#!/usr/bin/env python2
# coding: utf-8

# vk4xmpp gateway, v3.6
# © simpleApps, 2013 — 2018.
# Program published under the MIT license.

# Disclamer: be aware that this program's code may hurt your eyes or feelings.
# You were warned.

__author__ = "mrDoctorWho <mrdoctorwho@gmail.com>"
__license__ = "MIT"
__version__ = "3.6"

import hashlib
import logging
import os
import re
import signal
import sys
import threading
import time
from argparse import ArgumentParser

try:
	import ujson as json
except ImportError:
	import json

core = getattr(sys.modules["__main__"], "__file__", None)
root = "."
if core:
	core = os.path.abspath(core)
	root = os.path.dirname(core)
	if root:
		os.chdir(root)

sys.path.insert(0, "library")
sys.path.insert(1, "modules")
reload(sys)
sys.setdefaultencoding("utf-8")

# Now we can import our own modules
import xmpp
from itypes import Database
from stext import setVars, _
from defaults import *
from printer import *
from webtools import *

Users = {}
Semaphore = threading.Semaphore()

# command line arguments
argParser = ArgumentParser()
argParser.add_argument("-c", "--config",
	help="set the general config file destination", default="Config.txt")
argParser.add_argument("-d", "--daemon",
	help="run in daemon mode (no auto-restart)", action="store_true")
args = argParser.parse_args()
Daemon = args.daemon
Config = args.config

startTime = int(time.time())


DatabaseFile = None
TransportID = None
Host = None
Server = None
Port = None
Password = None
LAST_REPORT = None


execfile(Config)
Print("#-# Config loaded successfully.")

# logger
logger = logging.getLogger("vk4xmpp")
logger.setLevel(LOG_LEVEL)
loggerHandler = logging.FileHandler(logFile)
formatter = logging.Formatter("%(asctime)s %(levelname)s:"
	"%(name)s: %(message)s", "%d.%m.%Y %H:%M:%S")
loggerHandler.setFormatter(formatter)
logger.addHandler(loggerHandler)

# now we can import the last modules
from writer import *
from settings import *
import vkapi as api
import utils

# Setting variables
# DefLang for language id, root for the translations directory
setVars(DefLang, root)

if THREAD_STACK_SIZE:
	threading.stack_size(THREAD_STACK_SIZE)
del formatter, loggerHandler

if os.name == "posix":
	OS = "{0} {2:.16} [{4}]".format(*os.uname())
else:
	import platform
	OS = "Windows {0}".format(*platform.win32_ver())

PYTHON_VERSION = "{0} {1}.{2}.{3}".format(sys.subversion[0], *sys.version_info)

# See extensions/.example.py for more information about handlers
Handlers = {"msg01": [], "msg02": [],
			"msg03": [], "evt01": [],
			"evt02": [], "evt03": [],
			"evt04": [], "evt05": [],
			"evt06": [], "evt07": [],
			"prs01": [], "prs02": [],
			"evt08": [], "evt09": []}

Stats = {"msgin": 0,  # from vk
		"msgout": 0,  # to vk
		"method": 0}


MAX_MESSAGES_PER_REQUEST = 20

# Status code that indicates what to do with returning body from plugins
MSG_SKIP = -1
MSG_PREPEND = 0
MSG_APPEND = 1

# Timeout after which user is considered paused typing
TYPING_TIMEOUT = 5

# Timeout for friends updating
FRIENDS_UPDATE_TIMEOUT = 300


def runDatabaseQuery(query, args=(), set=False, many=True):
	"""
	Executes the given sql to the database
	Args:
		query: the sql query to execute
		args: the query argument
		set: whether to commit after the execution
		many: whether to return more than one result
	Returns:
		The query execution result
	"""
	semph = None
	if threading.currentThread() != "MainThread":
		semph = Semaphore
	with Database(DatabaseFile, semph) as db:
		db(query, args)
		if set:
			db.commit()
			result = None
		elif many:
			result = db.fetchall()
		else:
			result = db.fetchone()
	return result


def initDatabase(filename):
	"""
	Initializes database if it doesn't exist
	Args:
		filename: the database filename
	"""
	runDatabaseQuery("create table if not exists users"
		"(jid text, username text, token text, "
			"lastMsgID integer, rosterSet bool)", set=True)
	return True


def executeHandlers(type, list=()):
	"""
	Executes all handlers with the given type
	Args:
		type: the handlers type
		list: the arguments to pass to handlers
	"""
	handlers = Handlers[type]
	for handler in handlers:
		utils.execute(handler, list)


def registerHandler(type, func):
	"""
	Register a handler
	Args:
		type: the handler type
		func: the function to register
	"""
	logger.info("main: add \"%s\" to handle type %s", func.func_name, type)
	for handler in Handlers[type]:
		if handler.func_name == func.func_name:
			Handlers[type].remove(handler)
	Handlers[type].append(func)


