"""
/device endpoints.
"""

from fastapi import APIRouter, Depends, HTTPException, status
from kiwi_vpn_api.db.device import DeviceStatus

from ..db import Device, DeviceCreate, DeviceRead, User
from ..easyrsa import EASYRSA, DistinguishedName
from ._common import (Responses, get_current_user, get_device_by_id,
                      get_user_by_name)

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


@router.post(
    "/{user_name}",
    responses={
        status.HTTP_201_CREATED: Responses.ENTRY_ADDED,
        status.HTTP_400_BAD_REQUEST: Responses.NOT_INSTALLED,
        status.HTTP_401_UNAUTHORIZED: Responses.NEEDS_USER,
        status.HTTP_403_FORBIDDEN: Responses.NEEDS_PERMISSION,
        status.HTTP_409_CONFLICT: Responses.ENTRY_EXISTS,
    },
    response_model=DeviceRead,
    status_code=status.HTTP_201_CREATED,
)
async def add_device(
    device: DeviceCreate,
    current_user: User = Depends(get_current_user),
    owner: User = Depends(get_user_by_name),
) -> Device:
    """
    POST ./: Create a new device in the database.

    Status:

    - 403: no user permission to create device
    - 409: device creation unsuccessful
    """

    # check permissions
    try:
        current_user.check_create(Device, owner)

    except PermissionError as e:
        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN) from e

    # create the new device
    new_device = Device.create(
        owner=owner,
        device=device,
    )

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

    # return the created device on success
    return new_device


@router.delete(
    "/{device_id}",
    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_PERMISSION,
        status.HTTP_404_NOT_FOUND: Responses.ENTRY_DOESNT_EXIST,
    },
    response_model=User,
)
async def remove_device(
    current_user: User = Depends(get_current_user),
    device: Device = Depends(get_device_by_id),
):
    """
    DELETE ./{device_id}: Remove a device from the database.

    Status:

    - 403: no user permission to edit device
    """

    # check permissions
    try:
        current_user.check_edit(device)

    except PermissionError as e:
        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN) from e

    # delete device
    device.delete()


@router.post(
    "/{device_id}/issue",
    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_PERMISSION,
        status.HTTP_404_NOT_FOUND: Responses.ENTRY_DOESNT_EXIST,
        status.HTTP_409_CONFLICT: Responses.ENTRY_EXISTS,
    },
    response_model=DeviceRead,
)
async def request_certificate_issuance(
    current_user: User = Depends(get_current_user),
    device: Device = Depends(get_device_by_id),
) -> Device:
    """
    POST ./{device_id}/issue: Request certificate issuance for a device.

    Status:

    - 403: no user permission to edit device
    - 409: device certificate cannot be "issued"
    """

    # check permissions
    try:
        current_user.check_edit(device)

    except PermissionError as e:
        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN) from e

    # can only "request" on an uncertified device
    if device.status is not DeviceStatus.uncertified:
        raise HTTPException(status_code=status.HTTP_409_CONFLICT)

    device.set_status(DeviceStatus.pending)

    # check if we can issue the certificate immediately
    if current_user.can_issue:
        if (certificate := EASYRSA.issue(
            dn=DistinguishedName.build(device)
        )) is not None:
            device.set_status(DeviceStatus.certified)
            device.expiry = certificate.not_valid_after

    # return updated device
    device.update()
    return device


@router.post(
    "/{device_id}/renew",
    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_PERMISSION,
        status.HTTP_404_NOT_FOUND: Responses.ENTRY_DOESNT_EXIST,
        status.HTTP_409_CONFLICT: Responses.ENTRY_EXISTS,
    },
    response_model=DeviceRead,
)
async def request_certificate_renewal(
    current_user: User = Depends(get_current_user),
    device: Device = Depends(get_device_by_id),
) -> Device:
    """
    POST ./{device_id}/renew: Request certificate renewal for a device.

    Status:

    - 403: no user permission to edit device
    - 409: device certificate cannot be "renewed"
    """

    # check permissions
    try:
        current_user.check_edit(device)

    except PermissionError as e:
        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN) from e

    # can only "renew" on an already certified device
    if device.status is not DeviceStatus.certified:
        raise HTTPException(status_code=status.HTTP_409_CONFLICT)

    device.set_status(DeviceStatus.pending)

    # check if we can renew the certificate immediately
    if current_user.can_renew:
        if (certificate := EASYRSA.renew(
            dn=DistinguishedName.build(device)
        )) is not None:
            device.set_status(DeviceStatus.certified)
            device.expiry = certificate.not_valid_after

    # return updated device
    device.update()
    return device


@router.post(
    "/{device_id}/revoke",
    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_PERMISSION,
        status.HTTP_404_NOT_FOUND: Responses.ENTRY_DOESNT_EXIST,
        status.HTTP_409_CONFLICT: Responses.ENTRY_EXISTS,
    },
    response_model=DeviceRead,
)
async def revoke_certificate(
    current_user: User = Depends(get_current_user),
    device: Device = Depends(get_device_by_id),
) -> Device:
    """
    POST ./{device_id}/revoke: Revoke a device certificate.

    Status:

    - 403: no user permission to edit device
    - 409: device certificate cannot be "revoked"
    """

    # check permissions
    try:
        current_user.check_edit(device)

    except PermissionError as e:
        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN) from e

    # can only "revoke" on a currently certified device
    if device.status is not DeviceStatus.certified:
        raise HTTPException(status_code=status.HTTP_409_CONFLICT)

    # revoke the device certificate
    EASYRSA.revoke(dn=DistinguishedName.build(device))

    # reset the device
    device.set_status(DeviceStatus.uncertified)
    device.expiry = None

    # return updated device
    device.update()
    return device