62,9 @@ def parse_release(name: str) -> ParsedRelease:
             codec=None,
             group="UNKNOWN",
             tech_string="",
-            media_type="unknown",
+            media_type=MediaTypeToken.UNKNOWN.value,
             site_tag=site_tag,
-            parse_path="ai",
+            parse_path=ParsePath.AI.value,
         )
 
     name = clean
@@ -137,19 +139,19 @@ def _infer_media_type(
     integrale_tokens = {t.upper() for t in _MEDIA_TYPE_TOKENS.get("integrale", [])}
 
     if upper_tokens & doc_tokens:
-        return "documentary"
+        return MediaTypeToken.DOCUMENTARY.value
     if upper_tokens & concert_tokens:
-        return "concert"
+        return MediaTypeToken.CONCERT.value
     if (
         edition in {"COMPLETE", "INTEGRALE", "COLLECTION"}
         or upper_tokens & integrale_tokens
     ) and season is None:
-        return "tv_complete"
+        return MediaTypeToken.TV_COMPLETE.value
     if season is not None:
-        return "tv_show"
+        return MediaTypeToken.TV_SHOW.value
     if any([quality, source, codec, year]):
-        return "movie"
-    return "unknown"
+        return MediaTypeToken.MOVIE.value
+    return MediaTypeToken.UNKNOWN.value
 
 
 def _is_well_formed(name: str) -> bool:

alfred/domain/release/value_objects.py

@@ -3,8 +3,10 @@
 from __future__ import annotations
 
 from dataclasses import dataclass, field
+from enum import Enum
 
-from .knowledge import (
+from ..shared.exceptions import ValidationError
+from alfred.infrastructure.knowledge.release import (
     load_audio,
     load_codecs,
     load_editions,
@@ -50,6 +52,38 @@ def _sanitize_for_fs(text: str) -> str:
     return text.translate(_WIN_FORBIDDEN_TABLE)
 
 
+class MediaTypeToken(str, Enum):
+    """
+    Canonical values for ``ParsedRelease.media_type``.
+
+    Inherits from ``str`` so existing string-based comparisons (``== "movie"``,
+    JSON serialization, TMDB DTO interop) keep working unchanged. The enum
+    serves both as documentation and as the set of valid values for
+    ``__post_init__`` validation.
+    """
+
+    MOVIE = "movie"
+    TV_SHOW = "tv_show"
+    TV_COMPLETE = "tv_complete"
+    DOCUMENTARY = "documentary"
+    CONCERT = "concert"
+    OTHER = "other"
+    UNKNOWN = "unknown"
+
+
+class ParsePath(str, Enum):
+    """How a ``ParsedRelease`` was produced. ``str``-backed for the same
+    reasons as :class:`MediaTypeToken`."""
+
+    DIRECT = "direct"
+    SANITIZED = "sanitized"
+    AI = "ai"
+
+
+_VALID_MEDIA_TYPES: frozenset[str] = frozenset(m.value for m in MediaTypeToken)
+_VALID_PARSE_PATHS: frozenset[str] = frozenset(p.value for p in ParsePath)
+
+
 def _strip_episode_from_normalized(normalized: str) -> str:
     """
     Remove all episode parts (Exx) from a normalized release name, keeping Sxx.
@@ -85,13 +119,11 @@ class ParsedRelease:
     codec: str | None  # x265, HEVC, …
     group: str  # release group, "UNKNOWN" if missing
     tech_string: str  # quality.source.codec joined with dots
-    media_type: str = (
-        "unknown"  # "movie" | "tv_show" | "tv_complete" | "other" | "unknown"
-    )
+    media_type: MediaTypeToken = MediaTypeToken.UNKNOWN
     site_tag: str | None = (
         None  # site watermark stripped from name, e.g. "TGx", "OxTorrent.vc"
     )
-    parse_path: str = "direct"  # "direct" | "sanitized" | "ai"
+    parse_path: ParsePath = ParsePath.DIRECT
     languages: list[str] = field(default_factory=list)  # ["MULTI", "VFF"], ["FRENCH"], …
     audio_codec: str | None = None  # "DTS-HD.MA", "DDP", "EAC3", …
     audio_channels: str | None = None  # "5.1", "7.1", "2.0", …
@@ -99,6 +131,51 @@ class ParsedRelease:
     hdr_format: str | None = None  # "DV", "HDR10", "DV.HDR10", …
     edition: str | None = None  # "UNRATED", "EXTENDED", "DIRECTORS.CUT", …
 
+    def __post_init__(self) -> None:
+        if not self.raw:
+            raise ValidationError("ParsedRelease.raw cannot be empty")
+        if not self.group:
+            raise ValidationError("ParsedRelease.group cannot be empty")
+        if self.year is not None and not (1888 <= self.year <= 2100):
+            raise ValidationError(
+                f"ParsedRelease.year out of range: {self.year}"
+            )
+        if self.season is not None and not (0 <= self.season <= 100):
+            raise ValidationError(
+                f"ParsedRelease.season out of range: {self.season}"
+            )
+        if self.episode is not None and not (0 <= self.episode <= 9999):
+            raise ValidationError(
+                f"ParsedRelease.episode out of range: {self.episode}"
+            )
+        if self.episode_end is not None:
+            if not (0 <= self.episode_end <= 9999):
+                raise ValidationError(
+                    f"ParsedRelease.episode_end out of range: {self.episode_end}"
+                )
+            if self.episode is not None and self.episode_end < self.episode:
+                raise ValidationError(
+                    f"ParsedRelease.episode_end ({self.episode_end}) < "
+                    f"episode ({self.episode})"
+                )
+        # Coerce raw strings into their enum form (tolerant constructor).
+        if not isinstance(self.media_type, MediaTypeToken):
+            try:
+                self.media_type = MediaTypeToken(self.media_type)
+            except ValueError:
+                raise ValidationError(
+                    f"ParsedRelease.media_type invalid: {self.media_type!r} "
+                    f"(expected one of {sorted(_VALID_MEDIA_TYPES)})"
+                ) from None
+        if not isinstance(self.parse_path, ParsePath):
+            try:
+                self.parse_path = ParsePath(self.parse_path)
+            except ValueError:
+                raise ValidationError(
+                    f"ParsedRelease.parse_path invalid: {self.parse_path!r} "
+                    f"(expected one of {sorted(_VALID_PARSE_PATHS)})"
+                ) from None
+
     @property
     def is_season_pack(self) -> bool:
         return self.season is not None and self.episode is None

alfred/domain/shared/knowledge/__init__.py

@@ -1,5 +0,0 @@
-"""Shared knowledge loaders (cross-domain)."""
-
-from .language_registry import LanguageRegistry
-
-__all__ = ["LanguageRegistry"]

alfred/domain/shared/media/__init__.py

@@ -8,11 +8,13 @@ from .audio import AudioTrack
 from .info import MediaInfo
 from .matching import track_lang_matches
 from .subtitle import SubtitleTrack
+from .tracks_mixin import MediaWithTracks
 from .video import VideoTrack
 
 __all__ = [
     "AudioTrack",
     "MediaInfo",
+    "MediaWithTracks",
     "SubtitleTrack",
     "VideoTrack",
     "track_lang_matches",

alfred/domain/shared/media/audio.py

@@ -5,7 +5,7 @@ from __future__ import annotations
 from dataclasses import dataclass
 
 
-@dataclass
+@dataclass(frozen=True)
 class AudioTrack:
     """A single audio track as reported by ffprobe."""
 

alfred/domain/shared/media/info.py

@@ -9,19 +9,21 @@ from .subtitle import SubtitleTrack
 from .video import VideoTrack
 
 
-@dataclass
+@dataclass(frozen=True)
 class MediaInfo:
     """
-    File-level media metadata extracted by ffprobe.
+    File-level media metadata extracted by ffprobe — immutable snapshot.
 
-    Symmetric design: every stream type is a list of typed track objects.
+    Symmetric design: every stream type is a tuple of typed track objects
+    (immutable on purpose — a MediaInfo is a frozen view of one ffprobe run,
+    not a mutable collection to append to).
     Backwards-compatible flat accessors (``resolution``, ``width``, …) read
     from the first video track when present.
     """
 
-    video_tracks: list[VideoTrack] = field(default_factory=list)
-    audio_tracks: list[AudioTrack] = field(default_factory=list)
-    subtitle_tracks: list[SubtitleTrack] = field(default_factory=list)
+    video_tracks: tuple[VideoTrack, ...] = field(default_factory=tuple)
+    audio_tracks: tuple[AudioTrack, ...] = field(default_factory=tuple)
+    subtitle_tracks: tuple[SubtitleTrack, ...] = field(default_factory=tuple)
 
     # File-level (from ffprobe ``format`` block, not from any single stream)
     duration_seconds: float | None = None

alfred/domain/shared/media/subtitle.py

@@ -14,7 +14,7 @@ from __future__ import annotations
 from dataclasses import dataclass
 
 
-@dataclass
+@dataclass(frozen=True)
 class SubtitleTrack:
     """A single embedded subtitle track as reported by ffprobe."""
 