def getGatewayRev():
	"""
	Gets gateway revision using git or custom revision number
	"""
	number, hash = 480, 0
	shell = os.popen("git describe --always &"
		"& git log --pretty=format:''").readlines()
	if shell:
		number, hash = len(shell), shell[0]
	return "#%s-%s" % (number, hash)


def vk2xmpp(id):
	"""
	Converts a numeric VK ID to a Jabber ID and vice versa
	Args:
		id: a Jabber or VK id
	Returns:
		id@TransportID if parameter id is a number
		id if parameter "id" is id@TransportID
		TransportID if the given id is equal to TransportID
	"""
	if not utils.isNumber(id) and "@" in id:
		id = id.split("@")[0]
		if utils.isNumber(id):
			id = int(id)
	elif id != TransportID:
		id = u"%s@%s" % (id, TransportID)
	return id


REVISION = getGatewayRev()

# Escape xmpp non-allowed chars
badChars = [x for x in xrange(32) if x not in (9, 10, 13)] + [57003, 65535]
escape = re.compile("|".join(unichr(x) for x in badChars),
	re.IGNORECASE | re.UNICODE | re.DOTALL).sub

sortMsg = lambda first, second: first.get("id", 0) - second.get("id", 0)
require = lambda name: os.path.exists("extensions/%s.py" % name)
isdef = lambda var: var in globals()
findUserInDB = lambda source: runDatabaseQuery("select * from users where jid=?", (source,), many=False)


class Transport(object):
	"""
	A dummy class to store settings (ATM)
	"""
	def __init__(self):
		self.settings = Settings(TransportID, user=False)


class VK(object):
	"""
	Contains methods to handle the VK stuff
	"""
	def __init__(self, token=None, source=None):
		self.token = token
		self.source = source
		self.pollConfig = {"mode": 66, "wait": 30, "act": "a_check", "version": 3}
		self.pollServer = ""
		self.pollInitialized = False
		self.engine = None
		self.online = False
		self.userID = 0
		self.methods = 0
		self.lists = []
		self.friends_fields = {"screen_name", "online"}
		self.engine = None
		self.cache = {}
		self.permissions = 0
		self.timezone = 0
		logger.debug("VK initialized (jid: %s)", source)

	def __str__(self):
		return ("user id: %s; timezone: %s; online: %s; token: %s" %
			(self.userID, self.timezone, self.online, self.token))

	def init(self):
		self.getUserPreferences()
		self.getPermissions()

	getToken = lambda self: self.engine.token

	def checkToken(self):
		"""
		Checks the token
		"""
		try:
			data = self.engine.method("users.get")
			if not data:
				raise RuntimeError("Unable to get data for user!")
		except api.VkApiError:
			logger.error("unable to check user's token, error: %s (user: %s)",
				traceback.format_exc(), self.source)
			return False
		return True

	def auth(self):
		"""
		Initializes the APIBinding object
		Returns:
			True if everything went fine
		"""
		logger.debug("VK going to authenticate (jid: %s)", self.source)
		self.engine = api.APIBinding(self.token, DEBUG_API, self.source)
		if not self.checkToken():
			raise api.TokenError("The token is invalid (jid: %s, token: %s)"
				% (self.source, self.token))
		self.online = True
		return True

	def initPoll(self):
		"""
		Initializes longpoll
		Returns:
			False: if any error occurred
			True: if everything went just fine
		"""
		self.pollInitialized = False
		logger.debug("longpoll: requesting server address (jid: %s)", self.source)
		try:
			response = self.method("messages.getLongPollServer", {"use_ssl": 1, "need_pts": 0})
		except Exception:
			response = None
		if not response:
			logger.warning("longpoll: no response!")
			return False
		self.pollServer = "https://%s" % response.pop("server")
		self.pollConfig.update(response)
		logger.debug("longpoll: server: %s (jid: %s)",
			self.pollServer, self.source)
		self.pollInitialized = True
		return True

