Refactor code structure for improved readability and maintainability

app/models/user_oauth.py

@@ -0,0 +1,34 @@
+from typing import TYPE_CHECKING
+
+from sqlmodel import Field, Relationship, UniqueConstraint
+
+from app.models.base import BaseModel
+
+if TYPE_CHECKING:
+    from app.models.user import User
+
+
+class UserOauth(BaseModel, table=True):
+    """Database model for a user OAuth."""
+
+    __tablename__ = "user_oauth"  # pyright: ignore[reportAssignmentType]
+
+    user_id: int = Field(foreign_key="user.id", nullable=False)
+    provider: str = Field(nullable=False)
+    provider_user_id: str = Field(nullable=False)
+    email: str = Field(nullable=False)
+    name: str = Field(nullable=False)
+    picture: str | None = Field(default=None)
+
+
+    # constraints
+    __table_args__ = (
+        UniqueConstraint(
+            "provider",
+            "provider_user_id",
+            name="uq_user_oauth_provider_user_id",
+        ),
+    )
+
+    # relationships
+    user: "User" = Relationship(back_populates="oauths")