alfred/domain/shared/media/tracks_mixin.py

@@ -0,0 +1,77 @@
+"""Mixin shared by entities that carry audio + subtitle tracks.
+
+Both ``Movie`` and ``Episode`` carry a ``list[AudioTrack]`` plus a
+``list[SubtitleTrack]`` and answer the same 5 queries about them (language
+presence, unique languages, forced flag). Keep that behavior in one place so a
+fix in one is a fix in both.
+
+The mixin is plain Python (no dataclass machinery) so it composes cleanly with
+``@dataclass`` entities — it only reads ``self.audio_tracks`` and
+``self.subtitle_tracks`` which the host class provides as fields.
+"""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from ..value_objects import Language
+from .matching import track_lang_matches
+
+if TYPE_CHECKING:
+    from .audio import AudioTrack
+    from .subtitle import SubtitleTrack
+
+
+class MediaWithTracks:
+    """
+    Mixin providing audio/subtitle helpers for entities with track collections.
+
+    Hosts must expose two attributes:
+
+    * ``audio_tracks: list[AudioTrack]``
+    * ``subtitle_tracks: list[SubtitleTrack]``
+
+    The helpers follow the "C+" matching contract: pass a :class:`Language`
+    for cross-format matching, or a ``str`` for case-insensitive comparison.
+    """
+
+    # These attributes are provided by the host entity (Movie, Episode, …).
+    # Declared here only for type-checkers and to make the contract explicit.
+    audio_tracks: list["AudioTrack"]
+    subtitle_tracks: list["SubtitleTrack"]
+
+    # ── Audio helpers ──────────────────────────────────────────────────────
+
+    def has_audio_in(self, lang: str | Language) -> bool:
+        """True if at least one audio track is in the given language."""
+        return any(track_lang_matches(t.language, lang) for t in self.audio_tracks)
+
+    def audio_languages(self) -> list[str]:
+        """Unique audio languages across all tracks, in track order."""
+        seen: set[str] = set()
+        result: list[str] = []
+        for t in self.audio_tracks:
+            if t.language and t.language not in seen:
+                seen.add(t.language)
+                result.append(t.language)
+        return result
+
+    # ── Subtitle helpers ───────────────────────────────────────────────────
+
+    def has_subtitles_in(self, lang: str | Language) -> bool:
+        """True if at least one subtitle track is in the given language."""
+        return any(track_lang_matches(t.language, lang) for t in self.subtitle_tracks)
+
+    def has_forced_subs(self) -> bool:
+        """True if at least one subtitle track is flagged as forced."""
+        return any(t.is_forced for t in self.subtitle_tracks)
+
+    def subtitle_languages(self) -> list[str]:
+        """Unique subtitle languages across all tracks, in track order."""
+        seen: set[str] = set()
+        result: list[str] = []
+        for t in self.subtitle_tracks:
+            if t.language and t.language not in seen:
+                seen.add(t.language)
+                result.append(t.language)
+        return result

alfred/domain/shared/media/video.py

@@ -5,7 +5,7 @@ from __future__ import annotations
 from dataclasses import dataclass
 
 
-@dataclass
+@dataclass(frozen=True)
 class VideoTrack:
     """A single video track as reported by ffprobe.
 

alfred/domain/shared/ports/__init__.py

@@ -0,0 +1,17 @@
+"""Ports — Protocol interfaces the domain depends on.
+
+Adapters live in ``alfred/infrastructure/`` and implement these protocols.
+Domain code never imports infrastructure; it accepts a port via constructor
+injection and calls it. Tests can pass in-memory fakes that satisfy the
+Protocol without going through real I/O.
+"""
+
+from .filesystem_scanner import FileEntry, FilesystemScanner
+from .media_prober import MediaProber, SubtitleStreamInfo
+
+__all__ = [
+    "FileEntry",
+    "FilesystemScanner",
+    "MediaProber",
+    "SubtitleStreamInfo",
+]

alfred/domain/shared/ports/filesystem_scanner.py

@@ -0,0 +1,59 @@
+"""FilesystemScanner port — abstracts filesystem inspection.
+
+The domain never calls ``Path.iterdir``, ``Path.is_file``, ``Path.stat`` or
+``open()`` directly. It asks the scanner for a ``FileEntry`` snapshot and
+reasons from there. One scan = one I/O round-trip; no callbacks back to disk.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from pathlib import Path
+from typing import Protocol
+
+
+@dataclass(frozen=True)
+class FileEntry:
+    """Frozen snapshot of one filesystem entry, taken at scan time.
+
+    The entry carries enough metadata for the domain to classify and order
+    files without re-querying the OS. ``size_kb`` is ``None`` for directories
+    and for files whose size could not be read.
+    """
+
+    path: Path
+    is_file: bool
+    is_dir: bool
+    size_kb: float | None
+
+    @property
+    def name(self) -> str:
+        return self.path.name
+
+    @property
+    def stem(self) -> str:
+        return self.path.stem
+
+    @property
+    def suffix(self) -> str:
+        return self.path.suffix
+
+
+class FilesystemScanner(Protocol):
+    """Read-only filesystem inspection."""
+
+    def scan_dir(self, path: Path) -> list[FileEntry]:
+        """Return sorted entries directly inside ``path``.
+
+        Returns an empty list when ``path`` is not a directory or is
+        unreadable. Adapters must not raise.
+        """
+        ...
+
+    def stat(self, path: Path) -> FileEntry | None:
+        """Stat a single path; ``None`` when it doesn't exist or is unreadable."""
+        ...
+
+    def read_text(self, path: Path, encoding: str = "utf-8") -> str | None:
+        """Read a text file in one go; ``None`` on any error."""
+        ...

alfred/domain/shared/ports/media_prober.py

@@ -0,0 +1,39 @@
+"""MediaProber port — abstracts media stream inspection (e.g. ffprobe).
+
+The adapter (typically wrapping ffprobe) maps low-level container metadata
+into the small set of stream attributes the domain reasons about. Replacing
+ffprobe with another tool only requires a new adapter — domain stays put.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from pathlib import Path
+from typing import Protocol
+
+
+@dataclass(frozen=True)
+class SubtitleStreamInfo:
+    """A single embedded subtitle stream, as seen by the prober.
+
+    ``language`` is the raw language tag emitted by the container (typically
+    ISO 639-2 like ``"fre"``, ``"eng"``); may be empty/None when the stream
+    has no language tag. The domain resolves it to a canonical ``Language``
+    via the knowledge base.
+    """
+
+    language: str | None
+    is_hearing_impaired: bool
+    is_forced: bool
+
+
+class MediaProber(Protocol):
+    """Inspect a media file's stream metadata."""
+
+    def list_subtitle_streams(self, video: Path) -> list[SubtitleStreamInfo]:
+        """Return all subtitle streams in ``video``.
+
+        Returns an empty list when the file is missing, unreadable, or has
+        no subtitle streams. Adapters must not raise.
+        """
+        ...

alfred/domain/shared/value_objects.py

@@ -67,18 +67,6 @@ class FilePath:
         # Use object.__setattr__ because dataclass is frozen
         object.__setattr__(self, "value", path_obj)
 
-    def exists(self) -> bool:
-        """Check if the path exists."""
-        return self.value.exists()
-
-    def is_file(self) -> bool:
-        """Check if the path is a file."""
-        return self.value.is_file()
-
-    def is_dir(self) -> bool:
-        """Check if the path is a directory."""
-        return self.value.is_dir()
-
     def __str__(self) -> str:
         return str(self.value)
 

alfred/domain/subtitles/__init__.py

@@ -3,7 +3,6 @@
 from .aggregates import SubtitleRuleSet
 from .entities import MediaSubtitleMetadata, SubtitleCandidate
 from .exceptions import SubtitleNotFound
-from .knowledge import KnowledgeLoader, SubtitleKnowledgeBase
 from .services import PatternDetector, SubtitleIdentifier, SubtitleMatcher
 from .value_objects import (
     RuleScope,
@@ -20,8 +19,6 @@ __all__ = [
     "SubtitleCandidate",
     "MediaSubtitleMetadata",
     "SubtitleRuleSet",
-    "SubtitleKnowledgeBase",
-    "KnowledgeLoader",
     "SubtitleIdentifier",
     "SubtitleMatcher",
     "PatternDetector",

alfred/domain/subtitles/aggregates.py

@@ -4,15 +4,9 @@ from dataclasses import dataclass, field
 from typing import Any
 
 from ..shared.value_objects import ImdbId
-from .knowledge.base import SubtitleKnowledgeBase
 from .value_objects import RuleScope, SubtitleMatchingRules
 
 
-def DEFAULT_RULES() -> SubtitleMatchingRules:
-    """Load default matching rules from subtitles.yaml (defaults section)."""
-    return SubtitleKnowledgeBase().default_rules()
-
-
 @dataclass
 class SubtitleRuleSet:
     """
@@ -36,12 +30,18 @@ class SubtitleRuleSet:
     _format_priority: list[str] | None = field(default=None, repr=False)
     _min_confidence: float | None = field(default=None, repr=False)
 
-    def resolve(self) -> SubtitleMatchingRules:
+    def resolve(self, default_rules: SubtitleMatchingRules) -> SubtitleMatchingRules:
         """
         Walk the parent chain and merge deltas into effective rules.
-        Falls back to DEFAULT_RULES at the top of the chain.
+
+        ``default_rules`` seeds the top of the chain — it is the caller's
+        responsibility to load these from the knowledge base (infrastructure).
+        Keeping the default rules as a parameter keeps the domain free of
+        any I/O dependency.
         """
-        base = self.parent.resolve() if self.parent else DEFAULT_RULES()
+        base = (
+            self.parent.resolve(default_rules) if self.parent else default_rules
+        )
         return SubtitleMatchingRules(
             preferred_languages=self._languages or base.preferred_languages,
             preferred_formats=self._formats or base.preferred_formats,

alfred/domain/subtitles/ports/__init__.py

@@ -0,0 +1,6 @@
+"""Domain ports for the subtitles domain — Protocol-based abstractions
+that decouple domain services from concrete infrastructure adapters."""
+
+from .knowledge import SubtitleKnowledge
+
+__all__ = ["SubtitleKnowledge"]

alfred/domain/subtitles/ports/knowledge.py

@@ -0,0 +1,38 @@
+"""SubtitleKnowledge port — the query surface domain services need from the
+subtitle knowledge base, expressed as a Protocol so the domain never imports
+the infrastructure adapter that backs it.
+
+The concrete implementation lives in
+``alfred/infrastructure/knowledge/subtitles/base.py`` (the YAML-backed
+``SubtitleKnowledgeBase``). Tests can supply any object that satisfies this
+structural contract.
+"""
+
+from __future__ import annotations
+
+from typing import Protocol
+
+from ..value_objects import SubtitleFormat, SubtitleLanguage, SubtitlePattern, SubtitleType
+
+
+class SubtitleKnowledge(Protocol):
+    """Read-only query surface for subtitle knowledge consumed by the domain.
+
+    Only the methods that domain services actually call belong here — anything
+    else (defaults loading, reload, pattern groups, raw dicts) stays on the
+    concrete class and is reserved for the application layer.
+    """
+
+    def known_extensions(self) -> set[str]: ...
+
+    def format_for_extension(self, ext: str) -> SubtitleFormat | None: ...
+
+    def language_for_token(self, token: str) -> SubtitleLanguage | None: ...
+
+    def is_known_lang_token(self, token: str) -> bool: ...
+
+    def type_for_token(self, token: str) -> SubtitleType | None: ...
+
+    def is_known_type_token(self, token: str) -> bool: ...
+
+    def patterns(self) -> dict[str, SubtitlePattern]: ...

