--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/desktop_kivy/plugins/plugin_wid_chat.py	Fri Jun 02 18:26:16 2023 +0200
@@ -0,0 +1,1280 @@
+#!/usr/bin/env python3
+
+#Libervia Desktop-Kivy
+# Copyright (C) 2016-2021 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+from functools import partial
+from pathlib import Path
+import sys
+import uuid
+import mimetypes
+from urllib.parse import urlparse
+from kivy.uix.boxlayout import BoxLayout
+from kivy.uix.gridlayout import GridLayout
+from kivy.uix.screenmanager import Screen, NoTransition
+from kivy.uix.textinput import TextInput
+from kivy.uix.label import Label
+from kivy.uix import screenmanager
+from kivy.uix.behaviors import ButtonBehavior
+from kivy.metrics import sp, dp
+from kivy.clock import Clock
+from kivy import properties
+from kivy.uix.stacklayout import StackLayout
+from kivy.uix.dropdown import DropDown
+from kivy.core.window import Window
+from libervia.backend.core import log as logging
+from libervia.backend.core.i18n import _
+from libervia.backend.core import exceptions
+from libervia.backend.tools.common import data_format
+from libervia.frontends.quick_frontend import quick_widgets
+from libervia.frontends.quick_frontend import quick_chat
+from libervia.frontends.tools import jid
+from libervia.desktop_kivy import G
+from ..core.constants import Const as C
+from ..core import cagou_widget
+from ..core import xmlui
+from ..core.image import Image, AsyncImage
+from ..core.common import Symbol, SymbolButton, JidButton, ContactButton
+from ..core.behaviors import FilterBehavior
+from ..core import menu
+from ..core.common_widgets import ImagesGallery
+
+log = logging.getLogger(__name__)
+
+PLUGIN_INFO = {
+    "name": _("chat"),
+    "main": "Chat",
+    "description": _("instant messaging with one person or a group"),
+    "icon_symbol": "chat",
+}
+
+# FIXME: OTR specific code is legacy, and only used nowadays for lock color
+# we can probably get rid of them.
+OTR_STATE_UNTRUSTED = 'untrusted'
+OTR_STATE_TRUSTED = 'trusted'
+OTR_STATE_TRUST = (OTR_STATE_UNTRUSTED, OTR_STATE_TRUSTED)
+OTR_STATE_UNENCRYPTED = 'unencrypted'
+OTR_STATE_ENCRYPTED = 'encrypted'
+OTR_STATE_ENCRYPTION = (OTR_STATE_UNENCRYPTED, OTR_STATE_ENCRYPTED)
+
+SYMBOL_UNENCRYPTED = 'lock-open'
+SYMBOL_ENCRYPTED = 'lock'
+SYMBOL_ENCRYPTED_TRUSTED = 'lock-filled'
+COLOR_UNENCRYPTED = (0.4, 0.4, 0.4, 1)
+COLOR_ENCRYPTED = (0.4, 0.4, 0.4, 1)
+COLOR_ENCRYPTED_TRUSTED = (0.29,0.87,0.0,1)
+
+# below this limit, new messages will be prepended
+INFINITE_SCROLL_LIMIT = dp(600)
+
+# File sending progress
+PROGRESS_UPDATE = 0.2 # number of seconds before next progress update
+
+
+# FIXME: a ScrollLayout was supposed to be used here, but due
+#   to https://github.com/kivy/kivy/issues/6745, a StackLayout is used for now
+class AttachmentsLayout(StackLayout):
+    """Layout for attachments in a received message"""
+    padding = properties.VariableListProperty([dp(5), dp(5), 0, dp(5)])
+    attachments = properties.ObjectProperty()
+
+
+class AttachmentsToSend(BoxLayout):
+    """Layout for attachments to be sent with current message"""
+    attachments = properties.ObjectProperty()
+    reduce_checkbox = properties.ObjectProperty()
+    show_resize = properties.BooleanProperty(False)
+
+    def on_kv_post(self, __):
+        self.attachments.bind(children=self.on_attachment)
+
+    def on_attachment(self, __, attachments):
+        if len(attachments) == 0:
+            self.show_resize = False
+
+
+class BaseAttachmentItem(BoxLayout):
+    data = properties.DictProperty()
+    progress = properties.NumericProperty(0)
+
+
+class AttachmentItem(BaseAttachmentItem):
+
+    def get_symbol(self, data):
+        media_type = data.get(C.KEY_ATTACHMENTS_MEDIA_TYPE, '')
+        main_type = media_type.split('/', 1)[0]
+        if main_type == 'image':
+            return "file-image"
+        elif main_type == 'video':
+            return "file-video"
+        elif main_type == 'audio':
+            return "file-audio"
+        else:
+            return "doc"
+
+    def on_press(self):
+        url = self.data.get('url')
+        if url:
+            G.local_platform.open_url(url, self)
+        else:
+            log.warning(f"can't find URL in {self.data}")
+
+
+class AttachmentImageItem(ButtonBehavior, BaseAttachmentItem):
+    image = properties.ObjectProperty()
+
+    def on_press(self):
+        full_size_source = self.data.get('path', self.data.get('url'))
+        gallery = ImagesGallery(sources=[full_size_source])
+        G.host.show_extra_ui(gallery)
+
+    def on_kv_post(self, __):
+        self.on_data(None, self.data)
+
+    def on_data(self, __, data):
+        if self.image is None:
+            return
+        source = data.get('preview') or data.get('path') or data.get('url')
+        if source:
+            self.image.source = source
+
+
+class AttachmentImagesCollectionItem(ButtonBehavior, GridLayout):
+    attachments = properties.ListProperty([])
+    chat = properties.ObjectProperty()
+    mess_data = properties.ObjectProperty()
+
+    def _set_preview(self, attachment, wid, preview_path):
+        attachment['preview'] = preview_path
+        wid.source = preview_path
+
+    def _set_path(self, attachment, wid, path):
+        attachment['path'] = path
+        if wid is not None:
+            # we also need a preview for the widget
+            if 'preview' in attachment:
+                wid.source = attachment['preview']
+            else:
+                G.host.bridge.image_generate_preview(
+                    path,
+                    self.chat.profile,
+                    callback=partial(self._set_preview, attachment, wid),
+                )
+
+    def on_kv_post(self, __):
+        attachments = self.attachments
+        self.clear_widgets()
+        for idx, attachment in enumerate(attachments):
+            try:
+                url = attachment['url']
+            except KeyError:
+                url = None
+                to_download = False
+            else:
+                if url.startswith("aesgcm:"):
+                    del attachment['url']
+                    # if the file is encrypted, we need to download it for decryption
+                    to_download = True
+                else:
+                    to_download = False
+
+            if idx < 3 or len(attachments) <= 4:
+                if ((self.mess_data.own_mess
+                     or self.chat.contact_list.is_in_roster(self.mess_data.from_jid))):
+                    wid = AsyncImage(size_hint=(1, 1), source="data/images/image-loading.gif")
+                    if 'preview' in attachment:
+                        wid.source = attachment["preview"]
+                    elif 'path' in attachment:
+                        G.host.bridge.image_generate_preview(
+                            attachment['path'],
+                            self.chat.profile,
+                            callback=partial(self._set_preview, attachment, wid),
+                        )
+                    elif url is None:
+                        log.warning(f"Can't find any source for {attachment}")
+                    else:
+                        # we'll download the file, the preview will then be generated
+                        to_download = True
+                else:
+                    # we don't download automatically the image if the contact is not
+                    # in roster, to avoid leaking the ip
+                    wid = Symbol(symbol="file-image")
+                self.add_widget(wid)
+            else:
+                wid = None
+
+            if to_download:
+                # the file needs to be downloaded, the widget source,
+                # attachment path, and preview will then be completed
+                G.host.download_url(
+                    url,
+                    callback=partial(self._set_path, attachment, wid),
+                    dest=C.FILE_DEST_CACHE,
+                    profile=self.chat.profile,
+                )
+
+        if len(attachments) > 4:
+            counter = Label(
+                bold=True,
+                text=f"+{len(attachments) - 3}",
+            )
+            self.add_widget(counter)
+
+    def on_press(self):
+        sources = []
+        for attachment in self.attachments:
+            source = attachment.get('path') or attachment.get('url')
+            if not source:
+                log.warning(f"no source for {attachment}")
+            else:
+                sources.append(source)
+        gallery = ImagesGallery(sources=sources)
+        G.host.show_extra_ui(gallery)
+
+
+class AttachmentToSendItem(AttachmentItem):
+    # True when the item is being sent
+    sending = properties.BooleanProperty(False)
+
+
+class MessAvatar(ButtonBehavior, Image):
+    pass
+
+
+class MessageWidget(quick_chat.MessageWidget, BoxLayout):
+    mess_data = properties.ObjectProperty()
+    mess_xhtml = properties.ObjectProperty()
+    mess_padding = (dp(5), dp(5))
+    avatar = properties.ObjectProperty()
+    delivery = properties.ObjectProperty()
+    font_size = properties.NumericProperty(sp(12))
+    right_part = properties.ObjectProperty()
+    header_box = properties.ObjectProperty()
+
+    def on_kv_post(self, __):
+        if not self.mess_data:
+            raise exceptions.InternalError(
+                "mess_data must always be set in MessageWidget")
+
+        self.mess_data.widgets.add(self)
+        self.add_attachments()
+
+    @property
+    def chat(self):
+        """return parent Chat instance"""
+        return self.mess_data.parent
+
+    def _get_from_mess_data(self, name, default):
+        if self.mess_data is None:
+            return default
+        return getattr(self.mess_data, name)
+
+    def _get_message(self):
+        """Return currently displayed message"""
+        if self.mess_data is None:
+            return ""
+        return self.mess_data.main_message
+
+    def _set_message(self, message):
+        if self.mess_data is None:
+            return False
+        if message == self.mess_data.message.get(""):
+            return False
+        self.mess_data.message = {"": message}
+        return True
+
+    message = properties.AliasProperty(
+        partial(_get_from_mess_data, name="main_message", default=""),
+        _set_message,
+        bind=['mess_data'],
+    )
+    message_xhtml = properties.AliasProperty(
+        partial(_get_from_mess_data, name="main_message_xhtml", default=""),
+        bind=['mess_data'])
+    mess_type = properties.AliasProperty(
+        partial(_get_from_mess_data, name="type", default=""), bind=['mess_data'])
+    own_mess = properties.AliasProperty(
+        partial(_get_from_mess_data, name="own_mess", default=False), bind=['mess_data'])
+    nick = properties.AliasProperty(
+        partial(_get_from_mess_data, name="nick", default=""), bind=['mess_data'])
+    time_text = properties.AliasProperty(
+        partial(_get_from_mess_data, name="time_text", default=""), bind=['mess_data'])
+
+    @property
+    def info_type(self):
+        return self.mess_data.info_type
+
+    def update(self, update_dict):
+        if 'avatar' in update_dict:
+            avatar_data = update_dict['avatar']
+            if avatar_data is None:
+                source = G.host.get_default_avatar()
+            else:
+                source = avatar_data['path']
+            self.avatar.source = source
+        if 'status' in update_dict:
+            status = update_dict['status']
+            self.delivery.text =  '\u2714' if status == 'delivered' else ''
+
+    def _set_path(self, data, path):
+        """Set path of decrypted file to an item"""
+        data['path'] = path
+
+    def add_attachments(self):
+        """Add attachments layout + attachments item"""
+        attachments = self.mess_data.attachments
+        if not attachments:
+            return
+        root_layout = AttachmentsLayout()
+        self.right_part.add_widget(root_layout)
+        layout = root_layout.attachments
+
+        image_attachments = []
+        other_attachments = []
+        # we first separate images and other attachments, so we know if we need
+        # to use an image collection
+        for attachment in attachments:
+            media_type = attachment.get(C.KEY_ATTACHMENTS_MEDIA_TYPE, '')
+            main_type = media_type.split('/', 1)[0]
+            # GIF images are really badly handled by Kivy, the memory
+            # consumption explode, and the images frequencies are not handled
+            # correctly, thus we can't display them and we consider them as
+            # other attachment, so user can open the item with appropriate
+            # software.
