diff libervia/frontends/quick_frontend/quick_widgets.py @ 4074:26b7ed2817da

refactoring: rename `sat_frontends` to `libervia.frontends`
author Goffi <goffi@goffi.org>
date Fri, 02 Jun 2023 14:12:38 +0200 (19 months ago)
parents sat_frontends/quick_frontend/quick_widgets.py@4b842c1fb686
children 0d7bb4df2343
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/frontends/quick_frontend/quick_widgets.py	Fri Jun 02 14:12:38 2023 +0200
@@ -0,0 +1,478 @@
+#!/usr/bin/env python3
+
+
+# helper class for making a SAT frontend
+# Copyright (C) 2009-2021 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 libervia.backend.core.log import getLogger
+
+log = getLogger(__name__)
+from libervia.backend.core import exceptions
+from libervia.frontends.quick_frontend.constants import Const as C
+
+
+classes_map = {}
+
+
+try:
+    # FIXME: to be removed when an acceptable solution is here
+    str("")  # XXX: unicode doesn't exist in pyjamas
+except (
+    TypeError,
+    AttributeError,
+):  # Error raised is not the same depending on pyjsbuild options
+    str = str
+
+
+def register(base_cls, child_cls=None):
+    """Register a child class to use by default when a base class is needed
+
+    @param base_cls: "Quick..." base class (like QuickChat or QuickContact), must inherit from QuickWidget
+    @param child_cls: inherited class to use when Quick... class is requested, must inherit from base_cls.
+        Can be None if it's the base_cls itself which register
+    """
+    # FIXME: we use base_cls.__name__ instead of base_cls directly because pyjamas because
+    #        in the second case
+    classes_map[base_cls.__name__] = child_cls
+
+
+class WidgetAlreadyExistsError(Exception):
+    pass
+
+
+class QuickWidgetsManager(object):
+    """This class is used to manage all the widgets of a frontend
+    A widget can be a window, a graphical thing, or someting else depending of the frontend"""
+
+    def __init__(self, host):
+        self.host = host
+        self._widgets = {}
+
+    def __iter__(self):
+        """Iterate throught all widgets"""
+        for widget_map in self._widgets.values():
+            for widget_instances in widget_map.values():
+                for widget in widget_instances:
+                    yield widget
+
+    def get_real_class(self, class_):
+        """Return class registered for given class_
+
+        @param class_: subclass of QuickWidget
+        @return: class actually used to create widget
+        """
+        try:
+            # FIXME: we use base_cls.__name__ instead of base_cls directly because pyjamas bugs
+            #        in the second case
+            cls = classes_map[class_.__name__]
+        except KeyError:
+            cls = class_
+        if cls is None:
+            raise exceptions.InternalError(
+                "There is not class registered for {}".format(class_)
+            )
+        return cls
+
+    def get_widget_instances(self, widget):
+        """Get all instance of a widget
+
+        This is a helper method which call get_widgets
+        @param widget(QuickWidget): retrieve instances of this widget
+        @return: iterator on widgets
+        """
+        return self.get_widgets(widget.__class__, widget.target, widget.profiles)
+
+    def get_widgets(self, class_, target=None, profiles=None, with_duplicates=True):
+        """Get all subclassed widgets instances
+
+        @param class_: subclass of QuickWidget, same parameter as used in
+            [get_or_create_widget]
+        @param target: if not None, construct a hash with this target and filter
+            corresponding widgets
+            recreated widgets are handled
+        @param profiles(iterable, None): if not None, filter on instances linked to these
+            profiles
+        @param with_duplicates(bool): if False, only first widget with a given hash is
+            returned
+        @return: iterator on widgets
+        """
+        class_ = self.get_real_class(class_)
+        try:
+            widgets_map = self._widgets[class_.__name__]
+        except KeyError:
+            return
+        else:
+            if target is not None:
+                filter_hash = str(class_.get_widget_hash(target, profiles))
+            else:
+                filter_hash = None
+            if filter_hash is not None:
+                for widget in widgets_map.get(filter_hash, []):
+                    yield widget
+                    if not with_duplicates:
+                        return
+            else:
+                for widget_instances in widgets_map.values():
+                    for widget in widget_instances:
+                        yield widget
+                        if not with_duplicates:
+                            # widgets are set by hashes, so if don't want duplicates
+                            # we only return the first widget of the list
+                            break
+
+    def get_widget(self, class_, target=None, profiles=None):
+        """Get a widget without creating it if it doesn't exist.
