"""Flask application which provides the interface of a login panel. The
application interacts with different backend, like the Kratos backend for users,
Hydra for OIDC sessions and MariaDB for application and role specifications.
The application provides also several command line options to interact with
the user entries in the database(s)"""


# Basic system imports
import logging
import os
import urllib.parse
import urllib.request

import click

# Hydra, OIDC Identity Provider
import hydra_client

# Kratos, Identity manager
import ory_kratos_client
#from exceptions import BackendError

# Flask
from flask import Flask, abort, redirect, render_template, request
from flask.cli import AppGroup
from ory_kratos_client.api import v0alpha2_api as kratos_api

from areas import cli
from config import *
from flask import current_app

from helpers import (
    BadRequest,
    KratosError,
    HydraError,
    bad_request_error,
    validation_error,
    kratos_error,
    global_error,
    hydra_error,
    KratosUser,
    App,
    AppRole
)

from database import db

# APIs
# Create HYDRA & KRATOS API interfaces
HYDRA = hydra_client.HydraAdmin(HYDRA_ADMIN_URL)

# Kratos has an admin and public end-point. We create an API for them
# both. The kratos implementation has bugs, which forces us to set
# the discard_unknown_keys to True.
tmp = ory_kratos_client.Configuration(host=KRATOS_ADMIN_URL,
                                        discard_unknown_keys= True)
KRATOS_ADMIN = kratos_api.V0alpha2Api(ory_kratos_client.ApiClient(tmp))

tmp = ory_kratos_client.Configuration(host=KRATOS_PUBLIC_URL,
                                      discard_unknown_keys = True)
KRATOS_PUBLIC = kratos_api.V0alpha2Api(ory_kratos_client.ApiClient(tmp))

##############################################################################
# CLI INTERFACE                                                              #
##############################################################################
# Define Flask CLI command groups and commands
user_cli = AppGroup('user')
app_cli = AppGroup('app')

## CLI APP COMMANDS

@app_cli.command('create')
@click.argument('slug')
@click.argument('name')
def create_app(slug, name):
    """Adds an app into the database
    :param slug: str short name of the app
    :param name: str name of the application
    """
    current_app.logger.info(f"Creating app definition: {name} ({slug})")

    obj = App()
    obj.name = name
    obj.slug = slug

    db.session.add(obj)
    db.session.commit()



@app_cli.command('list')
def list_app():
    """List all apps found in the database"""
    current_app.logger.info("Listing configured apps")
    apps = App.query.all()

    for obj in apps:
        print(f"App name: {obj.name} \t Slug: {obj.slug}")


@app_cli.command('delete',)
@click.argument('slug')
def delete_app(slug):
    """Removes app from database
    :param slug: str Slug of app to remove
    """
    current_app.logger.info(f"Trying to delete app: {slug}")
    obj = App.query.filter_by(slug=slug).first()

    if not obj:
        current_app.logger.info("Not found")
        return


    # Deleting will (probably) fail if there are still roles attached. This is a
    # PoC implementation only. Actually management of apps and roles will be
    # done by the backend application
    db.session.delete(obj)
    db.session.commit()
    current_app.logger.info("Success")
    return


cli.cli.add_command(app_cli)


## CLI USER COMMANDS
@user_cli.command("setrole")
@click.argument("email")
@click.argument("app_slug")
@click.argument("role")
def setrole(email, app_slug, role):
    """Set role for a sure
    :param email: Email address of user to assign role
    :param app_slug: Slug name of the app, for example 'nextcloud'
    :param role: Role to assign. currently only 'admin', 'user'
    """

    current_app.logger.info(f"Assiging role {role} to {email} for app {app_slug}")

    # Find user
    user = KratosUser.find_by_email(KRATOS_ADMIN, email)

    if role not in ("admin", "user"):
        print("At this point only the roles 'admin' and 'user' are accepted")
        return

    if not user:
        print("User not found. Abort")
        return

    app_obj = db.session.query(App).filter(App.slug == app_slug).first()
    if not app_obj:
        print("App not found. Abort.")
        return

    role_obj = (
        db.session.query(AppRole)
        .filter(AppRole.app_id == app_obj.id)
        .filter(AppRole.user_id == user.uuid)
        .first()
    )

    if role_obj:
        db.session.delete(role_obj)

    obj = AppRole()
    obj.user_id = user.uuid
    obj.app_id = app_obj.id
    obj.role = role

    db.session.add(obj)
    db.session.commit()


