import fcntl
import os
import platform
import re
import shutil
import signal
import socket
import stat
import subprocess
import sys
import tempfile
import time
from multiprocessing import Process

import pytest

from unit.check.go import check_go
from unit.check.node import check_node
from unit.check.tls import check_openssl
from unit.check.isolation import check_isolation
from unit.option import option
from unit.utils import public_dir
from unit.utils import waitforfiles


def pytest_addoption(parser):
    parser.addoption(
        "--detailed",
        default=False,
        action="store_true",
        help="Detailed output for tests",
    )
    parser.addoption(
        "--print-log",
        default=False,
        action="store_true",
        help="Print unit.log to stdout in case of errors",
    )
    parser.addoption(
        "--save-log",
        default=False,
        action="store_true",
        help="Save unit.log after the test execution",
    )
    parser.addoption(
        "--unsafe",
        default=False,
        action="store_true",
        help="Run unsafe tests",
    )


unit_instance = {}
_processes = []

def pytest_configure(config):
    option.config = config.option

    option.detailed = config.option.detailed
    option.print_log = config.option.print_log
    option.save_log = config.option.save_log
    option.unsafe = config.option.unsafe

    option.generated_tests = {}
    option.current_dir = os.path.abspath(
        os.path.join(os.path.dirname(__file__), os.pardir)
    )
    option.test_dir = option.current_dir + '/test'
    option.architecture = platform.architecture()[0]
    option.system = platform.system()

    option.cache_dir = tempfile.mkdtemp(prefix='unit-test-cache-')
    public_dir(option.cache_dir)

    # set stdout to non-blocking

    if option.detailed or option.print_log:
        fcntl.fcntl(sys.stdout.fileno(), fcntl.F_SETFL, 0)


def pytest_generate_tests(metafunc):
    cls = metafunc.cls
    if (not hasattr(cls, 'application_type')
            or cls.application_type == None
            or cls.application_type == 'external'):
        return

    type = cls.application_type

    def generate_tests(versions):
        metafunc.fixturenames.append('tmp_ct')
        metafunc.parametrize('tmp_ct', versions)

        for version in versions:
            option.generated_tests[
                metafunc.function.__name__ + '[{}]'.format(version)
            ] = (type + ' ' + version)

    # take available module from option and generate tests for each version

    for module, prereq_version in cls.prerequisites['modules'].items():
        if module in option.available['modules']:
            available_versions = option.available['modules'][module]

            if prereq_version == 'all':
                generate_tests(available_versions)

            elif prereq_version == 'any':
                option.generated_tests[metafunc.function.__name__] = (
                    type + ' ' + available_versions[0]
                )
            elif callable(prereq_version):
                generate_tests(
                    list(filter(prereq_version, available_versions))
                )

            else:
                raise ValueError(
                    """
Unexpected prerequisite version "%s" for module "%s" in %s.
'all', 'any' or callable expected."""
                    % (str(prereq_version), module, str(cls))
                )


def pytest_sessionstart(session):
    option.available = {'modules': {}, 'features': {}}

    unit = unit_run()
    option.temp_dir = unit['temp_dir']

    # read unit.log

    for i in range(50):
        with open(unit['temp_dir'] + '/unit.log', 'r') as f:
            log = f.read()
            m = re.search('controller started', log)

            if m is None:
                time.sleep(0.1)
            else:
                break

    if m is None:
        _print_log(log)
        exit("Unit is writing log too long")

    # discover available modules from unit.log

    for module in re.findall(r'module: ([a-zA-Z]+) (.*) ".*"$', log, re.M):
        versions = option.available['modules'].setdefault(module[0], [])
        if module[1] not in versions:
            versions.append(module[1])

    # discover modules from check

    option.available['modules']['openssl'] = check_openssl(unit['unitd'])
    option.available['modules']['go'] = check_go(
        option.current_dir, unit['temp_dir'], option.test_dir
    )
    option.available['modules']['node'] = check_node(option.current_dir)

    # remove None values

    option.available['modules'] = {
        k: v for k, v in option.available['modules'].items() if v is not None
    }

    check_isolation()

    unit_stop()

    _check_alerts()

    shutil.rmtree(unit_instance['temp_dir'])


@pytest.hookimpl(tryfirst=True, hookwrapper=True)
def pytest_runtest_makereport(item, call):
    # execute all other hooks to obtain the report object
    outcome = yield
    rep = outcome.get_result()

    # set a report attribute for each phase of a call, which can
    # be "setup", "call", "teardown"

    setattr(item, "rep_" + rep.when, rep)


@pytest.fixture(scope='class', autouse=True)
def check_prerequisites(request):
    cls = request.cls
    missed = []

    # check modules

    if 'modules' in cls.prerequisites:
        available_modules = list(option.available['modules'].keys())

        for module in cls.prerequisites['modules']:
            if module in available_modules:
                continue

            missed.append(module)

    if missed:
        pytest.skip('Unit has no ' + ', '.join(missed) + ' module(s)')

