from cStringIO import StringIO

import contextlib
import logging
import time

from teuthology import misc as teuthology
from teuthology import contextutil
from teuthology.parallel import parallel
from ..orchestra import run

log = logging.getLogger(__name__)


def _update_deb_package_list_and_install(ctx, remote, debs, config):
    """
    updates the package list so that apt-get can
    download the appropriate packages
    """

    # check for ceph release key
    r = remote.run(
        args=[
            'sudo', 'apt-key', 'list', run.Raw('|'), 'grep', 'Ceph',
            ],
        stdout=StringIO(),
        )
    if r.stdout.getvalue().find('Ceph automated package') == -1:
        # if it doesn't exist, add it
        remote.run(
                args=[
                    'wget', '-q', '-O-',
                    'https://ceph.com/git/?p=ceph.git;a=blob_plain;f=keys/autobuild.asc',
                    run.Raw('|'),
                    'sudo', 'apt-key', 'add', '-',
                    ],
                stdout=StringIO(),
                )

    # get distro name and arch
    r = remote.run(
            args=['lsb_release', '-sc'],
            stdout=StringIO(),
            )
    dist = r.stdout.getvalue().strip()
    r = remote.run(
            args=['arch'],
            stdout=StringIO(),
            )
    arch = r.stdout.getvalue().strip()
    log.info("dist %s arch %s", dist, arch)

    # branch/tag/sha1 flavor
    flavor = config.get('flavor', 'basic')

    uri = None
    log.info('config is %s', config)
    if config.get('sha1') is not None:
        uri = 'sha1/' + config.get('sha1')
    elif config.get('tag') is not None:
        uri = 'ref/' + config.get('tag')
    elif config.get('branch') is not None:
        uri = 'ref/' + config.get('branch')
    else:
        uri = 'ref/master'

    base_url = 'http://{host}/ceph-deb-{dist}-{arch}-{flavor}/{uri}'.format(
        host=ctx.teuthology_config.get('gitbuilder_host',
                                       'gitbuilder.ceph.com'),
        dist=dist,
        arch=arch,
        flavor=flavor,
        uri=uri,
        )
    log.info('Pulling from %s', base_url)

    # get package version string
    while True:
        r = remote.run(
            args=[
                'wget', '-q', '-O-', base_url + '/version',
                ],
            stdout=StringIO(),
            check_status=False,
            )
        if r.exitstatus != 0:
            if config.get('wait_for_package'):
                log.info('Package not there yet, waiting...')
                time.sleep(15)
                continue
            raise Exception('failed to fetch package version from %s' %
                            base_url + '/version')
        version = r.stdout.getvalue().strip()
        log.info('Package version is %s', version)
        break

    remote.run(
        args=[
            'echo', 'deb', base_url, dist, 'main',
            run.Raw('|'),
            'sudo', 'tee', '/etc/apt/sources.list.d/ceph.list'
            ],
        stdout=StringIO(),
        )
    remote.run(
        args=[
            'sudo', 'apt-get', 'update', run.Raw('&&'),
            'sudo', 'apt-get', '-y', '--force-yes',
            'install',
            ] + ['%s=%s' % (d, version) for d in debs],
        stdout=StringIO(),
        )


def install_debs(ctx, debs, config):
    """
    installs Debian packages.
    """
    log.info("Installing ceph debian packages: {debs}".format(
            debs=', '.join(debs)))
    with parallel() as p:
        for remote in ctx.cluster.remotes.iterkeys():
            p.spawn(
                _update_deb_package_list_and_install,
                ctx, remote, debs, config)