	# TODO: move it the hell outta here
	# wtf it's still doing here?
	def makePoll(self):
		"""
		Returns:
			socket connected to the poll server
		Raises api.LongPollError if poll not yet initialized (self.pollInitialized)
		"""
		if not self.pollInitialized:
			raise api.LongPollError("The Poll wasn't initialized yet")
		return api.AsyncHTTPRequest.getOpener(self.pollServer, self.pollConfig)

	def method(self, method, args=None, force=False, notoken=False):
		"""
		This is a duplicate function of self.engine.method
		Needed to handle errors properly exactly in __main__
		Args:
			method: a VK API method
			args: method arguments
			force: whether to force execution (ignore self.online and captcha)
			notoken: whether to cut the token from the request
		Returns:
			The method execution result
		See library/vkapi.py for more information about exceptions
		"""
		args = args or {}
		result = {}
		self.methods += 1
		Stats["method"] += 1
		if not self.engine.captcha and (self.online or force):
			try:
				result = self.engine.method(method, args, notoken=notoken)
			except (api.InternalServerError, api.AccessDenied) as e:
				if force:
					raise

			except api.CaptchaNeeded as e:
				executeHandlers("evt04", (self.source, self.engine.captcha))
				self.online = False

			except api.NetworkNotFound as e:
				self.online = False

			except api.NotAllowed as e:
				if self.engine.lastMethod[0] == "messages.send":
					sendMessage(self.source,
						vk2xmpp(args.get("user_id", TransportID)),
						_("You're not allowed to perform this action."))

			except api.VkApiError as e:
				# There are several types of VkApiError
				# But the user definitely must be removed.
				# The question is: how?
				# Should we completely exterminate them or just remove?
				remove = False
				m = e.message
				# TODO: Make new exceptions for each of the conditions below
				if m == "User authorization failed: user revoke access for this token.":
					remove = True
				elif m == "User authorization failed: invalid access_token.":
					sendMessage(self.source, TransportID, m + " Please, register again")
				if remove:
					utils.runThread(removeUser, (self.source, remove))
					self.online = False
				logger.error("VK: apiError %s (jid: %s)", m, self.source)
			else:
				return result
			logger.error("VK: error %s occurred while executing"
				" method(%s) (%s) (jid: %s)",
				e.__class__.__name__, method, e.message, self.source)
			return result

	@utils.threaded
	def disconnect(self):
		"""
		Stops all user handlers and removes the user from Poll
		"""
		self.online = False
		logger.debug("VK: user %s has left", self.source)
		executeHandlers("evt06", (self,))
		self.setOffline()

	def setOffline(self):
		"""
		Sets the user status to offline
		"""
		self.method("account.setOffline")

	def setOnline(self):
		"""
		Sets the user status to online
		"""
		self.method("account.setOnline")

	@staticmethod
	def formatName(data):
		"""
		Extracts a string name from a user object
		Args:
			user: a VK user object which is a dict with the first_name and last_name keys
		Returns:
			User's first and last name
		"""
		name = escape("", "%(first_name)s %(last_name)s" % data)
		del data["first_name"]
		del data["last_name"]
		return name

	def getFriends(self, fields=None, limit=MAX_FRIENDS):
		"""
		Executes the friends.get method and formats it in the key-value style
		Example:
			{1: {"name": "Pavel Durov", "online": False}
		Args:
			fields: a list of advanced fields to receive
		Which will be added in the result values
		"""
		fields = fields or self.friends_fields
		raw = self.method("friends.get", {"fields": str.join(",", fields), "count": limit}) or {}
		raw = raw.get("items", {})
		friends = {}
		for friend in raw:
			uid = friend["id"]
			online = friend.get("online")
			if online is None:
				logger.warning("No online for friend: %d (jid: %s)", friend, self.source)
				online = False
			name = self.formatName(friend)
			friends[uid] = {"name": name, "online": online, "lists": friend.get("lists")}
			for key in fields:
				friends[uid][key] = friend.get(key)
		return friends

	@staticmethod
	def getPeerIds(conversations, source=None):
		"""
		Returns a list of peer ids that exist in the given conversations
		Args:
			conversations: list of Conversations objects
		Returns:
			A list of peer id strings
		"""
		peers = []
		if not conversations:
			logger.warning("no conversations for (jid: %s)", source)
			return peers
		for conversation in conversations:
			if isinstance(conversation, dict):
				innerConversation = conversation.get("conversation")
				if innerConversation:
					peers.append(str(innerConversation["peer"]["id"]))
		return peers

	def getMessagesBulk(self, peers, count=20, mid=0):
		"""
		Receives messages for all the conversations' peers
		25 is the maximum number of conversations we can receive in a single request
		The sky is the limit!
		Args:
			peers: a list of peer ids (strings)
			messages: a list of messages (used internally)
			count: the number of messages to receive
			uid: the last message id
		Returns:
			A list of VK Message objects
		"""
		step = 20
		messages = []
		if peers:
			cursor = 0
			for i in xrange(step, len(peers) + step, step):
				tempPeers = peers[cursor:i]
				users = ",".join(tempPeers)
				response = self.method("execute.getMessagesBulk",
					{"users": users,
					"start_message_id": mid,
					"count": count})
				if response:
					for item in response:
						item = item.get("items")
						if not item:
							continue
						messages.extend(item)
				else:
					# not sure if that's okay
					# VK is totally unpredictable now
					logger.warning("No response for execute.getMessagesBulk!"
						+" Users: %s, mid: %s (jid: %s)", users, mid, self.source)
				cursor += step
		return messages