alfred/domain/subtitles/scanner.py

@@ -1,207 +0,0 @@
-"""SubtitleScanner — inspects local subtitle files and filters them per user preferences.
-
-Given a video file path, the scanner:
-  1. Looks for subtitle files in the same directory as the video.
-  2. Optionally also inspects a Subs/ subfolder adjacent to the video.
-  3. Classifies each file (language, SDH, forced) from its filename, delegating
-     all token knowledge to SubtitleKnowledgeBase (which itself merges
-     LanguageRegistry + subtitle-specific tokens from subtitles.yaml).
-  4. Filters according to SubtitlePreferences (languages, min_size_kb, keep_sdh,
-     keep_forced).
-  5. Returns a list of SubtitleCandidate — one per file that passes the filter,
-     with the destination filename already computed.
-
-Filename classification heuristics
------------------------------------
-We parse the stem of each subtitle file looking for known patterns:
-
-  fre.srt             → lang=fre, sdh=False, forced=False
-  fre.sdh.srt         → lang=fre, sdh=True
-  fre.forced.srt      → lang=fre, forced=True
-  Breaking.Bad.S01E01.French.srt  → lang=fre (alias match via LanguageRegistry)
-  Breaking.Bad.S01E01.VOSTFR.srt  → lang=fre (subtitle-specific token)
-
-ISO 639-2/B codes are used throughout (matching the project-wide canonical form
-from iso_languages.yaml — what ffprobe emits).
-
-Output naming convention (matches SubtitlePreferences docstring):
-  {lang}.srt
-  {lang}.sdh.srt
-  {lang}.forced.srt
-"""
-
-import logging
-import re
-from dataclasses import dataclass
-from pathlib import Path
-
-from .knowledge.base import SubtitleKnowledgeBase
-from .value_objects import SubtitleType
-
-logger = logging.getLogger(__name__)
-
-_TOKEN_SPLIT = re.compile(r"[\.\s_\-]+")
-
-
-@dataclass
-class SubtitleCandidate:
-    """A subtitle file that passed the filter, ready to be placed."""
-
-    source_path: Path
-    language: str  # ISO 639-2/B code, e.g. "fre"
-    is_sdh: bool
-    is_forced: bool
-    extension: str  # e.g. ".srt"
-
-    @property
-    def destination_name(self) -> str:
-        """
-        Compute the destination filename per naming convention:
-            {lang}.srt
-            {lang}.sdh.srt
-            {lang}.forced.srt
-        """
-        ext = self.extension.lstrip(".")
-        parts = [self.language]
-        if self.is_sdh:
-            parts.append("sdh")
-        elif self.is_forced:
-            parts.append("forced")
-        return ".".join(parts) + "." + ext
-
-
-# Module-level KB instance — built lazily on first use to avoid loading YAML at import.
-_KB: SubtitleKnowledgeBase | None = None
-
-
-def _kb() -> SubtitleKnowledgeBase:
-    global _KB  # noqa: PLW0603 — intentional lazy module-level cache
-    if _KB is None:
-        _KB = SubtitleKnowledgeBase()
-    return _KB
-
-
-def _classify(path: Path) -> tuple[str | None, bool, bool]:
-    """
-    Parse a subtitle filename and return (language_code, is_sdh, is_forced).
-
-    ``language_code`` is the ISO 639-2/B canonical code (e.g. ``"fre"``).
-    Returns (None, False, False) if the language cannot be determined.
-    """
-    stem = path.stem.lower()
-    tokens = _TOKEN_SPLIT.split(stem)
-    kb = _kb()
-
-    language: str | None = None
-    is_sdh = False
-    is_forced = False
-
-    for token in tokens:
-        if not token:
-            continue
-        if language is None:
-            lang = kb.language_for_token(token)
-            if lang is not None:
-                language = lang.code
-                continue
-        stype = kb.type_for_token(token)
-        if stype is SubtitleType.SDH:
-            is_sdh = True
-        elif stype is SubtitleType.FORCED:
-            is_forced = True
-
-    return language, is_sdh, is_forced
-
-
-class SubtitleScanner:
-    """
-    Scans subtitle files next to a video and filters them per SubtitlePreferences.
-
-    Usage:
-        scanner = SubtitleScanner(prefs)
-        candidates = scanner.scan(video_path)
-        # Each candidate has .source_path and .destination_name
-    """
-
-    def __init__(
-        self, languages: list[str], min_size_kb: int, keep_sdh: bool, keep_forced: bool
-    ):
-        self.languages = [lang.lower() for lang in languages]
-        self.min_size_kb = min_size_kb
-        self.keep_sdh = keep_sdh
-        self.keep_forced = keep_forced
-        self._kb = _kb()
-        self._subtitle_extensions = {e.lower() for e in self._kb.known_extensions()}
-
-    def scan(self, video_path: Path) -> list[SubtitleCandidate]:
-        """
-        Return all subtitle candidates found next to the video that pass the filter.
-
-        Scans:
-          - Same directory as the video (flat siblings)
-          - Subs/ subfolder if present
-        """
-        candidates: list[SubtitleCandidate] = []
-        search_dirs = [video_path.parent]
-
-        subs_dir = video_path.parent / "Subs"
-        if subs_dir.is_dir():
-            search_dirs.append(subs_dir)
-            logger.debug(f"SubtitleScanner: found Subs/ folder at {subs_dir}")
-
-        for directory in search_dirs:
-            for path in sorted(directory.iterdir()):
-                if not path.is_file():
-                    continue
-                if path.suffix.lower() not in self._subtitle_extensions:
-                    continue
-
-                candidate = self._evaluate(path)
-                if candidate is not None:
-                    candidates.append(candidate)
-
-        logger.info(
-            f"SubtitleScanner: {len(candidates)} candidate(s) found for {video_path.name}"
-        )
-        return candidates
-
-    def _evaluate(self, path: Path) -> SubtitleCandidate | None:
-        """Apply all filters to a single subtitle file. Returns None if it should be dropped."""
-        # Size filter
-        size_kb = path.stat().st_size / 1024
-        if size_kb < self.min_size_kb:
-            logger.debug(
-                f"SubtitleScanner: skip {path.name} (too small: {size_kb:.1f} KB)"
-            )
-            return None
-
-        language, is_sdh, is_forced = _classify(path)
-
-        # Language filter
-        if language is None:
-            logger.debug(f"SubtitleScanner: skip {path.name} (language unknown)")
-            return None
-
-        if language not in self.languages:
-            logger.debug(
-                f"SubtitleScanner: skip {path.name} (language '{language}' not in prefs)"
-            )
-            return None
-
-        # SDH filter
-        if is_sdh and not self.keep_sdh:
-            logger.debug(f"SubtitleScanner: skip {path.name} (SDH not wanted)")
-            return None
-
-        # Forced filter
-        if is_forced and not self.keep_forced:
-            logger.debug(f"SubtitleScanner: skip {path.name} (forced not wanted)")
-            return None
-
-        return SubtitleCandidate(
-            source_path=path,
-            language=language,
-            is_sdh=is_sdh,
-            is_forced=is_forced,
-            extension=path.suffix.lower(),
-        )

alfred/domain/subtitles/services/__init__.py

@@ -1,13 +1,9 @@
 from .identifier import SubtitleIdentifier
 from .matcher import SubtitleMatcher
 from .pattern_detector import PatternDetector
-from .placer import PlacedTrack, PlaceResult, SubtitlePlacer
 
 __all__ = [
     "SubtitleIdentifier",
     "SubtitleMatcher",
     "PatternDetector",
-    "SubtitlePlacer",
-    "PlacedTrack",
-    "PlaceResult",
 ]

alfred/domain/subtitles/services/identifier.py

@@ -1,14 +1,13 @@
 """SubtitleIdentifier — finds and classifies all subtitle tracks for a video file."""
 
-import json
 import logging
 import re
-import subprocess
 from pathlib import Path
 
+from ...shared.ports import FilesystemScanner, MediaProber
+from ..ports import SubtitleKnowledge
 from ...shared.value_objects import ImdbId
 from ..entities import MediaSubtitleMetadata, SubtitleCandidate
-from ..knowledge.base import SubtitleKnowledgeBase
 from ..value_objects import ScanStrategy, SubtitlePattern, SubtitleType
 
 logger = logging.getLogger(__name__)
@@ -37,17 +36,14 @@ def _tokenize_suffix(stem: str, episode_stem: str) -> list[str]:
     return _tokenize(stem)
 
 
-def _count_entries(path: Path) -> int:
-    """Return the entry count of an SRT file by finding the last cue number."""
-    try:
-        with open(path, encoding="utf-8", errors="replace") as f:
-            lines = f.read().splitlines()
-        for line in reversed(lines):
-            if line.strip().isdigit():
-                return int(line.strip())
-        return 0
-    except Exception:
-        return 0
+def _count_entries(text: str | None) -> int | None:
+    """Return the entry count of an SRT body by finding the last cue number."""
+    if text is None:
+        return None
+    for line in reversed(text.splitlines()):
+        if line.strip().isdigit():
+            return int(line.strip())
+    return 0
 
 
 class SubtitleIdentifier:
@@ -60,8 +56,15 @@ class SubtitleIdentifier:
     the caller (use case) decides whether to ask the user for clarification.
     """
 
-    def __init__(self, kb: SubtitleKnowledgeBase):
+    def __init__(
+        self,
+        kb: SubtitleKnowledge,
+        prober: MediaProber,
+        scanner: FilesystemScanner,
+    ):
         self.kb = kb
+        self.prober = prober
+        self.scanner = scanner
 
     def identify(
         self,
@@ -88,52 +91,21 @@ class SubtitleIdentifier:
         return metadata
 
