import os
import shutil
import pytest
from tests.testutils import cli, create_artifact_share
from tests.testutils.site import IS_LINUX

from buildstream import _yaml


DATA_DIR = os.path.join(
    os.path.dirname(os.path.realpath(__file__)),
    "junctions",
)


# Assert that a given artifact is in the share
#
def assert_shared(cli, share, project_name, project, element_name):
    # NOTE: 'test' here is the name of the project
    # specified in the project.conf we are testing with.
    #
    cache_key = cli.get_element_key(project, element_name)
    if not share.has_artifact(project_name, element_name, cache_key):
        raise AssertionError("Artifact share at {} does not contain the expected element {}"
                             .format(share.repo, element_name))


def project_set_artifacts(project, url):
    project_conf_file = os.path.join(project, 'project.conf')
    project_config = _yaml.load(project_conf_file)
    project_config.update({
        'artifacts': {
            'url': url,
            'push': True
        }
    })
    _yaml.dump(_yaml.node_sanitize(project_config), filename=project_conf_file)


@pytest.mark.skipif(not IS_LINUX, reason='Only available on linux')
@pytest.mark.datafiles(DATA_DIR)
def test_push_pull(cli, tmpdir, datafiles):
    project = os.path.join(str(datafiles), 'foo')
    base_project = os.path.join(str(project), 'base')

    share = create_artifact_share(os.path.join(str(tmpdir), 'artifactshare-foo'))
    base_share = create_artifact_share(os.path.join(str(tmpdir), 'artifactshare-base'))

    # First build it without the artifact cache configured
    result = cli.run(project=project, args=['build', 'target.bst'])
    assert result.exit_code == 0

    # Assert that we are now cached locally
    state = cli.get_element_state(project, 'target.bst')
    assert state == 'cached'
    state = cli.get_element_state(base_project, 'target.bst')
    assert state == 'cached'

    project_set_artifacts(project, share.repo)
    project_set_artifacts(base_project, base_share.repo)

    # Now try bst push
    result = cli.run(project=project, args=['push', '--deps', 'all', 'target.bst'])
    assert result.exit_code == 0

    # And finally assert that the artifacts are in the right shares
    assert_shared(cli, share, 'foo', project, 'target.bst')
    assert_shared(cli, base_share, 'base', base_project, 'target.bst')

    # Make sure we update the summary in our artifact shares,
    # we dont have a real server around to do it
    #
    share.update_summary()
    base_share.update_summary()

    # Now we've pushed, delete the user's local artifact cache
    # directory and try to redownload it from the share
    #
    artifacts = os.path.join(cli.directory, 'artifacts')
    shutil.rmtree(artifacts)

    # Assert that we are now in a downloadable state, nothing
    # is cached locally anymore
    state = cli.get_element_state(project, 'target.bst')
    assert state == 'downloadable'
    state = cli.get_element_state(base_project, 'target.bst')
    assert state == 'downloadable'

    # Now try bst pull
    result = cli.run(project=project, args=['pull', '--deps', 'all', 'target.bst'])
    assert result.exit_code == 0

    # And assert that they are again in the local cache, without having built
    state = cli.get_element_state(project, 'target.bst')
    assert state == 'cached'
    state = cli.get_element_state(base_project, 'target.bst')
    assert state == 'cached'