	def getMessages(self, count=20, mid=0, uid=0, filter_="unread"):
		"""
		Gets the last messages list
		Args:
			count: the number of messages to receive
			mid: the last message id
		Returns:
			A list of VK Message objects
		"""
		if uid == 0:
			conversations = self.method("messages.getConversations", {"count": count, "filter": filter_}) or {}
			conversations = conversations.get("items")
		else:
			conversations = [{"conversation": {"peer": {"id": uid}}}]
		peers = VK.getPeerIds(conversations, self.source)
		return self.getMessagesBulk(peers, count=count, mid=mid)

	# TODO: put this in the DB
	def getUserPreferences(self):
		"""
		Receives the user's id and timezone
		Returns:
			The current user id
		"""
		if not self.userID or not self.timezone:
			data = self.method("users.get", {"fields": "timezone"})
			if data:
				data = data.pop()
				self.timezone = data.get("timezone")
				self.userID = data.get("id")
		return (self.userID, self.timezone)

	def getPermissions(self):
		"""
		Update the app permissions
		Returns:
			The current permission mask
		"""
		if not self.permissions:
			self.permissions = self.method("account.getAppPermissions")
		return self.permissions

	def getLists(self):
		"""
		Receive the list of the user friends' groups
		Returns:
			a list of user friends groups
		"""
		if not self.lists:
			self.lists = self.method("friends.getLists")
		return self.lists

	@utils.cache
	def getGroupData(self, gid, fields=None):
		"""
		Gets group data (only name so far)
		Args:
			gid: the group id
			fields: a list of advanced fields to receive
		Returns:
			The group information
		"""
		fields = fields or ["name"]
		data = self.method("groups.getById", {"group_id": abs(gid), "fields": str.join(",", fields)})
		if data:
			data = data[0]
			return data
		raise RuntimeError("Unable to get group data for %d" % gid)

	@utils.cache
	def getUserData(self, uid, fields=None):
		"""
		Gets user data. Such as name, photo, etc
		Args:
			uid: the user id (list or str)
			fields: a list of advanced fields to receive
		Returns:
			The user information
		"""
		if uid < 0:
			raise RuntimeError("Unable to get user name. User ids can't be negative: %d" % uid)
		if not fields:
			user = Users.get(self.source)
			if user and uid in user.friends:
				return user.friends[uid]
			fields = ["screen_name"]
		if isinstance(uid, (list, tuple)):
			uid = str.join(",", uid)
		data = self.method("users.get", {"user_ids": uid, "fields": str.join(",", fields)})
		if data:
			data = data[0]
			data["name"] = self.formatName(data)
			return data
		raise RuntimeError("Unable to get the user's name for %d"  % uid)

	def getName(self, id_):
		return self.getData(id_).get("name", "Unknown group (id: %s)" % id_)

	def getData(self, id_, fields=None):
		if id_ > 0:
			data = self.getUserData(id_, fields)
		else:
			data = self.getGroupData(id_, fields) 
		return data

	def sendMessage(self, body, id, mType="user_id", more={}):
		"""
		Sends message to a VK user (or a chat)
		Args:
			body: the message body
			id: the user id
			mType: the message type (user_id is for dialogs, chat_id is for chats)
			more: for advanced fields such as attachments
		Returns:
			The result of sending the message
		"""
		Stats["msgout"] += 1
		values = {mType: id, "message": body, "type": 0, "random_id": int(time.time())}
		values.update(more)
		try:
			result = self.method("messages.send", values)
		except api.VkApiError:
			crashLog("messages.send")  # this actually never happens
			result = False
		return result


class User(object):
	"""
	Handles XMPP and VK stuff
	"""
	def __init__(self, source=""):
		self.friends = {}
		self.typing = {}
		self.msgCacheByUser = {}  # the cache of associations vk mid: xmpp mid
		self.lastMsgByUser = {}  # the cache of last messages sent to user (user id: msg id)
		self.source = source  # TODO: rename to jid

		self.lastMsgID = 0
		self.rosterSet = None
		self.username = None

		self.resources = set([])
		self.settings = Settings(source)
		self.last_udate = time.time()
		self.sync = threading.Lock()
		logger.debug("User initialized (jid: %s)", self.source)

	def sendMessage(self, body, id, mType="user_id", more={}, mid=0):
		result = self.vk.sendMessage(body, id, mType, more)
		if mid:
			self.msgCacheByUser[int(id)] = {"xmpp": mid, "vk": result}
		return result

