#!/usr/bin/python3
# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2016-2017 Lenovo
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from collections import deque
import optparse
import os
import select
import signal
import subprocess
import sys

try:
    signal.signal(signal.SIGPIPE, signal.SIG_DFL)
except AttributeError:
    pass
path = os.path.dirname(os.path.realpath(__file__))
path = os.path.realpath(os.path.join(path, '..', 'lib', 'python'))
if path.startswith('/opt'):
    sys.path.append(path)

import confluent.client as client
import confluent.sortutil as sortutil
devnull = None

def run():
    global devnull
    devnull = open(os.devnull, 'rb')
    argparser = optparse.OptionParser(
        usage="Usage: %prog [options] noderange commandexpression",
        epilog="Expressions are the same as in attributes, e.g. "
               "'ipmitool -H {hardwaremanagement.manager}' will be expanded.")
    argparser.add_option('-f', '-c', '--count', type='int', default=168,
                         help='Number of commands to run at a time')
    argparser.add_option('-k', '--security', action='store_true',
                         help='Update SSH setup')
    argparser.add_option('-F', '--sync', action='store_true',
                         help='Run the syncfiles associated with the currently completed OS profile on the noderange')
    argparser.add_option('-P', '--scripts',
                         help='Re-run specified scripts, with full path under scripts, e.g. post.d/first,firstboot.d/second')
    argparser.add_option('-m', '--maxnodes', type='int',
                    help='Specify a maximum number of '
                        'nodes to run remote ssh command to, '
                        'prompting if over the threshold')
    # among other things, FD_SETSIZE limits.  Besides, spawning too many
    # processes can be unkind for the unaware on memory pressure and such...
    #argparser.disable_interspersed_args()
    (options, args) = argparser.parse_args()
    if len(args) < 1:
        argparser.print_help()
        sys.exit(1)
    client.check_globbing(args[0])
    concurrentprocs = options.count
    c = client.Command()

    currprocs = 0
    all = set([])
    pipedesc = {}
    pendingexecs = deque()
    exitcode = 0

    c.stop_if_noderange_over(args[0], options.maxnodes)
    nodemap = {}
    cmdparms = []
    nodes = []
    for res in c.read('/noderange/{0}/nodes/'.format(args[0])):
        if 'error' in res:
            sys.stderr.write(res['error'] + '\n')
            exitcode |= res.get('errorcode', 1)
            break
        node = res['item']['href'][:-1]
        nodes.append(node)
    
    cmdstorun = []
    if options.security:
        cmdstorun.append(['run_remote', 'setupssh'])
    if options.sync:
        cmdstorun.append(['run_remote_python', 'syncfileclient'])
    if options.scripts:
        for script in options.scripts.split(','):
            cmdstorun.append(['run_remote', script])
    if not cmdstorun:
        argparser.print_help()
        sys.exit(1)
    idxbynode = {}
    cmdvbase = ['bash', '/etc/confluent/functions']
    for sshnode in nodes:
        idxbynode[sshnode] = 1
        cmdv = ['ssh', sshnode] + cmdvbase + cmdstorun[0]
        if currprocs < concurrentprocs:
            currprocs += 1
            run_cmdv(sshnode, cmdv, all, pipedesc)
        else:
            pendingexecs.append((sshnode, cmdv))
    if not all or exitcode:
        sys.exit(exitcode)
    rdy, _, _ = select.select(all, [], [], 10)
    while all:
        pernodeout = {}
        for r in rdy:
            desc = pipedesc[r]
            node = desc['node']
            data = True
            while data and select.select([r], [], [], 0)[0]:
                data = r.readline()
                if data:
                    if desc['type'] == 'stdout':
                        if node not in pernodeout:
                            pernodeout[node] = []
                        pernodeout[node].append(data)
                    else:
                        data = client.stringify(data)
                        sys.stderr.write('{0}: {1}'.format(node, data))
                        sys.stderr.flush()
                else:
                    pop = desc['popen']
                    ret = pop.poll()
                    if ret is not None:
                        exitcode = exitcode | ret
                        all.discard(r)
                        r.close()
                        if desc['type'] == 'stdout':
                            if idxbynode[node] < len(cmdstorun):
                                cmdv =  ['ssh', sshnode] + cmdvbase + cmdstorun[idxbynode[node]]
                                idxbynode[node] += 1
                                run_cmdv(node, cmdv, all, pipedesc)
                            elif pendingexecs:
                                node, cmdv = pendingexecs.popleft()
                                run_cmdv(node, cmdv, all, pipedesc)
        for node in sortutil.natural_sort(pernodeout):
            for line in pernodeout[node]:
                line = client.stringify(line)
                line = line.lstrip('\x08')
                sys.stdout.write('{0}: {1}'.format(node, line))
        sys.stdout.flush()
        if all:
            rdy, _, _ = select.select(all, [], [], 10)
    sys.exit(exitcode)


def run_cmdv(node, cmdv, all, pipedesc):
    nopen = subprocess.Popen(
        cmdv, stdin=devnull, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    pipedesc[nopen.stdout] = {'node': node, 'popen': nopen,
                              'type': 'stdout'}
    pipedesc[nopen.stderr] = {'node': node, 'popen': nopen,
                              'type': 'stderr'}
    all.add(nopen.stdout)
    all.add(nopen.stderr)


if __name__ == '__main__':
    run()