sugar-toolkit-gtk3/shell/view/frame/clipboardbox.py

# Copyright (C) 2007, One Laptop Per Child
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

import os
import logging

import hippo
import gtk
 
from sugar import util
from view.clipboardicon import ClipboardIcon
from sugar.clipboard import clipboardservice

class _ContextMap:
    """Maps a drag context to the clipboard object involved in the dragging."""
    def __init__(self):
        self._context_map = {}
        
    def add_context(self, context, object_id, data_types):
        """Establishes the mapping. data_types will serve us for reference-
        counting this mapping.
        """
        self._context_map[context] = [object_id, data_types]
    
    def get_object_id(self, context):
        """Retrieves the object_id associated with context.
        Will release the association when this function was called as many times
        as the number of data_types that this clipboard object contains.
        """
        [object_id, data_types_left] = self._context_map[context]
        
        data_types_left = data_types_left - 1
        if data_types_left == 0:
            del self._context_map[context]
        else:
            self._context_map[context] = [object_id, data_types_left]

        return object_id

    def has_context(self, context):
        return context in self._context_map
 
class ClipboardBox(hippo.CanvasBox):
    
    def __init__(self):
        hippo.CanvasBox.__init__(self)
        self._icons = {}
        self._context_map = _ContextMap()
        self._selected_icon = None
        self._owns_clipboard = False

        self._pressed_button = None
        self._press_start_x = None
        self._press_start_y = None

        cb_service = clipboardservice.get_instance()
        cb_service.connect('object-added', self._object_added_cb)
        cb_service.connect('object-deleted', self._object_deleted_cb)
        cb_service.connect('object-state-changed', self._object_state_changed_cb)

    def owns_clipboard(self):
        return self._owns_clipboard

    def _get_icon_at_coords(self, x, y):
        box_x, box_y = self.get_context().translate_to_widget(self)
        x -= box_x
        y -= box_y
        for object_id, icon in self._icons.iteritems():
            icon_x, icon_y = self.get_position(icon)
            icon_width, icon_height = icon.get_allocation()

            if (x >= icon_x ) and (x <= icon_x + icon_width) and        \
                    (y >= icon_y ) and (y <= icon_y + icon_height):
                return icon
                
        return None

    def _add_selection(self, object_id, selection):
        if not selection.data:
            return

        logging.debug('ClipboardBox: adding type ' + selection.type)

        cb_service = clipboardservice.get_instance()
        if selection.type == 'text/uri-list':
            uris = selection.data.split('\n')
            if len(uris) > 1:
                raise NotImplementedError('Multiple uris in text/uri-list still not supported.')

            cb_service.add_object_format(object_id, 
                                         selection.type,
                                         uris[0],
                                         on_disk=True)
        else:
            cb_service.add_object_format(object_id, 
                                         selection.type,
                                         selection.data,
                                         on_disk=False)
    
    def _object_added_cb(self, cb_service, object_id, name):
        icon = ClipboardIcon(object_id, name)
        icon.connect('button-release-event', self._icon_button_release_event_cb)
        self._set_icon_selected(icon)

        self.prepend(icon)
        self._icons[object_id] = icon
        
        logging.debug('ClipboardBox: ' + object_id + ' was added.')

    def _set_icon_selected(self, icon):
        logging.debug('_set_icon_selected')
        icon.props.selected = True
        if self._selected_icon:
            self._selected_icon.props.selected = False
        self._selected_icon = icon

    def _put_in_clipboard(self, object_id):
        logging.debug('ClipboardBox._put_in_clipboard')
        targets = self._get_object_targets(object_id)
        if targets:
            clipboard = gtk.Clipboard()
            if not clipboard.set_with_data(targets,
                                           self._clipboard_data_get_cb,
                                           self._clipboard_clear_cb,
                                           targets):
                logging.error('GtkClipboard.set_with_data failed!')
            else:
                self._owns_clipboard = True

    def _clipboard_data_get_cb(self, clipboard, selection, info, targets):
        if not selection.target in [target[0] for target in targets]:
            logging.warning('ClipboardBox._clipboard_data_get_cb: asked %s but' \
                            ' only have %r.' % (selection.target, targets))
            return
        object_id = self._selected_icon.get_object_id()
        cb_service = clipboardservice.get_instance()
        data = cb_service.get_object_data(object_id, selection.target)['DATA']
        
        selection.set(selection.target, 8, data)

