#!/usr/bin/env python

#**************************************************************************
#   Copyright (C) 2008-2011 by Walter Brisken                             *
#                                                                         *
#   This program is free software; you can redistribute it and/or modify  *
#   it under the terms of the GNU General Public License as published by  *
#   the Free Software Foundation; either version 3 of the License, or     *
#   (at your option) any later version.                                   *
#                                                                         *
#   This program is distributed in the hope that it will be useful,       *
#   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
#   GNU General Public License for more details.                          *
#                                                                         *
#   You should have received a copy of the GNU General Public License     *
#   along with this program; if not, write to the                         *
#   Free Software Foundation, Inc.,                                       *
#   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
#**************************************************************************
#===========================================================================
# SVN properties (DO NOT CHANGE)
#
# $Id: genmachines 5068 2012-12-16 19:25:27Z WalterBrisken $
# $HeadURL: $
# $LastChangedRevision: 5068 $
# $Author: WalterBrisken $
# $LastChangedDate: 2012-12-16 14:25:27 -0500 (Sun, 16 Dec 2012) $
#
#============================================================================

from string import split, strip, find, upper, lower
from sys import argv, exit
from os import popen, getenv, umask
from glob import glob
import socket
import struct
import subprocess
import signal
import sys
from xml.parsers import expat
from copy import deepcopy


program = 'genmachines'
author  = 'Walter Brisken'
version = '0.16'
verdate = '20121216'

defaultDifxMessagePort = 50200
defaultDifxMessageGroup = '224.2.2.1'


def usage():
	print '\n%s ver. %s  %s %s' % (program, version, author, verdate)
	print '\nA program to find required Mark5 modules and write the machines file'
	print 'appropriate for a particular DiFX job.'
	print '\nUsage : %s [options] <input>' % argv[0]
	print '\noptions can include:'
	print '\n  -h or --help'
	print '          print this usage info and exit'
	print '\n  -v or --verbose'
	print '          increase verbosity of output'
	print '\n  -o or --overheadcores <ohc>'
	print '          set overheadcores to <ohc>, default = 1'
	print '\n  -m <machinesfile> or --machines <machinesfile>'
	print '          use <machinesfile> instead of $DIFX_MACHINES'
	print '\n  -n or --no-threads'
	print '          don\'t write a .threads file'
	print '\n  -d or --difxdb'
	print '          use difxdb database to obtain module slots'
	print '\n<input> is a DiFX .input file.'
	print '\nEnv. Var. DIFX_MACHINES must point to the machines file if no <machinesfile>'
	print 'is specifided.\n'
	exit(1)

class Parser:

    def __init__(self):
        self._parser = expat.ParserCreate()
        self._parser.StartElementHandler = self.start
        self._parser.EndElementHandler = self.end
        self._parser.CharacterDataHandler = self.data
	self.vsnA = 'none'
	self.vsnB = 'none'
	self.state = 'Unknown'
	self.unit = 'unknown'
	self.sender = 'unknown'
	self.tmp = ''
	self.ok = False

    def feed(self, sender, data):
        self._parser.Parse(data, 0)
	self.sender = sender

    def close(self):
        self._parser.Parse("", 1) # end of data
        del self._parser # get rid of circular references

    def start(self, tag, attrs):
        if tag == 'mark5Status':
		self.ok = True

    def end(self, tag):
        if tag == 'bankAVSN' and self.ok:
		if len(self.tmp) != 8:
			self.vsnA = 'none'
		else:
			self.vsnA = upper(self.tmp)
        if tag == 'bankBVSN' and self.ok:
		if len(self.tmp) != 8:
			self.vsnB = 'none'
		else:
			self.vsnB = upper(self.tmp)
	if tag == 'from':
		self.unit = lower(self.tmp)
	if tag == 'state' and self.ok:
		self.state = self.tmp

    def data(self, data):
        self.tmp = data

    def getinfo(self):
	if self.ok:
        	return [self.unit, self.vsnA, self.vsnB, self.state, self.sender]
	else:
		return ['unknown', 'none', 'none', 'Unknown', 'unknown']

