#!/usr/bin/env python2
try:
	import sys, os
	
	######### set defaultt c3 path ########################
        try:
                def_path = os.environ[ 'C3_PATH' ]
        except KeyError:
                def_path = '/opt/c3-4'
        #######################################################

	sys.path.append( def_path )
	import c3_com_obj, c3_file_obj, socket, c3_sock, re

	######## constants ####################################
	help_info = """c3 version 4.0 
	Usage: cexecs [OPTIONS] [MACHINE DEFINTIONS] command

		--help -h	= this screen
		--file -f	= file containing list of ip's if 
				  one is not supplied then
				  /etc/c3.conf will be used
		-i		= interactive mode, ask once before 
				  executing
		--head		= execute command on head node
				  does not execute on compute nodes 
				  if specified
		--all           = execute command on all the nodes
				  on all the clusters in the configuration
				  fille, ignores the [MACHINE_DEFINITONS]
				  block
		machine definitions are in the form of
		clusterName: start-end, node number"""

	backslash = re.compile( r"\\" )
	#######################################################


	######## check for arguments  #########################
	if len(sys.argv) == 1:
		print help_info
		sys.exit()
	#######################################################


	######### et default options  #########################
	to_print = 0			#not used in parallel version
	interactive = 0			#prompt before execution
	head_node = 0			#execute only on head node
	filename = "/etc/c3.conf"	#default config file
	pidlist = []			#list if pid's to wait on
	all = 0
	#######################################################


	######### internal variables ##########################
	cluster_from_file = {}
	file_set = 0
	defusername = ""
	#######################################################



	######### parse command line ##########################

	# first create one large string of the command 
	command_line_list = sys.argv[1:]
	command_line_string = ''
	for item in command_line_list:
		command_line_string = '%s %s' % (command_line_string, item)

	# object used to parse command line
	c3_command = c3_com_obj.c3_command_line( command_line_string )
	 
	# get first option
	try:
		option = c3_command.get_opt()
		while option: # while more options
			if (option == '-f') or (option == '--file'): # alternate config file
				if not file_set:
					filename = c3_command.get_opt_string()
					file_set = 1
				else:
					print "only one file name can be specified."
					sys.exit()
			elif option == '-h' or option == "--help": # print help info
				print help_info
				sys.exit()
			elif option == '-i': # ask once before executing command
				interactive = 1
			elif option == '--head': # execute only the head node
				head_node = 1
			elif option == '--all':
				all = 1;
			else: # a catch all, option supplied not valid
				print "option ", option, " is not valid"
				sys.exit()
			option = c3_command.get_opt()
	except c3_com_obj.end_of_option: #quit parsing options
		pass

	# create cluster object from command line 
	clusters = c3_com_obj.c3_cluster_list()
	 
	if all == 0:
		clusters = c3_command.get_clusters()
	else:
		c3_command.get_clusters()
	 
	# get command to execute
	command = c3_command.rest_of_command()

	#######################################################


	######### test if ssh or rsh ##########################
	try:
		transport = os.environ[ 'C3_RSH' ]
	except KeyError:
		transport = 'ssh'
	#######################################################

	######### set default user name #######################
        try:
                defusername = os.environ[ 'C3_USER' ]
        except KeyError:
                defusername = os.environ[ 'USER' ]


        ######### set filename  ##########################
        if not file_set:
                try:
                        filename = os.environ[ 'C3_CONF' ]
                except KeyError:
                        filename = '/etc/c3.conf'
        #######################################################


	######### make cluster list object from file ##########
	try: # open file & initialize file parser
		file = c3_file_obj.cluster_def( filename )
	except IOError:
		print "error opening file: ", filename
		sys.exit()

	try:
		file.get_next_cluster() # set the default cluster (first cluster in list)
		try:
			if clusters.clusters[0] ==  "/default": # if default cluster set correct cluster name
				clusters.clusters[0] = file.get_cluster_name()
				clusters.node[file.get_cluster_name()] = clusters.node["/default"]
				del clusters.node["/default"]
		except IndexError:	#will occur if --all is used
			pass

