1 #define __SP_DOCUMENT_UNDO_C__
3 /** \file
4 * Undo/Redo stack implementation
5 *
6 * Authors:
7 * Lauris Kaplinski <lauris@kaplinski.com>
8 * MenTaLguY <mental@rydia.net>
9 *
10 * Copyright (C) 2007 MenTaLguY <mental@rydia.net>
11 * Copyright (C) 1999-2003 authors
12 * Copyright (C) 2001-2002 Ximian, Inc.
13 *
14 * Released under GNU GPL, read the file 'COPYING' for more information
15 *
16 * Using the split document model gives sodipodi a very simple and clean
17 * undo implementation. Whenever mutation occurs in the XML tree,
18 * SPObject invokes one of the five corresponding handlers of its
19 * container document. This writes down a generic description of the
20 * given action, and appends it to the recent action list, kept by the
21 * document. There will be as many action records as there are mutation
22 * events, which are all kept and processed together in the undo
23 * stack. Two methods exist to indicate that the given action is completed:
24 *
25 * \verbatim
26 void sp_document_done (SPDocument *document);
27 void sp_document_maybe_done (SPDocument *document, const unsigned char *key) \endverbatim
28 *
29 * Both move the recent action list into the undo stack and clear the
30 * list afterwards. While the first method does an unconditional push,
31 * the second one first checks the key of the most recent stack entry. If
32 * the keys are identical, the current action list is appended to the
33 * existing stack entry, instead of pushing it onto its own. This
34 * behaviour can be used to collect multi-step actions (like winding the
35 * Gtk spinbutton) from the UI into a single undoable step.
36 *
37 * For controls implemented by Sodipodi itself, implementing undo as a
38 * single step is usually done in a more efficent way. Most controls have
39 * the abstract model of grab, drag, release, and change user
40 * action. During the grab phase, all modifications are done to the
41 * SPObject directly - i.e. they do not change XML tree, and thus do not
42 * generate undo actions either. Only at the release phase (normally
43 * associated with releasing the mousebutton), changes are written back
44 * to the XML tree, thus generating only a single set of undo actions.
45 * (Lauris Kaplinski)
46 */
48 #ifdef HAVE_CONFIG_H
49 # include "config.h"
50 #endif
54 #if HAVE_STRING_H
55 #endif
58 #if HAVE_STDLIB_H
59 #endif
61 #include "xml/repr.h"
62 #include "document-private.h"
63 #include "inkscape.h"
64 #include "debug/event-tracker.h"
65 #include "debug/simple-event.h"
66 #include "debug/timestamp.h"
67 #include "event.h"
70 /*
71 * Undo & redo
72 */
73 /**
74 * Set undo sensitivity.
75 *
76 * \note
77 * Since undo sensitivity needs to be nested, setting undo sensitivity
78 * should be done like this:
79 *\verbatim
80 bool saved = sp_document_get_undo_sensitive(document);
81 sp_document_set_undo_sensitive(document, false);
82 ... do stuff ...
83 sp_document_set_undo_sensitive(document, saved); \endverbatim
84 */
85 void
86 sp_document_set_undo_sensitive (SPDocument *doc, bool sensitive)
87 {
88 g_assert (doc != NULL);
89 g_assert (doc->priv != NULL);
91 if ( sensitive == doc->priv->sensitive )
92 return;
94 if (sensitive) {
95 sp_repr_begin_transaction (doc->rdoc);
96 } else {
97 doc->priv->partial = sp_repr_coalesce_log (
98 doc->priv->partial,
99 sp_repr_commit_undoable (doc->rdoc)
100 );
101 }
103 doc->priv->sensitive = sensitive;
104 }
106 /*TODO: Throughout the inkscape code tree set/get_undo_sensitive are used for
107 * as is shown above. Perhaps it makes sense to create new functions,
108 * undo_ignore, and undo_recall to replace the start and end parts of the above.
