import argparse
import json
import logging
import subprocess
import urllib
import yaml
import re
import collections
import tempfile
import os
import time

from teuthology import lockstatus as ls
from teuthology import misc as teuthology

log = logging.getLogger(__name__)

def lock_many(ctx, num, machinetype, user=None, description=None):
    if user is None:
        user = teuthology.get_user()
    success, content, status = ls.send_request('POST', ls._lock_url(ctx),
                                    urllib.urlencode(dict(
                user=user,
                num=num,
                machinetype=machinetype,
                desc=description,
                )))
    if success:
        machines = json.loads(content)
        log.debug('locked {machines}'.format(machines=', '.join(machines.keys())))
        return machines
    if status == 503:
        log.error('Insufficient nodes available to lock %d nodes.', num)
    else:
        log.error('Could not lock %d nodes, reason: unknown.', num)
    return []

def lock(ctx, name, user=None):
    if user is None:
        user = teuthology.get_user()
    success, _, _ = ls.send_request('POST', ls._lock_url(ctx) + '/' + name,
                              urllib.urlencode(dict(user=user)))
    if success:
        log.debug('locked %s as %s', name, user)
    else:
        log.error('failed to lock %s', name)
    return success

def unlock(ctx, name, user=None):
    if user is None:
        user = teuthology.get_user()
    success, _ , _ = ls.send_request('DELETE', ls._lock_url(ctx) + '/' + name + '?' + \
                                  urllib.urlencode(dict(user=user)))
    if success:
        log.debug('unlocked %s', name)
        if not destroy_if_vm(ctx, name):
            log.error('downburst destroy failed for %s',name)
    else:
        log.error('failed to unlock %s', name)
    return success

def list_locks(ctx):
    success, content, _ = ls.send_request('GET', ls._lock_url(ctx))
    if success:
        return json.loads(content)
    return None

def update_lock(ctx, name, description=None, status=None, sshpubkey=None):
    status_info = ls.get_status(ctx, name)
    phys_host = status_info['vpshost']
    if phys_host:
        keyscan_out = ''
        while not keyscan_out:
            time.sleep(10)
            keyscan_out, _ = keyscan_check(ctx, [name])
    updated = {}
    if description is not None:
        updated['desc'] = description
    if status is not None:
        updated['status'] = status
    if sshpubkey is not None:
        updated['sshpubkey'] = sshpubkey

    if updated:
        success, _, _ = ls.send_request('PUT', ls._lock_url(ctx) + '/' + name,
                                  body=urllib.urlencode(updated),
                                  headers={'Content-type': 'application/x-www-form-urlencoded'})
        return success
    return True

def _positive_int(string):
    value = int(string)
    if value < 1:
        raise argparse.ArgumentTypeError(
            '{string} is not positive'.format(string=string))
    return value

def canonicalize_hostname(s):
    if re.match('ubuntu@.*\.front\.sepia\.ceph\.com', s) is None:
        s = 'ubuntu@' + s + '.front.sepia.ceph.com'
    return s

def main():
    parser = argparse.ArgumentParser(description="""
Lock, unlock, or query lock status of machines.
""")
    parser.add_argument(
        '-v', '--verbose',
        action='store_true',
        default=False,
        help='be more verbose',
        )
    group = parser.add_mutually_exclusive_group(required=True)
    group.add_argument(
        '--list',
        action='store_true',
        default=False,
        help='Show lock info for machines owned by you, or only machines specified. Can be restricted by --owner, --status, and --locked.',
        )
    group.add_argument(
        '--list-targets',
        action='store_true',
        default=False,
        help='Show lock info for all machines, or only machines specified, in targets: yaml format. Can be restricted by --owner, --status, and --locked.',
        )
    group.add_argument(
        '--lock',
        action='store_true',
        default=False,
        help='lock particular machines',
        )
    group.add_argument(
        '--unlock',
        action='store_true',
        default=False,
        help='unlock particular machines',
        )
    group.add_argument(
        '--lock-many',
        dest='num_to_lock',
        type=_positive_int,
        help='lock this many machines',
        )
    group.add_argument(
        '--update',
        action='store_true',
        default=False,
        help='update the description or status of some machines',
        )
    group.add_argument(
        '--summary',
        action='store_true',
        default=False,
        help='summarize locked-machine counts by owner',
        )
    parser.add_argument(
        '-a', '--all',
        action='store_true',
        default=False,
        help='list all machines, not just those owned by you',
        )
    parser.add_argument(
        '--owner',
        default=None,
        help='owner of the lock(s) (must match to unlock a machine)',
        )
    parser.add_argument(
        '-f',
        action='store_true',
        default=False,
        help='don\'t exit after the first error, continue locking or unlocking other machines',
        )
    parser.add_argument(
        '--desc',
        default=None,
        help='lock description',
        )
    parser.add_argument(
        '--desc-pattern',
        default=None,
        help='lock description',
        )
    parser.add_argument(
        '--machine-type',
        default='plana',
        help='Type of machine to lock',
        )
    parser.add_argument(
        '--status',
        default=None,
        choices=['up', 'down'],
        help='whether a machine is usable for testing',
        )
    parser.add_argument(
        '--locked',
        default=None,
        choices=['true', 'false'],
        help='whether a machine is locked',
        )
    parser.add_argument(
        '--brief',
        action='store_true',
        default=False,
        help='Shorten information reported from --list',
        )
    parser.add_argument(
        '-t', '--targets',
        dest='targets',
        default=None,
        help='input yaml containing targets',
        )
    parser.add_argument(
        'machines',
        metavar='MACHINE',
        default=[],
        nargs='*',
        help='machines to operate on',
        )
    parser.add_argument(
        '--vm-type',
        default='ubuntu',
        help='virtual machine type',
        )