		while(1): #throws exception when no more clusters
			c_name = file.get_cluster_name() #name of cluster being parsed
			if all == 1:
				clusters.clusters.append( c_name )
				clusters.node[c_name] = []
				clusters.node[c_name].append( "")
			if c_name in clusters.clusters:
				cluster_from_file[c_name] = {}
				cluster_from_file[c_name]['external'] = file.get_external_head_node()
				cluster_from_file[c_name]['internal'] = file.get_internal_head_node()
				cluster_from_file[c_name]['nodes'] = [] #list of node names from file
				if cluster_from_file[c_name]['external']: #if a direct cluster
					index = 0
					try:
						while(1): # build list of nodes
							node_obj = file.get_next_node()
							cluster_from_file[c_name]['nodes'].append( c3_file_obj.node_obj() )
							cluster_from_file[c_name]['nodes'][index] = node_obj
							index = index + 1
					except c3_file_obj.end_of_cluster:
						pass
			file.get_next_cluster() #repeat untill no more clusters
	except c3_file_obj.no_more_clusters:
		pass
	except c3_file_obj.parse_error, error:
		print error.description
		print "somewhere around ", error.last
		sys.exit()

	#######################################################


	######### execute command on each node in cluster



	# there are two main groups, local and remote clusters
	# in each of those groups there are direct and indirect
	# modes, that is every node specified or a "link". A link
	# on a local cluster is of course invalid.

	# right now the only way I know how to check if a cluster
	# is local is to use a "gethostbyname" and compare it
	# to the head node names (both internel and externel).
	# right now that is acceptable as many tools require 
	# the function to work correctly (ssh being one of them)
	# my want to think about a better way.

	#host_ip = socket.gethostbyname( socket.gethostname() )



	if interactive: # if interactive execution, prompt once before executing
		answer = raw_input( "execute the following command(y or n): " + command + " :" )
		if re.compile( r".*n(o)?.*", re.IGNORECASE ).match( answer ):
			sys.exit()
		


	for cluster in clusters.clusters:

		print "************************", cluster, " ************************" 

		############ get machine names #############################
		try: 
			local_ip = socket.gethostbyname( socket.gethostname() )
		except socket.error:
			print "Can not resolve local hostname"
			sys.exit()
		try:
			int_ip = socket.gethostbyname( cluster_from_file[cluster]['internal'] )
		except socket.error:
			int_ip = ""
		except KeyError:
			print "Cluster ", cluster, " is not in you configuration file."
			continue
		try:
			ext_ip = socket.gethostbyname( cluster_from_file[cluster]['external'] )
		except socket.error:
			ext_ip = ""
		except TypeError:
			ext_ip = int_ip
		############################################################

		try:
			if clusters.username[cluster] == "/default":
				username = defusername
			else:
				username = clusters.username[cluster]
		except KeyError: #if --all is specified
			username = defusername

		
		pipe_list = []
		
		if head_node:   #if only execute on head node , do so
				#will execute on local cluster with ssh also
			string_to_execute = transport + " -l " + username + " " + ext_ip + " \'" + command + "\'"
			os.system( string_to_execute)
		elif cluster_from_file[cluster]['external']: # if a direct cluster
			if ext_ip == local_ip or int_ip == local_ip: # if a local cluster
				if ext_ip == "": # error conditions (just don't execute current cluster)
					print "Can not resolve ", cluster_from_file[cluster]['external']
				elif int_ip == "":
					print "Can not resolve ", cluster_from_file[cluster]['internal']

				elif clusters.node[cluster][0] != "" : #range specified on command line
					for node in clusters.node[cluster]: #for each cluster specified on the command line
						try:
							if not cluster_from_file[cluster]['nodes'][node].dead: #if machine is not dead
								node_name = cluster_from_file[cluster]['nodes'][node].name
								print "--------- " + node_name + "---------"
								sys.stdout.flush()
								string_to_execute = transport + " -l " + username + " " + node_name + " \'" +  command + " \'"
								os.system( string_to_execute )
								sys.stdout.flush()
						except IndexError:
							pass
				else:  # no range specified on command line, do all nodes
					for node in cluster_from_file[cluster]['nodes']:  # for each node in cluster
						if not node.dead: #if node not dead
							node_name = node.name
							print "--------- " + node_name + "---------"
							sys.stdout.flush()
							string_to_execute = transport + " -l " + username + " " + node_name + " \'" +  command + " \'"
							os.system( string_to_execute )
							sys.stdout.flush()
				for pid in pidlist: # wait for all processes spawned to finish
					os.waitpid(pid,0)
				for pipe in pipe_list:
					line = os.read( pipe[0], 2000 )
					while line[-1] != '\0':
						line = line + os.read( pipe[0], 2000 )
					sys.stdout.flush()
					
