core.py

"""
Module defining the Core class, which is the central orchestrator
of poezio and contains the main loop, the list of tabs, sets the state
of everything; it also contains global commands, completions and event
handlers but those are defined in submodules in order to avoir cluttering
this file.
"""
import logging

log = logging.getLogger(__name__)

import asyncio
import shutil
import curses
import os
import pipes
import sys
import time

from slixmpp.xmlstream.handler import Callback

from poezio import connection
from poezio import decorators
from poezio import events
from poezio import multiuserchat as muc
from poezio import tabs
from poezio import theming
from poezio import timed_events
from poezio import windows

from poezio.bookmarks import BookmarkList
from poezio.common import safeJID
from poezio.config import config, firstrun
from poezio.contact import Contact, Resource
from poezio.daemon import Executor
from poezio.fifo import Fifo
from poezio.logger import logger
from poezio.plugin_manager import PluginManager
from poezio.roster import roster
from poezio.size_manager import SizeManager
from poezio.text_buffer import TextBuffer
from poezio.theming import get_theme
from poezio import keyboard

from poezio.core.completions import CompletionCore
from poezio.core.commands import CommandCore
from poezio.core.handlers import HandlerCore
from poezio.core.structs import POSSIBLE_SHOW, DEPRECATED_ERRORS, \
        ERROR_AND_STATUS_CODES, Command, Status


class Core(object):
    """
    “Main” class of poezion
    """

    def __init__(self):
        self.completion = CompletionCore(self)
        self.command = CommandCore(self)
        self.handler = HandlerCore(self)
        # All uncaught exception are given to this callback, instead
        # of being displayed on the screen and exiting the program.
        sys.excepthook = self.on_exception
        self.connection_time = time.time()
        self.last_stream_error = None
        self.stdscr = None
        status = config.get('status')
        status = POSSIBLE_SHOW.get(status, None)
        self.status = Status(show=status,
                message=config.get('status_message'))
        self.running = True
        self.xmpp = connection.Connection()
        self.xmpp.core = self
        self.keyboard = keyboard.Keyboard()
        roster.set_node(self.xmpp.client_roster)
        decorators.refresh_wrapper.core = self
        self.bookmarks = BookmarkList()
        self.debug = False
        self.remote_fifo = None
        # a unique buffer used to store global information
        # that are displayed in almost all tabs, in an
        # information window.
        self.information_buffer = TextBuffer()
        self.information_win_size = config.get('info_win_height', section='var')
        self.information_win = windows.TextWin(300)
        self.information_buffer.add_window(self.information_win)
        self.left_tab_win = None

        self.tab_win = windows.GlobalInfoBar(self)
        # Whether the XML tab is opened
        self.xml_tab = None
        self.xml_buffer = TextBuffer()

        self.tabs = []
        self._current_tab_nb = 0
        self.previous_tab_nb = 0

        own_nick = config.get('default_nick')
        own_nick = own_nick or self.xmpp.boundjid.user
        own_nick = own_nick or os.environ.get('USER')
        own_nick = own_nick or 'poezio'
        self.own_nick = own_nick

        self.plugins_autoloaded = False
        self.plugin_manager = PluginManager(self)
        self.events = events.EventHandler()

        self.size = SizeManager(self)

        # Set to True whenever we consider that we have been disconnected
        # from the server because of a legitimate reason (bad credentials,
        # or explicit disconnect from the user for example), in that case we
        # should not try to auto-reconnect, even if auto_reconnect is true
        # in the user config.
        self.legitimate_disconnect = False

        # global commands, available from all tabs
        # a command is tuple of the form:
        # (the function executing the command. Takes a string as argument,
        #  a string representing the help message,
        #  a completion function, taking a Input as argument. Can be None)
        #  The completion function should return True if a completion was
        #  made ; False otherwise
        self.commands = {}
        self.register_initial_commands()

        # We are invisible
        if not config.get('send_initial_presence'):
            del self.commands['status']
            del self.commands['show']

