import socket, ssl, imp
import re, traceback

class Error(Exception):
    pass

class ConnectionError(Error):
    def __str__(self):
        return "Disconnected!"

class IRC(object):
    def __init__(self, nick, ident, name, host, port=6667, ssl=False, password=None, encoding="utf-8"):
        self.connected = False
        self.buffer = ""
        self.irc = ""
        self.dispatcher_prepare()
        self.conf = dict()
        self.conf["host"] = host
        self.conf["port"] = port
        self.conf["ssl"] = ssl
        self.conf["nick"] = nick
        self.conf["ident"] = ident
        self.conf["name"] = name
        self.conf["password"] = password
        self.conf["encoding"] = encoding

    def connect(self):
        self.irc = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        if self.conf["ssl"]:
            self.irc = ssl.wrap_socket(self.irc)
        self.irc.connect((self.conf["host"], self.conf["port"]))
        self.verbose_msg("Connected to %s:%s" % (self.conf["host"], self.conf["port"]))
        if self.conf["password"]:
            self.msg("PASS %s" % self.conf["password"])
        self.verbose_msg("Identifying as %s (user:%s,name:%s)" % (self.conf["nick"],self.conf["ident"],self.conf["name"]))
        self.msg("NICK %s" % self.conf["nick"])
        self.msg("USER %s %s %s :%s" % (self.conf["ident"], self.conf["host"], self.conf["nick"], self.conf["name"]))
        self.verbose_msg("function # returning from connect()")

    def quit(self):
        self.irc.msg("QUIT")
        self.irc.close()

    def dispatcher_prepare(self):
        self.patterns = dict()
        self.patterns["cmd"] = r"^\:([^ ]+)[ ]+([^ ]+)[ ]+\:?([^ ].*)?$"
        self.patterns["privmsg"] = r"^\:([^ ]+)[ ]+PRIVMSG[ ]+([^ ]+)[ ]+\:?([^ ].*)?$"
        self.patterns["kick"] = r"^\:([^ ]+)[ ]+KICK[ ]+\:?([^ ].*)?$"
        self.patterns["ping"] = r"^PING[ ]+\:?([^ ].*)?$"
        for p in self.patterns:
            self.patterns[p] = re.compile(self.patterns[p])

    def dispatch(self, msg):
        m = self.patterns["cmd"].match(msg)
        if m:
            sender = m.groups()[0]
            cmd = m.groups()[1]
            params = m.groups()[2]
            self.handle_cmd(sender,cmd,params)
        m = self.patterns["privmsg"].match(msg)
        if m:
            sender = m.groups()[0]
            target = m.groups()[1]
            params = m.groups()[2]
            self.handle_privmsg(sender,target,params)
            return
        m = self.patterns["kick"].match(msg)
        if m:
            params = m.groups()[1]
            self.handle_kick(params)
            return
        m = self.patterns["ping"].match(msg)
        if m:
            params = m.groups()[0]
            self.handle_ping(params)
            return

    def main_loop(self):
        while 1:
            try:
                read = self.irc.recv(512)
                if not read:
                    raise ConnectionError()
                self.buffer = self.buffer + read.decode(self.conf["encoding"])
                temp = self.buffer.split("\r\n")
                self.buffer = temp.pop()
                for line in temp:
                    self.verbose_msg("read < %s" % line)
                    line = line.rstrip()
                    self.dispatch(line)
            except KeyboardInterrupt as e:
                raise e
            except ConnectionError as e:
                raise e
            except:
                self.msg("error ! unhandled exception")
                traceback.print_exc()

    def verbose_msg(self, msg):
        print("<> %s" % msg)

    def msg(self, msg):
        self.verbose_msg("sending > %s" % msg)
        msg = "%s\r\n" % msg
        self.irc.send(msg.encode(self.conf["encoding"]))

    def say(self, target, msg):
        self.msg("PRIVMSG %s :%s" % (target, msg))

    def handle_kick(self, params):
        pass

    def handle_ping(self, params):
        self.msg("PONG :%s" % params)

    def handle_privmsg(self, sender, target, params):
        pass

    def handle_cmd(self, sender, cmd, params):
        if cmd=="NOTICE" and self.connected==False:
            self.connected = True

    def quit(self):
        self.msg("QUIT")
        self.irc.close()