"""
/user endpoints.
"""

from fastapi import APIRouter, Depends, HTTPException, status
from fastapi.security import OAuth2PasswordRequestForm
from pydantic import BaseModel

from ..config import Config
from ..db import User, UserCapabilityType, UserCreate, UserRead
from ._common import Responses, get_current_user, get_current_user_if_admin

router = APIRouter(prefix="/user", tags=["user"])


class Token(BaseModel):
    """
    Response model for issuing tokens.
    """

    access_token: str
    token_type: str


@router.post("/authenticate", response_model=Token)
async def login(
    form_data: OAuth2PasswordRequestForm = Depends(),
    current_config: Config | None = Depends(Config.load),
):
    """
    POST ./authenticate: Authenticate a user. Issues a bearer token.
    """

    # fail if not installed
    if current_config is None:
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST)

    # try logging in
    if not (user := User.authenticate(
        name=form_data.username,
        password=form_data.password,
    )):
        # authentication failed
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Could not validate credentials",
            headers={"WWW-Authenticate": "Bearer"},
        )

    if not user.can(UserCapabilityType.login):
        # user cannot login
        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN)

    # authentication succeeded
    access_token = await current_config.jwt.create_token(user.name)
    return {"access_token": access_token, "token_type": "bearer"}


@router.get("/current", response_model=UserRead)
async def get_current_user(
    current_user: User | None = Depends(get_current_user),
):
    """
    GET ./current: Respond with the currently logged-in user.
    """

    return current_user


@router.post(
    "",
    responses={
        status.HTTP_200_OK: Responses.OK,
        status.HTTP_400_BAD_REQUEST: Responses.NOT_INSTALLED,
        status.HTTP_401_UNAUTHORIZED: Responses.NEEDS_USER,
        status.HTTP_403_FORBIDDEN: Responses.NEEDS_ADMIN,
        status.HTTP_409_CONFLICT: Responses.ENTRY_EXISTS,
    },
    response_model=UserRead,
)
async def add_user(
    user: UserCreate,
    _: User = Depends(get_current_user_if_admin),
) -> User:
    """
    POST ./: Create a new user in the database.
    """

    # actually create the new user
    new_user = User.create(user=user)

    # fail if creation was unsuccessful
    if new_user is None:
        raise HTTPException(status_code=status.HTTP_409_CONFLICT)

    new_user.set_capabilities([UserCapabilityType.login])
    new_user.update()

    # return the created user on success
    return new_user


@router.delete(
    "/{user_name}",
    responses={
        status.HTTP_200_OK: Responses.OK,
        status.HTTP_400_BAD_REQUEST: Responses.NOT_INSTALLED,
        status.HTTP_401_UNAUTHORIZED: Responses.NEEDS_USER,
        status.HTTP_403_FORBIDDEN: Responses.NEEDS_ADMIN,
        status.HTTP_404_NOT_FOUND: Responses.ENTRY_DOESNT_EXIST,
    },
    response_model=User,
)
async def remove_user(
    user_name: str,
    _: User = Depends(get_current_user_if_admin),
):
    """
    DELETE ./{user_name}: Remove a user from the database.
    """

    # get the user
    user = User.get(user_name)

    # fail if user not found
    if user is None:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND)

    # delete user
    user.delete()


@router.post(
    "/{user_name}/capabilities",
    responses={
        status.HTTP_200_OK: Responses.OK,
        status.HTTP_400_BAD_REQUEST: Responses.NOT_INSTALLED,
        status.HTTP_401_UNAUTHORIZED: Responses.NEEDS_USER,
        status.HTTP_403_FORBIDDEN: Responses.NEEDS_ADMIN,
    },
)
async def extend_capabilities(
    user_name: str,
    capabilities: list[UserCapabilityType],
    _: User = Depends(get_current_user_if_admin),
):
    """
    POST ./{user_name}/capabilities: Add capabilities to a user.
    """

    # get and change the user
    user = User.get(user_name)

    user.set_capabilities(user.get_capabilities() | set(capabilities))

    user.update()


@router.delete(
    "/{user_name}/capabilities",
    responses={
        status.HTTP_200_OK: Responses.OK,
        status.HTTP_400_BAD_REQUEST: Responses.NOT_INSTALLED,
        status.HTTP_401_UNAUTHORIZED: Responses.NEEDS_USER,
        status.HTTP_403_FORBIDDEN: Responses.NEEDS_ADMIN,
    },
)
async def remove_capabilities(
    user_name: str,
    capabilities: list[UserCapabilityType],
    _: User = Depends(get_current_user_if_admin),
):
    """
    DELETE ./{user_name}/capabilities: Remove capabilities from a user.
    """

    # get and change the user
    user = User.get(user_name)

    user.set_capabilities(user.get_capabilities() - set(capabilities))

    user.update()