1 /* nautilus-file-undo-manager.c - Manages the undo/redo stack
2  *
3  * Copyright (C) 2007-2011 Amos Brocco
4  * Copyright (C) 2010, 2012 Red Hat, Inc.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  *
19  * Authors: Amos Brocco <amos.brocco@gmail.com>
20  *          Cosimo Cecchi <cosimoc@redhat.com>
21  *
22  */
23 
24 #include <config.h>
25 
26 #include "nautilus-file-undo-manager.h"
27 
28 #include "nautilus-file-operations.h"
29 #include "nautilus-file.h"
30 #include "nautilus-trash-monitor.h"
31 
32 #include <glib/gi18n.h>
33 
34 #define DEBUG_FLAG NAUTILUS_DEBUG_UNDO
35 #include "nautilus-debug.h"
36 
37 enum
38 {
39     SIGNAL_UNDO_CHANGED,
40     NUM_SIGNALS,
41 };
42 
43 static guint signals[NUM_SIGNALS] = { 0, };
44 
45 struct _NautilusFileUndoManager
46 {
47     GObject parent_instance;
48     NautilusFileUndoInfo *info;
49     NautilusFileUndoManagerState state;
50     NautilusFileUndoManagerState last_state;
51 
52     guint is_operating : 1;
53 
54     gulong trash_signal_id;
55 };
56 
57 G_DEFINE_TYPE (NautilusFileUndoManager, nautilus_file_undo_manager, G_TYPE_OBJECT)
58 
59 static NautilusFileUndoManager *undo_singleton = NULL;
60 
61 NautilusFileUndoManager *
nautilus_file_undo_manager_new(void)62 nautilus_file_undo_manager_new (void)
63 {
64     if (undo_singleton != NULL)
65     {
66         return g_object_ref (undo_singleton);
67     }
68 
69     undo_singleton = g_object_new (NAUTILUS_TYPE_FILE_UNDO_MANAGER, NULL);
70     g_object_add_weak_pointer (G_OBJECT (undo_singleton), (gpointer) & undo_singleton);
71 
72     return undo_singleton;
73 }
74 
75 static void
file_undo_manager_clear(NautilusFileUndoManager * self)76 file_undo_manager_clear (NautilusFileUndoManager *self)
77 {
78     g_clear_object (&self->info);
79     self->state = NAUTILUS_FILE_UNDO_MANAGER_STATE_NONE;
80 }
81 
82 static void
trash_state_changed_cb(NautilusTrashMonitor * monitor,gboolean is_empty,gpointer user_data)83 trash_state_changed_cb (NautilusTrashMonitor *monitor,
84                         gboolean              is_empty,
85                         gpointer              user_data)
86 {
87     NautilusFileUndoManager *self = user_data;
88 
89     /* A trash operation cannot be undone if the trash is empty */
90     if (is_empty &&
91         self->state == NAUTILUS_FILE_UNDO_MANAGER_STATE_UNDO &&
92         NAUTILUS_IS_FILE_UNDO_INFO_TRASH (self->info))
93     {
94         file_undo_manager_clear (self);
95         g_signal_emit (self, signals[SIGNAL_UNDO_CHANGED], 0);
96     }
97 }
98 
99 static void
nautilus_file_undo_manager_init(NautilusFileUndoManager * self)100 nautilus_file_undo_manager_init (NautilusFileUndoManager *self)
101 {
102     self->trash_signal_id = g_signal_connect (nautilus_trash_monitor_get (),
103                                               "trash-state-changed",
104                                               G_CALLBACK (trash_state_changed_cb), self);
105 }
106 
107 static void
nautilus_file_undo_manager_finalize(GObject * object)108 nautilus_file_undo_manager_finalize (GObject *object)
109 {
110     NautilusFileUndoManager *self = NAUTILUS_FILE_UNDO_MANAGER (object);
111 
112     g_clear_signal_handler (&self->trash_signal_id, nautilus_trash_monitor_get ());
113 
114     file_undo_manager_clear (self);
115 
116     G_OBJECT_CLASS (nautilus_file_undo_manager_parent_class)->finalize (object);
117 }
118 
119 static void
nautilus_file_undo_manager_class_init(NautilusFileUndoManagerClass * klass)120 nautilus_file_undo_manager_class_init (NautilusFileUndoManagerClass *klass)
121 {
122     GObjectClass *oclass;
123 
124     oclass = G_OBJECT_CLASS (klass);
125 
126     oclass->finalize = nautilus_file_undo_manager_finalize;
127 
128     signals[SIGNAL_UNDO_CHANGED] =
129         g_signal_new ("undo-changed",
130                       G_TYPE_FROM_CLASS (klass),
131                       G_SIGNAL_RUN_LAST,
132                       0, NULL, NULL,
133                       g_cclosure_marshal_VOID__VOID,
134                       G_TYPE_NONE, 0);
135 }
136 
137 static void
undo_info_apply_ready(GObject * source,GAsyncResult * res,gpointer user_data)138 undo_info_apply_ready (GObject      *source,
139                        GAsyncResult *res,
140                        gpointer      user_data)
141 {
142     NautilusFileUndoManager *self = user_data;
143     NautilusFileUndoInfo *info = NAUTILUS_FILE_UNDO_INFO (source);
