#!/usr/bin/env python

#**************************************************************************
#   Copyright (C) 2008-2015 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)
#
# $Id$
# $HeadURL: $
# $LastChangedRevision$
# $Author$
# $LastChangedDate$
#
#============================================================================

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

def signal_handler(signal, frame):
	print('You pressed Ctrl+C!')
	raise KeyboardInterrupt

verNum = '0.6'
__author__="Walter Brisken"
__prog__ = os.path.basename(__file__)
__build__= "$Revision$"
__date__ ="$Date$"
__lastAuthor__="$Author$"

def usage():
	usage = ""
	usage += "A program to monitor the mark5 machines"

	return usage

class Mk5state:

	def __init__(self):
		self.ok    = False
		self.pid   = 0
		self.id    = ''
		self.mk5   = ''
		self.seq   = 0
		self.vsnA  = 'none'
		self.vsnB  = 'none'
		self.stationA = '  '
		self.stationB = '  '
		self.bank  = ' '
		self.state = 'Unknown'
		self.scan  = 0
		self.name  = ''
		self.pos   = 0L
		self.rate  = 0.0
		self.date  = 0.0
		self.pollTime = 0.0

	def getmk5(self):
		return self.mk5

class Parser:

	def __init__(self, options):
		self._parser = expat.ParserCreate()
		self._parser.StartElementHandler = self.start
		self._parser.EndElementHandler = self.end
		self._parser.CharacterDataHandler = self.data
		self.info = Mk5state()
		self.tmp = ''
		self.options = options

	def feed(self, data):
		try:
			self._parser.Parse(data, 0)
		except expat.ExpatError:
			print '\n\n XXX %s XXX' % data 

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

	def start(self, tag, attrs):
		pass

	def end(self, tag):
		if tag == 'mark5Status':
			self.info.ok = True
		if tag == 'bankAVSN':
			if len(self.tmp) != 8:
				self.info.vsnA = 'none'
			else:
				self.info.vsnA = upper(self.tmp)
				# obtain station code from DB (if enabled)
				if self.options.difxdb == True:
					child = subprocess.Popen(["difxdbModule", "--station", self.info.vsnA], stdout=subprocess.PIPE)
					(stationA, stderr) = child.communicate()
					self.info.stationA = strip(stationA)
				
		if tag == 'bankBVSN':
			if len(self.tmp) != 8:
				self.info.vsnB = 'none'
			else:
				self.info.vsnB = upper(self.tmp)
				# obtain station code from DB (if enabled)
				if self.options.difxdb == True:
					child = subprocess.Popen(["difxdbModule", "--station", self.info.vsnB], stdout=subprocess.PIPE)
					(stationB, stderr) = child.communicate()
					self.info.stationB = strip(stationB)
		if tag == 'from':
			self.info.mk5 = lower(self.tmp)
		if tag == 'state':
			self.info.state = self.tmp
		if tag == 'playRate':
			self.info.rate = float(self.tmp)
		if tag == 'dataMJD':
			self.info.date = float(self.tmp)
		if tag == 'position':
			self.info.pos = int(self.tmp)
		if tag == 'scanNumber':
			self.info.scan = int(self.tmp)
		if tag == 'scanName':
			self.info.name = self.tmp
		if tag == 'activeBank':
			self.info.bank = self.tmp

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

	def getinfo_old(self):
		return self.info.getmk5(), self.info.getstring()

	def getinfo(self):
		return self.info.getmk5(), self.info

class Display:

	def __init__(self):
		self.info = {}
		self.rows = {}
		self.curs = curses.initscr()
		curses.noecho()
		curses.cbreak()
		curses.start_color()
		curses.use_default_colors()
		curses.init_pair(1, -1, -1)
		curses.init_pair(2, curses.COLOR_RED, -1)
		self.curs.keypad(1)
		self.curs.refresh()
		self.inactiveSecs = 30 # unit is considered inactive if no message has been received for this number of seconds
		

	def close(self):
		curses.nocbreak()
		self.curs.keypad(0)
		curses.echo()
		curses.endwin()

	def displayrow(self, info, row):
		b1 = ' '
		b2 = ' '
		if info.bank == 'A':
			b1 = '*'
		elif info.bank == 'B':
			b2 = '*'