    ctx = parser.parse_args()

    loglevel = logging.ERROR
    if ctx.verbose:
        loglevel = logging.DEBUG

    logging.basicConfig(
        level=loglevel,
        )

    teuthology.read_config(ctx)

    ret = 0
    user = ctx.owner
    machines = [canonicalize_hostname(m) for m in ctx.machines]
    machines_to_update = []

    if ctx.targets:
        try:
            with file(ctx.targets) as f:
                g = yaml.safe_load_all(f)
                for new in g:
                    if 'targets' in new:
                        for t in new['targets'].iterkeys():
                            machines.append(t)
        except IOError, e:
            raise argparse.ArgumentTypeError(str(e))

    if ctx.f:
        assert ctx.lock or ctx.unlock, \
            '-f is only supported by --lock and --unlock'
    if machines:
        assert ctx.lock or ctx.unlock or ctx.list or ctx.list_targets \
            or ctx.update, \
            'machines cannot be specified with that operation'
    else:
        assert ctx.num_to_lock or ctx.list or ctx.list_targets or ctx.summary,\
            'machines must be specified for that operation'
    if ctx.all:
        assert ctx.list or ctx.list_targets, \
            '--all can only be used with --list and --list-targets'
        assert ctx.owner is None, \
            '--all and --owner are mutually exclusive'
        assert not machines, \
            '--all and listing specific machines are incompatible'

    if ctx.brief:
        assert ctx.list, '--brief only applies to --list'

    if ctx.list or ctx.list_targets:
        assert ctx.desc is None, '--desc does nothing with --list'

        if machines:
            statuses = [ls.get_status(ctx, machine) for machine in machines]
        else:
            statuses = list_locks(ctx)
        vmachines = []

        for vmachine in statuses:
            if vmachine['vpshost']:
                if vmachine['locked']:
                    vmachines.append(vmachine['name'])
        if vmachines:
            # Avoid ssh-keyscans for everybody when listing all machines
            # Listing specific machines will update the keys.
            if machines:
                scan_for_locks(ctx, vmachines)
                statuses = [ls.get_status(ctx, machine) for machine in machines]
            else:
                statuses = list_locks(ctx)
        if statuses:
            if not machines and ctx.owner is None and not ctx.all:
                ctx.owner = teuthology.get_user()
            if ctx.owner is not None:
                statuses = [status for status in statuses \
                                if status['locked_by'] == ctx.owner]
            if ctx.status is not None:
                statuses = [status for status in statuses \
                                if status['up'] == (ctx.status == 'up')]
            if ctx.locked is not None:
                statuses = [status for status in statuses \
                                if status['locked'] == (ctx.locked == 'true')]
            if ctx.desc is not None:
                statuses = [status for status in statuses \
                                if status['description'] == ctx.desc]
            if ctx.desc_pattern is not None:
                statuses = [status for status in statuses \
                                if status['description'] is not None and \
                                status['description'].find(ctx.desc_pattern) >= 0]
            if ctx.list:
                if ctx.brief:
                    for s in statuses:
                        locked = "un" if s['locked'] == 0 else "  "
                        mo = re.match('\w+@(\w+?)\..*', s['name'])
                        host = mo.group(1) if mo else s['name']
                        print '{host} {locked}locked {owner} "{desc}"'.format(
                            locked = locked, host = host,
                            owner=s['locked_by'], desc=s['description'])
                else:
                    print json.dumps(statuses, indent=4)
            else:
                frag = { 'targets': {} }
                for f in statuses:
                    frag['targets'][f['name']] = f['sshpubkey']
                print yaml.safe_dump(frag, default_flow_style=False)
        else:
            log.error('error retrieving lock statuses')
            ret = 1