     # ------------------------------------------------------------------
-    # Embedded tracks — ffprobe
+    # Embedded tracks — via MediaProber
     # ------------------------------------------------------------------
 
     def _scan_embedded(self, video_path: Path) -> list[SubtitleCandidate]:
-        if not video_path.exists():
-            return []
-        try:
-            result = subprocess.run(
-                [
-                    "ffprobe",
-                    "-v",
-                    "quiet",
-                    "-print_format",
-                    "json",
-                    "-show_streams",
-                    "-select_streams",
-                    "s",
-                    str(video_path),
-                ],
-                capture_output=True,
-                text=True,
-                timeout=30,
-                check=False,
-            )
-            data = json.loads(result.stdout)
-        except (
-            subprocess.TimeoutExpired,
-            json.JSONDecodeError,
-            FileNotFoundError,
-        ) as e:
-            logger.debug(
-                f"SubtitleIdentifier: ffprobe failed for {video_path.name}: {e}"
-            )
-            return []
+        streams = self.prober.list_subtitle_streams(video_path)
 
         tracks = []
-        for stream in data.get("streams", []):
-            tags = stream.get("tags", {})
-            disposition = stream.get("disposition", {})
-            lang_code = tags.get("language", "")
+        for stream in streams:
+            lang = (
+                self.kb.language_for_token(stream.language) if stream.language else None
+            )
 
-            lang = self.kb.language_for_token(lang_code) if lang_code else None
-
-            if disposition.get("hearing_impaired"):
+            if stream.is_hearing_impaired:
                 stype = SubtitleType.SDH
-            elif disposition.get("forced"):
+            elif stream.is_forced:
                 stype = SubtitleType.FORCED
             else:
                 stype = SubtitleType.STANDARD
@@ -144,7 +116,7 @@ class SubtitleIdentifier:
                     format=None,
                     subtitle_type=stype,
                     is_embedded=True,
-                    raw_tokens=[lang_code] if lang_code else [],
+                    raw_tokens=[stream.language] if stream.language else [],
                 )
             )
 
@@ -176,57 +148,47 @@ class SubtitleIdentifier:
 
         return self._classify_files(candidates, pattern, episode_stem=episode_stem)
 
-    def _find_adjacent(self, video_path: Path) -> list[Path]:
+    def _find_adjacent(self, video_path: Path) -> list:
+        known = self.kb.known_extensions()
         return [
-            p
-            for p in sorted(video_path.parent.iterdir())
-            if p.is_file()
-            and p.suffix.lower() in self.kb.known_extensions()
-            and p.stem != video_path.stem
+            entry
+            for entry in self.scanner.scan_dir(video_path.parent)
+            if entry.is_file
+            and entry.suffix.lower() in known
+            and entry.stem != video_path.stem
         ]
 
-    def _find_flat(self, video_path: Path, root_folder: str) -> list[Path]:
-        subs_dir = video_path.parent / root_folder
-        if not subs_dir.is_dir():
-            # Also look at release root (one level up)
-            subs_dir = video_path.parent.parent / root_folder
-        if not subs_dir.is_dir():
-            return []
-        return [
-            p
-            for p in sorted(subs_dir.iterdir())
-            if p.is_file() and p.suffix.lower() in self.kb.known_extensions()
-        ]
+    def _find_flat(self, video_path: Path, root_folder: str) -> list:
+        known = self.kb.known_extensions()
+        # Adjacent first, then release root (one level up)
+        for subs_dir in (
+            video_path.parent / root_folder,
+            video_path.parent.parent / root_folder,
+        ):
+            entries = self.scanner.scan_dir(subs_dir)
+            if entries:
+                return [
+                    e for e in entries if e.is_file and e.suffix.lower() in known
+                ]
+        return []
 
     def _find_episode_subfolder(
         self, video_path: Path, root_folder: str
-    ) -> tuple[list[Path], str]:
-        """
-        Look for Subs/{episode_stem}/*.srt
-
-        Checks two locations:
-          1. Adjacent to the video: video_path.parent / root_folder / video_path.stem
-          2. Release root (one level up): video_path.parent.parent / root_folder / video_path.stem
-
-        Returns (files, episode_stem) so the classifier can strip the prefix.
-        """
+    ) -> tuple[list, str]:
+        """Look for Subs/{episode_stem}/*.srt — adjacent or one level up."""
         episode_stem = video_path.stem
-        candidates_dirs = [
+        known = self.kb.known_extensions()
+        for subs_dir in (
             video_path.parent / root_folder / episode_stem,
             video_path.parent.parent / root_folder / episode_stem,
-        ]
-        for subs_dir in candidates_dirs:
-            if subs_dir.is_dir():
-                files = [
-                    p
-                    for p in sorted(subs_dir.iterdir())
-                    if p.is_file() and p.suffix.lower() in self.kb.known_extensions()
-                ]
-                if files:
-                    logger.debug(
-                        f"SubtitleIdentifier: found {len(files)} file(s) in {subs_dir}"
-                    )
-                    return files, episode_stem
+        ):
+            entries = self.scanner.scan_dir(subs_dir)
+            files = [e for e in entries if e.is_file and e.suffix.lower() in known]
+            if files:
+                logger.debug(
+                    f"SubtitleIdentifier: found {len(files)} file(s) in {subs_dir}"
+                )
+                return files, episode_stem
         return [], episode_stem
 
     # ------------------------------------------------------------------
@@ -235,14 +197,13 @@ class SubtitleIdentifier:
 
     def _classify_files(
         self,
-        paths: list[Path],
+        entries: list,
         pattern: SubtitlePattern,
         episode_stem: str | None = None,
     ) -> list[SubtitleCandidate]:
-        tracks = []
-        for path in paths:
-            track = self._classify_single(path, episode_stem=episode_stem)
-            tracks.append(track)
+        tracks = [
+            self._classify_single(entry, episode_stem=episode_stem) for entry in entries
+        ]
 
         # Post-process: if multiple tracks share same language but type is ambiguous,
         # apply size_and_count disambiguation
@@ -252,13 +213,13 @@ class SubtitleIdentifier:
         return tracks
 
     def _classify_single(
-        self, path: Path, episode_stem: str | None = None
+        self, entry, episode_stem: str | None = None
     ) -> SubtitleCandidate:
-        fmt = self.kb.format_for_extension(path.suffix)
+        fmt = self.kb.format_for_extension(entry.suffix)
         tokens = (
-            _tokenize_suffix(path.stem, episode_stem)
+            _tokenize_suffix(entry.stem, episode_stem)
             if episode_stem
-            else _tokenize(path.stem)
+            else _tokenize(entry.stem)
         )
 
         language = None
@@ -284,19 +245,21 @@ class SubtitleIdentifier:
 
         if unknown_tokens:
             logger.debug(
-                f"SubtitleIdentifier: unknown tokens in '{path.name}': {unknown_tokens}"
+                f"SubtitleIdentifier: unknown tokens in '{entry.name}': {unknown_tokens}"
             )
 
-        size_kb = path.stat().st_size / 1024 if path.exists() else None
-        entry_count = _count_entries(path) if path.exists() else None
+        # Entry count: only meaningful for SRT files; read text on demand.
+        entry_count: int | None = None
+        if entry.suffix.lower() == ".srt":
+            entry_count = _count_entries(self.scanner.read_text(entry.path))
 
         return SubtitleCandidate(
             language=language,
             format=fmt,
             subtitle_type=subtitle_type,
             is_embedded=False,
-            file_path=path,
-            file_size_kb=size_kb,
+            file_path=entry.path,
+            file_size_kb=entry.size_kb,
             entry_count=entry_count,
             confidence=confidence,
             raw_tokens=tokens,

alfred/domain/subtitles/services/pattern_detector.py

@@ -1,11 +1,10 @@
 """PatternDetector — discovers the subtitle structure of a release folder."""
 
-import json
 import logging
-import subprocess
 from pathlib import Path
 
-from ..knowledge.base import SubtitleKnowledgeBase
+from ...shared.ports import FilesystemScanner, MediaProber
+from ..ports import SubtitleKnowledge
 from ..value_objects import ScanStrategy, SubtitlePattern
 
 logger = logging.getLogger(__name__)
@@ -20,8 +19,15 @@ class PatternDetector:
     a release follows. The result is proposed to the user for confirmation.
     """
 
-    def __init__(self, kb: SubtitleKnowledgeBase):
+    def __init__(
+        self,
+        kb: SubtitleKnowledge,
+        prober: MediaProber,
+        scanner: FilesystemScanner,
+    ):
         self.kb = kb
+        self.prober = prober
+        self.scanner = scanner
 
     def detect(self, release_root: Path, sample_video: Path) -> dict:
         """
@@ -45,29 +51,7 @@ class PatternDetector:
         }
 
     def _has_embedded_subtitles(self, video_path: Path) -> bool:
-        """Run ffprobe to check whether the video has embedded subtitle streams."""
-        try:
-            result = subprocess.run(
-                [
-                    "ffprobe",
-                    "-v",
-                    "quiet",
-                    "-print_format",
-                    "json",
-                    "-show_streams",
-                    "-select_streams",
-                    "s",
-                    str(video_path),
-                ],
-                capture_output=True,
-                text=True,
-                timeout=30,
-                check=False,
-            )
-            data = json.loads(result.stdout)
-            return len(data.get("streams", [])) > 0
-        except (subprocess.TimeoutExpired, json.JSONDecodeError, FileNotFoundError):
-            return False
+        return len(self.prober.list_subtitle_streams(video_path)) > 0
 
     def _inspect(self, release_root: Path, sample_video: Path) -> dict:
         """Gather structural facts about the release."""
@@ -84,61 +68,59 @@ class PatternDetector:
         }
 
         # Check for Subs/ folder — adjacent or at release root
-        for subs_candidate in [
+        for subs_candidate in (
             sample_video.parent / "Subs",
             release_root / "Subs",
-        ]:
-            if subs_candidate.is_dir():
-                findings["has_subs_folder"] = True
-                findings["subs_root"] = str(subs_candidate)
+        ):
+            children = self.scanner.scan_dir(subs_candidate)
+            if not children:
+                continue
 