+            if main_type == 'image' and media_type != "image/gif":
+                image_attachments.append(attachment)
+            else:
+                other_attachments.append(attachment)
+
+        if len(image_attachments) > 1:
+            collection = AttachmentImagesCollectionItem(
+                attachments=image_attachments,
+                chat=self.chat,
+                mess_data=self.mess_data,
+            )
+            layout.add_widget(collection)
+        elif image_attachments:
+            attachment = image_attachments[0]
+            # to avoid leaking IP address, we only display image if the contact is in
+            # roster
+            if ((self.mess_data.own_mess
+                 or self.chat.contact_list.is_in_roster(self.mess_data.from_jid))):
+                try:
+                    url = urlparse(attachment['url'])
+                except KeyError:
+                    item = AttachmentImageItem(data=attachment)
+                else:
+                    if url.scheme == "aesgcm":
+                        # we remove the URL now, we'll replace it by
+                        # the local decrypted version
+                        del attachment['url']
+                        item = AttachmentImageItem(data=attachment)
+                        G.host.download_url(
+                            url.geturl(),
+                            callback=partial(self._set_path, item.data),
+                            dest=C.FILE_DEST_CACHE,
+                            profile=self.chat.profile,
+                        )
+                    else:
+                        item = AttachmentImageItem(data=attachment)
+            else:
+                item = AttachmentItem(data=attachment)
+
+            layout.add_widget(item)
+
+        for attachment in other_attachments:
+            item = AttachmentItem(data=attachment)
+            layout.add_widget(item)
+
+
+class MessageInputBox(BoxLayout):
+    message_input = properties.ObjectProperty()
+
+    def send_text(self):
+        self.message_input.send_text()
+
+
+class MessageInputWidget(TextInput):
+
+    def keyboard_on_key_down(self, window, keycode, text, modifiers):
+        # We don't send text when shift is pressed to be able to add line feeds
+        # (i.e. multi-lines messages). We don't send on Android either as the
+        # send button appears on this platform.
+        if (keycode[-1] == "enter"
+            and "shift" not in modifiers
+            and sys.platform != 'android'):
+            self.send_text()
+        else:
+            return super(MessageInputWidget, self).keyboard_on_key_down(
+                window, keycode, text, modifiers)
+
+    def send_text(self):
+        self.dispatch('on_text_validate')
+
+
+class TransferButton(SymbolButton):
+    chat = properties.ObjectProperty()
+
+    def on_release(self, *args):
+        menu.TransferMenu(
+            encrypted=self.chat.encrypted,
+            callback=self.chat.transfer_file,
+        ).show(self)
+
+
+class ExtraMenu(DropDown):
+    chat = properties.ObjectProperty()
+
+    def on_select(self, menu):
+        if menu == 'bookmark':
+            G.host.bridge.menu_launch(C.MENU_GLOBAL, ("groups", "bookmarks"),
+                                     {}, C.NO_SECURITY_LIMIT, self.chat.profile,
+                                     callback=partial(
+                                        G.host.action_manager, profile=self.chat.profile),
+                                     errback=G.host.errback)
+        elif menu == 'close':
+            if self.chat.type == C.CHAT_GROUP:
+                # for MUC, we have to indicate the backend that we've left
+                G.host.bridge.muc_leave(self.chat.target, self.chat.profile)
+            else:
+                # for one2one, backend doesn't keep any state, so we just delete the
+                # widget here in the frontend
+                G.host.widgets.delete_widget(
+                    self.chat, all_instances=True, explicit_close=True)
+        else:
+            raise exceptions.InternalError("Unknown menu: {}".format(menu))
+
+
+class ExtraButton(SymbolButton):
+    chat = properties.ObjectProperty()
+
+
+class EncryptionMainButton(SymbolButton):
+
+    def __init__(self, chat, **kwargs):
+        """
+        @param chat(Chat): Chat instance
+        """
+        self.chat = chat
+        self.encryption_menu = EncryptionMenu(chat)
+        super(EncryptionMainButton, self).__init__(**kwargs)
+        self.bind(on_release=self.encryption_menu.open)
+
+    def select_algo(self, name):
+        """Mark an encryption algorithm as selected.