def vsn_request():
	src = socket.gethostname()
	dest = '<to>mark5</to>'
	cmd = 'getvsn'

	message = \
	  '<?xml version="1.0" encoding="UTF-8"?>\n' \
	  '<difxMessage>' \
	    '<header>' \
	      '<from>%s</from>' \
	      '%s' \
	      '<mpiProcessId>-1</mpiProcessId>' \
	      '<identifier>genmachines</identifier>' \
	      '<type>DifxCommand</type>' \
	    '</header>' \
	    '<body>' \
	      '<seqNumber>0</seqNumber>' \
	      '<difxCommand>' \
	        '<command>%s</command>' \
	      '</difxCommand>' \
	    '</body>' \
	  '</difxMessage>' % (src, dest, cmd)

	return message

def getVsnsByMulticast(maxtime, modlist, verbose):
	dt = 0.2
	t = 0.0

	port = getenv('DIFX_MESSAGE_PORT')
	if port == None:
		port = defaultDifxMessagePort
	else:
		port = int(port)
	group = getenv('DIFX_MESSAGE_GROUP')
	if group == None:
		group = defaultDifxMessageGroup

	missing = deepcopy(modlist)

	message = vsn_request()

	# First send out a call for VSNs
	sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
	sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, 2)
	sock.sendto(message, (group, port))

	# Now listen for responses, until either time runs out or we get all we need
	s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
	s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
	s.bind(('', port))
	mreq = struct.pack("4sl", socket.inet_aton(group), socket.INADDR_ANY)
	s.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)
	s.settimeout(dt)
	conflicts = []
	results = []
	machines = []
	notidle = []
	while t < maxtime and len(missing) > 0:
		try:
			message, address = s.recvfrom(2048)
			sender = split(socket.gethostbyaddr(address[0])[0], '.')[0]
			if verbose > 1:
				print message
			p = Parser()
			p.feed(sender, message)
			info = p.getinfo()
			p.close()
			if info[0] == 'unknown':
				continue
			if info[0] in machines:
				continue
			machines.append(info[0])
			results.append(info)
			if info[1] in missing and info[2] in missing:
				conflicts.append(info)
			if info[1] in missing:
				missing.remove(info[1])
				if info[3] != 'Idle' and info[3] != 'Close':
					notidle.append(info[1])
			if info[2] in missing:
				missing.remove(info[2])
				if info[3] != 'Idle' and info[3] != 'Close':
					notidle.append(info[2])

		except socket.timeout:
			t += dt
		except socket.herror:
			print 'Weird: cannot gethostbyaddr for %s' % address[0]

	results.sort()
	conflicts.sort()
	missing.sort()
	notidle.sort()

	return results, conflicts, missing, notidle

def getVsnsFromInputFile(inputfile):
	vsns = []
	nds = 0
	input = open(inputfile).readlines()
	dsindices = []
	dssources = []
	dscount = 0
	dsfilecount = 0
	for inputLine in input:
		s = split(inputLine, ':')
		if len(s) < 2:
			continue;
		key = s[0].strip()
		keyparts = key.split()
		value = s[1].strip()
		if key == 'ACTIVE DATASTREAMS':
			nds = int(value)
		if len(keyparts) == 3 and keyparts[0] == 'DATASTREAM' and keyparts[2] == 'INDEX':
			dsindices.append(int(value))
		if key == 'DATA SOURCE':
			if dscount in dsindices:
				dssources.append(value)
			dscount += 1
		if len(keyparts) == 2 and keyparts[0] == 'FILE':
			# VSNs only required for MODULES - will assume files are there for now
			s = split(keyparts[1], '/')
			ds = int(strip(s[0]))

			if dssources[ds] == 'MODULE':
				if ds < nds:
					vsns.append(value)
	return (dssources, vsns)