-                # Is it flat or episode_subfolder?
-                children = list(subs_candidate.iterdir())
-                sub_files = [
-                    c
-                    for c in children
-                    if c.is_file() and c.suffix.lower() in known_exts
+            findings["has_subs_folder"] = True
+            findings["subs_root"] = str(subs_candidate)
+
+            # Is it flat or episode_subfolder?
+            sub_files = [
+                c for c in children if c.is_file and c.suffix.lower() in known_exts
+            ]
+            sub_dirs = [c for c in children if c.is_dir]
+
+            if sub_dirs and not sub_files:
+                findings["subs_strategy"] = "episode_subfolder"
+                # Count files in a sample subfolder
+                sample_files = [
+                    f
+                    for f in self.scanner.scan_dir(sub_dirs[0].path)
+                    if f.is_file and f.suffix.lower() in known_exts
                 ]
-                sub_dirs = [c for c in children if c.is_dir()]
-
-                if sub_dirs and not sub_files:
-                    findings["subs_strategy"] = "episode_subfolder"
-                    # Count files in a sample subfolder
-                    sample_sub = sub_dirs[0]
-                    sample_files = [
-                        f
-                        for f in sample_sub.iterdir()
-                        if f.is_file() and f.suffix.lower() in known_exts
-                    ]
-                    findings["files_per_episode"] = len(sample_files)
-                    # Check naming conventions
-                    for f in sample_files:
-                        stem = f.stem
-                        parts = stem.split("_")
-                        if parts[0].isdigit():
-                            findings["has_numeric_prefix"] = True
-                        if any(
-                            self.kb.is_known_lang_token(t.lower())
-                            for t in stem.replace("_", ".").split(".")
-                        ):
-                            findings["has_lang_tokens"] = True
-                else:
-                    findings["subs_strategy"] = "flat"
-                    findings["files_per_episode"] = len(sub_files)
-                    for f in sub_files:
-                        if any(
-                            self.kb.is_known_lang_token(t.lower())
-                            for t in f.stem.replace("_", ".").split(".")
-                        ):
-                            findings["has_lang_tokens"] = True
-                break
+                findings["files_per_episode"] = len(sample_files)
+                # Check naming conventions
+                for f in sample_files:
+                    parts = f.stem.split("_")
+                    if parts[0].isdigit():
+                        findings["has_numeric_prefix"] = True
+                    if any(
+                        self.kb.is_known_lang_token(t.lower())
+                        for t in f.stem.replace("_", ".").split(".")
+                    ):
+                        findings["has_lang_tokens"] = True
+            else:
+                findings["subs_strategy"] = "flat"
+                findings["files_per_episode"] = len(sub_files)
+                for f in sub_files:
+                    if any(
+                        self.kb.is_known_lang_token(t.lower())
+                        for t in f.stem.replace("_", ".").split(".")
+                    ):
+                        findings["has_lang_tokens"] = True
+            break
 
         # Check adjacent subs (next to the video)
         if not findings["has_subs_folder"]:
             adjacent = [
-                p
-                for p in sample_video.parent.iterdir()
-                if p.is_file() and p.suffix.lower() in known_exts
+                e
+                for e in self.scanner.scan_dir(sample_video.parent)
+                if e.is_file and e.suffix.lower() in known_exts
             ]
             if adjacent:
                 findings["adjacent_subs"] = True
@@ -221,6 +203,6 @@ class PatternDetector:
             parts.append("no external subtitle files found")
 
         if findings.get("has_embedded"):
-            parts.append("embedded tracks detected (ffprobe)")
+            parts.append("embedded tracks detected")
 
         return " — ".join(parts) if parts else "nothing found"

alfred/domain/tv_shows/entities.py

@@ -28,12 +28,11 @@ from __future__ import annotations
 import re
 from dataclasses import dataclass, field
 
-from ..shared.media import AudioTrack, SubtitleTrack, track_lang_matches
+from ..shared.media import AudioTrack, MediaWithTracks, SubtitleTrack
 from ..shared.value_objects import (
     FilePath,
     FileSize,
     ImdbId,
-    Language,
     to_dot_folder_name,
 )
 from .value_objects import (
@@ -48,8 +47,8 @@ from .value_objects import (
 # ════════════════════════════════════════════════════════════════════════════
 
 
-@dataclass
-class Episode:
+@dataclass(eq=False)
+class Episode(MediaWithTracks):
     """
     A single episode of a TV show — leaf of the TVShow aggregate.
 
@@ -57,6 +56,11 @@ class Episode:
     (audio + subtitle). Track lists are populated by the ffprobe + subtitle
     scan pipeline; they may be empty when the episode is known but not yet
     scanned, or when no file is downloaded yet.
+
+    Equality is identity-based within the aggregate: two ``Episode`` instances
+    are equal iff they share the same ``(season_number, episode_number)``,
+    regardless of title/file/track contents. The root TVShow guarantees
+    cross-show uniqueness.
     """
 
     season_number: SeasonNumber
@@ -76,51 +80,19 @@ class Episode:
             if isinstance(self.episode_number, int):
                 self.episode_number = EpisodeNumber(self.episode_number)
 
-    # ── File presence ──────────────────────────────────────────────────────
+    def __eq__(self, other: object) -> bool:
+        if not isinstance(other, Episode):
+            return NotImplemented
+        return (
+            self.season_number == other.season_number
+            and self.episode_number == other.episode_number
+        )
 
-    def has_file(self) -> bool:
-        """True if a file path is set and the file actually exists on disk."""
-        return self.file_path is not None and self.file_path.exists()
+    def __hash__(self) -> int:
+        return hash((self.season_number, self.episode_number))
 
-    def is_downloaded(self) -> bool:
-        """Alias of ``has_file()`` — reads better in collection-status contexts."""
-        return self.has_file()
-
-    # ── Audio helpers ──────────────────────────────────────────────────────
-
-    def has_audio_in(self, lang: str | Language) -> bool:
-        """True if at least one audio track is in the given language."""
-        return any(track_lang_matches(t.language, lang) for t in self.audio_tracks)
-
-    def audio_languages(self) -> list[str]:
-        """Unique audio languages across all tracks, in track order."""
-        seen: set[str] = set()
-        result: list[str] = []
-        for t in self.audio_tracks:
-            if t.language and t.language not in seen:
-                seen.add(t.language)
-                result.append(t.language)
-        return result
-
-    # ── Subtitle helpers ───────────────────────────────────────────────────
-
-    def has_subtitles_in(self, lang: str | Language) -> bool:
-        """True if at least one subtitle track is in the given language."""
-        return any(track_lang_matches(t.language, lang) for t in self.subtitle_tracks)
-
-    def has_forced_subs(self) -> bool:
-        """True if at least one subtitle track is flagged as forced."""
-        return any(t.is_forced for t in self.subtitle_tracks)
-
-    def subtitle_languages(self) -> list[str]:
-        """Unique subtitle languages across all tracks, in track order."""
-        seen: set[str] = set()
-        result: list[str] = []
-        for t in self.subtitle_tracks:
-            if t.language and t.language not in seen:
-                seen.add(t.language)
-                result.append(t.language)
-        return result
+    # Track helpers (has_audio_in / audio_languages / has_subtitles_in /
+    # has_forced_subs / subtitle_languages) come from MediaWithTracks.
 
     # ── Naming ─────────────────────────────────────────────────────────────
 

alfred/infrastructure/filesystem/ffprobe.py

@@ -57,27 +57,31 @@ def _parse(data: dict) -> MediaInfo:
     streams = data.get("streams", [])
     fmt = data.get("format", {})
 
-    info = MediaInfo()
-
     # File-level duration/bitrate (ffprobe ``format`` block — independent of streams)
+    duration_seconds: float | None = None
+    bitrate_kbps: int | None = None
     if "duration" in fmt:
         try:
-            info.duration_seconds = float(fmt["duration"])
+            duration_seconds = float(fmt["duration"])
         except ValueError:
             pass
     if "bit_rate" in fmt:
         try:
-            info.bitrate_kbps = int(fmt["bit_rate"]) // 1000
+            bitrate_kbps = int(fmt["bit_rate"]) // 1000
         except ValueError:
             pass
 
+    video_tracks: list[VideoTrack] = []
+    audio_tracks: list[AudioTrack] = []
+    subtitle_tracks: list[SubtitleTrack] = []
+
     for stream in streams:
         codec_type = stream.get("codec_type")
 
         if codec_type == "video":
-            info.video_tracks.append(
+            video_tracks.append(
                 VideoTrack(
-                    index=stream.get("index", len(info.video_tracks)),
+                    index=stream.get("index", len(video_tracks)),
                     codec=stream.get("codec_name"),
                     width=stream.get("width"),
                     height=stream.get("height"),
@@ -86,9 +90,9 @@ def _parse(data: dict) -> MediaInfo:
             )
 
         elif codec_type == "audio":
-            info.audio_tracks.append(
+            audio_tracks.append(
                 AudioTrack(
-                    index=stream.get("index", len(info.audio_tracks)),
+                    index=stream.get("index", len(audio_tracks)),
                     codec=stream.get("codec_name"),
                     channels=stream.get("channels"),
                     channel_layout=stream.get("channel_layout"),
@@ -98,9 +102,9 @@ def _parse(data: dict) -> MediaInfo:
             )
 
         elif codec_type == "subtitle":
-            info.subtitle_tracks.append(
+            subtitle_tracks.append(
                 SubtitleTrack(
-                    index=stream.get("index", len(info.subtitle_tracks)),
+                    index=stream.get("index", len(subtitle_tracks)),
                     codec=stream.get("codec_name"),
                     language=stream.get("tags", {}).get("language"),
                     is_default=stream.get("disposition", {}).get("default", 0) == 1,
@@ -108,4 +112,10 @@ def _parse(data: dict) -> MediaInfo:
                 )
             )
 
