init

app/routers/friends.py

@@ -0,0 +1,91 @@
+import uuid
+
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlmodel import Session, select
+
+from app.database import get_session
+from app.models.user import User
+from app.models.friendship import Friendship
+from app.schemas.user import UserRead
+from app.auth.dependencies import get_current_user
+
+router = APIRouter(prefix="/friends", tags=["friends"])
+
+
+@router.post("", status_code=status.HTTP_201_CREATED)
+def add_friend(
+    username: str,
+    current_user: User = Depends(get_current_user),
+    session: Session = Depends(get_session),
+):
+    """Add a friend by username. Creates bidirectional friendship."""
+    friend = session.exec(select(User).where(User.username == username)).first()
+    if not friend:
+        raise HTTPException(status_code=404, detail="User not found")
+    if friend.id == current_user.id:
+        raise HTTPException(status_code=400, detail="Cannot add yourself")
+
+    # Check if already friends
+    existing = session.exec(
+        select(Friendship).where(
+            Friendship.user_id == current_user.id,
+            Friendship.friend_id == friend.id,
+        )
+    ).first()
+    if existing:
+        raise HTTPException(status_code=400, detail="Already friends")
+
+    # Bidirectional
+    session.add(Friendship(user_id=current_user.id, friend_id=friend.id))
+    session.add(Friendship(user_id=friend.id, friend_id=current_user.id))
+    session.commit()
+
+    return {"detail": f"Now friends with {friend.username}"}
+
+
+@router.get("", response_model=list[UserRead])
+def list_friends(
+    current_user: User = Depends(get_current_user),
+    session: Session = Depends(get_session),
+):
+    """List all friends of the current user."""
+    friend_ids = session.exec(
+        select(Friendship.friend_id).where(Friendship.user_id == current_user.id)
+    ).all()
+
+    if not friend_ids:
+        return []
+
+    friends = session.exec(
+        select(User).where(User.id.in_(friend_ids))  # type: ignore[union-attr]
+    ).all()
+    return friends
+
+
+@router.delete("/{friend_id}", status_code=status.HTTP_204_NO_CONTENT)
+def remove_friend(
+    friend_id: uuid.UUID,
+    current_user: User = Depends(get_current_user),
+    session: Session = Depends(get_session),
+):
+    """Remove a friend (bidirectional)."""
+    f1 = session.exec(
+        select(Friendship).where(
+            Friendship.user_id == current_user.id,
+            Friendship.friend_id == friend_id,
+        )
+    ).first()
+    f2 = session.exec(
+        select(Friendship).where(
+            Friendship.user_id == friend_id,
+            Friendship.friend_id == current_user.id,
+        )
+    ).first()
+
+    if not f1:
+        raise HTTPException(status_code=404, detail="Friendship not found")
+
+    session.delete(f1)
+    if f2:
+        session.delete(f2)
+    session.commit()