def readmachines(machinesfile, verbose):
	machines = []
	cores = []
	ismk5 = {}
	lines = open(machinesfile).readlines()
	for l in lines:
		l = split(strip(l), '#')[0]
		s = split(l)
		if len(s) >= 2:
			machines.append(s[0])
			cores.append(int(s[1]))
			if len(s) >= 3:
				ismk5[s[0]] = int(s[2])
			else:
				if s[0][:5] == 'mark5':
					ismk5[s[0]] = 1
				else:
					ismk5[s[0]] = 0
	if verbose > 1:
		print 'MACHINES = ', machines
		print 'CORES    = ', cores
		print 'IS MK5   = ', ismk5

	return machines,cores,ismk5

def writethreads(basename, threads):
	o = open(basename+'threads', 'w')
	o.write('NUMBER OF CORES:    %d\n' % len(threads))
	for t in threads:
		o.write('%d\n' % t)
	o.close()

def writemachines(basename, hostname, machines, cores, results, vsns, dssources, ismk5, \
	overheadcores, verbose):
	dsnodes = []
	threads = []
	extrathreads = []
	quit = False

	moduleCount = 0
	headCount = 0
	for ds in dssources:
		if ds == "FILE":
			foundsuitable = False
			for m in machines:
				# don't use the head node
				if m == hostname:
					continue
				# don't use machines already used as ds nodes
				if m in dsnodes:
					continue
				# don't use mark5 machines
				if ismk5[m] == 1:
					continue
				foundsuitable = True
				dsnodes.append(m)		
				break
			if not foundsuitable:
				print "Could not find a machine not already used"
				print "Will allocate a FILE datastream to %s" % (hostname)
				dsnodes.append(hostname)
				headCount += 1
		elif ds == "MODULE":
			for r in results:
				if r[1] == vsns[moduleCount] or r[2] == vsns[moduleCount]:
					if r[0] in machines:
                                		dsnodes.append(r[0])
					else:
						dsnodes.append(r[4])
			moduleCount += 1

	for d in dsnodes:
		if not d in machines:
			print '%s not enabled in machines file' % d
			quit = True

	if quit:
		return []
	# Check if we must add the head node as a correlation node, too
	foundsuitable = False
	for m in range(len(machines)):
		if machines[m] in dsnodes:
			continue
		if cores[m] < 1:
			continue
		foundsuitable = True
		break
	if not foundsuitable:
		headCount += 1

	# write file
	o = open(basename+'machines', 'w')
	# head node
	maxslots = 1
	if hostname in machines:
		m = machines.index(hostname)
		if headCount > 0:
			maxslots = headCount + 1
		elif cores[m] > overheadcores+1:
			maxslots = 2
			extrathreads.append(cores[m] - (overheadcores+1))
	o.write('%s\n' % (hostname))
	# datastream nodes
	for d in dsnodes:
		m = machines.index(d)
		if headCount > 0:
			maxslots = headCount + 1
		elif cores[m] > overheadcores+1:
			maxslots = 2
			extrathreads.append(cores[m] - (overheadcores+1))
		else:
			maxslots = 1
		o.write('%s\n' % (d))
	# core nodes
	foundsuitable = False
	for m in range(len(machines)):
		if ismk5[machines[m]] == 1:
			continue
		if machines[m] in dsnodes:
			nthreads = cores[m] - 2
			if nthreads < 1:
				nthreads = 1
			threads.append(nthreads)
			foundsuitable = True
			o.write('%s\n' % (machines[m]))
		elif cores[m] > 0:
			threads.append(cores[m])
			foundsuitable = True
			o.write('%s\n' % (machines[m]))
	if not foundsuitable:
		print "Could not find a core machine not already used"
		print "Will allocate %s as a core, too" % (hostname)
		if hostname in machines:
			m = machines.index(hostname)
			nthreads = cores[m] - 2
			if nthreads < 1:
				nthreads = 1
		else:
			nthreads = 1
		threads.append(nthreads)
		o.write('%s\n' % (machines[m]))
	o.close()
	for e in extrathreads:
		threads.append(e)
	return threads