        # A list of integers. For example if the user presses Alt+j, 2, 1,
        # we will insert 2, then 1 in that list, and we will finally build
        # the number 21 and use it with command_win, before clearing the
        # list.
        self.room_number_jump = []
        self.key_func = KeyDict()
        # Key bindings associated with handlers
        # and pseudo-keys used to map actions below.
        key_func = {
            "KEY_PPAGE": self.scroll_page_up,
            "KEY_NPAGE": self.scroll_page_down,
            "^B": self.scroll_line_up,
            "^F": self.scroll_line_down,
            "^X": self.scroll_half_down,
            "^S": self.scroll_half_up,
            "KEY_F(5)": self.rotate_rooms_left,
            "^P": self.rotate_rooms_left,
            "M-[-D": self.rotate_rooms_left,
            'kLFT3': self.rotate_rooms_left,
            "KEY_F(6)": self.rotate_rooms_right,
            "^N": self.rotate_rooms_right,
            "M-[-C": self.rotate_rooms_right,
            'kRIT3': self.rotate_rooms_right,
            "KEY_F(4)": self.toggle_left_pane,
            "KEY_F(7)": self.shrink_information_win,
            "KEY_F(8)": self.grow_information_win,
            "KEY_RESIZE": self.call_for_resize,
            'M-e': self.go_to_important_room,
            'M-r': self.go_to_roster,
            'M-z': self.go_to_previous_tab,
            '^L': self.full_screen_redraw,
            'M-j': self.go_to_room_number,
            'M-D': self.scroll_info_up,
            'M-C': self.scroll_info_down,
            'M-k': self.escape_next_key,
        ######## actions mappings ##########
            '_noop': lambda *args, **kwargs: None,
            '_bookmark': self.command.bookmark,
            '_bookmark_local': self.command.bookmark_local,
            '_close_tab': self.close_tab,
            '_disconnect': self.disconnect,
            '_quit': self.command.quit,
            '_redraw_screen': self.full_screen_redraw,
            '_reload_theme': self.command.theme,
            '_remove_bookmark': self.command.remove_bookmark,
            '_room_left': self.rotate_rooms_left,
            '_room_right': self.rotate_rooms_right,
            '_show_roster': self.go_to_roster,
            '_scroll_down': self.scroll_page_down,
            '_scroll_up': self.scroll_page_up,
            '_scroll_info_up': self.scroll_info_up,
            '_scroll_info_down': self.scroll_info_down,
            '_server_cycle': self.command.server_cycle,
            '_show_bookmarks': self.command.bookmarks,
            '_show_important_room': self.go_to_important_room,
            '_show_invitations': self.command.invitations,
            '_show_plugins': self.command.plugins,
            '_show_xmltab': self.command.xml_tab,
            '_toggle_pane': self.toggle_left_pane,
        ###### status actions ######
            '_available': lambda: self.command.status('available'),
            '_away': lambda: self.command.status('away'),
            '_chat': lambda: self.command.status('chat'),
            '_dnd': lambda: self.command.status('dnd'),
            '_xa': lambda: self.command.status('xa'),
        ##### Custom actions ########
            '_exc_': self.try_execute,
        }
        self.key_func.update(key_func)

        # Add handlers
        self.xmpp.add_event_handler('connected', self.handler.on_connected)
        self.xmpp.add_event_handler('connection_failed', self.handler.on_failed_connection)
        self.xmpp.add_event_handler('disconnected', self.handler.on_disconnected)
        self.xmpp.add_event_handler('stream_error', self.handler.on_stream_error)
        self.xmpp.add_event_handler('failed_all_auth', self.handler.on_failed_all_auth)
        self.xmpp.add_event_handler('no_auth', self.handler.on_no_auth)
        self.xmpp.add_event_handler("session_start", self.handler.on_session_start)
        self.xmpp.add_event_handler("session_start",
                                    self.handler.on_session_start_features)
        self.xmpp.add_event_handler("groupchat_presence",
                                    self.handler.on_groupchat_presence)
        self.xmpp.add_event_handler("groupchat_message",
                                    self.handler.on_groupchat_message)
        self.xmpp.add_event_handler("groupchat_invite",
                                    self.handler.on_groupchat_invitation)
        self.xmpp.add_event_handler("groupchat_direct_invite",
                                    self.handler.on_groupchat_direct_invitation)
        self.xmpp.add_event_handler("groupchat_decline",
                                    self.handler.on_groupchat_decline)
        self.xmpp.add_event_handler("groupchat_config_status",
                                    self.handler.on_status_codes)
        self.xmpp.add_event_handler("groupchat_subject",
                                    self.handler.on_groupchat_subject)
        self.xmpp.add_event_handler("message", self.handler.on_message)
        self.xmpp.add_event_handler("message_error", self.handler.on_error_message)
        self.xmpp.add_event_handler("receipt_received", self.handler.on_receipt)
        self.xmpp.add_event_handler("got_online", self.handler.on_got_online)
        self.xmpp.add_event_handler("got_offline", self.handler.on_got_offline)
        self.xmpp.add_event_handler("roster_update", self.handler.on_roster_update)
        self.xmpp.add_event_handler("changed_status", self.handler.on_presence)
        self.xmpp.add_event_handler("presence_error", self.handler.on_presence_error)
        self.xmpp.add_event_handler("roster_subscription_request",
                                    self.handler.on_subscription_request)
        self.xmpp.add_event_handler("roster_subscription_authorized",
                                    self.handler.on_subscription_authorized)
        self.xmpp.add_event_handler("roster_subscription_remove",
                                    self.handler.on_subscription_remove)
        self.xmpp.add_event_handler("roster_subscription_removed",
                                    self.handler.on_subscription_removed)
        self.xmpp.add_event_handler("message_xform", self.handler.on_data_form)
        self.xmpp.add_event_handler("chatstate_active",
                                    self.handler.on_chatstate_active)
        self.xmpp.add_event_handler("chatstate_composing",
                                    self.handler.on_chatstate_composing)
        self.xmpp.add_event_handler("chatstate_paused",
                                    self.handler.on_chatstate_paused)
        self.xmpp.add_event_handler("chatstate_gone",
                                    self.handler.on_chatstate_gone)
        self.xmpp.add_event_handler("chatstate_inactive",
                                    self.handler.on_chatstate_inactive)
        self.xmpp.add_event_handler("attention", self.handler.on_attention)
        self.xmpp.add_event_handler("ssl_cert", self.handler.validate_ssl)
        self.xmpp.add_event_handler("ssl_invalid_chain", self.handler.ssl_invalid_chain)
        self.xmpp.add_event_handler('carbon_received', self.handler.on_carbon_received)
        self.xmpp.add_event_handler('carbon_sent', self.handler.on_carbon_sent)
        self.xmpp.add_event_handler('http_confirm', self.handler.http_confirm)