+
+        This will also deselect all other button
+        @param name(unicode, None): encryption plugin name
+            None for plain text
+        """
+        buttons = self.encryption_menu.container.children
+        buttons[-1].selected = name is None
+        for button in buttons[:-1]:
+            button.selected = button.text == name
+
+    def get_color(self):
+        if self.chat.otr_state_encryption == OTR_STATE_UNENCRYPTED:
+            return  (0.4, 0.4, 0.4, 1)
+        elif self.chat.otr_state_trust == OTR_STATE_TRUSTED:
+            return (0.29,0.87,0.0,1)
+        else:
+            return  (0.4, 0.4, 0.4, 1)
+
+    def get_symbol(self):
+        if self.chat.otr_state_encryption == OTR_STATE_UNENCRYPTED:
+            return 'lock-open'
+        elif self.chat.otr_state_trust == OTR_STATE_TRUSTED:
+            return 'lock-filled'
+        else:
+            return 'lock'
+
+
+class TrustManagementButton(SymbolButton):
+    pass
+
+
+class EncryptionButton(BoxLayout):
+    selected = properties.BooleanProperty(False)
+    text = properties.StringProperty()
+    trust_button = properties.BooleanProperty(False)
+    best_width = properties.NumericProperty(0)
+    bold = properties.BooleanProperty(True)
+
+    def __init__(self, **kwargs):
+        super(EncryptionButton, self).__init__(**kwargs)
+        self.register_event_type('on_release')
+        self.register_event_type('on_trust_release')
+        if self.trust_button:
+            self.add_widget(TrustManagementButton())
+
+    def on_release(self):
+        pass
+
+    def on_trust_release(self):
+        pass
+
+
+class EncryptionMenu(DropDown):
+    # best with to display all algorithms buttons + trust buttons
+    best_width = properties.NumericProperty(0)
+
+    def __init__(self, chat, **kwargs):
+        """
+        @param chat(Chat): Chat instance
+        """
+        self.chat = chat
+        super(EncryptionMenu, self).__init__(**kwargs)
+        btn = EncryptionButton(
+            text=_("unencrypted (plain text)"),
+            on_release=self.unencrypted,
+            selected=True,
+            bold=False,
+            )
+        btn.bind(
+            on_release=self.unencrypted,
+        )
+        self.add_widget(btn)
+        for plugin in G.host.encryption_plugins:
+            if chat.type == C.CHAT_GROUP and plugin["directed"]:
+                # directed plugins can't work with group chat
+                continue
+            btn = EncryptionButton(
+                text=plugin['name'],
+                trust_button=True,
+                )
+            btn.bind(
+                on_release=partial(self.start_encryption, plugin=plugin),
+                on_trust_release=partial(self.get_trust_ui, plugin=plugin),
+            )
+            self.add_widget(btn)
+            log.info("added encryption: {}".format(plugin['name']))
+
+    def message_encryption_stop_cb(self):
+        log.info(_("Session with {destinee} is now in plain text").format(
+            destinee = self.chat.target))
+
+    def message_encryption_stop_eb(self, failure_):
+        msg = _("Error while stopping encryption with {destinee}: {reason}").format(
+            destinee = self.chat.target,
+            reason = failure_)
+        log.warning(msg)
+        G.host.add_note(_("encryption problem"), msg, C.XMLUI_DATA_LVL_ERROR)
+
+    def unencrypted(self, button):
+        self.dismiss()
+        G.host.bridge.message_encryption_stop(
+            str(self.chat.target),
+            self.chat.profile,
+            callback=self.message_encryption_stop_cb,
+            errback=self.message_encryption_stop_eb)
+
+    def message_encryption_start_cb(self, plugin):
+        log.info(_("Session with {destinee} is now encrypted with {encr_name}").format(
+            destinee = self.chat.target,
+            encr_name = plugin['name']))
+
+    def message_encryption_start_eb(self, failure_):
+        msg = _("Session can't be encrypted with {destinee}: {reason}").format(
+            destinee = self.chat.target,
+            reason = failure_)
+        log.warning(msg)
+        G.host.add_note(_("encryption problem"), msg, C.XMLUI_DATA_LVL_ERROR)
+
+    def start_encryption(self, button, plugin):
+        """Request encryption with given plugin for this session
+
+        @param button(EncryptionButton): button which has been pressed
+        @param plugin(dict): plugin data
+        """
+        self.dismiss()
+        G.host.bridge.message_encryption_start(
+            str(self.chat.target),
+            plugin['namespace'],
+            True,
+            self.chat.profile,
+            callback=partial(self.message_encryption_start_cb, plugin=plugin),
+            errback=self.message_encryption_start_eb)
+
+    def encryption_trust_ui_get_cb(self, xmlui_raw):
+        xml_ui = xmlui.create(
+            G.host, xmlui_raw, profile=self.chat.profile)
+        xml_ui.show()
+
+    def encryption_trust_ui_get_eb(self, failure_):
+        msg = _("Trust manager interface can't be retrieved: {reason}").format(
+            reason = failure_)
+        log.warning(msg)
+        G.host.add_note(_("encryption trust management problem"), msg,
+                       C.XMLUI_DATA_LVL_ERROR)
+
+    def get_trust_ui(self, button, plugin):
+        """Request and display trust management UI
+
+        @param button(EncryptionButton): button which has been pressed
+        @param plugin(dict): plugin data
+        """
+        self.dismiss()
+        G.host.bridge.encryption_trust_ui_get(
+            str(self.chat.target),
+            plugin['namespace'],
+            self.chat.profile,
+            callback=self.encryption_trust_ui_get_cb,
+            errback=self.encryption_trust_ui_get_eb)
+
+
+class Chat(quick_chat.QuickChat, cagou_widget.LiberviaDesktopKivyWidget):
+    message_input = properties.ObjectProperty()
+    messages_widget = properties.ObjectProperty()
+    history_scroll = properties.ObjectProperty()
+    attachments_to_send = properties.ObjectProperty()
+    send_button_visible = properties.BooleanProperty()
+    use_header_input = True
+    global_screen_manager = True
+    collection_carousel = True
+
+    def __init__(self, host, target, type_=C.CHAT_ONE2ONE, nick=None, occupants=None,
+                 subject=None, statuses=None, profiles=None):
+        self.show_chat_selector = False
+        if statuses is None:
+            statuses = {}
+        quick_chat.QuickChat.__init__(
+            self, host, target, type_, nick, occupants, subject, statuses,
+            profiles=profiles)
+        self.otr_state_encryption = OTR_STATE_UNENCRYPTED
+        self.otr_state_trust = OTR_STATE_UNTRUSTED
+        # completion attributes
+        self._hi_comp_data = None
+        self._hi_comp_last = None
+        self._hi_comp_dropdown = DropDown()
