import contextlib
import functools
import itertools
import os
import subprocess
import time
import unittest

from varlink import VarlinkError

MethodNotImplemented = 'org.varlink.service.MethodNotImplemented'


class PodmanTestCase(unittest.TestCase):
    """Hide the sausage making of initializing storage."""

    @classmethod
    def setUpClass(cls):
        if hasattr(PodmanTestCase, 'alpine_process'):
            PodmanTestCase.tearDownClass()

        def run_cmd(*args):
            cmd = list(itertools.chain(*args))
            try:
                pid = subprocess.Popen(
                    cmd,
                    close_fds=True,
                    stdout=subprocess.PIPE,
                    stderr=subprocess.PIPE)
                out, err = pid.communicate()
            except OSError as e:
                print('{}: {}({})'.format(cmd, e.strerror, e.returncode))
            except ValueError as e:
                print('{}: {}'.format(cmd, e.message))
                raise
            else:
                return out.strip()

        tmpdir = os.environ.get('TMPDIR', '/tmp')
        podman_args = [
            '--storage-driver=vfs',
            '--cgroup-manager=cgroupfs',
            '--root={}/crio'.format(tmpdir),
            '--runroot={}/crio-run'.format(tmpdir),
            '--cni-config-dir={}/cni/net.d'.format(tmpdir),
        ]

        run_podman = functools.partial(run_cmd, ['podman'], podman_args)

        id = run_podman(['pull', 'alpine'])
        setattr(PodmanTestCase, 'alpine_id', id)

        run_podman(['pull', 'busybox'])
        run_podman(['images'])

        run_cmd(['rm', '-f', '{}/alpine_gold.tar'.format(tmpdir)])
        run_podman([
            'save', '--output', '{}/alpine_gold.tar'.format(tmpdir), 'alpine'
        ])

        PodmanTestCase.alpine_log = open(
            os.path.join('/tmp/', 'alpine.log'), 'w')

        cmd = ['podman']
        cmd.extend(podman_args)
        # cmd.extend(['run', '-d', 'alpine', 'sleep', '500'])
        cmd.extend(['run', '-dt', 'alpine', '/bin/sh'])
        PodmanTestCase.alpine_process = subprocess.Popen(
            cmd,
            stdout=PodmanTestCase.alpine_log,
            stderr=subprocess.STDOUT,
        )

        PodmanTestCase.busybox_log = open(
            os.path.join('/tmp/', 'busybox.log'), 'w')

        cmd = ['podman']
        cmd.extend(podman_args)
        cmd.extend(['create', 'busybox'])
        PodmanTestCase.busybox_process = subprocess.Popen(
            cmd,
            stdout=PodmanTestCase.busybox_log,
            stderr=subprocess.STDOUT,
        )
        # give podman time to start ctnr
        time.sleep(2)

        # Close our handle of file
        PodmanTestCase.alpine_log.close()
        PodmanTestCase.busybox_log.close()

    @classmethod
    def tearDownClass(cls):
        try:
            PodmanTestCase.alpine_process.kill()
            assert 0 == PodmanTestCase.alpine_process.wait(500)
            delattr(PodmanTestCase, 'alpine_process')

            PodmanTestCase.busybox_process.kill()
            assert 0 == PodmanTestCase.busybox_process.wait(500)
        except Exception as e:
            print('Exception: {}'.format(e))
            raise

    @contextlib.contextmanager
    def assertRaisesNotImplemented(self):
        with self.assertRaisesRegex(VarlinkError, MethodNotImplemented):
            yield