        all_stanzas = Callback('custom matcher',
                               connection.MatchAll(None),
                               self.handler.incoming_stanza)
        self.xmpp.register_handler(all_stanzas)
        if config.get('enable_avatars'):
            self.xmpp.add_event_handler("vcard_avatar_update",
                                        self.handler.on_vcard_avatar)
            self.xmpp.add_event_handler("avatar_metadata_publish",
                                        self.handler.on_0084_avatar)
        if config.get('enable_user_tune'):
            self.xmpp.add_event_handler("user_tune_publish",
                                        self.handler.on_tune_event)
        if config.get('enable_user_nick'):
            self.xmpp.add_event_handler("user_nick_publish",
                                        self.handler.on_nick_received)
        if config.get('enable_user_mood'):
            self.xmpp.add_event_handler("user_mood_publish",
                                        self.handler.on_mood_event)
        if config.get('enable_user_activity'):
            self.xmpp.add_event_handler("user_activity_publish",
                                        self.handler.on_activity_event)
        if config.get('enable_user_gaming'):
            self.xmpp.add_event_handler("user_gaming_publish",
                                        self.handler.on_gaming_event)

        self.initial_joins = []

        self.connected_events = {}

        self.pending_invites = {}

        # a dict of the form {'config_option': [list, of, callbacks]}
        # Whenever a configuration option is changed (using /set or by
        # reloading a new config using a signal), all the associated
        # callbacks are triggered.
        # Use Core.add_configuration_handler("option", callback) to add a
        # handler
        # Note that the callback will be called when it’s changed in the
        # global section, OR in a special section.
        # As a special case, handlers can be associated with the empty
        # string option (""), they will be called for every option change
        # The callback takes two argument: the config option, and the new
        # value
        self.configuration_change_handlers = {"": []}
        self.add_configuration_handler("create_gaps",
                                       self.on_gaps_config_change)
        self.add_configuration_handler("request_message_receipts",
                                       self.on_request_receipts_config_change)
        self.add_configuration_handler("ack_message_receipts",
                                       self.on_ack_receipts_config_change)
        self.add_configuration_handler("plugins_dir",
                                       self.on_plugins_dir_config_change)
        self.add_configuration_handler("plugins_conf_dir",
                                       self.on_plugins_conf_dir_config_change)
        self.add_configuration_handler("connection_timeout_delay",
                                       self.xmpp.set_keepalive_values)
        self.add_configuration_handler("connection_check_interval",
                                       self.xmpp.set_keepalive_values)
        self.add_configuration_handler("themes_dir",
                                       theming.update_themes_dir)
        self.add_configuration_handler("theme",
                                       self.on_theme_config_change)
        self.add_configuration_handler("use_bookmarks_method",
                                       self.on_bookmarks_method_config_change)
        self.add_configuration_handler("password",
                                       self.on_password_change)
        self.add_configuration_handler("enable_vertical_tab_list",
                                       self.on_vertical_tab_list_config_change)
        self.add_configuration_handler("vertical_tab_list_size",
                                       self.on_vertical_tab_list_config_change)
        self.add_configuration_handler("deterministic_nick_colors",
                                       self.on_nick_determinism_changed)
        self.add_configuration_handler("enable_carbons",
                                       self.on_carbons_switch)
        self.add_configuration_handler("hide_user_list",
                                       self.on_hide_user_list_change)

        self.add_configuration_handler("", self.on_any_config_change)

    def on_any_config_change(self, option, value):
        """
        Update the roster, in case a roster option changed.
        """
        roster.modified()

    def add_configuration_handler(self, option, callback):
        """
        Add a callback, associated with the given option. It will be called
        each time the configuration option is changed using /set or by
        reloading the configuration with a signal
        """
        if option not in self.configuration_change_handlers:
            self.configuration_change_handlers[option] = []
        self.configuration_change_handlers[option].append(callback)

    def trigger_configuration_change(self, option, value):
        """
        Triggers all the handlers associated with the given configuration
        option
        """
        # First call the callbacks associated with any configuration change
        for callback in self.configuration_change_handlers[""]:
            callback(option, value)
        # and then the callbacks associated with this specific option, if
        # any
        if option not in self.configuration_change_handlers:
            return
        for callback in self.configuration_change_handlers[option]:
            callback(option, value)

    def on_hide_user_list_change(self, option, value):
        """
        Called when the hide_user_list option changes
        """
        self.call_for_resize()

    def on_bookmarks_method_config_change(self, option, value):
        """
        Called when the use_bookmarks_method option changes
        """
        if value not in ('pep', 'privatexml'):
            return
        self.bookmarks.preferred = value
        self.bookmarks.save(self.xmpp, core=self)

    def on_gaps_config_change(self, option, value):
        """
        Called when the option create_gaps is changed.
        Remove all gaptabs if switching from gaps to nogaps.
        """
        if value.lower() == "false":
            self.tabs = [tab for tab in self.tabs if tab]

    def on_request_receipts_config_change(self, option, value):
        """
        Called when the request_message_receipts option changes
        """
        self.xmpp.plugin['xep_0184'].auto_request = config.get(option,
                                                               default=True)

