Add POST endpoint for /login

endpoints/login.post.py

@@ -1,13 +1,11 @@
 # Entity: User
 
-```python
 from fastapi import APIRouter, Depends, HTTPException, status
 from sqlalchemy.orm import Session
 from core.database import get_db
 from models.user import User
 from schemas.user import UserSchema, UserLogin
-from helpers.user_helpers import authenticate_user
-from core.security import create_access_token
+from helpers.user_helpers import authenticate_user, create_access_token
 
 router = APIRouter()
 
@@ -16,15 +14,13 @@ async def login(
     user_credentials: UserLogin,
     db: Session = Depends(get_db)
 ):
-    """Authenticate user and return access token"""
-    user = authenticate_user(db, user_credentials.email, user_credentials.password)
+    user = authenticate_user(db, user_credentials.username, user_credentials.password)
     if not user:
         raise HTTPException(
             status_code=status.HTTP_401_UNAUTHORIZED,
-            detail="Incorrect email or password",
+            detail="Incorrect username or password",
             headers={"WWW-Authenticate": "Bearer"},
         )
     
-    access_token = create_access_token(data={"sub": user.email})
+    access_token = create_access_token(data={"sub": user.username})
     return {"access_token": access_token, "token_type": "bearer"}
-```