#!/usr/bin/env python2
import select
import psycopg2
import psycopg2.extensions
from knobs import router
import postgres_interfacing

class main():
    #LISTEN to postgres_channel for postgres-payload and parse for commands intended for bot, routing it to the proper submodule.
    #For use with logbot-genesis or logbot-multiple-channels-corrected on a LOCAL postgres server

    def __init__(self):
        self.my_router = router.router()
        self.my_interface = postgres_interfacing.postgres_interfacing()
    
    def parse_message(self, message):
        #parse irc message for valid command-calling syntax and return extracted command and arguments
        bot_command_prefix = self.my_interface.bot_command_prefix
        bot_command_prefix_len = len(bot_command_prefix)
        if message[:bot_command_prefix_len] in bot_command_prefix:
	    command_start_pos = bot_command_prefix_len + (len(message[bot_command_prefix_len:]) - len(message[bot_command_prefix_len:].lstrip()))
	    if message[command_start_pos:].find(" ") > -1:
	        command_end_pos = command_start_pos + message[command_start_pos:].find(" ")
	        command = message[command_start_pos:command_end_pos]
	        command_arguments = message[command_end_pos:]
	    else:
	        command = message[command_start_pos:]
	        command_arguments = ""
	    return command, command_arguments

    def send_to_command_router(self, target, source, command, command_arguments):
        #do stuff with valid commands
        command_function = "cmd_%s" % command
        try:
            route_command = getattr(self.my_router, command_function)(target, source, command_arguments)
        except AttributeError:
	    pass
        
    def listen_for_notifications(self):
        #Main Loop ===================
        #Execute a LISTEN on the 'log_new_message' channel on local postgres server.
        #If NOTIFY is recieved, feed the payload (which corresponds to an id in the 'log' table) into fetch_irc_message() to return the message.
        #Parse message and handle as configured in knobs and commands
        conn = psycopg2.connect(self.my_interface.connection_string)
        conn.set_isolation_level(psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT)
        cur = conn.cursor()
        cur.execute(self.my_interface.postgres_listen_string)
        print "Waiting for notifications on postgres channel '%s'" % self.my_interface.postgres_channel
        while 1:
	    if select.select([conn],[],[],5) == ([],[],[]):
	        print "Timeout"
	    else:
	        conn.poll()
	        while conn.notifies:
	            notify = conn.notifies.pop(0)
	            print "Got NOTIFY:", notify.pid, notify.channel, notify.payload
	            target, source, message = self.my_interface.fetch_irc_message(notify.payload)
	            print "Message: %s" % message
	            if source not in self.my_interface.ignore_list:
	                if self.parse_message(message):
		            command, command_arguments = self.parse_message(message)
		            print "Attempting to route command '%s' with arguments '%s'..." % (command, command_arguments)
		            self.send_to_command_router(target, source, command, command_arguments)
		        elif self.my_interface.route_all_notifications == True:
		            print "Routing non-command message: '%s'" % message
		            self.my_router.passive(target, source, message)
		    else:
		        print "Ignoring nick '%s'" % source
		        
if __name__ == "__main__":
    print "running"
    my_connection = main()
    my_connection.listen_for_notifications()