    def on_ack_receipts_config_change(self, option, value):
        """
        Called when the ack_message_receipts option changes
        """
        self.xmpp.plugin['xep_0184'].auto_ack = config.get(option, default=True)

    def on_plugins_dir_config_change(self, option, value):
        """
        Called when the plugins_dir option is changed
        """
        path = os.path.expanduser(value)
        self.plugin_manager.on_plugins_dir_change(path)

    def on_vertical_tab_list_config_change(self, option, value):
        """
        Called when the enable_vertical_tab_list option is changed
        """
        self.call_for_resize()

    def on_plugins_conf_dir_config_change(self, option, value):
        """
        Called when the plugins_conf_dir option is changed
        """
        path = os.path.expanduser(value)
        self.plugin_manager.on_plugins_conf_dir_change(path)

    def on_theme_config_change(self, option, value):
        """
        Called when the theme option is changed
        """
        error_msg = theming.reload_theme()
        if error_msg:
            self.information(error_msg, 'Warning')
        self.refresh_window()

    def on_password_change(self, option, value):
        """
        Set the new password in the slixmpp.ClientXMPP object
        """
        self.xmpp.password = value


    def on_nick_determinism_changed(self, option, value):
        """If we change the value to true, we call /recolor on all the MucTabs, to
        make the current nick colors reflect their deterministic value.
        """
        if value.lower() == "true":
            for tab in self.get_tabs(tabs.MucTab):
                tab.command_recolor('')

    def on_carbons_switch(self, option, value):
        """Whenever the user enables or disables carbons using /set, we should
        inform the server immediately, this way we do not require a restart
        for the change to take effect
        """
        if value:
            self.xmpp.plugin['xep_0280'].enable()
        else:
            self.xmpp.plugin['xep_0280'].disable()

    def reload_config(self):
        # reload all log files
        log.debug("Reloading the log files…")
        logger.reload_all()
        log.debug("Log files reloaded.")
        # reload the theme
        log.debug("Reloading the theme…")
        theming.reload_theme()
        log.debug("Theme reloaded.")
        # reload the config from the disk
        log.debug("Reloading the config…")
        # Copy the old config in a dict
        old_config = config.to_dict()
        config.read_file()
        # Compare old and current config, to trigger the callbacks of all
        # modified options
        for section in config.sections():
            old_section = old_config.get(section, {})
            for option in config.options(section):
                old_value = old_section.get(option)
                new_value = config.get(option, default="", section=section)
                if new_value != old_value:
                    self.trigger_configuration_change(option, new_value)
        log.debug("Config reloaded.")
        # in case some roster options have changed
        roster.modified()

    def sigusr_handler(self, num, stack):
        """
        Handle SIGUSR1 (10)
        When caught, reload all the possible files.
        """
        log.debug("SIGUSR1 caught, reloading the files…")
        self.reload_config()

    def exit_from_signal(self, *args, **kwargs):
        """
        Quit when receiving SIGHUP or SIGTERM or SIGPIPE

        do not save the config because it is not a normal exit
        (and only roster UI things are not yet saved)
        """
        sig = args[0]
        signals = {
                1: 'SIGHUP',
                13: 'SIGPIPE',
                15: 'SIGTERM',
                }

        log.error("%s received. Exiting…", signals[sig])
        if config.get('enable_user_mood'):
            self.xmpp.plugin['xep_0107'].stop()
        if config.get('enable_user_activity'):
            self.xmpp.plugin['xep_0108'].stop()
        if config.get('enable_user_gaming'):
            self.xmpp.plugin['xep_0196'].stop()
        self.plugin_manager.disable_plugins()
        self.disconnect('%s received' % signals.get(sig))
        self.xmpp.add_event_handler("disconnected", self.exit, disposable=True)

    def autoload_plugins(self):
        """
        Load the plugins on startup.
        """
        plugins = config.get('plugins_autoload')
        if ':' in plugins:
            for plugin in plugins.split(':'):
                self.plugin_manager.load(plugin)
        else:
            for plugin in plugins.split():
                self.plugin_manager.load(plugin)
        self.plugins_autoloaded = True

    def start(self):
        """
        Init curses, create the first tab, etc
        """
        self.stdscr = curses.initscr()
        self._init_curses(self.stdscr)
        self.call_for_resize()
        default_tab = tabs.RosterInfoTab(self)
        default_tab.on_gain_focus()
        self.tabs.append(default_tab)
        self.information('Welcome to poezio!', 'Info')
        if firstrun:
            self.information(
                'It seems that it is the first time you start poezio.\n'
                'The online help is here http://doc.poez.io/\n'
                'No room is joined by default, but you can join poezio’s'
                ' room (with /join poezio@muc.poez.io), where you can'
                ' ask for help or tell us how great it is.',
                'Help')
        self.refresh_window()
        self.xmpp.plugin['xep_0012'].begin_idle(jid=self.xmpp.boundjid)

    def exit(self, event=None):
        log.debug("exit(%s)",  event)
        asyncio.get_event_loop().stop()

    def on_exception(self, typ, value, trace):
        """
        When an exception is raised, just reset curses and call
        the original exception handler (will nicely print the traceback)
        """
        try:
            self.reset_curses()
        except:
            pass
        sys.__excepthook__(typ, value, trace)

    def sigwinch_handler(self):
        """A work-around for ncurses resize stuff, which sucks. Normally, ncurses
        catches SIGWINCH itself. In its signal handler, it updates the
        windows structures (for example the size, etc) and it
        ungetch(KEY_RESIZE). That way, the next time we call getch() we know
        that a resize occured and we can act on it. BUT poezio doesn’t call
        getch() until it knows it will return something. The problem is we
        can’t know that, because stdin is not affected by this KEY_RESIZE
        value (it is only inserted in a ncurses internal fifo that we can’t
        access).