+        self._hi_comp_allowed = True
+        cagou_widget.LiberviaDesktopKivyWidget.__init__(self)
+        transfer_btn = TransferButton(chat=self)
+        self.header_input_add_extra(transfer_btn)
+        if (type_ == C.CHAT_ONE2ONE or "REALJID_PUBLIC" in statuses):
+            self.encryption_btn = EncryptionMainButton(self)
+            self.header_input_add_extra(self.encryption_btn)
+        self.extra_menu = ExtraMenu(chat=self)
+        extra_btn = ExtraButton(chat=self)
+        self.header_input_add_extra(extra_btn)
+        self.header_input.hint_text = target
+        self._history_prepend_lock = False
+        self.history_count = 0
+
+    def on_kv_post(self, __):
+        self.post_init()
+
+    def screen_manager_init(self, screen_manager):
+        screen_manager.transition = screenmanager.SlideTransition(direction='down')
+        sel_screen = Screen(name='chat_selector')
+        chat_selector = ChatSelector(profile=self.profile)
+        sel_screen.add_widget(chat_selector)
+        screen_manager.add_widget(sel_screen)
+        if self.show_chat_selector:
+            transition = screen_manager.transition
+            screen_manager.transition = NoTransition()
+            screen_manager.current = 'chat_selector'
+            screen_manager.transition = transition
+
+    def __str__(self):
+        return "Chat({})".format(self.target)
+
+    def __repr__(self):
+        return self.__str__()
+
+    @classmethod
+    def factory(cls, plugin_info, target, profiles):
+        profiles = list(profiles)
+        if len(profiles) > 1:
+            raise NotImplementedError("Multi-profiles is not available yet for chat")
+        if target is None:
+            show_chat_selector = True
+            target = G.host.profiles[profiles[0]].whoami
+        else:
+            show_chat_selector = False
+        wid = G.host.widgets.get_or_create_widget(cls, target, on_new_widget=None,
+                                               on_existing_widget=G.host.get_or_clone,
+                                               profiles=profiles)
+        wid.show_chat_selector = show_chat_selector
+        return wid
+
+    @property
+    def message_widgets_rev(self):
+        return self.messages_widget.children
+
+    ## keyboard ##
+
+    def key_input(self, window, key, scancode, codepoint, modifier):
+        if key == 27:
+            screen_manager = self.screen_manager
+            screen_manager.transition.direction = 'down'
+            screen_manager.current = 'chat_selector'
+            return True
+
+    ## drop ##
+
+    def on_drop_file(self, path):
+        self.add_attachment(path)
+
+    ## header ##
+
+    def change_widget(self, jid_):
+        """change current widget for a new one with given jid
+
+        @param jid_(jid.JID): jid of the widget to create
+        """
+        plugin_info = G.host.get_plugin_info(main=Chat)
+        factory = plugin_info['factory']
+        G.host.switch_widget(self, factory(plugin_info, jid_, profiles=[self.profile]))
+        self.header_input.text = ''
+
+    def on_header_wid_input(self):
+        text = self.header_input.text.strip()
+        try:
+            if text.count('@') != 1 or text.count(' '):
+                raise ValueError
+            jid_ = jid.JID(text)
+        except ValueError:
+            log.info("entered text is not a jid")
+            return
+
+        def disco_cb(disco):
+            # TODO: check if plugin XEP-0045 is activated
+            if "conference" in [i[0] for i in disco[1]]:
+                G.host.bridge.muc_join(str(jid_), "", "", self.profile,
+                                      callback=self._muc_join_cb, errback=self._muc_join_eb)
+            else:
+                self.change_widget(jid_)
+
+        def disco_eb(failure):
+            log.warning("Disco failure, ignore this text: {}".format(failure))
+
+        G.host.bridge.disco_infos(
+            jid_.domain,
+            profile_key=self.profile,
+            callback=disco_cb,
+            errback=disco_eb)
+
+    def on_header_wid_input_completed(self, input_wid, completed_text):
+        self._hi_comp_allowed = False
+        input_wid.text = completed_text
+        self._hi_comp_allowed = True
+        self._hi_comp_dropdown.dismiss()
+        self.on_header_wid_input()
+
+    def on_header_wid_input_complete(self, wid, text):
+        if not self._hi_comp_allowed:
+            return
+        text = text.lstrip()
+        if not text:
+            self._hi_comp_data = None
+            self._hi_comp_last = None
+            self._hi_comp_dropdown.dismiss()
+            return
+
+        profile = list(self.profiles)[0]
+
+        if self._hi_comp_data is None:
+            # first completion, we build the initial list
+            comp_data = self._hi_comp_data = []
+            self._hi_comp_last = ''
+            for jid_, jid_data in G.host.contact_lists[profile].all_iter:
+                comp_data.append((jid_, jid_data))
+            comp_data.sort(key=lambda datum: datum[0])
+        else:
+            comp_data = self._hi_comp_data
+
+        # XXX: dropdown is rebuilt each time backspace is pressed or if the text is changed,
+        #      it works OK, but some optimisation may be done here
+        dropdown = self._hi_comp_dropdown
+
+        if not text.startswith(self._hi_comp_last) or not self._hi_comp_last:
+            # text has changed or backspace has been pressed, we restart
+            dropdown.clear_widgets()
+
+            for jid_, jid_data in comp_data:
+                nick = jid_data.get('nick', '')
+                if text in jid_.bare or text in nick.lower():
+                    btn = JidButton(
+                        jid = jid_.bare,
+                        profile = profile,
+                        size_hint = (0.5, None),
+                        nick = nick,
+                        on_release=lambda __, txt=jid_.bare: self.on_header_wid_input_completed(wid, txt)
+                        )
+                    dropdown.add_widget(btn)
+        else:
+            # more chars, we continue completion by removing unwanted widgets
+            to_remove = []
+            for c in dropdown.children[0].children:
+                if text not in c.jid and text not in (c.nick or ''):
+                    to_remove.append(c)
+            for c in to_remove:
+                dropdown.remove_widget(c)
+        if dropdown.attach_to is None:
+            dropdown.open(wid)
+        self._hi_comp_last = text
+
+    def message_data_converter(self, idx, mess_id):
+        return {"mess_data": self.messages[mess_id]}
+
+    def _on_history_printed(self):
+        """Refresh or scroll down the focus after the history is printed"""
+        # self.adapter.data = self.messages