def _remove_deb(remote, debs):
    # first ask nicely
    remote.run(
        args=[
            'for', 'd', 'in',
            ] + debs + [
            run.Raw(';'),
            'do',
            'sudo', 'apt-get', '-y', '--force-yes', 'purge',
            run.Raw('$d'),
            run.Raw('||'),
            'true',
            run.Raw(';'),
            'done',
            ])
    # mop up anything that is broken
    remote.run(
        args=[
            'dpkg', '-l',
            run.Raw('|'),
            'grep', '^.HR',
            run.Raw('|'),
            'awk', '{print $2}',
            run.Raw('|'),
            'sudo',
            'xargs', '--no-run-if-empty',
            'dpkg', '-P', '--force-remove-reinstreq',
            ])
    # then let apt clean up
    remote.run(
        args=[
            'sudo', 'apt-get', '-y', '--force-yes',
            'autoremove',
            ],
        stdout=StringIO(),
        )

def remove_debs(ctx, debs):
    log.info("Removing/purging debian packages {debs}".format(
            debs=', '.join(debs)))
    with parallel() as p:
        for remote in ctx.cluster.remotes.iterkeys():
            p.spawn(_remove_deb, remote, debs)

def _remove_sources_list(remote):
    remote.run(
        args=[
            'sudo', 'rm', '-f', '/etc/apt/sources.list.d/ceph.list',
            run.Raw('&&'),
            'sudo', 'apt-get', 'update',
            # ignore failure
            run.Raw('||'),
            'true',
            ],
        stdout=StringIO(),
       )

def remove_sources(ctx):
    log.info("Removing ceph sources list from apt")
    with parallel() as p:
        for remote in ctx.cluster.remotes.iterkeys():
            p.spawn(_remove_sources_list, remote)


@contextlib.contextmanager
def install(ctx, config):
    debs = [
        'ceph',
        'ceph-dbg',
        'ceph-mds',
        'ceph-mds-dbg',
        'ceph-common',
        'ceph-common-dbg',
        'ceph-fuse',
        'ceph-fuse-dbg',
        'ceph-test',
        'ceph-test-dbg',
        'radosgw',
        'radosgw-dbg',
        'python-ceph',
        'libcephfs1',
        'libcephfs1-dbg',
        'libcephfs-java',
        ]

    # pull any additional packages out of config
    extra_debs = config.get('extra_packages')
    log.info('extra packages: {packages}'.format(packages=extra_debs))
    debs = debs + extra_debs

    # install lib deps (so we explicitly specify version), but do not
    # uninstall them, as other packages depend on them (e.g., kvm)
    debs_install = debs + [
        'librados2',
        'librados2-dbg',
        'librbd1',
        'librbd1-dbg',
        ]
    install_debs(ctx, debs_install, config)
    try:
        yield
    finally:
        remove_debs(ctx, debs)
        remove_sources(ctx)


@contextlib.contextmanager
def task(ctx, config):
    """
    Install ceph packages
    """
    if config is None:
        config = {}
    assert isinstance(config, dict), \
        "task ceph only supports a dictionary for configuration"

    overrides = ctx.config.get('overrides', {})
    teuthology.deep_merge(config, overrides.get('ceph', {}))

    # Flavor tells us what gitbuilder to fetch the prebuilt software
    # from. It's a combination of possible keywords, in a specific
    # order, joined by dashes. It is used as a URL path name. If a
    # match is not found, the teuthology run fails. This is ugly,
    # and should be cleaned up at some point.

    flavor = config.get('flavor', 'basic')

    if config.get('path'):
        # local dir precludes any other flavors
        flavor = 'local'
    else:
        if config.get('valgrind'):
            log.info('Using notcmalloc flavor and running some daemons under valgrind')
            flavor = 'notcmalloc'
        else:
            if config.get('coverage'):
                log.info('Recording coverage for this run.')
                flavor = 'gcov'

    ctx.summary['flavor'] = flavor
    
    with contextutil.nested(
        lambda: install(ctx=ctx, config=dict(
                branch=config.get('branch'),
                tag=config.get('tag'),
                sha1=config.get('sha1'),
                flavor=flavor,
                extra_packages=config.get('extra_packages', []),
                wait_for_package=ctx.config.get('wait-for-package', False),
                )),
        ):
        yield