	def connect(self, username=None, password=None, token=None):
		"""
		Initializes a VK() object and tries to make an authorization if no token provided
		Args:
			username: the user's phone number or e-mail for password authentication
			password: the user's account password
			token: the user's token
		Returns:
			True if everything went fine
		"""
		logger.debug("User connecting (jid: %s)", self.source)
		exists = False
		user = findUserInDB(self.source)  # check if user registered
		if user:
			exists = True
			logger.debug("User was found in the database... (jid: %s)", self.source)
			if not token:
				logger.debug("... but no token was given. Using the one from the database (jid: %s)", self.source)
				_, _, token, self.lastMsgID, self.rosterSet = user

		if not (token or password):
			logger.warning("User wasn't found in the database and no token or password was given!")
			raise RuntimeError("Either no token or password was given!")

		if password:
			logger.debug("Going to authenticate via password (jid: %s)", self.source)
			pwd = api.PasswordLogin(username, password).login()
			token = pwd.confirm()

		self.vk = vk = VK(token, self.source)
		try:
			vk.auth()
		except api.CaptchaNeeded:
			self.sendSubPresence()
			logger.error("User: running captcha challenge (jid: %s)", self.source)
			executeHandlers("evt04", (self.source, self.vk.engine.captcha))
			return True
		else:
			logger.debug("User seems to be authenticated (jid: %s)", self.source)
			if exists:
				# Anyways, it won't hurt anyone
				runDatabaseQuery("update users set token=? where jid=?",
					(vk.getToken(), self.source), True)
			else:
				runDatabaseQuery("insert into users (jid, token, lastMsgID, rosterSet) values (?,?,?,?)",
					(self.source, vk.getToken(),
						self.lastMsgID, self.rosterSet), True)
			executeHandlers("evt07", (self,))
			vk.init()
			# TODO: move friends to VK() and check last update timeout?
			# Currently, every time we request friends a new object is being created
			# As we request it very frequently, it might be better to move
			# getFriends() to vk.init() and every time check if the list is due for the update
			self.friends = vk.getFriends()
		return vk.online

	def markRosterSet(self):
		"""
		Marks the user's roster as already set, so the gateway won't need to send it again
		"""
		self.rosterSet = True
		runDatabaseQuery("update users set rosterSet=? where jid=?",
			(self.rosterSet, self.source), True)

	def initialize(self, force=False, send=True, resource=None, first=False):
		"""
		Initializes user after the connection has been completed
		Args:
			force: force sending subscription presence
			send: whether to send the init presence
			resource: add resource in self.resources to prevent unneeded stanza sending
			first: whether to initialize the user for the first time (during registration)
		"""
		logger.debug("User: beginning user initialization (jid: %s)", self.source)
		Users[self.source] = self
		if not self.friends:
			self.friends = self.vk.getFriends()
		if force or not self.rosterSet:
			logger.debug("User: sending subscription presence with force:%s (jid: %s)",
				force, self.source)
			import rostermanager
			rostermanager.Roster.checkRosterx(self, resource)
		if send:
			self.sendInitPresence()
		if resource:
			self.resources.add(resource)
		utils.runThread(self.vk.getUserPreferences)
		if first:
			self.sendMessages(True, filter_="unread")
		else:
			self.sendMessages(True)
		Poll.add(self)
		utils.runThread(executeHandlers, ("evt05", (self,)))

	def sendInitPresence(self):
		"""
		Sends available presence to the user from all online friends
		"""
		if not self.vk.engine.captcha:
			if not self.friends:
				self.friends = self.vk.getFriends()
			logger.debug("User: sending init presence (friends count: %s) (jid %s)",
				len(self.friends), self.source)
			for uid, value in self.friends.iteritems():
				if value["online"]:
					sendPresence(self.source, vk2xmpp(uid), hash=USER_CAPS_HASH)
			sendPresence(self.source, TransportID, hash=TRANSPORT_CAPS_HASH)

	def sendOutPresence(self, destination, reason=None, all=False):
		"""
		Sends the unavailable presence to destination. Defines a reason if set.
		Args:
			destination: to whom send the stanzas
			reason: the reason why going offline
			all: send the unavailable presence from all the friends or only the ones who's online
		"""
		logger.debug("User: sending out presence to %s", self.source)
		friends = self.friends.keys()
		if not all and friends:
			friends = filter(lambda key: self.friends[key]["online"], friends)

		for uid in friends + [TransportID]:
			sendPresence(destination, vk2xmpp(uid), "unavailable", reason=reason)

	def sendSubPresence(self, dist=None):
		"""
		Sends the subscribe presence to self.source
		Args:
			dist: friends list
		"""
		dist = dist or {}
		for uid, value in dist.iteritems():
			sendPresence(self.source, vk2xmpp(uid), "subscribe", value["name"])
		sendPresence(self.source, TransportID, "subscribe", IDENTIFIER["name"])
		# TODO: Only mark roster set when we received authorized/subscribed event from the user
		if dist:
			self.markRosterSet()