144     gboolean success, user_cancel;
145 
146     success = nautilus_file_undo_info_apply_finish (info, res, &user_cancel, NULL);
147 
148     self->is_operating = FALSE;
149 
150     /* just return in case we got another another operation set */
151     if ((self->info != NULL) &&
152         (self->info != info))
153     {
154         return;
155     }
156 
157     if (success)
158     {
159         if (self->last_state == NAUTILUS_FILE_UNDO_MANAGER_STATE_UNDO)
160         {
161             self->state = NAUTILUS_FILE_UNDO_MANAGER_STATE_REDO;
162         }
163         else if (self->last_state == NAUTILUS_FILE_UNDO_MANAGER_STATE_REDO)
164         {
165             self->state = NAUTILUS_FILE_UNDO_MANAGER_STATE_UNDO;
166         }
167 
168         self->info = g_object_ref (info);
169     }
170     else if (user_cancel)
171     {
172         self->state = self->last_state;
173         self->info = g_object_ref (info);
174     }
175     else
176     {
177         file_undo_manager_clear (self);
178     }
179 
180     g_signal_emit (self, signals[SIGNAL_UNDO_CHANGED], 0);
181 }
182 
183 static void
do_undo_redo(NautilusFileUndoManager * self,GtkWindow * parent_window,NautilusFileOperationsDBusData * dbus_data)184 do_undo_redo (NautilusFileUndoManager        *self,
185               GtkWindow                      *parent_window,
186               NautilusFileOperationsDBusData *dbus_data)
187 {
188     gboolean undo = self->state == NAUTILUS_FILE_UNDO_MANAGER_STATE_UNDO;
189 
190     self->last_state = self->state;
191 
192     self->is_operating = TRUE;
193     nautilus_file_undo_info_apply_async (self->info, undo, parent_window,
194                                          dbus_data,
195                                          undo_info_apply_ready, self);
196 
197     /* clear actions while undoing */
198     file_undo_manager_clear (self);
199     g_signal_emit (self, signals[SIGNAL_UNDO_CHANGED], 0);
200 }
201 
202 void
nautilus_file_undo_manager_redo(GtkWindow * parent_window,NautilusFileOperationsDBusData * dbus_data)203 nautilus_file_undo_manager_redo (GtkWindow                      *parent_window,
204                                  NautilusFileOperationsDBusData *dbus_data)
205 {
206     if (undo_singleton->state != NAUTILUS_FILE_UNDO_MANAGER_STATE_REDO)
207     {
208         g_warning ("Called redo, but state is %s!", undo_singleton->state == 0 ?
209                    "none" : "undo");
210         return;
211     }
212 
213     do_undo_redo (undo_singleton, parent_window, dbus_data);
214 }
215 
216 void
nautilus_file_undo_manager_undo(GtkWindow * parent_window,NautilusFileOperationsDBusData * dbus_data)217 nautilus_file_undo_manager_undo (GtkWindow                      *parent_window,
218                                  NautilusFileOperationsDBusData *dbus_data)
219 {
220     if (undo_singleton->state != NAUTILUS_FILE_UNDO_MANAGER_STATE_UNDO)
221     {
222         g_warning ("Called undo, but state is %s!", undo_singleton->state == 0 ?
223                    "none" : "redo");
224         return;
225     }
226 
227     do_undo_redo (undo_singleton, parent_window, dbus_data);
228 }
229 
230 void
nautilus_file_undo_manager_set_action(NautilusFileUndoInfo * info)231 nautilus_file_undo_manager_set_action (NautilusFileUndoInfo *info)
232 {
233     DEBUG ("Setting undo information %p", info);
234 
235     file_undo_manager_clear (undo_singleton);
236 
237     if (info != NULL)
238     {
239         undo_singleton->info = g_object_ref (info);
240         undo_singleton->state = NAUTILUS_FILE_UNDO_MANAGER_STATE_UNDO;
241         undo_singleton->last_state = NAUTILUS_FILE_UNDO_MANAGER_STATE_NONE;
242     }
243 
244     g_signal_emit (undo_singleton, signals[SIGNAL_UNDO_CHANGED], 0);
245 }
246 
247 NautilusFileUndoInfo *
nautilus_file_undo_manager_get_action(void)248 nautilus_file_undo_manager_get_action (void)
249 {
250     return undo_singleton->info;
251 }
252 
253 NautilusFileUndoManagerState
nautilus_file_undo_manager_get_state(void)254 nautilus_file_undo_manager_get_state (void)
255 {
256     return undo_singleton->state;
257 }
258 
259 
260 gboolean
nautilus_file_undo_manager_is_operating()261 nautilus_file_undo_manager_is_operating ()
262 {
263     return undo_singleton->is_operating;
264 }
265 
266 NautilusFileUndoManager *
nautilus_file_undo_manager_get()267 nautilus_file_undo_manager_get ()
268 {
269     return undo_singleton;
270 }
271