    elif ctx.summary:
        do_summary(ctx)
        return 0

    elif ctx.lock:
        for machine in machines:
            if not lock(ctx, machine, user):
                ret = 1
                if not ctx.f:
                    return ret
            else:
                machines_to_update.append(machine)
                create_if_vm(ctx, machine)
    elif ctx.unlock:
        for machine in machines:
            if not unlock(ctx, machine, user):
                ret = 1
                if not ctx.f:
                    return ret
            else:
                machines_to_update.append(machine)
                destroy_if_vm(ctx, machine)
    elif ctx.num_to_lock:
        result = lock_many(ctx, ctx.num_to_lock, ctx.machine_type, user)
        if not result:
            ret = 1
        else:
            machines_to_update = result.keys()
            if ctx.machine_type == 'vps':
                print "Locks successful"
                print "Unable to display keys at this time (virtual machines are rebooting)."
                print "Please run teuthology-lock --list-targets once these machines come up."
            else:
                print yaml.safe_dump(dict(targets=result), default_flow_style=False)
    elif ctx.update:
        assert ctx.desc is not None or ctx.status is not None, \
            'you must specify description or status to update'
        assert ctx.owner is None, 'only description and status may be updated'
        machines_to_update = machines

    if ctx.desc is not None or ctx.status is not None:
        for machine in machines_to_update:
            update_lock(ctx, machine, ctx.desc, ctx.status)

    return ret

def update_hostkeys():
    parser = argparse.ArgumentParser(description="""
Update any hostkeys that have changed. You can list specific machines
to run on, or use -a to check all of them automatically.
""")
    parser.add_argument(
        '-t', '--targets',
        default=None,
        help='input yaml containing targets to check',
        )
    parser.add_argument(
        'machines',
        metavar='MACHINES',
        default=[],
        nargs='*',
        help='hosts to check for updated keys',
        )
    parser.add_argument(
        '-v', '--verbose',
        action='store_true',
        default=False,
        help='be more verbose',
        )
    parser.add_argument(
        '-a', '--all',
        action='store_true',
        default=False,
        help='update hostkeys of all machines in the db',
        )

    ctx = parser.parse_args()

    loglevel = logging.ERROR
    if ctx.verbose:
        loglevel = logging.DEBUG

    logging.basicConfig(
        level=loglevel,
        )

    teuthology.read_config(ctx)

    assert ctx.all or ctx.targets or ctx.machines, 'You must specify machines to update'
    if ctx.all:
        assert not ctx.targets and not ctx.machines, \
            'You can\'t specify machines with the --all option'
    machines = [canonicalize_hostname(m) for m in ctx.machines]

    if ctx.targets:
        try:
            with file(ctx.targets) as f:
                g = yaml.safe_load_all(f)
                for new in g:
                    if 'targets' in new:
                        for t in new['targets'].iterkeys():
                            machines.append(t)
        except IOError, e:
            raise argparse.ArgumentTypeError(str(e))
    
    return scan_for_locks(ctx, machines)

def keyscan_check(ctx, machines):
    locks = list_locks(ctx)
    current_locks = {}
    for lock in locks:
        current_locks[lock['name']] = lock

    if hasattr(ctx, 'all'):
        if ctx.all:
            machines = current_locks.keys()

    for i, machine in enumerate(machines):
        if '@' in machine:
            _, machines[i] = machine.rsplit('@')
    args = ['ssh-keyscan']
    args.extend(machines)
    p = subprocess.Popen(
        args=args,
        stdout=subprocess.PIPE,
        )
    out, _ = p.communicate()
    assert p.returncode == 0, 'ssh-keyscan failed'
    return (out, current_locks)

def update_keys(ctx, out, current_locks):
    ret = 0
    for key_entry in out.splitlines():
        hostname, pubkey = key_entry.split(' ', 1)
        # TODO: separate out user
        full_name = 'ubuntu@{host}'.format(host=hostname)
        log.info('Checking %s', full_name)
        assert full_name in current_locks, 'host is not in the database!'
        if current_locks[full_name]['sshpubkey'] != pubkey:
            log.info('New key found. Updating...')
            if not update_lock(ctx, full_name, sshpubkey=pubkey):
                log.error('failed to update %s!', full_name)
                ret = 1
    return ret
    
def scan_for_locks(ctx, machines):
    out, current_locks = keyscan_check(ctx, machines)
    return update_keys(ctx, out, current_locks)