        The (ugly) solution is to handle SIGWINCH ourself, trigger the
        change of the internal windows sizes stored in ncurses module, using
        sizes that we get using shutil, ungetch the KEY_RESIZE value and
        then call getch to handle the resize on poezio’s side properly.
        """
        size = shutil.get_terminal_size()
        curses.resizeterm(size.lines, size.columns)
        curses.ungetch(curses.KEY_RESIZE)
        self.on_input_readable()

    def on_input_readable(self):
        """
        main loop waiting for the user to press a key
        """
        def replace_line_breaks(key):
            "replace ^J with \n"
            if key == '^J':
                return '\n'
            return key
        def separate_chars_from_bindings(char_list):
            """
            returns a list of lists. For example if you give
            ['a', 'b', 'KEY_BACKSPACE', 'n', 'u'], this function returns
            [['a', 'b'], ['KEY_BACKSPACE'], ['n', 'u']]

            This way, in case of lag (for example), we handle the typed text
            by “batch” as much as possible (instead of one char at a time,
            which implies a refresh after each char, which is very slow),
            but we still handle the special chars (backspaces, arrows,
            ctrl+x ou alt+x, etc) one by one, which avoids the issue of
            printing them OR ignoring them in that case.  This should
            resolve the “my ^W are ignored when I lag ;(”.
            """
            res = []
            current = []
            for char in char_list:
                assert char
                # Transform that stupid char into what we actually meant
                if char == '\x1f':
                    char = '^/'
                if len(char) == 1:
                    current.append(char)
                else:
                    # special case for the ^I key, it’s considered as \t
                    # only when pasting some text, otherwise that’s the ^I
                    # (or M-i) key, which stands for completion by default.
                    if char == '^I' and len(char_list) != 1:
                        current.append('\t')
                        continue
                    if current:
                        res.append(current)
                        current = []
                    res.append([char])
            if current:
                res.append(current)
            return res

        log.debug("Input is readable.")
        big_char_list = [replace_key_with_bound(key)\
                         for key in self.read_keyboard()]
        log.debug("Got from keyboard: %s", (big_char_list,))

        # whether to refresh after ALL keys have been handled
        for char_list in separate_chars_from_bindings(big_char_list):
            # Special case for M-x where x is a number
            if len(char_list) == 1:
                char = char_list[0]
                if char.startswith('M-') and len(char) == 3:
                    try:
                        nb = int(char[2])
                    except ValueError:
                        pass
                    else:
                        if self.current_tab().nb == nb and config.get('go_to_previous_tab_on_alt_number'):
                            self.go_to_previous_tab()
                        else:
                            self.command.win('%d' % nb)
                # search for keyboard shortcut
                func = self.key_func.get(char, None)
                if func:
                    func()
                else:
                    self.do_command(replace_line_breaks(char), False)
            else:
                self.do_command(''.join(char_list), True)
        if self.status.show not in ('xa', 'away'):
            self.xmpp.plugin['xep_0319'].idle()
        self.doupdate()

    def save_config(self):
        """
        Save config in the file just before exit
        """
        ok = roster.save_to_config_file()
        ok = ok and config.silent_set('info_win_height',
                                      self.information_win_size,
                                      'var')
        if not ok:
            self.information('Unable to save runtime preferences'
                             ' in the config file',
                             'Error')

    def on_roster_enter_key(self, roster_row):
        """
        when enter is pressed on the roster window
        """
        if isinstance(roster_row, Contact):
            if not self.get_conversation_by_jid(roster_row.bare_jid, False):
                self.open_conversation_window(roster_row.bare_jid)
            else:
                self.focus_tab_named(roster_row.bare_jid)
        if isinstance(roster_row, Resource):
            if not self.get_conversation_by_jid(roster_row.jid,
                                                False,
                                                fallback_barejid=False):
                self.open_conversation_window(roster_row.jid)
            else:
                self.focus_tab_named(roster_row.jid)
        self.refresh_window()

    def get_conversation_messages(self):
        """
        Returns a list of all the messages in the current chat.
        If the current tab is not a ChatTab, returns None.

        Messages are namedtuples of the form
        ('txt nick_color time str_time nickname user')
        """
        if not isinstance(self.current_tab(), tabs.ChatTab):
            return None
        return self.current_tab().get_conversation_messages()

    def insert_input_text(self, text):
        """
        Insert the given text into the current input
        """
        self.do_command(text, True)


##################### Anything related to command execution ###################

    def execute(self, line):
        """
        Execute the /command or just send the line on the current room
        """
        if line == "":
            return
        if line.startswith('/'):
            command = line.strip().split()[0][1:]
            arg = line[2+len(command):] # jump the '/' and the ' '
            # example. on "/link 0 open", command = "link" and arg = "0 open"
            if command in self.commands:
                func = self.commands[command].func
                func(arg)
                return
            else:
                self.information("Unknown command (%s)" % (command),
                                 'Error')

    def exec_command(self, command):
        """
        Execute an external command on the local or a remote machine,
        depending on the conf. For example, to open a link in a browser, do
        exec_command(["firefox", "http://poezio.eu"]), and this will call
        the command on the correct computer.