			else: # remote cluster
				if ext_ip == "": # error condition
					print "Can not resolve ", cluster_from_file[cluster]['external']
					sys.stdout.flush()
				else:
					# generate temprorary config file
					cluster_def_string = "cluster auto_gen {\n"
					cluster_def_string = cluster_def_string + cluster_from_file[cluster]['external'] + ":" + cluster_from_file[cluster]['internal'] + "\n"

		
					if clusters.node[cluster][0] != "" : #range specified on command line
						try:
							for node in clusters.node[cluster]: #for each node specified on command line
								if not cluster_from_file[cluster]['nodes'][node].dead: # if cluster node not dead
									node_name = cluster_from_file[cluster]['nodes'][node].name #add cluster to list
									cluster_def_string = cluster_def_string + node_name + "\n"
						except IndexError:
							pass
					else:  # no range specified on command line, do all nodes
						for node in cluster_from_file[cluster]['nodes']: # for each node in cluster
							if not node.dead: #if node not dead, add to list
									cluster_def_string = cluster_def_string +  node.name + "\n"
					cluster_def_string = cluster_def_string + "}" # close list
									
					#this is an attempt to generate a unique file name. As there is no easy way
					#for me to see the remote machine I mangle a group of relativly unique
					#identifiers. since i prepend the machine ip address if the file does not reside localy
					#it should not remotely, at the very least it should be safe to rewrite the file
					filename = "/tmp/" + local_ip + "%d" % os.getuid() + "%d" % os.getpid() 
					string_to_execute = transport + " -l " + username + " " + ext_ip + " " + def_path + "/cget --head --non_interactive " + filename
					sock = c3_sock.server_sock( string_to_execute )
					answer = sock.recieve()
					sock.close()
					while answer == 'good': #make sure file name is unique on local machine
						filename = filename + "1"
						string_to_execute = transport + " -l " + username + " " + ext_ip + " " + def_path + "/cget --head --non_interactive " + filename
						sock.__init__( string_to_execute )
						answer = sock.recieve()
						sock.close()

					FILE = open( filename, 'w' )
					FILE.write( cluster_def_string )
					FILE.close()
					# push file to remote machine
					string_to_execute = "rsync --rsh=" + transport + " " + filename + " " + username + "@" + ext_ip + ":" +  filename
					os.system( string_to_execute )
					# execute commend remotely
					string_to_execute = transport + " -l " + username + " " + ext_ip + " \' " + def_path + "/cexecs -f " + filename + "\"" + command + " \"\'"
					os.system( string_to_execute )
					# remove temporary file
					string_to_execute = transport + " -l " + username + " " + ext_ip + " /bin/rm -f " + filename
					os.system( string_to_execute )
					os.unlink( filename ) # remove local temp file
				
		else: # indirect clusters
			if int_ip == local_ip:  # can not have a indirect local cluster since if your default cluster
						# is local you would generate a circular reference
				print "error local cluster"
				sys.stdout.flush()
			else: # remote indirect cluster
				if int_ip == "": # error condition
					print "Can not resolve hostname ", cluster_from_file[cluster]['internal']
					sys.stdout.flush()
				else:
					node_list = "" # generate new node list from the command line
					if clusters.node[cluster][0] != "" : #range specified on command line
						node_list = ":%d" % clusters.node[cluster].pop(0)

						for node in clusters.node[cluster]:
							node_list = node_list + ", %d" % node	
					# execute command on remote machine
					string_to_execute = transport + " -l " + username + " " + int_ip + " \' " + def_path + "/cexecs " + node_list + " \"" + command + " \"\'"
					os.system( string_to_execute )

except KeyboardInterrupt:
	print "keyboard Interrupt\n"