+
+        if several instances of widgets with this hash exist, the first one is returned
+        @param class_: subclass of QuickWidget, same parameter as used in [get_or_create_widget]
+        @param target: target depending of the widget, usually a JID instance
+        @param profiles (unicode, iterable[unicode], None): profile(s) to use (may or may not be
+            used, depending of the widget class)
+        @return: a class_ instance or None if the widget doesn't exist
+        """
+        assert (target is not None) or (profiles is not None)
+        if profiles is not None and isinstance(profiles, str):
+            profiles = [profiles]
+        class_ = self.get_real_class(class_)
+        hash_ = class_.get_widget_hash(target, profiles)
+        try:
+            return self._widgets[class_.__name__][hash_][0]
+        except KeyError:
+            return None
+
+    def get_or_create_widget(self, class_, target, *args, **kwargs):
+        """Get an existing widget or create a new one when necessary
+
+        If the widget is new, self.host.new_widget will be called with it.
+        @param class_(class): class of the widget to create
+        @param target: target depending of the widget, usually a JID instance
+        @param args(list): optional args to create a new instance of class_
+        @param kwargs(dict): optional kwargs to create a new instance of class_
+            if 'profile' key is present, it will be popped and put in 'profiles'
+            if there is neither 'profile' nor 'profiles', None will be used for 'profiles'
+            if 'on_new_widget' is present it can have the following values:
+                C.WIDGET_NEW [default]: self.host.new_widget will be called on widget creation
+                [callable]: this method will be called instead of self.host.new_widget
+                None: do nothing
+            if 'on_existing_widget' is present it can have the following values:
+                C.WIDGET_KEEP  [default]: return the existing widget
+                C.WIDGET_RAISE: raise WidgetAlreadyExistsError
+                C.WIDGET_RECREATE: create a new widget
+                    if the existing widget has a "recreate_args" method, it will be called with args list and kwargs dict
+                    so the values can be completed to create correctly the new instance
+                [callable]: this method will be called with existing widget as argument, the widget to use must be returned
+            if 'force_hash' is present, the hash given in value will be used instead of the one returned by class_.get_widget_hash
+            other keys will be used to instanciate class_ if the case happen (e.g. if type_ is present and class_ is a QuickChat subclass,
+                it will be used to create a new QuickChat instance).
+        @return: a class_ instance, either new or already existing
+        """
+        cls = self.get_real_class(class_)
+
+        ## arguments management ##
+        _args = [self.host, target] + list(
+            args
+        ) or []  # FIXME: check if it's really necessary to use optional args
+        _kwargs = kwargs or {}
+        if "profiles" in _kwargs and "profile" in _kwargs:
+            raise ValueError(
+                "You can't have 'profile' and 'profiles' keys at the same time"
+            )
+        try:
+            _kwargs["profiles"] = [_kwargs.pop("profile")]
+        except KeyError:
+            if not "profiles" in _kwargs:
+                _kwargs["profiles"] = None
+
+        # on_new_widget tells what to do for the new widget creation
+        try:
+            on_new_widget = _kwargs.pop("on_new_widget")
+        except KeyError:
+            on_new_widget = C.WIDGET_NEW
+
+        # on_existing_widget tells what to do when the widget already exists
+        try:
+            on_existing_widget = _kwargs.pop("on_existing_widget")
+        except KeyError:
+            on_existing_widget = C.WIDGET_KEEP
+
+        ## we get the hash ##
+        try:
+            hash_ = _kwargs.pop("force_hash")
+        except KeyError:
+            hash_ = cls.get_widget_hash(target, _kwargs["profiles"])
+
+        ## widget creation or retrieval ##
+
+        widgets_map = self._widgets.setdefault(
+            cls.__name__, {}
+        )  # we sorts widgets by classes
+        if not cls.SINGLE:
+            widget = None  # if the class is not SINGLE, we always create a new widget
+        else:
+            try:
+                widget = widgets_map[hash_][0]
+            except KeyError:
+                widget = None
+            else:
+                widget.add_target(target)
+
+        if widget is None:
+            # we need to create a new widget
+            log.debug(f"Creating new widget for target {target} {cls}")
+            widget = cls(*_args, **_kwargs)
+            widgets_map.setdefault(hash_, []).append(widget)
+            self.host.call_listeners("widgetNew", widget)
+
+            if on_new_widget == C.WIDGET_NEW:
+                self.host.new_widget(widget)
+            elif callable(on_new_widget):
+                on_new_widget(widget)
+            else:
+                assert on_new_widget is None
+        else:
+            # the widget already exists
+            if on_existing_widget == C.WIDGET_KEEP:
+                pass
+            elif on_existing_widget == C.WIDGET_RAISE:
+                raise WidgetAlreadyExistsError(hash_)
+            elif on_existing_widget == C.WIDGET_RECREATE:
+                try:
+                    recreate_args = widget.recreate_args
+                except AttributeError:
+                    pass
+                else:
+                    recreate_args(_args, _kwargs)
+                widget = cls(*_args, **_kwargs)
+                widgets_map[hash_].append(widget)
+                log.debug("widget <{wid}> already exists, a new one has been recreated"
+                    .format(wid=widget))
+            elif callable(on_existing_widget):
+                widget = on_existing_widget(widget)
+                if widget is None:
+                    raise exceptions.InternalError(
+                        "on_existing_widget method must return the widget to use")
+                if widget not in widgets_map[hash_]:
+                    log.debug(
+                        "the widget returned by on_existing_widget is new, adding it")
+                    widgets_map[hash_].append(widget)
+            else:
+                raise exceptions.InternalError(
+                    "Unexpected on_existing_widget value ({})".format(on_existing_widget))
+
+        return widget
+
+    def delete_widget(self, widget_to_delete, *args, **kwargs):
+        """Delete a widget instance
+
+        this method must be called by frontends when a widget is deleted
+        widget's on_delete method will be called before deletion, and deletion will be
+        stopped if it returns False.
+        @param widget_to_delete(QuickWidget): widget which need to deleted
+        @param *args: extra arguments to pass to on_delete
+        @param *kwargs: extra keywords arguments to pass to on_delete
+            the extra arguments are not used by QuickFrontend, it's is up to
+            the frontend to use them or not.
+            following extra arguments are well known:
+                - "all_instances" can be used as kwarg, if it evaluate to True,
+                  all instances of the widget will be deleted (if on_delete is
+                  not returning False for any of the instance). This arguments
+                  is not sent to on_delete methods.
+                - "explicit_close" is used when the deletion is requested by
+                  the user or a leave signal, "all_instances" is usually set at
+                  the same time.
+        """
+        # TODO: all_instances must be independante kwargs, this is not possible with Python 2
+        #       but will be with Python 3
+        all_instances = kwargs.get('all_instances', False)
+
+        if all_instances:
+            for w in self.get_widget_instances(widget_to_delete):
+                if w.on_delete(**kwargs) == False:
+                    log.debug(
+                        f"Deletion of {widget_to_delete} cancelled by widget itself")
+                    return
+        else:
+            if widget_to_delete.on_delete(**kwargs) == False:
+                log.debug(f"Deletion of {widget_to_delete} cancelled by widget itself")
+                return
+
+        if self.host.selected_widget == widget_to_delete:
+            self.host.selected_widget = None
+
+        class_ = self.get_real_class(widget_to_delete.__class__)
+        try:
+            widgets_map = self._widgets[class_.__name__]
+        except KeyError:
+            log.error("no widgets_map found for class {cls}".format(cls=class_))
+            return
+        widget_hash = str(class_.get_widget_hash(widget_to_delete.target,
+                                                   widget_to_delete.profiles))
+        try:
+            widget_instances = widgets_map[widget_hash]
+        except KeyError:
+            log.error(f"no instance of {class_.__name__} found with hash {widget_hash!r}")
+            return
+        if all_instances:
+            widget_instances.clear()
+        else:
+            try:
+                widget_instances.remove(widget_to_delete)
+            except ValueError:
+                log.error("widget_to_delete not found in widget instances")
+                return
+
+            log.debug("widget {} deleted".format(widget_to_delete))
+
+        if not widget_instances:
+            # all instances with this hash have been deleted
+            # we remove the hash itself
+            del widgets_map[widget_hash]
+            log.debug("All instances of {cls} with hash {widget_hash!r} have been deleted"
+                .format(cls=class_, widget_hash=widget_hash))
+            self.host.call_listeners("widgetDeleted", widget_to_delete)
+
+
+class QuickWidget(object):
+    """generic widget base"""
+    # FIXME: sometime a single target is used, sometimes several ones
+    #        This should be sorted out in the same way as for profiles: a single
+    #        target should be possible when appropriate attribute is set.