	def sendMessages(self, init=False, messages=None, mid=0, uid=0, filter_="unread"):
		"""
		Sends messages from vk to xmpp and call message01 handlers
		Args:
			init: needed to know if function called at init (add time or not)
			messages: a list of pre-defined messages that would be handled and sent (w/o requesting new ones)
			mid: last message id
			uid: user id
			filter_: what filter to use (all/unread)
		"""
		with self.sync:
			date = 0
			if not messages:
				messages = self.vk.getMessages(MAX_MESSAGES_PER_REQUEST, mid or self.lastMsgID, uid, filter_)

			messages = sorted(messages, sortMsg)
			for message in messages:
				# check if message wasn't sent by our user
				if not message["out"]:
					if self.lastMsgID >= message["id"]:
						continue
					Stats["msgin"] += 1
					frm = message["from_id"]
					mid = message["id"]
					self.removeTyping(frm)
					fromjid = vk2xmpp(frm)
					body = uhtml(message["text"])
					iter_ = Handlers["msg01"].__iter__()
					for func in iter_:
						try:
							status, data = func(self, message)
						except Exception:
							status, data = MSG_APPEND, ""
							crashLog("handle.%s" % func.__name__)

						# got ignore status, continuing execution
						if status == MSG_SKIP:
							for func in iter_:
								utils.execute(func, (self, message))
							break
						elif status == MSG_APPEND:
							body += data
						elif status == MSG_PREPEND:
							body = data + body
					else:
						if self.settings.force_vk_date or init:
							date = message["date"]
						self.lastMsgByUser[frm] = mid
						sendMessage(self.source, fromjid, escape("", body), date, mid=mid)
		if messages:
			newLastMsgID = messages[-1]["id"]
			if newLastMsgID > self.lastMsgID:
				self.lastMsgID = newLastMsgID
				runDatabaseQuery("update users set lastMsgID=? where jid=?",
					(newLastMsgID, self.source), True)

	def removeTyping(self, frm):
		if frm in self.typing:
			del self.typing[frm]

	def updateTypingUsers(self, cTime):
		"""
		Sends "paused" message event to stop user from composing a message
		Sends only if last typing activity in VK was more than 7 seconds ago
		Args:
			cTime: current time
		"""
		with self.sync:
			for user, last in self.typing.items():
				if cTime - last > TYPING_TIMEOUT:
					del self.typing[user]
					sendMessage(self.source, vk2xmpp(user), typ="paused")

	def updateFriends(self, cTime):
		"""
		Updates friends list.
		Compares the current friends list to the new list
		Takes a corresponding action if any difference found
		"""
		if (cTime - self.last_udate) > FRIENDS_UPDATE_TIMEOUT and not self.vk.engine.captcha:
			if self.settings.keep_online:
				self.vk.setOnline()
			else:
				self.vk.setOffline()
			self.last_udate = cTime
			friends = self.vk.getFriends()
			if not friends:
				logger.error("updateFriends: no friends received (jid: %s).",
					self.source)
				return None

			for uid in friends:
				if uid not in self.friends:
					self.sendSubPresence({uid: friends[uid]})
			for uid in self.friends:
				if uid not in friends:
					sendPresence(self.source, vk2xmpp(uid), "unsubscribe")
			self.friends = friends

	def reauth(self):
		"""
		Tries to execute self.initialize() again and connect() if needed
		Usually needed after captcha challenge is done
		"""
		logger.debug("calling reauth for user (jid: %s)", self.source)
		if not self.vk.online:
			self.connect()
		self.initialize()

	def captchaChallenge(self, key):
		"""
		Sets the captcha key and sends it to VK
		Args:
			key: the captcha text
		"""
		engine = self.vk.engine
		engine.captcha["key"] = key
		logger.debug("retrying for user (jid: %s)", self.source)
		if engine.retry():
			self.reauth()

	def __str__(self):
		return "User(token=%s, source=%s, friends_count=%s)" % (self.vk.getToken(), self.source, len(self.friends))


def sendPresence(destination, source, pType=None, nick=None,
	reason=None, hash=None, show=None):
	"""
	Sends a presence to destination from source
	Args:
		destination: whom send the presence to
		source: who send the presence from
		pType: the presence type
		nick: add <nick> tag
		reason: set status message
		hash: add caps hash
		show: add status show
	"""
	presence = xmpp.Presence(destination, pType,
		frm=source, status=reason, show=show)
	if nick:
		presence.setTag("nick", namespace=xmpp.NS_NICK)
		presence.setTagData("nick", nick)
	if hash:
		presence.setTag("c", {"node": CAPS_NODE, "ver": hash, "hash": "sha-1"}, xmpp.NS_CAPS)
	executeHandlers("prs02", (presence, destination, source))
	sender(Component, presence)