    # check features

    if 'features' in cls.prerequisites:
        available_features = list(option.available['features'].keys())

        for feature in cls.prerequisites['features']:
            if feature in available_features:
                continue

            missed.append(feature)

    if missed:
        pytest.skip(', '.join(missed) + ' feature(s) not supported')


@pytest.fixture(autouse=True)
def run(request):
    unit = unit_run()
    option.temp_dir = unit['temp_dir']

    option.skip_alerts = [
        r'read signalfd\(4\) failed',
        r'sendmsg.+failed',
        r'recvmsg.+failed',
    ]
    option.skip_sanitizer = False

    yield

    # stop unit

    error = unit_stop()

    if error:
        _print_log()

    assert error is None, 'stop unit'

    # stop all processes

    error = stop_processes()

    if error:
        _print_log()

    assert error is None, 'stop unit'

    # check unit.log for alerts

    _check_alerts()

    # print unit.log in case of error

    if hasattr(request.node, 'rep_call') and request.node.rep_call.failed:
        _print_log()

    # remove unit.log

    if not option.save_log:
        shutil.rmtree(unit['temp_dir'])

def unit_run():
    global unit_instance
    build_dir = option.current_dir + '/build'
    unitd = build_dir + '/unitd'

    if not os.path.isfile(unitd):
        exit('Could not find unit')

    temp_dir = tempfile.mkdtemp(prefix='unit-test-')
    public_dir(temp_dir)

    if oct(stat.S_IMODE(os.stat(build_dir).st_mode)) != '0o777':
        public_dir(build_dir)

    os.mkdir(temp_dir + '/state')

    with open(temp_dir + '/unit.log', 'w') as log:
        unit_instance['process'] = subprocess.Popen(
            [
                unitd,
                '--no-daemon',
                '--modules',
                build_dir,
                '--state',
                temp_dir + '/state',
                '--pid',
                temp_dir + '/unit.pid',
                '--log',
                temp_dir + '/unit.log',
                '--control',
                'unix:' + temp_dir + '/control.unit.sock',
                '--tmp',
                temp_dir,
            ],
            stderr=log,
        )

    if not waitforfiles(temp_dir + '/control.unit.sock'):
        _print_log()
        exit('Could not start unit')

    unit_instance['temp_dir'] = temp_dir
    unit_instance['log'] = temp_dir + '/unit.log'
    unit_instance['control_sock'] = temp_dir + '/control.unit.sock'
    unit_instance['unitd'] = unitd

    return unit_instance


def unit_stop():
    p = unit_instance['process']

    if p.poll() is not None:
        return

    p.send_signal(signal.SIGQUIT)

    try:
        retcode = p.wait(15)
        if retcode:
            return 'Child process terminated with code ' + str(retcode)

    except KeyboardInterrupt:
        p.kill()
        raise

    except:
        p.kill()
        return 'Could not terminate unit'



def _check_alerts(path=None):
    if path is None:
        path = unit_instance['log']

    with open(path, 'r', encoding='utf-8', errors='ignore') as f:
        log = f.read()

    found = False

    alerts = re.findall(r'.+\[alert\].+', log)

    if alerts:
        print('\nAll alerts/sanitizer errors found in log:')
        [print(alert) for alert in alerts]
        found = True

    if option.skip_alerts:
        for skip in option.skip_alerts:
            alerts = [al for al in alerts if re.search(skip, al) is None]

    if alerts:
        _print_log(log)
        assert not alerts, 'alert(s)'

    if not option.skip_sanitizer:
        sanitizer_errors = re.findall('.+Sanitizer.+', log)

        if sanitizer_errors:
            _print_log(log)
            assert not sanitizer_errors, 'sanitizer error(s)'

    if found:
        print('skipped.')


def _print_log(data=None):
    path = unit_instance['log']

    print('Path to unit.log:\n' + path + '\n')

    if option.print_log:
        os.set_blocking(sys.stdout.fileno(), True)
        sys.stdout.flush()

        if data is None:
            with open(path, 'r', encoding='utf-8', errors='ignore') as f:
                shutil.copyfileobj(f, sys.stdout)
        else:
            sys.stdout.write(data)


def run_process(target, *args):
    global _processes

    process = Process(target=target, args=args)
    process.start()

    _processes.append(process)

def stop_processes():
    if not _processes:
        return

    fail = False
    for process in _processes:
        if process.is_alive():
            process.terminate()
            process.join(timeout=15)

            if process.is_alive():
                fail = True

    if fail:
        return 'Fail to stop process(es)'


@pytest.fixture()
def skip_alert():
    def _skip(*alerts):
        option.skip_alerts.extend(alerts)

    return _skip


@pytest.fixture
def temp_dir(request):
    return unit_instance['temp_dir']

@pytest.fixture
def is_unsafe(request):
    return request.config.getoption("--unsafe")

@pytest.fixture
def is_su(request):
    return os.geteuid() == 0

def pytest_sessionfinish(session):
    unit_stop()
    shutil.rmtree(option.cache_dir)