    def _clipboard_clear_cb(self, clipboard, targets):
        logging.debug('ClipboardBox._clipboard_clear_cb')
        self._owns_clipboard = False

    def _icon_button_release_event_cb(self, icon, event):
        logging.debug('ClipboardBox._icon_button_release_event_cb: %r' % icon.props.selected)
        if not icon.props.selected:
            self._set_icon_selected(icon)

    def _object_deleted_cb(self, cb_service, object_id):
        icon = self._icons[object_id]
        position = self.get_children().index(icon)
        self.remove(icon)
        
        if icon.props.selected and self.get_children():
            self._set_icon_selected(self.get_children()[position])

        del self._icons[object_id]
        logging.debug('ClipboardBox: ' + object_id + ' was deleted.')

    def _object_state_changed_cb(self, cb_service, object_id, name, percent,
                                 icon_name, preview, activity):
        icon = self._icons[object_id]
        icon.set_state(name, percent, icon_name, preview, activity)
        if icon.props.selected and percent == 100:
            self._put_in_clipboard(object_id)

    def drag_motion_cb(self, widget, context, x, y, time):
        logging.debug('ClipboardBox._drag_motion_cb')
        context.drag_status(gtk.gdk.ACTION_COPY, time)
        return True;

    def drag_drop_cb(self, widget, context, x, y, time):
        logging.debug('ClipboardBox._drag_drop_cb')
        cb_service = clipboardservice.get_instance()
        object_id = cb_service.add_object(name="")

        self._context_map.add_context(context, object_id, len(context.targets))
        
        for target in context.targets:
            if str(target) not in ('TIMESTAMP', 'TARGETS', 'MULTIPLE'):
                widget.drag_get_data(context, target, time)

        cb_service.set_object_percent(object_id, percent=100)
        
        return True

    def drag_data_received_cb(self, widget, context, x, y, selection, targetType, time):
        logging.debug('ClipboardBox: got data for target %r' % selection.target)
        try:
            if selection:
                object_id = self._context_map.get_object_id(context)
                self._add_selection(object_id, selection)
            else:
                logging.warn('ClipboardBox: empty selection for target ' + selection.target)
        finally:
            # If it's the last target to be processed, finish the dnd transaction
            if not self._context_map.has_context(context):
                context.drop_finish(True, gtk.get_current_event_time())

    def drag_data_get_cb(self, widget, context, selection, targetType, eventTime):
        logging.debug("drag_data_get_cb: requested target " + selection.target)
        
        object_id = self._last_clicked_icon.get_object_id()
        cb_service = clipboardservice.get_instance()
        data = cb_service.get_object_data(object_id, selection.target)['DATA']
        
        selection.set(selection.target, 8, data)

    def button_press_event_cb(self, widget, event):
        logging.debug("button_press_event_cb")

        if event.button == 1 and event.type == gtk.gdk.BUTTON_PRESS:
            self._last_clicked_icon = self._get_icon_at_coords(event.x, event.y)
            if self._last_clicked_icon:
                self._pressed_button = event.button
                self._press_start_x = event.x
                self._press_start_y = event.y

        return False

    def motion_notify_event_cb(self, widget, event):
       
        if not self._pressed_button:
            return True
        
        # if the mouse button is not pressed, no drag should occurr
        if not event.state & gtk.gdk.BUTTON1_MASK:
            self._pressed_button = None
            return True

        logging.debug("motion_notify_event_cb")
                        
        if event.is_hint:
            x, y, state = event.window.get_pointer()
        else:
            x = event.x
            y = event.y
            state = event.state

        if widget.drag_check_threshold(int(self._press_start_x),
                                       int(self._press_start_y),
                                       int(x),
                                       int(y)):
            targets = self._get_object_targets(
                self._last_clicked_icon.get_object_id())

            context = widget.drag_begin(targets,
                                        gtk.gdk.ACTION_COPY,
                                        1,
                                        event);

        return True

    def drag_end_cb(self, widget, drag_context):
        logging.debug("drag_end_cb")
        self._pressed_button = None

    def _get_object_targets(self, object_id):
        cb_service = clipboardservice.get_instance()

        attrs = cb_service.get_object(object_id)
        format_types = attrs[clipboardservice.FORMATS_KEY]
        
        targets = []        
        for format_type in format_types:
            targets.append((format_type, 0, 0))
        
        return targets