import datetime
import django
import os
import shutil
import sys
from django.conf import settings
from django.test.utils import get_runner
from tempfile import mkdtemp


class DjangoEnvironment(object):
    def __init__(self, path=None, base_path=None, remove_after=True,
                 enable_modules=None):
        self.path = path
        if base_path is not None:
            self._base_path = base_path
        else:
            self._base_path = os.getcwd()
        self._remove_after = remove_after
        self._original_sys_path = None
        self._modified_sys_path = None
        if enable_modules is not None:
            self._enable_modules = enable_modules
        else:
            self._enable_modules = []

    def admin_cmd(self, *args):
        cmd = 'django-dav-admin'
        for arg in args:
            cmd += ' "{}"'.format(arg)
        os.system(cmd)

    def __enter__(self):
        if self.path is None:
            prefix = 'testrun-{datetime}-'.format(
                datetime=datetime.datetime.now().strftime('%Y%m%d-%H%M')
            )
            self.path = mkdtemp(prefix=prefix, dir=self._base_path)

        self.admin_cmd('setup', self.path)
        for mod in self._enable_modules:
            self.admin_cmd('enable_module', self.path, mod)

        self._original_sys_path = sys.path
        sys.path.append(self.path)
        self._modified_sys_path = sys.path

        os.environ['DJANGO_SETTINGS_MODULE'] = 'main.settings'
        django.setup()

        return self

    def __exit__(self, *args):
        if self._modified_sys_path is not None and self._original_sys_path is not None:
            if sys.path == self._modified_sys_path:
                sys.path = self._original_sys_path
        if self._remove_after:
            shutil.rmtree(self.path)


class TestSuite(object):
    def __call__(self):
        modules = ['dav_auth']
        tests = ['dav_base'] + modules
        test_tags = None
        exclude_test_tags = ['browser']
        failures = 0

        with DjangoEnvironment(enable_modules=modules):
            test_runner_class = get_runner(settings)
            test_runner = test_runner_class(tags=test_tags, exclude_tags=exclude_test_tags)
            failures = test_runner.run_tests(tests)

        sys.exit(bool(failures))