+        for mess_data in self.messages.values():
+            self.appendMessage(mess_data)
+        super(Chat, self)._on_history_printed()
+
+    def create_message(self, message):
+        self.appendMessage(message)
+        # we need to render immediatly next 2 layouts to avoid an unpleasant flickering
+        # when sending or receiving a message
+        self.messages_widget.dont_delay_next_layouts = 2
+
+    def appendMessage(self, mess_data):
+        """Append a message Widget to the history
+
+        @param mess_data(quick_chat.Message): message data
+        """
+        if self.handle_user_moved(mess_data):
+            return
+        self.messages_widget.add_widget(MessageWidget(mess_data=mess_data))
+        self.notify(mess_data)
+
+    def prepend_message(self, mess_data):
+        """Prepend a message Widget to the history
+
+        @param mess_data(quick_chat.Message): message data
+        """
+        mess_wid = self.messages_widget
+        last_idx = len(mess_wid.children)
+        mess_wid.add_widget(MessageWidget(mess_data=mess_data), index=last_idx)
+
+    def _get_notif_msg(self, mess_data):
+        return _("{nick}: {message}").format(
+            nick=mess_data.nick,
+            message=mess_data.main_message)
+
+    def notify(self, mess_data):
+        """Notify user when suitable
+
+        For one2one chat, notification will happen when window has not focus
+        or when one2one chat is not visible. A note is also there when widget
+        is not visible.
+        For group chat, note will be added on mention, with a desktop notification if
+        window has not focus or is not visible.
+        """
+        visible_clones = [w for w in G.host.get_visible_list(self.__class__)
+                          if w.target == self.target]
+        if len(visible_clones) > 1 and visible_clones.index(self) > 0:
+            # to avoid multiple notifications in case of multiple cloned widgets
+            # we only handle first clone
+            return
+        is_visible = bool(visible_clones)
+        if self.type == C.CHAT_ONE2ONE:
+            if (not Window.focus or not is_visible) and not mess_data.history:
+                notif_msg = self._get_notif_msg(mess_data)
+                G.host.notify(
+                    type_=C.NOTIFY_MESSAGE,
+                    entity=mess_data.from_jid,
+                    message=notif_msg,
+                    subject=_("private message"),
+                    widget=self,
+                    profile=self.profile
+                )
+                if not is_visible:
+                    G.host.add_note(
+                        _("private message"),
+                        notif_msg,
+                        symbol = "chat",
+                        action = {
+                            "action": 'chat',
+                            "target": self.target,
+                            "profiles": self.profiles}
+                        )
+        else:
+            if mess_data.mention:
+                notif_msg = self._get_notif_msg(mess_data)
+                G.host.add_note(
+                    _("mention"),
+                    notif_msg,
+                    symbol = "chat",
+                    action = {
+                        "action": 'chat',
+                        "target": self.target,
+                        "profiles": self.profiles}
+                    )
+                if not is_visible or not Window.focus:
+                    subject=_("mention ({room_jid})").format(room_jid=self.target)
+                    G.host.notify(
+                        type_=C.NOTIFY_MENTION,
+                        entity=self.target,
+                        message=notif_msg,
+                        subject=subject,
+                        widget=self,
+                        profile=self.profile
+                    )
+
+    # message input
+
+    def _attachment_progress_cb(self, item, metadata, profile):
+        item.parent.remove_widget(item)
+        log.info(f"item {item.data.get('path')} uploaded successfully")
+
+    def _attachment_progress_eb(self, item, err_msg, profile):
+        item.parent.remove_widget(item)
+        path = item.data.get('path')
+        msg = _("item {path} could not be uploaded: {err_msg}").format(
+            path=path, err_msg=err_msg)
+        G.host.add_note(_("can't upload file"), msg, C.XMLUI_DATA_LVL_WARNING)
+        log.warning(msg)
+
+    def _progress_get_cb(self, item, metadata):
+        try:
+            position = int(metadata["position"])
+            size = int(metadata["size"])
+        except KeyError:
+            # we got empty metadata, the progression is either not yet started or
+            # finished
+            if item.progress:
+                # if progress is already started, receiving empty metadata means
+                # that progression is finished
+                item.progress = 100
+                return
+        else:
+            item.progress = position/size*100
+
+        if item.parent is not None:
+            # the item is not yet fully received, we reschedule an update
+            Clock.schedule_once(
+                partial(self._attachment_progress_update, item),
+                PROGRESS_UPDATE)
+
+    def _attachment_progress_update(self, item, __):
+        G.host.bridge.progress_get(
+            item.data["progress_id"],
+            self.profile,
+            callback=partial(self._progress_get_cb, item),
+            errback=G.host.errback,
+        )
+
+    def add_nick(self, nick):
+        """Add a nickname to message_input if suitable"""
+        if (self.type == C.CHAT_GROUP and not self.message_input.text.startswith(nick)):
+            self.message_input.text = f'{nick}: {self.message_input.text}'
+
+    def on_send(self, input_widget):
+        extra = {}
+        for item in self.attachments_to_send.attachments.children:
+            if item.sending:
+                # the item is already being sent
+                continue
+            item.sending = True
+            progress_id = item.data["progress_id"] = str(uuid.uuid4())
+            attachments = extra.setdefault(C.KEY_ATTACHMENTS, [])
+            attachment = {
+                "path": str(item.data["path"]),
+                "progress_id": progress_id,
+            }
+            if 'media_type' in item.data:
+                attachment[C.KEY_ATTACHMENTS_MEDIA_TYPE] = item.data['media_type']
+
+            if ((self.attachments_to_send.reduce_checkbox.active
+                 and attachment.get('media_type', '').split('/')[0] == 'image')):
+                attachment[C.KEY_ATTACHMENTS_RESIZE] = True
+
+            attachments.append(attachment)
+
+            Clock.schedule_once(
+                partial(self._attachment_progress_update, item),
+                PROGRESS_UPDATE)