@user_cli.command("show")
@click.argument("email")
def show_user(email):
    """Show user details. Output a table with the user and details about the
    internal state/values of the user object
    :param email: Email address of the user to show
    """
    user = KratosUser.find_by_email(KRATOS_ADMIN, email)
    print(user)
    print("")
    print(f"UUID:     {user.uuid}")
    print(f"Username: {user.username}")
    print(f"Updated:  {user.updated_at}")
    print(f"Created:  {user.created_at}")
    print(f"State:    {user.state}")

@user_cli.command('update')
@click.argument('email')
@click.argument('field')
@click.argument('value')
def update_user(email, field, value):
    """Update an user object. It can modify email and name currently
    :param email: Email address of user to update
    :param field: Field to update, supported [name|email]
    :param value: The value to set the field with
    """
    current_app.logger.info(f"Looking for user with email: {email}")
    user = KratosUser.find_by_email(KRATOS_ADMIN, email)
    if not user:
        current_app.logger.error(f"User with email {email} not found.")
        return

    if field == 'name':
        user.name = value
    elif field == 'email':
        user.email = value
    else:
        current_app.logger.error(f"Field not found: {field}")

    user.save()


@user_cli.command('delete')
@click.argument('email')
def delete_user(email):
    """Delete an user from the database
    :param email: Email address of user to delete
    """
    current_app.logger.info(f"Looking for user with email: {email}")
    user = KratosUser.find_by_email(KRATOS_ADMIN, email)
    if not user:
        current_app.logger.error(f"User with email {email} not found.")
        return
    user.delete()



@user_cli.command('create')
@click.argument('email')
def create_user(email):
    """Create a user in the kratos database. The argument must be an unique
    email address
    :param email: string Email address of user to add
    """
    current_app.logger.info(f"Creating user with email: ({email})")

    # Create a user
    user = KratosUser.find_by_email(KRATOS_ADMIN, email)
    if user:
        current_app.logger.info("User already exists. Not recreating")
        return

    user = KratosUser(KRATOS_ADMIN)
    user.email = email
    user.save()

@user_cli.command('setpassword')
@click.argument('email')
@click.argument('password')
def setpassword_user(email, password):
    """Set a password for an account
    :param email:    email address of account to set a password for
    :param password:  password to be set
    :return:         true on success, false if not set (too weak)
    :rtype: boolean
    :raise:          exception if unexepted error happens
    """

    current_app.logger.info(f"Setting password for: ({email})")

    # Kratos does not provide an interface to set a password directly. However
    # we still want to be able to set a password. So we have to hack our way
    # a bit around this. We do this by creating a recovery link though the
    # admin interface (which is not e-mailed) and then follow the recovery
    # flow in the public facing pages of kratos

    try:
        # Get the ID of the user
        kratos_user = KratosUser.find_by_email(KRATOS_ADMIN, email)
        if kratos_user is None:
            current_app.logger.error(f"User with email '{email}' not found")
            return False


        # Get a recovery URL
        url = kratos_user.get_recovery_link()

        # Execute UI sequence to set password, given we have a recovery URL
        result = kratos_user.ui_set_password(KRATOS_PUBLIC_URL, url, password)

    except Exception as error:
        current_app.logger.error(f"Error while setting password: {error}")
        return False

    if result:
        current_app.logger.info("Success setting password")
    else:
        current_app.logger.error("Failed to set password. Password too weak?")

    return result



@user_cli.command('list')
def list_user():
    """Show a list of users in the database"""
    current_app.logger.info("Listing users")
    users = KratosUser.find_all(KRATOS_ADMIN)

    for obj in users:
        print(obj)


@user_cli.command('recover')
@click.argument('email')
def recover_user(email):
    """Get recovery link for a user, to manual update the user/use
    :param email: Email address of the user
    """

    current_app.logger.info(f"Trying to send recover email for user: {email}")

    try:
        # Get the ID of the user
        kratos_user = KratosUser.find_by_email(KRATOS_ADMIN, email)

        # Get a recovery URL
        url = kratos_user.get_recovery_link()

        print(url)
    except BackendError as error:
        current_app.logger.error(f"Error while getting reset link: {error}")




cli.cli.add_command(user_cli)