-    return info
+    return MediaInfo(
+        video_tracks=tuple(video_tracks),
+        audio_tracks=tuple(audio_tracks),
+        subtitle_tracks=tuple(subtitle_tracks),
+        duration_seconds=duration_seconds,
+        bitrate_kbps=bitrate_kbps,
+    )

alfred/infrastructure/filesystem/scanner.py

@@ -0,0 +1,66 @@
+"""PathlibFilesystemScanner — FilesystemScanner adapter backed by pathlib."""
+
+from __future__ import annotations
+
+import logging
+from pathlib import Path
+
+from alfred.domain.shared.ports import FileEntry
+
+logger = logging.getLogger(__name__)
+
+
+class PathlibFilesystemScanner:
+    """Read-only filesystem scanner using ``pathlib``.
+
+    Implements :class:`alfred.domain.shared.ports.FilesystemScanner`
+    structurally. Never raises — failures are logged and surfaced as
+    empty results.
+    """
+
+    def scan_dir(self, path: Path) -> list[FileEntry]:
+        try:
+            if not path.is_dir():
+                return []
+            children = sorted(path.iterdir())
+        except OSError as e:
+            logger.debug(f"PathlibFilesystemScanner: scan_dir failed for {path}: {e}")
+            return []
+
+        entries: list[FileEntry] = []
+        for child in children:
+            entry = self._make_entry(child)
+            if entry is not None:
+                entries.append(entry)
+        return entries
+
+    def stat(self, path: Path) -> FileEntry | None:
+        return self._make_entry(path)
+
+    def read_text(self, path: Path, encoding: str = "utf-8") -> str | None:
+        try:
+            with open(path, encoding=encoding, errors="replace") as f:
+                return f.read()
+        except OSError as e:
+            logger.debug(f"PathlibFilesystemScanner: read_text failed for {path}: {e}")
+            return None
+
+    # ------------------------------------------------------------------
+
+    def _make_entry(self, path: Path) -> FileEntry | None:
+        try:
+            is_file = path.is_file()
+            is_dir = path.is_dir()
+        except OSError:
+            return None
+        if not (is_file or is_dir):
+            return None
+
+        size_kb: float | None = None
+        if is_file:
+            try:
+                size_kb = path.stat().st_size / 1024
+            except OSError:
+                size_kb = None
+
+        return FileEntry(path=path, is_file=is_file, is_dir=is_dir, size_kb=size_kb)

alfred/infrastructure/knowledge/__init__.py

@@ -0,0 +1,6 @@
+"""Knowledge loaders — YAML I/O kept out of the domain layer.
+
+Each submodule reads its YAML files from ``alfred/knowledge/`` (builtin,
+versioned) and ``data/knowledge/`` (learned, gitignored), and exposes plain
+Python values (sets, dicts, classes) for domain code to consume.
+"""

alfred/infrastructure/knowledge/language_registry.py

@@ -13,7 +13,7 @@ import yaml
 
 import alfred as _alfred_pkg
 
-from ..value_objects import Language
+from alfred.domain.shared.value_objects import Language
 
 logger = logging.getLogger(__name__)
 

alfred/infrastructure/knowledge/subtitles/base.py

@@ -2,8 +2,8 @@
 
 import logging
 
-from ...shared.knowledge.language_registry import LanguageRegistry
-from ..value_objects import (
+from alfred.infrastructure.knowledge.language_registry import LanguageRegistry
+from alfred.domain.subtitles.value_objects import (
     ScanStrategy,
     SubtitleFormat,
     SubtitleLanguage,

alfred/infrastructure/probe/__init__.py

@@ -0,0 +1,5 @@
+"""Media probing adapters — concrete implementations of MediaProber."""
+
+from .ffprobe_prober import FfprobeMediaProber
+
+__all__ = ["FfprobeMediaProber"]

alfred/infrastructure/probe/ffprobe_prober.py

@@ -0,0 +1,65 @@
+"""FfprobeMediaProber — MediaProber adapter backed by the ffprobe CLI."""
+
+from __future__ import annotations
+
+import json
+import logging
+import subprocess
+from pathlib import Path
+
+from alfred.domain.shared.ports import SubtitleStreamInfo
+
+logger = logging.getLogger(__name__)
+
+_FFPROBE_TIMEOUT_SECONDS = 30
+
+
+class FfprobeMediaProber:
+    """Inspect media files by shelling out to ``ffprobe``.
+
+    Implements :class:`alfred.domain.shared.ports.MediaProber` structurally.
+    Never raises — failures are logged and surfaced as empty results.
+    """
+
+    def list_subtitle_streams(self, video: Path) -> list[SubtitleStreamInfo]:
+        if not video.exists():
+            return []
+        try:
+            result = subprocess.run(
+                [
+                    "ffprobe",
+                    "-v",
+                    "quiet",
+                    "-print_format",
+                    "json",
+                    "-show_streams",
+                    "-select_streams",
+                    "s",
+                    str(video),
+                ],
+                capture_output=True,
+                text=True,
+                timeout=_FFPROBE_TIMEOUT_SECONDS,
+                check=False,
+            )
+            data = json.loads(result.stdout)
+        except (
+            subprocess.TimeoutExpired,
+            json.JSONDecodeError,
+            FileNotFoundError,
+        ) as e:
+            logger.debug(f"FfprobeMediaProber: ffprobe failed for {video.name}: {e}")
+            return []
+
+        streams: list[SubtitleStreamInfo] = []
+        for stream in data.get("streams", []):
+            tags = stream.get("tags", {}) or {}
+            disposition = stream.get("disposition", {}) or {}
+            streams.append(
+                SubtitleStreamInfo(
+                    language=tags.get("language") or None,
+                    is_hearing_impaired=bool(disposition.get("hearing_impaired")),
+                    is_forced=bool(disposition.get("forced")),
+                )
+            )
+        return streams

alfred/infrastructure/subtitle/metadata_store.py

@@ -14,7 +14,7 @@ from pathlib import Path
 from typing import Any
 
 from alfred.domain.subtitles.entities import SubtitleCandidate
-from alfred.domain.subtitles.services.placer import PlacedTrack
+from alfred.application.subtitles.placer import PlacedTrack
 from alfred.infrastructure.metadata.store import MetadataStore
 
 logger = logging.getLogger(__name__)

alfred/infrastructure/subtitle/rule_repository.py

@@ -54,7 +54,7 @@ class RuleSetRepository:
         Build and return the resolved RuleSet chain.
 
         If subtitle_preferences is provided, it seeds the global base rule set
-        from LTM (overriding the hardcoded DEFAULT_RULES).
+        from LTM (overriding the knowledge-base defaults at resolve time).
         Returns global default if no overrides exist.
         """
         base = SubtitleRuleSet.global_default()

tests/application/test_manage_subtitles.py

@@ -41,7 +41,7 @@ from alfred.application.filesystem.manage_subtitles import (
     _to_unresolved_dto,
 )
 from alfred.domain.subtitles.entities import MediaSubtitleMetadata, SubtitleCandidate
-from alfred.domain.subtitles.services.placer import PlacedTrack, PlaceResult
+from alfred.application.subtitles.placer import PlacedTrack, PlaceResult
 from alfred.domain.subtitles.value_objects import (
     ScanStrategy,
     SubtitleFormat,

tests/application/test_subtitle_placer.py

@@ -1,4 +1,4 @@
-"""Tests for ``alfred.domain.subtitles.services.placer.SubtitlePlacer``.
+"""Tests for ``alfred.application.subtitles.placer.SubtitlePlacer``.
 
 The placer hard-links subtitle files next to a destination video, naming
 them ``{video_stem}.{lang}[.sdh|.forced].{ext}``.
@@ -22,7 +22,7 @@ from unittest.mock import patch
 import pytest
 
 from alfred.domain.subtitles.entities import SubtitleCandidate
-from alfred.domain.subtitles.services.placer import (
+from alfred.application.subtitles.placer import (
     PlacedTrack,
     PlaceResult,
     SubtitlePlacer,
@@ -198,7 +198,7 @@ class TestOSError:
         video.write_bytes(b"")
         track = _track(src)
         with patch(
-            "alfred.domain.subtitles.services.placer.os.link",
+            "alfred.application.subtitles.placer.os.link",
             side_effect=OSError("cross-device link"),
         ):
             result = placer.place([track], video)

tests/domain/test_shared_value_objects.py

@@ -72,23 +72,6 @@ class TestFilePath:
         with pytest.raises(ValidationError):
             FilePath(123)  # type: ignore
 
-    def test_exists_true(self, tmp_path):
-        p = FilePath(tmp_path)
-        assert p.exists()
-
-    def test_exists_false(self, tmp_path):
-        p = FilePath(tmp_path / "nonexistent")
-        assert not p.exists()
-
-    def test_is_file(self, tmp_path):
-        f = tmp_path / "file.txt"
-        f.write_text("x")
-        assert FilePath(f).is_file()
-        assert not FilePath(tmp_path).is_file()
-
-    def test_is_dir(self, tmp_path):
-        assert FilePath(tmp_path).is_dir()
-
     def test_str(self, tmp_path):
         p = FilePath(tmp_path)
         assert str(p) == str(tmp_path)

tests/domain/test_subtitle_identifier.py

@@ -22,8 +22,8 @@ from unittest.mock import patch
 
 import pytest
 
+from alfred.domain.shared.ports import FileEntry
 from alfred.domain.subtitles.entities import SubtitleCandidate
-from alfred.domain.subtitles.knowledge.base import SubtitleKnowledgeBase
 from alfred.domain.subtitles.services.identifier import (
     SubtitleIdentifier,
     _count_entries,
@@ -37,6 +37,19 @@ from alfred.domain.subtitles.value_objects import (
     SubtitleType,
     TypeDetectionMethod,
 )
+from alfred.infrastructure.filesystem.scanner import PathlibFilesystemScanner
+from alfred.infrastructure.knowledge.subtitles.base import SubtitleKnowledgeBase
+from alfred.infrastructure.probe.ffprobe_prober import FfprobeMediaProber
+
+
+def _file_entry(path) -> FileEntry:
+    """Helper: build a FileEntry from a real tmp_path Path."""
+    return FileEntry(
+        path=path,
+        is_file=path.is_file(),
+        is_dir=path.is_dir(),
+        size_kb=(path.stat().st_size / 1024) if path.is_file() else None,
+    )
 
 
 @pytest.fixture(scope="module")
@@ -46,7 +59,7 @@ def kb():
 
 @pytest.fixture
 def identifier(kb):
-    return SubtitleIdentifier(kb)
+    return SubtitleIdentifier(kb, FfprobeMediaProber(), PathlibFilesystemScanner())
 
 
 def _pattern(
@@ -103,23 +116,19 @@ class TestTokenize:
 
 
 class TestCountEntries:
-    def test_last_cue_number(self, tmp_path):
-        srt = tmp_path / "x.srt"
-        srt.write_text(
+    def test_last_cue_number(self):
+        text = (
             "1\n00:00:01,000 --> 00:00:02,000\nHello\n\n"
             "2\n00:00:03,000 --> 00:00:04,000\nWorld\n\n"
-            "42\n00:00:05,000 --> 00:00:06,000\nLast\n",
-            encoding="utf-8",
+            "42\n00:00:05,000 --> 00:00:06,000\nLast\n"
         )
-        assert _count_entries(srt) == 42
+        assert _count_entries(text) == 42
 
