# SPDX-License-Identifier: GPL-3.0-or-later

"""
Common fixtures for Haketilo unit tests
"""

# This file is part of Haketilo.
#
# Copyright (C) 2021 Wojtek Kosior <koszko@koszko.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.
#
# I, Wojtek Kosior, thereby promise not to sue for violation of this file's
# license. Although I request that you do not make use of this code in a
# proprietary program, I am not going to enforce this in court.

import pytest
from pathlib import Path
from tempfile import TemporaryDirectory
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

from .profiles           import firefox_safe_mode
from .server             import do_an_internet
from .extension_crafting import make_extension
from .world_wide_library import start_serving_script, dump_scripts
from .misc_constants     import proj_root

@pytest.fixture(scope="session")
def proxy():
    httpd = do_an_internet()
    yield httpd
    httpd.shutdown()

@pytest.fixture(scope="session")
def _driver(proxy):
    with firefox_safe_mode(proxy.server_port) as driver:
        yield driver
        driver.quit()

def close_all_but_one_window(driver):
    while len(driver.window_handles) > 1:
        driver.switch_to.window(driver.window_handles[-1])
        driver.close()
    driver.switch_to.window(driver.window_handles[0])

@pytest.fixture()
def driver(proxy, _driver, request):
    nav_target = request.node.get_closest_marker('get_page')
    nav_target = nav_target.args[0] if nav_target else 'about:blank'

    second_driver = request.node.get_closest_marker('second_driver')

    if second_driver:
        with firefox_safe_mode(proxy.server_port) as _driver:
            _driver.get(nav_target)
            yield _driver
            _driver.quit()
    else:
        close_all_but_one_window(_driver)
        _driver.get(nav_target)
        _driver.implicitly_wait(0)
        yield _driver

def safe_uninstall_addon(driver, addon_id):
    """
    Unloading an extension might cause its windows to vanish. Make sure there's
    at least one window navigated to some other page before uninstalling the
    addon. Otherwise, we could be left with a windowless browser :c
    """
    driver.switch_to.window(driver.window_handles[-1])
    driver.get('https://gotmyowndoma.in/')
    driver.uninstall_addon(addon_id)

@pytest.fixture()
def webextension(driver, request):
    ext_data = request.node.get_closest_marker('ext_data')
    if ext_data is None:
        raise Exception('"webextension" fixture requires "ext_data" marker to be set')
    ext_data = ext_data.args[0].copy()

    navigate_to = ext_data.get('navigate_to')
    if navigate_to is not None:
        del ext_data['navigate_to']

    driver.get('https://gotmyowndoma.in/')
    ext_path = make_extension(Path(driver.firefox_profile.path), **ext_data)
    addon_id = driver.install_addon(str(ext_path), temporary=True)
    get_url = lambda d: d.execute_script('return window.ext_page_url;')
    ext_page_url = WebDriverWait(driver, 10).until(get_url)
    driver.get(ext_page_url)

    if navigate_to is not None:
        driver.get(driver.current_url.replace('testpage.html', navigate_to))

    yield

    safe_uninstall_addon(driver, addon_id)
    ext_path.unlink()

@pytest.fixture()
def haketilo(driver):
    addon_id = driver.install_addon(str(Path.cwd() / 'mozilla-build.zip'),
                                    temporary=True)

    yield

    safe_uninstall_addon(driver, addon_id)

script_injector_script = '''\
/*
 * Selenium by default executes scripts in some weird one-time context. We want
 * separately-loaded scripts to be able to access global variables defined
 * before, including those declared with `const` or `let`. To achieve that, we
 * run our scripts by injecting them into the page with a <script> tag that runs
 * javascript served by our proxy. We use custom properties of the `window`
 * object to communicate with injected code.
 */
const inject = async () => {
    delete window.haketilo_selenium_return_value;
    delete window.haketilo_selenium_exception;
    window.returnval = val => window.haketilo_selenium_return_value = val;

    const injectee = document.createElement('script');
    injectee.src = arguments[0];
    injectee.type = "application/javascript";
    injectee.async = true;
    const prom = new Promise(cb => injectee.onload = cb);

    window.arguments = arguments[1];
    document.body.append(injectee);

    await prom;

    /*
     * To ease debugging, we want this script to signal all exceptions from the
     * injectee.
     */
    if (window.haketilo_selenium_exception !== false)
        throw ['haketilo_selenium_error',
               'Error in injected script! Check your geckodriver.log and ./injected_scripts/!'];

    return window.haketilo_selenium_return_value;
}
return inject();
'''

def _execute_in_page_context(driver, script, args):
    script = script + '\n;\nwindow.haketilo_selenium_exception = false;'
    script_url = start_serving_script(script)

    try:
        result = driver.execute_script(script_injector_script, script_url, args)
        if type(result) is list and len(result) == 2 and \
           result[0] == 'haketilo_selenium_error':
            raise Exception(result[1])
        return result
    except Exception as e:
        dump_scripts()
        raise e from None

# Some fixtures here just define functions that operate on driver. We should
# consider making them into webdriver wrapper class methods.

@pytest.fixture()
def execute_in_page(driver):
    def do_execute(script, *args):
        return _execute_in_page_context(driver, script, args)

    yield do_execute

@pytest.fixture()
def wait_elem_text(driver):
    def do_wait(id, text):
        WebDriverWait(driver, 10).until(
            EC.text_to_be_present_in_element((By.ID, id), text)
        )

    yield do_wait