import base64
import os
import random
import string
import tempfile
from typing import Tuple, Any, Generator

import pytest
from flask import Flask
from flask.testing import FlaskClient, FlaskCliRunner
from werkzeug.test import Client

from server import create_app, register_blueprints, register_error_handlers
from server.db import init_db
from server.model import User
from server.service import user_service


def add_test_user() -> Tuple[str, str]:
    test_username = 'test_' + ''.join(
        random.choices(string.ascii_letters + string.digits, k=17)).strip()
    test_password = ''.join(
        random.choices(string.ascii_letters + string.digits, k=32)).strip()
    user_service.register(test_username, test_password, User.ROLE_ADMIN, False)
    return test_username, test_password


@pytest.fixture
def app() -> Generator[Flask, Any, Any]:
    """Create and configure a new server_app instance for each test."""
    # create a temporary file to isolate the database for each test
    db_fd, db_path = tempfile.mkstemp(suffix='.db')
    test_database_uri = 'sqlite:///{}'.format(db_path)
    # create the server_app with common test config
    server_app = create_app({
        'TESTING': True,
        'SQLALCHEMY_DATABASE_URI': test_database_uri,
    })
    register_blueprints(server_app)
    register_error_handlers(server_app)

    # create the database and load test data
    with server_app.app_context():
        init_db()
        test_username, test_password = add_test_user()
        server_app.config['test_username'] = test_username
        server_app.config['test_password'] = test_password
        # get_db().executescript(_data_sql)

    yield server_app

    # close and remove the temporary database
    os.close(db_fd)
    os.unlink(db_path)


@pytest.fixture
def client(app: Flask) -> FlaskClient:
    """A test client for the app."""
    return app.test_client()


@pytest.fixture
def runner(app: Flask) -> FlaskCliRunner:
    """A test runner for the app's Click commands."""
    return app.test_cli_runner()


class AuthActions(object):
    def __init__(self,
                 client: Client,
                 username: str = "",
                 password: str = "") -> None:
        self._client = client
        self.username: str = username
        self.password: str = password
        self.token: str = ""

    def configure(self, username: str, password: str) -> Any:
        self.username = username
        self.password = password
        return self

    def login(self) -> Any:
        auth_header = self.get_authorization_header_basic()
        result = self._client.post(
            '/auth/login',
            headers={
                auth_header[0]: auth_header[1]
            }
        )
        self.token = result.json['token']
        return result

    def bump(self) -> Any:
        auth_header = self.get_authorization_header_token()
        return self._client.post(
            '/auth/bump',
            headers={
                auth_header[0]: auth_header[1]
            }
        )

    def logout(self) -> Any:
        auth_header = self.get_authorization_header_token()
        return self._client.post(
            '/auth/logout',
            headers={
                auth_header[0]: auth_header[1]
            }
        )

    def get_authorization_header_basic(self) -> Tuple[str, str]:
        credentials = base64.b64encode(
            '{}:{}'.format(self.username, self.password).encode('utf8')) \
            .decode('utf8').strip()
        return 'Authorization', 'Basic {}'.format(credentials)

    def get_authorization_header_token(self) -> Tuple[str, str]:
        credentials = base64.b64encode(
            '{}:{}'.format(self.username, self.token).encode('utf8')) \
            .decode('utf8').strip()
        return 'X-Auth-Token', '{}'.format(credentials)

    def __enter__(self) -> 'AuthActions':
        return self.login()

    def __exit__(self, type: Any, value: Any, traceback: Any) -> None:
        self.logout()


@pytest.fixture
def auth(client: Client) -> AuthActions:
    return AuthActions(client,
                       client.application.config.get('test_username'),
                       client.application.config.get('test_password'))