Add engine abstraction

src/vector_search_mcp/engine/base_engine.py

@@ -0,0 +1,43 @@
+from abc import ABC, abstractmethod
+from typing import Generic, TypeVar
+
+from ..models import Condition, SearchRow
+
+ResponseType = TypeVar("ResponseType")
+ConditionType = TypeVar("ConditionType")
+
+__all__ = ["BaseEngine"]
+
+
+class BaseEngine(ABC, Generic[ResponseType, ConditionType]):
+    @abstractmethod
+    def transform_conditions(
+        self, conditions: list[Condition] | None
+    ) -> ConditionType | None: ...
+
+    @abstractmethod
+    def transform_response(self, response: ResponseType) -> list[SearchRow]: ...
+
+    @abstractmethod
+    async def run_similarity_query(
+        self,
+        embedding: list[float],
+        collection: str,
+        limit: int = 10,
+        conditions: ConditionType | None = None,
+        threshold: float | None = None,
+    ) -> ResponseType: ...
+
+    async def semantic_search(
+        self,
+        vector: list[float],
+        collection: str,
+        limit: int = 10,
+        conditions: list[Condition] | None = None,
+        threshold: float | None = None,
+    ) -> list[SearchRow]:
+        transformed_conditions = self.transform_conditions(conditions)
+        response = await self.run_similarity_query(
+            vector, collection, limit, transformed_conditions, threshold
+        )
+        return self.transform_response(response)