refactor: 推进后端分层架构治理

app/application/subscription/query.py

@@ -0,0 +1,76 @@
+"""订阅存在性、来源定位和类型状态查询应用服务。"""
+
+from __future__ import annotations
+
+from typing import Any, Optional, Protocol
+
+from app.domain.context import MediaInfo
+from app.domain.meta.metabase import MetaBase
+from app.schemas.media import resolve_media_identity
+from app.schemas.types import MediaType
+
+
+class SubscriptionQueryRepository(Protocol):
+    """描述订阅查询切片所需的最小仓储能力。"""
+
+    def exists(self, **identity: Any) -> bool:
+        """按完整订阅身份判断记录是否存在。"""
+        ...
+
+    def get_by(self, **identity: Any) -> Optional[Any]:
+        """按来源关键字中的订阅身份读取单条记录。"""
+        ...
+
+    def list(self, state: Optional[str] = None) -> list[Any]:
+        """按可选状态集合读取订阅记录。"""
+        ...
+
+
+class SubscriptionQueryService:
+    """封装不修改订阅状态的三个公开查询用例。"""
+
+    _SOURCE_FIELDS = {
+        "type",
+        "season",
+        "media_source",
+        "media_id",
+        "music_type",
+    }
+
+    def __init__(self, repository: SubscriptionQueryRepository) -> None:
+        """保存订阅查询仓储端口。"""
+        self._repository = repository
+
+    def exists(
+        self,
+        mediainfo: MediaInfo,
+        meta: Optional[MetaBase] = None,
+    ) -> bool:
+        """按媒体身份、季、剧集组和音乐实体类型判断订阅是否存在。"""
+        media_source, media_id = resolve_media_identity(media=mediainfo)
+        return bool(self._repository.exists(
+            media_source=media_source,
+            media_id=media_id,
+            music_type=getattr(mediainfo, "music_type", None)
+            if mediainfo.type == MediaType.MUSIC else None,
+            season=meta.begin_season if meta else None,
+            episode_group=mediainfo.episode_group,
+        ))
+
+    def get_by_source(self, source_keyword: Optional[dict]) -> Optional[Any]:
+        """从已解析来源关键字筛出稳定身份字段并读取订阅。"""
+        if not source_keyword:
+            return None
+        identity = {
+            key: value
+            for key, value in source_keyword.items()
+            if key in self._SOURCE_FIELDS
+        }
+        return self._repository.get_by(**identity)
+
+    def has_music(self, searchable_states: str) -> bool:
+        """判断给定可搜索状态内是否至少存在一个音乐订阅。"""
+        return any(
+            subscribe.type == MediaType.MUSIC.value
+            for subscribe in self._repository.list(searchable_states) or []
+        )