def sendMessage(destination, source, body=None, timestamp=0, typ="active", mtype="chat", mid=0):
	"""
	Sends message to destination from source
	Args:
		destination: to whom send the message
		source: from who send the message
		body: message body
		timestamp: message timestamp (XEP-0091)
		typ: xmpp chatstates type (XEP-0085)
		mtype: the message type
		mid: message id
	"""
	msg = xmpp.Message(destination, body, mtype, frm=source)
	msg.setTag(typ, namespace=xmpp.NS_CHATSTATES)
	if timestamp:
		timestamp = time.gmtime(timestamp)
		msg.setTimestamp(time.strftime("%Y%m%dT%H:%M:%S", timestamp))
	if mid:
		msg.setID(mid)
	executeHandlers("msg03", (msg, destination, source))
	sender(Component, msg)


def sendChatMarker(destination, source, mid, typ="displayed"):
	"""
	Sends a chat marker as per XEP-0333
	Args:
		destination: to whom send the marker
		source: from who send the marker
		mid: which message id should be marked as read
		typ: marker type (displayed by default)
	"""
	msg = xmpp.Message(destination, typ="chat",frm=source)
	msg.setTag(typ, {"id": mid}, xmpp.NS_CHAT_MARKERS)
	sender(Component, msg)


def report(message):
	"""
	Critical error reporter
	"""
	global LAST_REPORT
	if Transport.settings.send_reports and message != LAST_REPORT:
		LAST_REPORT = message
		message = "Critical failure:\n%s" % message
		for admin in ADMIN_JIDS:
			sendMessage(admin, TransportID, message)


def computeCapsHash(features=TransportFeatures):
	"""
	Computes a hash which will be placed in all presence stanzas
	Args:
		features: the list of features to compute hash from
	"""
	result = "%(category)s/%(type)s//%(name)s<" % IDENTIFIER
	features = sorted(features)
	result += str.join("<", features) + "<"
	return hashlib.sha1(result).digest().encode("base64")


# TODO: rename me
def sender(cl, stanza, cb=None, args={}):
	"""
	Sends stanza. Writes a crashlog on error
	Parameters:
		cl: the xmpp.Client object
		stanza: the xmpp.Node object
		cb: callback function
		args: callback function arguments
	"""
	if cb:
		cl.SendAndCallForResponse(stanza, cb, args)
	else:
		try:
			cl.send(stanza)
		except Exception:
			disconnectHandler()


def updateCron():
	"""
	Calls the functions to update friends and typing users list
	"""
	while ALIVE:
		for user in Users.values():
			cTime = time.time()
			user.updateTypingUsers(cTime)
			user.updateFriends(cTime)
		time.sleep(2)


def calcStats():
	"""
	Returns count(*) from users database
	"""
	countOnline = len(Users)
	countTotal = runDatabaseQuery("select count(*) from users", many=False)[0]
	return [countTotal, countOnline]


def removeUser(user, roster=False, notify=True):
	"""
	Removes user from the database
	Args:
		user: User class object or jid without resource
		roster: remove vk contacts from user's roster
			(only if User class object was in the first param)
		notify: whether to let the user know that they're being exterminated
	"""
	if isinstance(user, (str, unicode)):  # unicode is the default, but... who knows
		source = user
	elif user:
		source = user.source
	else:
		raise RuntimeError("Invalid user argument: %s" % str(user))
	if notify:
		sendMessage(source, TransportID,
			_("Your record was EXTERMINATED from the database."
				" Let us know if you feel exploited."), -1)
	logger.debug("User: removing user from db (jid: %s)" % source)
	runDatabaseQuery("delete from users where jid=?", (source,), True)
	logger.debug("User: deleted (jid: %s)", source)

	user = Users.get(source)
	if user:
		del Users[source]
		if roster:
			friends = user.friends
			user.exists = False  # Make the Daleks happy
			if friends:
				logger.debug("User: removing myself from roster (jid: %s)", source)
				for id in friends.keys() + [TransportID]:
					jid = vk2xmpp(id)
					sendPresence(source, jid, "unsubscribe")
					sendPresence(source, jid, "unsubscribed")
				user.settings.exterminate()
				executeHandlers("evt03", (user,))
			user.vk.online = False