-    def test_missing_file_returns_zero(self, tmp_path):
-        assert _count_entries(tmp_path / "nope.srt") == 0
+    def test_missing_file_returns_none(self):
+        assert _count_entries(None) is None
 
-    def test_empty_file_returns_zero(self, tmp_path):
-        f = tmp_path / "x.srt"
-        f.write_text("")
-        assert _count_entries(f) == 0
+    def test_empty_file_returns_zero(self):
+        assert _count_entries("") == 0
 
 
 # --------------------------------------------------------------------------- #
@@ -135,7 +144,7 @@ class TestEmbedded:
         video = tmp_path / "v.mkv"
         video.write_bytes(b"")
         with patch(
-            "alfred.domain.subtitles.services.identifier.subprocess.run",
+            "alfred.infrastructure.probe.ffprobe_prober.subprocess.run",
             side_effect=FileNotFoundError("no ffprobe"),
         ):
             assert identifier._scan_embedded(video) == []
@@ -156,7 +165,7 @@ class TestEmbedded:
             stdout = fake_output
 
         with patch(
-            "alfred.domain.subtitles.services.identifier.subprocess.run",
+            "alfred.infrastructure.probe.ffprobe_prober.subprocess.run",
             return_value=FakeResult(),
         ):
             tracks = identifier._scan_embedded(video)
@@ -256,7 +265,7 @@ class TestClassify:
     def test_classifies_language_and_format(self, identifier, tmp_path):
         f = tmp_path / "Show.S01E01.English.srt"
         f.write_text("1\n00:00:01,000 --> 00:00:02,000\nHi\n")
-        track = identifier._classify_single(f)
+        track = identifier._classify_single(_file_entry(f))
         assert track.language.code == "eng"
         assert track.format.id == "srt"
         assert track.confidence > 0
@@ -265,13 +274,13 @@ class TestClassify:
     def test_classifies_type_token(self, identifier, tmp_path):
         f = tmp_path / "Show.S01E01.English.sdh.srt"
         f.write_text("")
-        track = identifier._classify_single(f)
+        track = identifier._classify_single(_file_entry(f))
         assert track.subtitle_type == SubtitleType.SDH
 
     def test_unknown_tokens_lower_confidence(self, identifier, tmp_path):
         f = tmp_path / "Show.S01E01.gibberish.srt"
         f.write_text("")
-        track = identifier._classify_single(f)
+        track = identifier._classify_single(_file_entry(f))
         # No lang/type recognized → confidence is 0 or very low.
         assert track.language is None
         assert track.confidence < 0.5
@@ -279,7 +288,9 @@ class TestClassify:
     def test_episode_stem_prefix_stripped(self, identifier, tmp_path):
         f = tmp_path / "Show.S01E01.English.srt"
         f.write_text("")
-        track = identifier._classify_single(f, episode_stem="Show.S01E01")
+        track = identifier._classify_single(
+            _file_entry(f), episode_stem="Show.S01E01"
+        )
         # Only "english" remains as meaningful token → confidence == 1.0
         assert track.language.code == "eng"
         assert track.confidence == 1.0

tests/domain/test_subtitle_knowledge.py

@@ -1,4 +1,4 @@
-"""Tests for ``alfred.domain.subtitles.knowledge`` (loader + base).
+"""Tests for ``alfred.infrastructure.knowledge.subtitles`` (loader + base).
 
 Covers:
 
@@ -19,9 +19,9 @@ from pathlib import Path
 
 import pytest
 
-from alfred.domain.subtitles.knowledge import loader as loader_mod
-from alfred.domain.subtitles.knowledge.base import SubtitleKnowledgeBase
-from alfred.domain.subtitles.knowledge.loader import KnowledgeLoader, _merge
+from alfred.infrastructure.knowledge.subtitles import loader as loader_mod
+from alfred.infrastructure.knowledge.subtitles.base import SubtitleKnowledgeBase
+from alfred.infrastructure.knowledge.subtitles.loader import KnowledgeLoader, _merge
 from alfred.domain.subtitles.value_objects import (
     ScanStrategy,
     SubtitleType,

tests/domain/test_subtitle_pattern_detector.py

@@ -25,8 +25,10 @@ from unittest.mock import patch
 
 import pytest
 
-from alfred.domain.subtitles.knowledge.base import SubtitleKnowledgeBase
 from alfred.domain.subtitles.services.pattern_detector import PatternDetector
+from alfred.infrastructure.filesystem.scanner import PathlibFilesystemScanner
+from alfred.infrastructure.knowledge.subtitles.base import SubtitleKnowledgeBase
+from alfred.infrastructure.probe.ffprobe_prober import FfprobeMediaProber
 
 
 @pytest.fixture(scope="module")
@@ -36,7 +38,7 @@ def kb():
 
 @pytest.fixture
 def detector(kb):
-    return PatternDetector(kb)
+    return PatternDetector(kb, FfprobeMediaProber(), PathlibFilesystemScanner())
 
 
 def _make_video(folder: Path, name: str = "Show.S01E01.mkv") -> Path:

tests/domain/test_subtitle_scanner.py

@@ -1,232 +0,0 @@
-"""Tests for SubtitleScanner and _classify helper."""
-
-from pathlib import Path
-
-from alfred.domain.subtitles.scanner import (
-    SubtitleCandidate,
-    SubtitleScanner,
-    _classify,
-)
-
-# ---------------------------------------------------------------------------
-# _classify — unit tests for the filename parser
-# ---------------------------------------------------------------------------
-
-
-class TestClassify:
-    def test_iso_lang_code_639_1_alias(self, tmp_path):
-        # ``fr`` is an alias of the canonical ISO 639-2/B code ``fre``.
-        p = tmp_path / "fr.srt"
-        p.write_text("")
-        lang, is_sdh, is_forced = _classify(p)
-        assert lang == "fre"
-        assert not is_sdh
-        assert not is_forced
-
-    def test_english_keyword(self, tmp_path):
-        p = tmp_path / "english.srt"
-        p.write_text("")
-        lang, _, _ = _classify(p)
-        assert lang == "eng"
-
-    def test_french_keyword(self, tmp_path):
-        p = tmp_path / "Show.S01E01.French.srt"
-        p.write_text("")
-        lang, _, _ = _classify(p)
-        assert lang == "fre"
-
-    def test_vostfr_is_french(self, tmp_path):
-        p = tmp_path / "Show.S01E01.VOSTFR.srt"
-        p.write_text("")
-        lang, _, _ = _classify(p)
-        assert lang == "fre"
-
-    def test_sdh_token(self, tmp_path):
-        p = tmp_path / "fre.sdh.srt"
-        p.write_text("")
-        lang, is_sdh, _ = _classify(p)
-        assert lang == "fre"
-        assert is_sdh
-
-    def test_hi_no_longer_marks_sdh(self, tmp_path):
-        # ``hi`` is the ISO 639-1 alias for Hindi; it must not mark a file as
-        # SDH any more (regression of the previous collision between SDH and
-        # Hindi tokens). Use ``sdh`` / ``cc`` / ``hearing`` to flag SDH instead.
-        p = tmp_path / "en.hi.srt"
-        p.write_text("")
-        lang, is_sdh, _ = _classify(p)
-        assert lang == "eng"
-        assert not is_sdh
-
-    def test_forced_token(self, tmp_path):
-        p = tmp_path / "fre.forced.srt"
-        p.write_text("")
-        _, _, is_forced = _classify(p)
-        assert is_forced
-
-    def test_unknown_language_returns_none(self, tmp_path):
-        p = tmp_path / "Show.S01E01.720p.srt"
-        p.write_text("")
-        lang, _, _ = _classify(p)
-        assert lang is None
-
-    def test_dot_separator(self, tmp_path):
-        p = tmp_path / "fre.sdh.srt"
-        p.write_text("")
-        lang, is_sdh, _ = _classify(p)
-        assert lang == "fre"
-        assert is_sdh
-
-    def test_hyphen_separator(self, tmp_path):
-        p = tmp_path / "fre-forced.srt"
-        p.write_text("")
-        lang, _, is_forced = _classify(p)
-        assert lang == "fre"
-        assert is_forced
-
-
-# ---------------------------------------------------------------------------
-# SubtitleCandidate.destination_name
-# ---------------------------------------------------------------------------
-
-
-class TestSubtitleCandidateDestinationName:
-    def _make(self, lang="fre", is_sdh=False, is_forced=False, ext=".srt", path=None):
-        return SubtitleCandidate(
-            source_path=path or Path("/fake/fre.srt"),
-            language=lang,
-            is_sdh=is_sdh,
-            is_forced=is_forced,
-            extension=ext,
-        )
-
-    def test_standard(self):
-        assert self._make().destination_name == "fre.srt"
-
-    def test_sdh(self):
-        assert self._make(is_sdh=True).destination_name == "fre.sdh.srt"
-
-    def test_forced(self):
-        assert self._make(is_forced=True).destination_name == "fre.forced.srt"
-
-    def test_ass_extension(self):
-        assert self._make(ext=".ass").destination_name == "fre.ass"
-
-    def test_english_standard(self):
-        assert self._make(lang="eng").destination_name == "eng.srt"
-
-
-# ---------------------------------------------------------------------------
-# SubtitleScanner — integration with real filesystem
-# ---------------------------------------------------------------------------
-
-
-class TestSubtitleScanner:
-    def _scanner(self, languages=None, min_size_kb=0, keep_sdh=True, keep_forced=True):
-        return SubtitleScanner(
-            languages=languages or ["fre", "eng"],
-            min_size_kb=min_size_kb,
-            keep_sdh=keep_sdh,
-            keep_forced=keep_forced,
-        )
-
-    def _video(self, tmp_path):
-        video = tmp_path / "Movie.mkv"
-        video.write_bytes(b"video")
-        return video
-
-    def test_finds_adjacent_subtitle(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "fre.srt").write_text("subtitle content")
-
-        candidates = self._scanner().scan(video)
-
-        assert len(candidates) == 1
-        assert candidates[0].language == "fre"
-
-    def test_finds_adjacent_subtitle_legacy_639_1(self, tmp_path):
-        # Reading existing media libraries: ``fr.srt`` is still recognized as
-        # French and classified canonically as ``fre`` — covers user libraries
-        # written before the ISO 639-2/B migration.
-        video = self._video(tmp_path)
-        (tmp_path / "fr.srt").write_text("subtitle content")
-
-        candidates = self._scanner().scan(video)
-
-        assert len(candidates) == 1
-        assert candidates[0].language == "fre"
-
-    def test_finds_multiple_languages(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "fre.srt").write_text("fr subtitle")
-        (tmp_path / "eng.srt").write_text("en subtitle")
-
-        candidates = self._scanner().scan(video)
-        langs = {c.language for c in candidates}
-        assert langs == {"fre", "eng"}
-
-    def test_scans_subs_subfolder(self, tmp_path):
-        video = self._video(tmp_path)
-        subs = tmp_path / "Subs"
-        subs.mkdir()
-        (subs / "fre.srt").write_text("subtitle")
-
-        candidates = self._scanner().scan(video)
-        assert any(c.language == "fre" for c in candidates)
-
-    def test_filters_unknown_language(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "unknown.srt").write_text("subtitle")
-
-        candidates = self._scanner().scan(video)
-        assert len(candidates) == 0
-
-    def test_filters_wrong_language(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "ger.srt").write_text("german subtitle")
-
-        candidates = self._scanner(languages=["fre"]).scan(video)
-        assert len(candidates) == 0
-
-    def test_filters_too_small_file(self, tmp_path):
-        video = self._video(tmp_path)
-        small = tmp_path / "fre.srt"
-        small.write_bytes(b"x")  # 1 byte, well below any min_size_kb
-
-        candidates = self._scanner(min_size_kb=10).scan(video)
-        assert len(candidates) == 0
-
-    def test_filters_sdh_when_not_wanted(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "fre.sdh.srt").write_text("sdh subtitle")
-
-        candidates = self._scanner(keep_sdh=False).scan(video)
-        assert len(candidates) == 0
-
-    def test_filters_forced_when_not_wanted(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "fre.forced.srt").write_text("forced subtitle")
-
-        candidates = self._scanner(keep_forced=False).scan(video)
-        assert len(candidates) == 0
-
-    def test_keeps_sdh_when_wanted(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "fre.sdh.srt").write_text("sdh subtitle")
-
-        candidates = self._scanner(keep_sdh=True).scan(video)
-        assert len(candidates) == 1
-        assert candidates[0].is_sdh
-
-    def test_ignores_non_subtitle_files(self, tmp_path):
-        video = self._video(tmp_path)
-        (tmp_path / "fre.nfo").write_text("nfo file")
-        (tmp_path / "fre.jpg").write_bytes(b"image")
-
-        candidates = self._scanner().scan(video)
-        assert len(candidates) == 0
-
-    def test_returns_empty_when_no_subtitles(self, tmp_path):
-        video = self._video(tmp_path)
-        candidates = self._scanner().scan(video)
-        assert candidates == []

