# Basics for Assignment 1 - SE3BB4 (Concurrency)
# January 20, 2013
# Michael Soltys

import threading, re, Queue, time

class Peers(threading.Thread):

	def __init__(self, delete_queue):
		super(Peers, self).__init__()
		self.delete_queue = delete_queue
		self.stoprequest = threading.Event()

	def run(self):
		MyName = self.getName()
		stop = 0
		while (stop == 0):
			if not self.delete_queue.empty():
				DeletePeer = self.delete_queue.get()
				if (DeletePeer != MyName):
					self.delete_queue.put(DeletePeer)
				else:
					stop = 1	
			# here peer works on other stuff...

# print currently active peers (i.e., threads)
# 'MainThread' always included, but we do not show/count it
def PrintInfoCurrentPeers():
	peer_count = threading.active_count()-1
	print "Currently %d peers: " % peer_count
	for p in threading.enumerate():
		name = p.getName()
		if (name != 'MainThread'):
			print 'Peer:', name

# data structure containing peers to delete
delete_queue = Queue.Queue()

while 1:
	execute_command = 1
	PrintInfoCurrentPeers()
	command = raw_input("Enter command: ")
	words = command.split()

	if (len(words) == 0):
		execute_command = 0

	elif (execute_command == 1 and words[0] == "addp"):
		execute_command = 0
		p = Peers(delete_queue)
		p.setName(words[1])
		p.start()

	elif (execute_command == 1 and words[0] == "delp"):
		execute_command = 0
		delete_queue.put(words[1])

	elif (execute_command == 1 and words[0] == "delallp"):
		execute_command = 0
		for p in threading.enumerate():
			delete_queue.put(p.getName())

	elif (execute_command == 1):
		print "unknown command"