def uniqueVsns(vsns):
	d = {}
	for v in vsns:
		d[v] = 1
	if len(d) != len(vsns):
		return 0
	else:
		return 1

def run(files, machinesfile, overheadcores, verbose, dothreads, useDifxDb):
	ok = True

	machines, cores, ismk5 = readmachines(machinesfile, verbose)

	hostname = socket.gethostname()
	if not hostname in machines:
		print 'ERROR: hostname not in machines file : %s' % machinesfile
		exit(1)

	infile = files[0]

	basename = infile[0:-5]
	if basename + 'input' != infile:
		print 'expecting input file'
		exit(1)
				
	(dssources,vsns) = getVsnsFromInputFile(infile)


	if not uniqueVsns(vsns):
		print 'ERROR: at least one duplicate VSN exists in %s !' % infile
		exit(1)

	results, conflicts, missing, notidle = getVsnsByMulticast(5, vsns, verbose)

	if verbose > 0:
		print 'Found modules:'
		for r in results:
			print '  %-10s : %10s %10s   %s' % (r[0], r[1], r[2], r[3])

	if len(conflicts) > 0:
		ok = False
		print 'Module conflicts:'
		for c in conflicts:
			print '  %-10s : %10s %10s' % (c[0], c[1], c[2])
	
	if len(missing) > 0:
		ok = False
		print 'Missing modules:'
		for m in missing:

			slot = "unknown"
			if useDifxDb:
				child = subprocess.Popen(["getslot", m], stdout=subprocess.PIPE)
				(slot, stderr) = child.communicate()

			
			print '  %s (slot = %s )' % (m, strip(slot))

	if len(notidle) > 0:
		ok = False
		print 'Modules not ready:'
		for n in notidle:
			print '  %s' % n

	if not ok:
		return 1

	t = writemachines(basename, hostname, machines, cores, results, \
		vsns, dssources, ismk5, overheadcores, verbose)

	if len(t) == 0:
		return 1

	if dothreads:
		writethreads(basename, t)

	return 0

def signal_handler(signal, frame):
        print 'You pressed Ctrl+C!'
        sys.exit(8)

if len(argv) < 2:
	usage()

# catch ctrl+c
signal.signal(signal.SIGINT, signal_handler)


files = []
machinesfile = getenv('DIFX_MACHINES')
overheadcores = 1
verbose = 0
dothreads = True
useDifxDb = False
if getenv('DIFX_GROUP_ID'):
	umask(2)

a = 1
while a < len(argv):
	arg = argv[a]
	if arg == '-h' or arg == '--help':
		usage()
	elif arg == '-v' or arg == '--verbose':
		verbose += 1
	elif arg == '-n' or arg == '--no-threads':
		dothreads = False
	elif arg == '-m' or arg == '--machinesfile':
		a += 1
		if a >= len(argv):
			print 'No machinesfile specified!'
			exit(1)
		machinesfile = argv[a]
	elif arg == '-o' or arg == '--overheadcores':
		a += 1
		if a >= len(argv):
			print 'No overhead cores specified1'
			exit(1)
		overheadcores = int(argv[a])
	elif arg == '-d' or arg == '--difxdb':
		useDifxDb = True
	else:
		files.append(arg)
	a += 1

if len(files) != 1:
	usage()

quit = False
for f in files:
	if len(glob(f)) != 1:
		print 'File %s not found' % f
		quit = True
	
if machinesfile == None:
	print 'DIFX_MACHINES env var not defined!';
	quit = True

elif len(glob(machinesfile)) != 1:
	print 'Machinesfile %s not found.' % machinesfile
	quit = True
	
if quit:
	print 'genmachines quitting.'
	exit(1)

if verbose > 0:
	print 'DIFX_MACHINES -> %s' % machinesfile
	
v = run(files, machinesfile, overheadcores, verbose, dothreads, useDifxDb)
if v != 0:
	exit(v)