		if info.state == "inactive":
			dateStr = '%5.1f' % (time() - info.pollTime)
		elif info.date > 0.0 and info.date < 1.0:
			dateStr = '%10.4f s' % (info.date*86400.0)
		else:
			dateStr = '%12.6f' % info.date

		stationA = info.stationA
		stationB = info.stationB
		if stationA == 'Unknown':
			stationA = "  "
		if stationB == 'Unknown':
			stationB = "  "
		

		if options.difxdb == True:
			rowStr = '%10s %c%8s(%2s) %c%8s(%2s) %14s %7.2f %14d %4d %17s %13s ' % \
				 (info.mk5, b1, info.vsnA, stationA, b2, info.vsnB, stationB, info.state, \
				 info.rate, info.pos, info.scan, info.name, dateStr)
		else:
			rowStr = '%10s %c%8s %c%8s %14s %7.2f %14d %4d %17s %13s ' % \
				 (info.mk5, b1, info.vsnA, b2, info.vsnB, info.state, \
				 info.rate, info.pos, info.scan, info.name, dateStr)
			
		if info.state == "inactive":
			self.curs.addstr(row, 0, rowStr, curses.color_pair(2))
		elif info.state == "Error":
			self.curs.addstr(row, 0, rowStr, curses.color_pair(2)|curses.A_BOLD)
		else:
			self.curs.addstr(row, 0, rowStr, curses.color_pair(1))

	def newdata(self, data):
		k = data[0]
		
		if self.rows.has_key(k):
			self.info[k] = data[1]
			self.displayrow(self.info[k], self.rows[k])
		else:
			# a new machine has been found
			self.rows[k] = 0
			self.info[k] = data[1]
			keys = self.rows.keys()
			keys.sort()
			i = 0
			for k in keys:
				self.rows[k] = i
				i += 1
				self.displayrow(self.info[k], self.rows[k])

		# check for inactivity
		for k in self.rows.keys():	
			if time() - self.info[k].pollTime > self.inactiveSecs:
				self.info[k].state = "inactive"
				self.displayrow(self.info[k], self.rows[k])
				
		self.curs.refresh()

def listen(port, group, options):
	dt = 0.0
	t = 0
	maxtime = 6000

	# 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.setsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF, 768000)
	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(0.2)
	d = Display()
	try:
		while t < maxtime:
			try:
				message = s.recv(1500)
			except socket.timeout:
				t += dt
				continue

			if message[0] != '<':
				continue

			p = Parser(options)
			p.feed(message)
			machine, mk5info = p.getinfo()
			p.close()

			mk5info.pollTime = time()
			
			if mk5info.ok == False:
			 	continue
			d.newdata([machine, mk5info])
	except KeyboardInterrupt:
		d.close()
		return 0
	except:
		d.close()
		return 1
	d.close()
	return 0


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

# main
signal.signal(signal.SIGINT, signal_handler)
version = "%s version %s (revision %s)\nOriginal author: %s\nLast changes by: %s\nLast changes on: %s" % (__prog__, verNum, __build__, __author__, __lastAuthor__, __date__)

optParser = OptionParser(usage=usage(), version=version)

optParser.add_option("-d", "--difxdb", dest="difxdb", action="store_true", help="use difxdb to obtain station codes")
optParser.add_option("-p", "--port", dest="port", default = "", help="set the multicast message port (overrides DIX_MESSAGE_PORT environment)")
optParser.add_option("-g", "--group", dest="group", default = "", help="set the multicast message group (overrides DIX_MESSAGE_GROUP environment)")

(options, args) = optParser.parse_args()

if len(args) > 0:
	optParser.print_help()
	exit(1)

port = getenv('DIFX_MESSAGE_PORT')
if port == None:
	if options.port != "":
		port = options.port
	else:
		print 'DIFX_MESSAGE_PORT needs to be defined, or use -p option'
		exit(1)
port = int(port)

group = getenv('DIFX_MESSAGE_GROUP')
if group == None:
	if options.group != "":
                group = options.group
        else:
		print 'DIFX_MESSAGE_GROUP needs to be defined, or use -g option'
		exit(1)
while(listen(port, group, options)):
	pass