def checkPID():
	"""
	Gets a new PID and kills the previous PID
	by signal 15 and then by 9
	"""
	pid = os.getpid()
	if os.path.exists(pidFile):
		old = rFile(pidFile)
		if old:
			old = int(old)
			if pid != old:
				Print("#-# Killing the previous instance: ", False)
				try:
					os.kill(old, signal.SIGTERM)
					time.sleep(3)
					os.kill(old, signal.SIGKILL)
				except OSError as e:
					if e.errno != 3:
						Print("%d %s.\n" % (old, e.message), False)
				else:
					Print("%d killed.\n" % old, False)
	wFile(pidFile, str(pid))


def loadExtensions(dir):
	"""
	Loads extensions
	"""
	for file in os.listdir(dir):
		if not file.startswith(".") and file.endswith(".py"):
			execfile("%s/%s" % (dir, file), globals())


def connect():
	"""
	Makes a connection to the jabber server
	Returns:
		False if failed
		True if completed
	"""
	global Component
	Component = xmpp.Component(Host, debug=DEBUG_XMPPPY)
	Print("\n#-# Connecting: ", False)
	if not Component.connect((Server, Port)):
		Print("failed.\n", False)
		return False
	else:
		Print("ok.\n", False)
		Print("#-# Auth: ", False)
		if not Component.auth(TransportID, Password):
			Print("failed (%s/%s)!\n"
				% (Component.lastErr, Component.lastErrCode), True)
			return False
		else:
			Print("ok.\n", False)
			Component.RegisterDisconnectHandler(disconnectHandler)
			Component.set_send_interval(STANZA_SEND_INTERVAL)
	return True


def initializeUsers():
	"""
	Initializes users by sending them "probe" presence
	"""
	Print("#-# Initializing users", False)
	users = runDatabaseQuery("select jid from users")
	for user in users:
		Print(".", False)
		sendPresence(user[0], TransportID, "probe")
	Print("\n#-# Yay! Component %s initialized well." % TransportID)


def runMainActions():
	"""
	Runs the actions for the gateway to work well
	Initializes extensions, longpoll and modules
	Computes required hashes
	"""
	for num, event in enumerate(Handlers["evt01"]):
		utils.runThread(event, name=("extension-%d" % num))
	utils.runThread(Poll.process, name="longPoll")
	utils.runThread(updateCron)
	import modulemanager
	Manager = modulemanager.ModuleManager
	Manager.load(Manager.list())
	global USER_CAPS_HASH, TRANSPORT_CAPS_HASH
	USER_CAPS_HASH = computeCapsHash(UserFeatures)
	TRANSPORT_CAPS_HASH = computeCapsHash(TransportFeatures)


def main():
	"""
	Runs the init actions
	Checks if any other copy running and kills it
	"""
	logger.info("gateway started")
	if RUN_AS:
		import pwd
		uid = pwd.getpwnam(RUN_AS).pw_uid
		logger.warning("switching to user %s:%s", RUN_AS, uid)
		os.setuid(uid)
	checkPID()
	initDatabase(DatabaseFile)
	if connect():
		initializeUsers()
		runMainActions()
		logger.info("gateway initialized at %s", TransportID)
	else:
		disconnectHandler(False)


def disconnectHandler(crash=True):
	"""
	Handles disconnect
	Writes a crash log if the crash parameter is True
	"""
	executeHandlers("evt02")
	if crash:
		crashLog("main.disconnect")
	logger.critical("disconnecting from the server")
	try:
		Component.disconnect()
	except AttributeError:
		pass
	global ALIVE
	ALIVE = False
	if not Daemon:
		logger.warning("the gateway is going to be restarted!")
		Print("Restarting...")
		time.sleep(5)
		os.execl(sys.executable, sys.executable, *sys.argv)
	else:
		logger.info("the gateway is shutting down!")
		os._exit(-1)


def exit(sig=None, frame=None):
	"""
	Just stops the gateway and sends unavailable presence
	"""
	status = "Shutting down by %s" % ("SIGTERM" if sig == signal.SIGTERM else "SIGINT")
	Print("#! %s" % status, False)
	for user in Users.itervalues():
		user.sendOutPresence(user.source, status, all=True)
		Print("." * len(user.friends), False)
	Print("\n")
	executeHandlers("evt02")
	try:
		os.remove(pidFile)
	except OSError:
		pass
	os._exit(0)


def loop():
	"""
	The main loop which is used to call the stanza parser
	"""
	while ALIVE:
		try:
			Component.iter(1)
		except Exception:
			logger.critical("disconnected")
			crashLog("component.iter")
			disconnectHandler(True)


if __name__ == "__main__":
	signal.signal(signal.SIGTERM, exit)
	signal.signal(signal.SIGINT, exit)
	loadExtensions("extensions")
	Transport = Transport()
	from longpoll import *
	try:
		main()
		Poll.init()
	except Exception:
		crashLog("main")
		os._exit(1)
	loop()

# This is the end!