import pytest
from bs4 import BeautifulSoup

from sanic import Sanic
from sanic.response import text
from sanic.exceptions import InvalidUsage, ServerError, NotFound, Unauthorized
from sanic.exceptions import Forbidden, abort


class SanicExceptionTestException(Exception):
    pass


@pytest.fixture(scope='module')
def exception_app():
    app = Sanic('test_exceptions')

    @app.route('/')
    def handler(request):
        return text('OK')

    @app.route('/error')
    def handler_error(request):
        raise ServerError("OK")

    @app.route('/404')
    def handler_404(request):
        raise NotFound("OK")

    @app.route('/403')
    def handler_403(request):
        raise Forbidden("Forbidden")

    @app.route('/401')
    def handler_401(request):
        raise Unauthorized("Unauthorized")

    @app.route('/401/basic')
    def handler_401_basic(request):
        raise Unauthorized("Unauthorized", scheme="Basic", realm="Sanic")

    @app.route('/401/digest')
    def handler_401_digest(request):
        raise Unauthorized("Unauthorized",
                           scheme="Digest",
                           realm="Sanic",
                           qop="auth, auth-int",
                           algorithm="MD5",
                           nonce="abcdef",
                           opaque="zyxwvu")

    @app.route('/401/bearer')
    def handler_401_bearer(request):
        raise Unauthorized("Unauthorized", scheme="Bearer")

    @app.route('/invalid')
    def handler_invalid(request):
        raise InvalidUsage("OK")

    @app.route('/abort/401')
    def handler_401_error(request):
        abort(401)

    @app.route('/abort')
    def handler_500_error(request):
        abort(500)
        return text("OK")

    @app.route('/divide_by_zero')
    def handle_unhandled_exception(request):
        1 / 0

    @app.route('/error_in_error_handler_handler')
    def custom_error_handler(request):
        raise SanicExceptionTestException('Dummy message!')

    @app.exception(SanicExceptionTestException)
    def error_in_error_handler_handler(request, exception):
        1 / 0

    return app


def test_catch_exception_list():
    app = Sanic('exception_list')

    @app.exception([SanicExceptionTestException, NotFound])
    def exception_list(request, exception):
        return text("ok")

    @app.route('/')
    def exception(request):
        raise SanicExceptionTestException("You won't see me")

    request, response = app.test_client.get('/random')
    assert response.text == 'ok'

    request, response = app.test_client.get('/')
    assert response.text == 'ok'


def test_no_exception(exception_app):
    """Test that a route works without an exception"""
    request, response = exception_app.test_client.get('/')
    assert response.status == 200
    assert response.text == 'OK'


def test_server_error_exception(exception_app):
    """Test the built-in ServerError exception works"""
    request, response = exception_app.test_client.get('/error')
    assert response.status == 500


def test_invalid_usage_exception(exception_app):
    """Test the built-in InvalidUsage exception works"""
    request, response = exception_app.test_client.get('/invalid')
    assert response.status == 400


def test_not_found_exception(exception_app):
    """Test the built-in NotFound exception works"""
    request, response = exception_app.test_client.get('/404')
    assert response.status == 404


def test_forbidden_exception(exception_app):
    """Test the built-in Forbidden exception"""
    request, response = exception_app.test_client.get('/403')
    assert response.status == 403


def test_unauthorized_exception(exception_app):
    """Test the built-in Unauthorized exception"""
    request, response = exception_app.test_client.get('/401')
    assert response.status == 401

    request, response = exception_app.test_client.get('/401/basic')
    assert response.status == 401
    assert response.headers.get('WWW-Authenticate') is not None
    assert response.headers.get('WWW-Authenticate') == "Basic realm='Sanic'"

    request, response = exception_app.test_client.get('/401/digest')
    assert response.status == 401

    auth_header = response.headers.get('WWW-Authenticate')
    assert auth_header is not None
    assert auth_header.startswith('Digest')
    assert "qop='auth, auth-int'" in auth_header
    assert "algorithm='MD5'" in auth_header
    assert "nonce='abcdef'" in auth_header
    assert "opaque='zyxwvu'" in auth_header

    request, response = exception_app.test_client.get('/401/bearer')
    assert response.status == 401
    assert response.headers.get('WWW-Authenticate') == "Bearer"


def test_handled_unhandled_exception(exception_app):
    """Test that an exception not built into sanic is handled"""
    request, response = exception_app.test_client.get('/divide_by_zero')
    assert response.status == 500
    soup = BeautifulSoup(response.body, 'html.parser')
    assert soup.h1.text == 'Internal Server Error'

    message = " ".join(soup.p.text.split())
    assert message == (
        "The server encountered an internal error and "
        "cannot complete your request.")


def test_exception_in_exception_handler(exception_app):
    """Test that an exception thrown in an error handler is handled"""
    request, response = exception_app.test_client.get(
        '/error_in_error_handler_handler')
    assert response.status == 500
    assert response.body == b'An error occurred while handling an error'


def test_exception_in_exception_handler_debug_off(exception_app):
    """Test that an exception thrown in an error handler is handled"""
    request, response = exception_app.test_client.get(
        '/error_in_error_handler_handler',
        debug=False)
    assert response.status == 500
    assert response.body == b'An error occurred while handling an error'


def test_exception_in_exception_handler_debug_on(exception_app):
    """Test that an exception thrown in an error handler is handled"""
    request, response = exception_app.test_client.get(
        '/error_in_error_handler_handler',
        debug=True)
    assert response.status == 500
    assert response.body.startswith(b'Exception raised in exception ')


def test_abort(exception_app):
    """Test the abort function"""
    request, response = exception_app.test_client.get('/abort/401')
    assert response.status == 401

    request, response = exception_app.test_client.get('/abort')
    assert response.status == 500