        The command argument is a list of strings, not quoted or escaped in
        any way. The escaping is done here if needed.

        The remote execution is done
        by writing the command on a fifo.  That fifo has to be on the
        machine where poezio is running, and accessible (through sshfs for
        example) from the local machine (where poezio is not running). A
        very simple daemon (daemon.py) reads on that fifo, and executes any
        command that is read in it. Since we can only write strings to that
        fifo, each argument has to be pipes.quote()d. That way the
        shlex.split on the reading-side of the daemon will be safe.

        You cannot use a real command line with pipes, redirections etc, but
        this function supports a simple case redirection to file: if the
        before-last argument of the command is ">" or ">>", then the last
        argument is considered to be a filename where the command stdout
        will be written. For example you can do exec_command(["echo",
        "coucou les amis coucou coucou", ">", "output.txt"]) and this will
        work. If you try to do anything else, your |, [, <<, etc will be
        interpreted as normal command arguments, not shell special tokens.
        """
        if config.get('exec_remote'):
            # We just write the command in the fifo
            fifo_path = config.get('remote_fifo_path')
            if not self.remote_fifo:
                try:
                    self.remote_fifo = Fifo(os.path.join(fifo_path,
                                                         'poezio.fifo'),
                                            'w')
                except (OSError, IOError) as exc:
                    log.error('Could not open the fifo for writing (%s)',
                               os.path.join(fifo_path, './', 'poezio.fifo'),
                               exc_info=True)
                    self.information('Could not open the fifo '
                                     'file for writing: %s' % exc,
                                     'Error')
                    return

            args = (pipes.quote(arg.replace('\n', ' ')) for arg in command)
            command_str = ' '.join(args) + '\n'
            try:
                self.remote_fifo.write(command_str)
            except (IOError) as exc:
                log.error('Could not write in the fifo (%s): %s',
                            os.path.join(fifo_path, './', 'poezio.fifo'),
                            repr(command),
                            exc_info=True)
                self.information('Could not execute %s: %s' % (command, exc),
                                 'Error')
                self.remote_fifo = None
        else:
            executor = Executor(command)
            try:
                executor.start()
            except ValueError as exc:
                log.error('Could not execute command (%s)',
                          repr(command),
                          exc_info=True)
                self.information('%s' % exc, 'Error')


    def do_command(self, key, raw):
        """
        Execute the action associated with a key

        Or if keyboard.continuation_keys_callback is set, call it instead. See
        the comment of this variable.
        """
        if not key:
            return
        if keyboard.continuation_keys_callback is not None:
            # Reset the callback to None BEFORE calling it, because this
            # callback MAY set a new callback itself, and we don’t want to
            # erase it in that case
            cb = keyboard.continuation_keys_callback
            keyboard.continuation_keys_callback = None
            cb(key)
        else:
            self.current_tab().on_input(key, raw)


    def try_execute(self, line):
        """
        Try to execute a command in the current tab
        """
        line = '/' + line
        try:
            self.current_tab().execute_command(line)
        except:
            log.error('Execute failed (%s)', line, exc_info=True)


########################## TImed Events #######################################

    def remove_timed_event(self, event):
        """Remove an existing timed event"""
        event.handler.cancel()

    def add_timed_event(self, event):
        """Add a new timed event"""
        event.handler = asyncio.get_event_loop().call_later(event.delay,
                                                            event.callback,
                                                            *event.args)

####################### XMPP-related actions ##################################

    def get_status(self):
        """
        Get the last status that was previously set
        """
        return self.status

    def set_status(self, pres, msg):
        """
        Set our current status so we can remember
        it and use it back when needed (for example to display it
        or to use it when joining a new muc)
        """
        self.status = Status(show=pres, message=msg)
        if config.get('save_status'):
            ok = config.silent_set('status', pres if pres else '')
            msg = msg.replace('\n', '|') if msg else ''
            ok = ok and config.silent_set('status_message', msg)
            if not ok:
                self.information('Unable to save the status in '
                                 'the config file', 'Error')

    def get_bookmark_nickname(self, room_name):
        """
        Returns the nickname associated with a bookmark
        or the default nickname
        """
        bm = self.bookmarks[room_name]
        if bm:
            return bm.nick
        return self.own_nick

    def disconnect(self, msg='', reconnect=False):
        """
        Disconnect from remote server and correctly set the states of all
        parts of the client (for example, set the MucTabs as not joined, etc)
        """
        self.legitimate_disconnect = True
        msg = msg or ''
        for tab in self.get_tabs(tabs.MucTab):
            tab.command_part(msg)
        self.xmpp.disconnect()
        if reconnect:
            # Add a one-time event to reconnect as soon as we are
            # effectively disconnected
            self.xmpp.add_event_handler('disconnected', lambda event: self.xmpp.connect(), disposable=True)

