First product

app/auth/service.py

@@ -0,0 +1,38 @@
+from __future__ import annotations
+
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.auth.security import PasswordService
+from app.db.models import User
+
+
+class AuthService:
+    def __init__(self, password_service: PasswordService) -> None:
+        self._password_service = password_service
+
+    async def authenticate_user(
+        self,
+        db_session: AsyncSession,
+        *,
+        email: str,
+        password: str,
+    ) -> User | None:
+        normalized_email = email.strip().lower()
+        if not normalized_email or not password:
+            return None
+        result = await db_session.execute(
+            select(User).where(User.email == normalized_email)
+        )
+        user = result.scalar_one_or_none()
+        if user is None or not user.is_active:
+            return None
+        if not self._password_service.verify_password(user.password_hash, password):
+            return None
+        return user
+
+    def hash_password(self, password: str) -> str:
+        return self._password_service.hash_password(password)
+
+    def verify_password(self, *, password_hash: str, password: str) -> bool:
+        return self._password_service.verify_password(password_hash, password)