import sys
import subprocess
import os
import select
import time

class Communicator(object):
    ON_POSIX = 'posix' in sys.builtin_module_names
    WINDOWS = False
    try:
        select.poll()
        from interruptingcow import timeout
    except:
        WINDOWS = True
        pass

    def __init__(self, bot_name, command):
        self.name = bot_name
        self.process = subprocess.Popen(command, stdout=subprocess.PIPE,
                                        stdin=subprocess.PIPE, bufsize=1,
                                        close_fds=Communicator.ON_POSIX,
                                        cwd="bots/"+name+"/")
        if not Communicator.WINDOWS:
            self.pollin = select.poll()
            self.pollin.register(self.process.stdin, select.POLLOUT)

    def get_response(self):
        if Communicator.WINDOWS:
            while True:
                message = self.process.stdout.readline()
                if __debug__:
                    print "got message:"+message
                return message

        if __debug__: print "waiting for response from " + self.name
        try:
            with Communicator.timeout(self.time_limit, exception=RuntimeError):
                response = self.process.stdout.readline()
                if __debug__: print "got response from " + \
                                    self.name + " : " + response.rstrip()
                return response
        except RuntimeError:
            if __debug__: print "gave up on " + self.name
            raise RuntimeError(self.name+
                               " didn't produce a response within one second")

    def send_message(self, message):
        if __debug__: print "send message to " + self.name + " : " + message
        if Communicator.WINDOWS:
            self.process.stdin.write(message+"\n")
            self.process.stdin.flush()
            return
        try:
            with Communicator.timeout(self.time_limit, exception=RuntimeError):
                while not self.pollin.poll(0):
                    time.sleep(0.1)
                self.process.stdin.write(message+"\n")
                if __debug__: print "sent message to " + self.name
        except RuntimeError:
            if __debug__: print "gave up on " + self.name
            raise RuntimeError(self.name+
                               " didn't accept a message within one second")

def read_players():
    communicators = []
    for dir in os.listdir(r"bots/"):
        try:
            file = open("bots/"+dir+"/command.txt", 'r')
        except IOError:
            continue
        command = file.read()
        file.close()
        communicators.append(Communicator(dir,command))
    return communicators