+
+            G.host.register_progress_cbs(
+                progress_id,
+                callback=partial(self._attachment_progress_cb, item),
+                errback=partial(self._attachment_progress_eb, item)
+            )
+
+
+        G.host.message_send(
+            self.target,
+            # TODO: handle language
+            {'': input_widget.text},
+            # TODO: put this in QuickChat
+            mess_type=
+                C.MESS_TYPE_GROUPCHAT if self.type == C.CHAT_GROUP else C.MESS_TYPE_CHAT,
+            extra=extra,
+            profile_key=self.profile
+            )
+        input_widget.text = ''
+
+    def _image_check_cb(self, report_raw):
+        report = data_format.deserialise(report_raw)
+        if report['too_large']:
+            self.attachments_to_send.show_resize=True
+            self.attachments_to_send.reduce_checkbox.active=True
+
+    def add_attachment(self, file_path, media_type=None):
+        file_path = Path(file_path)
+        if media_type is None:
+            media_type = mimetypes.guess_type(str(file_path), strict=False)[0]
+        if not self.attachments_to_send.show_resize and media_type is not None:
+            # we check if the attachment is an image and if it's too large.
+            # If too large, the reduce size check box will be displayed, and checked by
+            # default.
+            main_type = media_type.split('/')[0]
+            if main_type == "image":
+                G.host.bridge.image_check(
+                    str(file_path),
+                    callback=self._image_check_cb,
+                    errback=partial(
+                        G.host.errback,
+                        title=_("Can't check image size"),
+                        message=_("Can't check image at {path}: {{msg}}").format(
+                            path=file_path),
+                    )
+                )
+
+        data = {
+            "path": file_path,
+            "name": file_path.name,
+        }
+
+        if media_type is not None:
+            data['media_type'] = media_type
+
+        self.attachments_to_send.attachments.add_widget(
+            AttachmentToSendItem(data=data)
+        )
+
+    def transfer_file(self, file_path, transfer_type=C.TRANSFER_UPLOAD, cleaning_cb=None):
+        # FIXME: cleaning_cb is not managed
+        if transfer_type == C.TRANSFER_UPLOAD:
+            self.add_attachment(file_path)
+        elif transfer_type == C.TRANSFER_SEND:
+            if self.type == C.CHAT_GROUP:
+                log.warning("P2P transfer is not possible for group chat")
+                # TODO: show an error dialog to user, or better hide the send button for
+                #       MUC
+            else:
+                jid_ = self.target
+                if not jid_.resource:
+                    jid_ = G.host.contact_lists[self.profile].get_full_jid(jid_)
+                G.host.bridge.file_send(str(jid_), str(file_path), "", "", "",
+                                       profile=self.profile)
+                # TODO: notification of sending/failing
+        else:
+            raise log.error("transfer of type {} are not handled".format(transfer_type))
+
+    def message_encryption_started(self, plugin_data):
+        quick_chat.QuickChat.message_encryption_started(self, plugin_data)
+        self.encryption_btn.symbol = SYMBOL_ENCRYPTED
+        self.encryption_btn.color = COLOR_ENCRYPTED
+        self.encryption_btn.select_algo(plugin_data['name'])
+
+    def message_encryption_stopped(self, plugin_data):
+        quick_chat.QuickChat.message_encryption_stopped(self, plugin_data)
+        self.encryption_btn.symbol = SYMBOL_UNENCRYPTED
+        self.encryption_btn.color = COLOR_UNENCRYPTED
+        self.encryption_btn.select_algo(None)
+
+    def _muc_join_cb(self, joined_data):
+        joined, room_jid_s, occupants, user_nick, subject, statuses, profile = joined_data
+        self.host.muc_room_joined_handler(*joined_data[1:])
+        jid_ = jid.JID(room_jid_s)
+        self.change_widget(jid_)
+
+    def _muc_join_eb(self, failure):
+        log.warning("Can't join room: {}".format(failure))
+
+    def on_otr_state(self, state, dest_jid, profile):
+        assert profile in self.profiles
+        if state in OTR_STATE_ENCRYPTION:
+            self.otr_state_encryption = state
+        elif state in OTR_STATE_TRUST:
+            self.otr_state_trust = state
+        else:
+            log.error(_("Unknown OTR state received: {}".format(state)))
+            return
+        self.encryption_btn.symbol = self.encryption_btn.get_symbol()
+        self.encryption_btn.color = self.encryption_btn.get_color()
+
+    def on_visible(self):
+        if not self.sync:
+            self.resync()
+
+    def on_selected(self):
+        G.host.clear_notifs(self.target, profile=self.profile)
+
+    def on_delete(self, **kwargs):
+        if kwargs.get('explicit_close', False):
+            wrapper = self.whwrapper
+            if wrapper is not None:
+                if len(wrapper.carousel.slides) == 1:
+                    # if we delete the last opened chat, we need to show the selector
+                    screen_manager = self.screen_manager
+                    screen_manager.transition.direction = 'down'
+                    screen_manager.current = 'chat_selector'
+                wrapper.carousel.remove_widget(self)
+            return True
+        # we always keep one widget, so it's available when swiping
+        # TODO: delete all widgets when chat is closed
+        nb_instances = sum(1 for _ in self.host.widgets.get_widget_instances(self))
+        # we want to keep at least one instance of Chat by WHWrapper
+        nb_to_keep = len(G.host.widgets_handler.children)
+        if nb_instances <= nb_to_keep:
+            return False
+
+    def _history_unlock(self, __):
+        self._history_prepend_lock = False
+        log.debug("history prepend unlocked")
+        # we call manually on_scroll, to check if we are still in the scrolling zone
+        self.on_scroll(self.history_scroll, self.history_scroll.scroll_y)
+
+    def _history_scroll_adjust(self, __, scroll_start_height):
+        # history scroll position must correspond to where it was before new messages
+        # have been appended
+        self.history_scroll.scroll_y = (
+            scroll_start_height / self.messages_widget.height
+        )
+
+        # we want a small delay before unlocking, to avoid re-fetching history
+        # again
+        Clock.schedule_once(self._history_unlock, 1.5)
+
+    def _back_history_get_cb_post(self, __, history, scroll_start_height):
+        if len(history) == 0:
+            # we don't unlock self._history_prepend_lock if there is no history, as there
+            # is no sense to try to retrieve more in this case.