tests/domain/test_subtitle_utils.py

@@ -30,9 +30,19 @@ from alfred.domain.subtitles.value_objects import (
     RuleScope,
     SubtitleFormat,
     SubtitleLanguage,
+    SubtitleMatchingRules,
     SubtitleType,
 )
 
+# Test fixture: stand-in for what the KB would provide at runtime.
+_DEFAULT_RULES = SubtitleMatchingRules(
+    preferred_languages=["eng"],
+    preferred_formats=["srt"],
+    allowed_types=["standard"],
+    format_priority=["srt", "ass"],
+    min_confidence=0.7,
+)
+
 # --------------------------------------------------------------------------- #
 # Value objects                                                                #
 # --------------------------------------------------------------------------- #
@@ -230,18 +240,17 @@ class TestAvailableSubtitles:
 
 
 class TestSubtitleRuleSet:
-    def test_global_default_uses_kb_defaults(self):
+    def test_global_default_returns_injected_defaults(self):
         rs = SubtitleRuleSet.global_default()
-        rules = rs.resolve()
-        # Loaded from subtitles.yaml — defaults must be non-empty.
-        assert rules.preferred_languages
-        assert rules.preferred_formats
-        assert 0 < rules.min_confidence <= 1
+        rules = rs.resolve(_DEFAULT_RULES)
+        assert rules.preferred_languages == _DEFAULT_RULES.preferred_languages
+        assert rules.preferred_formats == _DEFAULT_RULES.preferred_formats
+        assert rules.min_confidence == _DEFAULT_RULES.min_confidence
 
     def test_override_persists(self):
         rs = SubtitleRuleSet.global_default()
         rs.override(languages=["eng"], min_confidence=0.9)
-        rules = rs.resolve()
+        rules = rs.resolve(_DEFAULT_RULES)
         assert rules.preferred_languages == ["eng"]
         assert rules.min_confidence == 0.9
 
@@ -252,10 +261,10 @@ class TestSubtitleRuleSet:
             parent=parent,
         )
         child.override(languages=["jpn"])
-        rules = child.resolve()
+        rules = child.resolve(_DEFAULT_RULES)
         assert rules.preferred_languages == ["jpn"]
         # min_confidence not overridden at child or parent → falls back to defaults
-        assert rules.min_confidence == parent.resolve().min_confidence
+        assert rules.min_confidence == parent.resolve(_DEFAULT_RULES).min_confidence
 
     def test_to_dict_only_emits_set_deltas(self):
         rs = SubtitleRuleSet(scope=RuleScope(level="show", identifier="tt1"))
@@ -286,4 +295,4 @@ class TestSubtitleRuleSet:
         # code uses `is not None` explicitly. Verify 0.0 doesn't fall back.
         rs = SubtitleRuleSet.global_default()
         rs.override(min_confidence=0.0)
-        assert rs.resolve().min_confidence == 0.0
+        assert rs.resolve(_DEFAULT_RULES).min_confidence == 0.0

tests/domain/test_tv_shows.py

@@ -157,10 +157,9 @@ class TestEpisode:
         assert filename.startswith("S01E05")
         assert "Gray.Matter" in filename
 
-    def test_has_file_false_when_no_path(self):
+    def test_file_path_unset_by_default(self):
         e = self._ep()
-        assert not e.has_file()
-        assert not e.is_downloaded()
+        assert e.file_path is None
 
     def test_str_format(self):
         e = self._ep(season=2, episode=3, title="Bit by a Dead Bee")

tests/infrastructure/test_rule_repository.py

@@ -17,6 +17,7 @@ from pathlib import Path
 
 import yaml
 
+from alfred.domain.subtitles.value_objects import SubtitleMatchingRules
 from alfred.infrastructure.persistence.memory.ltm.components.subtitle_preferences import (
     SubtitlePreferences,
 )
@@ -25,6 +26,15 @@ from alfred.infrastructure.subtitle.rule_repository import (
     _filter_override,
 )
 
+# Stand-in for KB defaults, injected at resolve().
+_DEFAULT_RULES = SubtitleMatchingRules(
+    preferred_languages=["eng"],
+    preferred_formats=["srt"],
+    allowed_types=["standard"],
+    format_priority=["srt", "ass"],
+    min_confidence=0.7,
+)
+
 
 def _write(path: Path, data: dict) -> None:
     path.parent.mkdir(parents=True, exist_ok=True)
@@ -71,17 +81,17 @@ class TestLoad:
     def test_no_files_returns_global_default(self, tmp_path):
         repo = RuleSetRepository(tmp_path)
         rs = repo.load()
-        # Should resolve cleanly using the hardcoded defaults.
-        rules = rs.resolve()
-        assert rules.preferred_languages  # non-empty
-        assert rules.min_confidence > 0
+        # With no overrides, resolve returns the injected defaults unchanged.
+        rules = rs.resolve(_DEFAULT_RULES)
+        assert rules.preferred_languages == _DEFAULT_RULES.preferred_languages
+        assert rules.min_confidence == _DEFAULT_RULES.min_confidence
 
     def test_subtitle_preferences_override_base(self, tmp_path):
         prefs = SubtitlePreferences(
             languages=["jpn"], formats=["ass"], types=["standard"]
         )
         repo = RuleSetRepository(tmp_path)
-        rules = repo.load(subtitle_preferences=prefs).resolve()
+        rules = repo.load(subtitle_preferences=prefs).resolve(_DEFAULT_RULES)
         assert rules.preferred_languages == ["jpn"]
         assert rules.preferred_formats == ["ass"]
         assert rules.allowed_types == ["standard"]
@@ -92,7 +102,7 @@ class TestLoad:
             {"override": {"languages": ["spa"], "min_confidence": 0.95}},
         )
         repo = RuleSetRepository(tmp_path)
-        rules = repo.load().resolve()
+        rules = repo.load().resolve(_DEFAULT_RULES)
         assert rules.preferred_languages == ["spa"]
         assert rules.min_confidence == 0.95
 
@@ -102,7 +112,7 @@ class TestLoad:
             {"override": {"format_priority": ["ass", "srt"]}},
         )
         repo = RuleSetRepository(tmp_path)
-        rules = repo.load(release_group="KONTRAST").resolve()
+        rules = repo.load(release_group="KONTRAST").resolve(_DEFAULT_RULES)
         assert rules.format_priority == ["ass", "srt"]
 
     def test_full_three_level_chain(self, tmp_path):
@@ -119,7 +129,9 @@ class TestLoad:
             {"override": {"min_confidence": 0.99}},
         )
         repo = RuleSetRepository(tmp_path)
-        rules = repo.load(release_group="GRP", subtitle_preferences=prefs).resolve()
+        rules = repo.load(release_group="GRP", subtitle_preferences=prefs).resolve(
+            _DEFAULT_RULES
+        )
         # All three levels visible — local overrides on top
         assert rules.preferred_languages == ["jpn"]
         assert rules.format_priority == ["ass"]

tests/infrastructure/test_subtitle_metadata_store.py

@@ -17,7 +17,7 @@ from __future__ import annotations
 from pathlib import Path
 
 from alfred.domain.subtitles.entities import SubtitleCandidate
-from alfred.domain.subtitles.services.placer import PlacedTrack
+from alfred.application.subtitles.placer import PlacedTrack
 from alfred.domain.subtitles.value_objects import (
     SubtitleFormat,
     SubtitleLanguage,