def do_summary(ctx):
    lockd = collections.defaultdict(lambda: [0,0,'unknown'])
    for l in list_locks(ctx):
        if ctx.machine_type != 'all' and l['type'] != ctx.machine_type:
            continue
        who =  l['locked_by'] if l['locked'] == 1 else '(free)', l['type']
        lockd[who][0] += 1
        lockd[who][1] += l['up']         # up is 1 or 0
        lockd[who][2] = l['type']

    locks = sorted([p for p in lockd.iteritems()], key=lambda sort: (sort[1][2],sort[1][0]))
    total_count, total_up = 0, 0
    print "TYPE     COUNT  UP  OWNER"

    for (owner, (count, upcount, machinetype)) in locks:
            #if machinetype == spectype:
            print "{machinetype:8s} {count:3d}  {up:3d}  {owner}".format(count = count,
                up = upcount, owner = owner[0], machinetype=machinetype)
            total_count += count
            total_up += upcount

    print "         ---  ---"
    print "{cnt:12d}  {up:3d}".format(cnt = total_count, up = total_up)

def decanonicalize_hostname(s):
    if re.match('ubuntu@.*\.front\.sepia\.ceph\.com', s):
        s = s[len('ubuntu@'): -len('.front.sepia.ceph.com')]
    return s

def _get_downburst_exec():
    """
    First check for downburst in the user's path.
    Then check in ~/src, ~ubuntu/src, and ~teuthology/src.
    Return '' if no executable downburst is found.
    """
    path = os.environ.get('PATH', None)
    if path:
        for p in os.environ.get('PATH','').split(os.pathsep):
            pth = os.path.join(p, 'downburst')
            if os.access(pth, os.X_OK):
                return pth
    import pwd
    little_old_me = pwd.getpwuid(os.getuid()).pw_name
    for user in [little_old_me, 'ubuntu', 'teuthology']:
        pth = "/home/%s/src/downburst/virtualenv/bin/downburst" % user
        if os.access(pth, os.X_OK):
            return pth
    return ''

#
# Use downburst to create a virtual machine
#
def create_if_vm(ctx, machine_name):
    status_info = ls.get_status(ctx, machine_name)
    phys_host = status_info['vpshost']
    if not phys_host:
        return False
    try:
        vm_type = ctx.vm_type
    except AttributeError:
        vm_type = 'ubuntu'
    createMe = decanonicalize_hostname(machine_name)
    with tempfile.NamedTemporaryFile() as tmp:
        lcnfg = ctx.teuthology_config
        file_out = lcnfg.get('downburst')
        if not file_out:
            file_info = {}
            file_info['disk-size'] = lcnfg.get('disk-size', '30G')
            file_info['ram'] = lcnfg.get('ram', '1.9G')
            file_info['cpus'] = lcnfg.get('cpus', 1)
            file_info['networks'] = lcnfg.get('networks',
                    [{'source' : 'front'}])
            file_info['distro'] = lcnfg.get('distro', vm_type.lower())
            file_info['additional-disks'] = lcnfg.get(
                    'additional-disks', 3)
            file_info['additional-disks-size'] = lcnfg.get(
                    'additional-disks-size', '200G')
            file_info['arch'] = lcnfg.get('arch', 'x86_64')
            file_out = {'downburst': file_info}
        yaml.safe_dump(file_out, tmp)
        metadata = "--meta-data=%s" % tmp.name
        dbrst = _get_downburst_exec()
        if not dbrst:
            log.info("Error: no downburst executable found")
            return False
        p = subprocess.Popen([dbrst, '-c', phys_host,
                'create', metadata, createMe],
                stdout=subprocess.PIPE,stderr=subprocess.PIPE,)
        owt,err = p.communicate()
        if err:
            log.info("Downburst completed on %s: %s" %
                    (machine_name,err))
        else:
            log.info("%s created: %s" % (machine_name,owt))
    return True
#
# Use downburst to destroy a virtual machine
#
def destroy_if_vm(ctx, machine_name):
    """
    Return False only on vm downburst failures.
    """
    status_info = ls.get_status(ctx, machine_name)
    phys_host = status_info['vpshost']
    if not phys_host:
        return True
    destroyMe = decanonicalize_hostname(machine_name)
    dbrst = _get_downburst_exec()
    if not dbrst:
        log.info("Error: no downburst executable found")
        return False
    p = subprocess.Popen([dbrst, '-c', phys_host,
            'destroy', destroyMe],
            stdout=subprocess.PIPE,stderr=subprocess.PIPE,)
    owt,err = p.communicate()
    if err:
        log.info("Error occurred while deleting %s" % destroyMe)
        return False
    else:
        log.info("%s destroyed: %s" % (machine_name,owt))
    return True