+            log.debug(f"we've reached top of history for {self.target.bare} chat")
+        else:
+            # we have to schedule again for _history_scroll_adjust, else messages_widget
+            # is not resized (self.messages_widget.height is not yet updated)
+            # as a result, the scroll_to can't work correctly
+            Clock.schedule_once(partial(
+                self._history_scroll_adjust,
+                scroll_start_height=scroll_start_height))
+            log.debug(
+                f"{len(history)} messages prepended to history (last: {history[0][0]})")
+
+    def _back_history_get_cb(self, history):
+        # TODO: factorise with QuickChat._history_get_cb
+        scroll_start_height = self.messages_widget.height * self.history_scroll.scroll_y
+        for data in reversed(history):
+            uid, timestamp, from_jid, to_jid, message, subject, type_, extra_s = data
+            from_jid = jid.JID(from_jid)
+            to_jid = jid.JID(to_jid)
+            extra = data_format.deserialise(extra_s)
+            extra["history"] = True
+            self.messages[uid] = message = quick_chat.Message(
+                self,
+                uid,
+                timestamp,
+                from_jid,
+                to_jid,
+                message,
+                subject,
+                type_,
+                extra,
+                self.profile,
+            )
+            self.messages.move_to_end(uid, last=False)
+            self.prepend_message(message)
+        Clock.schedule_once(partial(
+            self._back_history_get_cb_post,
+            history=history,
+            scroll_start_height=scroll_start_height))
+
+    def _back_history_get_eb(self, failure_):
+        G.host.add_note(
+            _("Problem while getting back history"),
+            _("Can't back history for {target}: {problem}").format(
+                target=self.target, problem=failure_),
+            C.XMLUI_DATA_LVL_ERROR)
+        # we don't unlock self._history_prepend_lock on purpose, no need
+        # to try to get more history if something is wrong
+
+    def on_scroll(self, scroll_view, scroll_y):
+        if self._history_prepend_lock:
+            return
+        if (1-scroll_y) * self.messages_widget.height < INFINITE_SCROLL_LIMIT:
+            self._history_prepend_lock = True
+            log.debug(f"Retrieving back history for {self} [{self.history_count}]")
+            self.history_count += 1
+            first_uid = next(iter(self.messages.keys()))
+            filters = self.history_filters.copy()
+            filters['before_uid'] = first_uid
+            self.host.bridge.history_get(
+                str(self.host.profiles[self.profile].whoami.bare),
+                str(self.target),
+                30,
+                True,
+                {k: str(v) for k,v in filters.items()},
+                self.profile,
+                callback=self._back_history_get_cb,
+                errback=self._back_history_get_eb,
+            )
+
+
+class ChatSelector(cagou_widget.LiberviaDesktopKivyWidget, FilterBehavior):
+    jid_selector = properties.ObjectProperty()
+    profile = properties.StringProperty()
+    plugin_info_class = Chat
+    use_header_input = True
+
+    def on_select(self, contact_button):
+        contact_jid = jid.JID(contact_button.jid)
+        plugin_info = G.host.get_plugin_info(main=Chat)
+        factory = plugin_info['factory']
+        self.screen_manager.transition.direction = 'up'
+        carousel = self.whwrapper.carousel
+        current_slides = {w.target: w for w in carousel.slides}
+        if contact_jid in current_slides:
+            slide = current_slides[contact_jid]
+            idx = carousel.slides.index(slide)
+            carousel.index = idx
+            self.screen_manager.current = ''
+        else:
+            G.host.switch_widget(
+                self, factory(plugin_info, contact_jid, profiles=[self.profile]))
+
+
+    def on_header_wid_input(self):
+        text = self.header_input.text.strip()
+        try:
+            if text.count('@') != 1 or text.count(' '):
+                raise ValueError
+            jid_ = jid.JID(text)
+        except ValueError:
+            log.info("entered text is not a jid")
+            return
+        G.host.do_action("chat", jid_, [self.profile])
+
+    def on_header_wid_input_complete(self, wid, text, **kwargs):
+        """we filter items when text is entered in input box"""
+        for layout in self.jid_selector.items_layouts:
+            self.do_filter(
+                layout,
+                text,
+                # we append nick to jid to filter on both
+                lambda c: c.jid + c.data.get('nick', ''),
+                width_cb=lambda c: c.base_width,
+                height_cb=lambda c: c.minimum_height,
+                continue_tests=[lambda c: not isinstance(c, ContactButton)])
+
+
+PLUGIN_INFO["factory"] = Chat.factory
+quick_widgets.register(quick_chat.QuickChat, Chat)