    def send_message(self, msg):
        """
        Function to use in plugins to send a message in the current
        conversation.
        Returns False if the current tab is not a conversation tab
        """
        if not isinstance(self.current_tab(), tabs.ChatTab):
            return False
        self.current_tab().command_say(msg)
        return True

    def invite(self, jid, room, reason=None):
        """
        Checks if the sender supports XEP-0249, then send an invitation,
        or a mediated one if it does not.
        TODO: allow passwords
        """
        def callback(iq):
            if not iq:
                return
            if 'jabber:x:conference' in iq['disco_info'].get_features():
                self.xmpp.plugin['xep_0249'].send_invitation(
                        jid,
                        room,
                        reason=reason)
            else: # fallback
                self.xmpp.plugin['xep_0045'].invite(room, jid,
                        reason=reason or '')

        self.xmpp.plugin['xep_0030'].get_info(jid=jid, timeout=5,
                                              callback=callback)

    def get_error_message(self, stanza, deprecated=False):
        """
        Takes a stanza of the form <message type='error'><error/></message>
        and return a well formed string containing error information
        """
        sender = stanza['from']
        msg = stanza['error']['type']
        condition = stanza['error']['condition']
        code = stanza['error']['code']
        body = stanza['error']['text']
        if not body:
            if deprecated:
                if code in DEPRECATED_ERRORS:
                    body = DEPRECATED_ERRORS[code]
                else:
                    body = condition or 'Unknown error'
            else:
                if code in ERROR_AND_STATUS_CODES:
                    body = ERROR_AND_STATUS_CODES[code]
                else:
                    body = condition or 'Unknown error'
        if code:
            message = '%(from)s: %(code)s - %(msg)s: %(body)s' % {
                      'from': sender, 'msg': msg, 'body': body, 'code': code}
        else:
            message = '%(from)s: %(msg)s: %(body)s' % {
                      'from': sender, 'msg': msg, 'body': body}
        return message


####################### Tab logic-related things ##############################

    ### Tab getters ###

    def get_tabs(self, cls=None):
        "Get all the tabs of a type"
        if cls is None:
            cls = tabs.Tab
        return [tab for tab in self.tabs if isinstance(tab, cls)]

    def current_tab(self):
        """
        returns the current room, the one we are viewing
        """
        self.current_tab_nb = self.current_tab_nb
        return self.tabs[self.current_tab_nb]

    def get_conversation_by_jid(self, jid, create=True, fallback_barejid=True):
        """
        From a JID, get the tab containing the conversation with it.
        If none already exist, and create is "True", we create it
        and return it. Otherwise, we return None.

        If fallback_barejid is True, then this method will seek other
        tabs with the same barejid, instead of searching only by fulljid.
        """
        jid = safeJID(jid)
        # We first check if we have a static conversation opened
        # with this precise resource
        conversation = self.get_tab_by_name(jid.full,
                                            tabs.StaticConversationTab)
        if jid.bare == jid.full and not conversation:
            conversation = self.get_tab_by_name(jid.full,
                                                tabs.DynamicConversationTab)

        if not conversation and fallback_barejid:
            # If not, we search for a conversation with the bare jid
            conversation = self.get_tab_by_name(jid.bare,
                                                tabs.DynamicConversationTab)
            if not conversation:
                if create:
                    # We create a dynamic conversation with the bare Jid if
                    # nothing was found (and we lock it to the resource
                    # later)
                    conversation = self.open_conversation_window(jid.bare,
                                                                 False)
                else:
                    conversation = None
        return conversation

    def get_tab_by_name(self, name, typ=None):
        """
        Get the tab with the given name.
        If typ is provided, return a tab of this type only
        """
        for tab in self.tabs:
            if tab.name == name:
                if (typ and isinstance(tab, typ)) or\
                        not typ:
                    return tab
        return None

    def get_tab_by_number(self, number):
        if 0 <= number < len(self.tabs):
            return self.tabs[number]
        return None

    def add_tab(self, new_tab, focus=False):
        """
        Appends the new_tab in the tab list and
        focus it if focus==True
        """
        self.tabs.append(new_tab)
        if focus:
            self.command.win("%s" % new_tab.nb)

    def insert_tab_nogaps(self, old_pos, new_pos):
        """
        Move tabs without creating gaps
        old_pos: old position of the tab
        new_pos: desired position of the tab
        """
        tab = self.tabs[old_pos]
        if new_pos < old_pos:
            self.tabs.pop(old_pos)
            self.tabs.insert(new_pos, tab)
        elif new_pos > old_pos:
            self.tabs.insert(new_pos, tab)
            self.tabs.remove(tab)
        else:
            return False
        return True