+    #        methods using target(s) and hash should be fixed accordingly
+
+    SINGLE = True  # if True, there can be only one widget per target(s)
+    PROFILES_MULTIPLE = False  # If True, this widget can handle several profiles at once
+    PROFILES_ALLOW_NONE = False  # If True, this widget can be used without profile
+
+    def __init__(self, host, target, profiles=None):
+        """
+        @param host: %(doc_host)s
+        @param target: target specific for this widget class
+        @param profiles: can be either:
+            - (unicode): used when widget class manage a unique profile
+            - (iterable): some widget class can manage several profiles, several at once can be specified here
+            - None: no profile is managed by this widget class (rare)
+        @raise: ValueError when (iterable) or None is given to profiles for a widget class which manage one unique profile.
+        """
+        self.host = host
+        self.targets = set()
+        self.add_target(target)
+        self.profiles = set()
+        self._sync = True
+        if isinstance(profiles, str):
+            self.add_profile(profiles)
+        elif profiles is None:
+            if not self.PROFILES_ALLOW_NONE:
+                raise ValueError("profiles can't have a value of None")
+        else:
+            for profile in profiles:
+                self.add_profile(profile)
+            if not self.profiles:
+                raise ValueError("no profile found, use None for no profile classes")
+
+    @property
+    def profile(self):
+        assert (
+            len(self.profiles) == 1
+            and not self.PROFILES_MULTIPLE
+            and not self.PROFILES_ALLOW_NONE
+        )
+        return list(self.profiles)[0]
+
+    @property
+    def target(self):
+        """Return main target
+
+        A random target is returned when several targets are available
+        """
+        return next(iter(self.targets))
+
+    @property
+    def widget_hash(self):
+        """Return quick widget hash"""
+        return self.get_widget_hash(self.target, self.profiles)
+
+    # synchronisation state
+
+    @property
+    def sync(self):
+        return self._sync
+
+    @sync.setter
+    def sync(self, state):
+        """state of synchronisation with backend
+
+        @param state(bool): True when backend is synchronised
+            False is set by core
+            True must be set by the widget when resynchronisation is finished
+        """
+        self._sync = state
+
+    def resync(self):
+        """Method called when backend can be resynchronized
+
+        The widget has to set self.sync itself when the synchronisation is finished
+        """
+        pass
+
+    # target/profile
+
+    def add_target(self, target):
+        """Add a target if it doesn't already exists
+
+        @param target: target to add
+        """
+        self.targets.add(target)
+
+    def add_profile(self, profile):
+        """Add a profile is if doesn't already exists
+
+        @param profile: profile to add
+        """
+        if self.profiles and not self.PROFILES_MULTIPLE:
+            raise ValueError("multiple profiles are not allowed")
+        self.profiles.add(profile)
+
+    # widget identitication
+
+    @staticmethod
+    def get_widget_hash(target, profiles):
+        """Return the hash associated with this target for this widget class
+
+        some widget classes can manage several target on the same instance
+        (e.g.: a chat widget with multiple resources on the same bare jid),
+        this method allow to return a hash associated to one or several targets
+        to retrieve the good instance. For example, a widget managing JID targets,
+        and all resource of the same bare jid would return the bare jid as hash.
+
+        @param target: target to check
+        @param profiles: profile(s) associated to target, see __init__ docstring
+        @return: a hash (can correspond to one or many targets or profiles, depending of widget class)
+        """
+        return str(target)  # by defaut, there is one hash for one target
+
+    # widget life events
+
+    def on_delete(self, *args, **kwargs):
+        """Called when a widget is being deleted
+
+        @return (boot, None): False to cancel deletion
+            all other value continue deletion
+        """
+        return True
+
+    def on_selected(self):
+        """Called when host.selected_widget is this instance"""
+        pass