    def insert_tab_gaps(self, old_pos, new_pos):
        """
        Move tabs and create gaps in the eventual remaining space
        old_pos: old position of the tab
        new_pos: desired position of the tab
        """
        tab = self.tabs[old_pos]
        target = None if new_pos >= len(self.tabs) else self.tabs[new_pos]
        if not target:
            if new_pos < len(self.tabs):
                old_tab = self.tabs[old_pos]
                self.tabs[new_pos], self.tabs[old_pos] = old_tab, tabs.GapTab(self)
            else:
                self.tabs.append(self.tabs[old_pos])
                self.tabs[old_pos] = tabs.GapTab(self)
        else:
            if new_pos > old_pos:
                self.tabs.insert(new_pos, tab)
                self.tabs[old_pos] = tabs.GapTab(self)
            elif new_pos < old_pos:
                self.tabs[old_pos] = tabs.GapTab(self)
                self.tabs.insert(new_pos, tab)
            else:
                return False
            i = self.tabs.index(tab)
            done = False
            # Remove the first Gap on the right in the list
            # in order to prevent global shifts when there is empty space
            while not done:
                i += 1
                if i >= len(self.tabs):
                    done = True
                elif not self.tabs[i]:
                    self.tabs.pop(i)
                    done = True
        # Remove the trailing gaps
        i = len(self.tabs) - 1
        while isinstance(self.tabs[i], tabs.GapTab):
            self.tabs.pop()
            i -= 1
        return True

    def insert_tab(self, old_pos, new_pos=99999):
        """
        Insert a tab at a position, changing the number of the following tabs
        returns False if it could not move the tab, True otherwise
        """
        if old_pos <= 0 or old_pos >= len(self.tabs):
            return False
        elif new_pos <= 0:
            return False
        elif new_pos == old_pos:
            return False
        elif not self.tabs[old_pos]:
            return False
        if config.get('create_gaps'):
            return self.insert_tab_gaps(old_pos, new_pos)
        return self.insert_tab_nogaps(old_pos, new_pos)

    ### Move actions (e.g. go to next room) ###

    def rotate_rooms_right(self, args=None):
        """
        rotate the rooms list to the right
        """
        self.current_tab().on_lose_focus()
        self.current_tab_nb += 1
        while not self.tabs[self.current_tab_nb]:
            self.current_tab_nb += 1
        self.current_tab().on_gain_focus()
        self.refresh_window()

    def rotate_rooms_left(self, args=None):
        """
        rotate the rooms list to the right
        """
        self.current_tab().on_lose_focus()
        self.current_tab_nb -= 1
        while not self.tabs[self.current_tab_nb]:
            self.current_tab_nb -= 1
        self.current_tab().on_gain_focus()
        self.refresh_window()

    def go_to_room_number(self):
        """
        Read 2 more chars and go to the tab
        with the given number
        """
        def read_next_digit(digit):
            try:
                int(digit)
            except ValueError:
                # If it is not a number, we do nothing. If it was the first
                # one, we do not wait for a second one by re-setting the
                # callback
                self.room_number_jump.clear()
            else:
                self.room_number_jump.append(digit)
                if len(self.room_number_jump) == 2:
                    arg = "".join(self.room_number_jump)
                    self.room_number_jump.clear()
                    self.command.win(arg)
                else:
                    # We need to read more digits
                    keyboard.continuation_keys_callback = read_next_digit
        keyboard.continuation_keys_callback = read_next_digit

    def go_to_roster(self):
        "Select the roster as the current tab"
        self.command.win('0')

    def go_to_previous_tab(self):
        "Go to the previous tab"
        self.command.win('%s' % (self.previous_tab_nb,))

    def go_to_important_room(self):
        """
        Go to the next room with activity, in the order defined in the
        dict tabs.STATE_PRIORITY
        """
        # shortcut
        priority = tabs.STATE_PRIORITY
        tab_refs = {}
        # put all the active tabs in a dict of lists by state
        for tab in self.tabs:
            if not tab:
                continue
            if tab.state not in tab_refs:
                tab_refs[tab.state] = [tab]
            else:
                tab_refs[tab.state].append(tab)
        # sort the state by priority and remove those with negative priority
        states = sorted(tab_refs.keys(),
                        key=(lambda x: priority.get(x, 0)),
                        reverse=True)
        states = [state for state in states if priority.get(state, -1) >= 0]

        for state in states:
            for tab in tab_refs[state]:
                if (tab.nb < self.current_tab_nb and
                    tab_refs[state][-1].nb > self.current_tab_nb):
                    continue
                self.command.win('%s' % tab.nb)
                return
        return

    def focus_tab_named(self, tab_name, type_=None):
        """Returns True if it found a tab to focus on"""
        for tab in self.tabs:
            if tab.name == tab_name:
                if (type_ and (isinstance(tab, type_))) or not type_:
                    self.command.win('%s' % (tab.nb,))
                return True
        return False

    @property
    def current_tab_nb(self):
        """Wrapper for the current tab number"""
        return self._current_tab_nb

    @current_tab_nb.setter
    def current_tab_nb(self, value):
        """
        Prevents the tab number from going over the total number of opened
        tabs, or under 0
        """
        old = self._current_tab_nb
        if value >= len(self.tabs):
            self._current_tab_nb = 0
        elif value < 0:
            self._current_tab_nb = len(self.tabs) - 1
        else:
            self._current_tab_nb = value
        if old != self._current_tab_nb and self.tabs[self._current_tab_nb]:
            self.events.trigger('tab_change', old, self._current_tab_nb)

    ### Opening actions ###

    def open_conversation_window(self, jid, focus=True):
        """
        Open a new conversation tab and focus it if needed. If a resource is
        provided, we open a StaticConversationTab, else a
        DynamicConversationTab
        """
        if safeJID(jid).resource:
            new_tab = tabs.StaticConversationTab(self, jid)
        else:
            new_tab = tabs.DynamicConversationTab(self, jid)