109 * The main complexity with this is that they have to nest, so you have to store
110 * the saved bools in a stack. Perhaps this is why the above solution is better.
111 */
113 bool sp_document_get_undo_sensitive(SPDocument const *document) {
114 g_assert(document != NULL);
115 g_assert(document->priv != NULL);
117 return document->priv->sensitive;
118 }
120 void
121 sp_document_done (SPDocument *doc, const unsigned int event_type, Glib::ustring event_description)
122 {
123 sp_document_maybe_done (doc, NULL, event_type, event_description);
124 }
126 void
127 sp_document_reset_key (Inkscape::Application *inkscape, SPDesktop *desktop, GtkObject *base)
128 {
129 SPDocument *doc = (SPDocument *) base;
130 doc->actionkey = NULL;
131 }
133 namespace {
135 using Inkscape::Debug::Event;
136 using Inkscape::Debug::SimpleEvent;
137 using Inkscape::Util::share_static_string;
138 using Inkscape::Debug::timestamp;
139 using Inkscape::Verb;
141 typedef SimpleEvent<Event::INTERACTION> InteractionEvent;
143 class CommitEvent : public InteractionEvent {
144 public:
146 CommitEvent(SPDocument *doc, const gchar *key, const unsigned int type)
147 : InteractionEvent(share_static_string("commit"))
148 {
149 _addProperty(share_static_string("timestamp"), timestamp());
150 gchar *serial = g_strdup_printf("%lu", doc->serial());
151 _addProperty(share_static_string("document"), serial);
152 g_free(serial);
153 Verb *verb = Verb::get(type);
154 if (verb) {
155 _addProperty(share_static_string("context"), verb->get_id());
156 }
157 if (key) {
158 _addProperty(share_static_string("merge-key"), key);
159 }
160 }
161 };
163 }
165 void
166 sp_document_maybe_done (SPDocument *doc, const gchar *key, const unsigned int event_type,
167 Glib::ustring event_description)
168 {
169 g_assert (doc != NULL);
170 g_assert (doc->priv != NULL);
171 g_assert (doc->priv->sensitive);
173 Inkscape::Debug::EventTracker<CommitEvent> tracker(doc, key, event_type);
175 doc->collectOrphans();
177 sp_document_ensure_up_to_date (doc);
179 sp_document_clear_redo (doc);
181 Inkscape::XML::Event *log = sp_repr_coalesce_log (doc->priv->partial, sp_repr_commit_undoable (doc->rdoc));
182 doc->priv->partial = NULL;
184 if (!log) {
185 sp_repr_begin_transaction (doc->rdoc);
186 return;
187 }
189 if (key && doc->actionkey && !strcmp (key, doc->actionkey) && doc->priv->undo) {
190 ((Inkscape::Event *)doc->priv->undo->data)->event =
191 sp_repr_coalesce_log (((Inkscape::Event *)doc->priv->undo->data)->event, log);
192 } else {
193 Inkscape::Event *event = new Inkscape::Event(log, event_type, event_description);
194 doc->priv->undo = g_slist_prepend (doc->priv->undo, event);
195 doc->priv->history_size++;
196 doc->priv->undoStackObservers.notifyUndoCommitEvent(event);
197 }
199 doc->actionkey = key;
201 doc->virgin = FALSE;
202 if (!doc->rroot->attribute("sodipodi:modified")) {
203 doc->rroot->setAttribute("sodipodi:modified", "true");
204 }
206 sp_repr_begin_transaction (doc->rdoc);
208 doc->priv->commit_signal.emit();
209 }
211 void
212 sp_document_cancel (SPDocument *doc)
213 {
214 g_assert (doc != NULL);
215 g_assert (doc->priv != NULL);
216 g_assert (doc->priv->sensitive);
218 sp_repr_rollback (doc->rdoc);
220 if (doc->priv->partial) {
221 sp_repr_undo_log (doc->priv->partial);
222 sp_repr_free_log (doc->priv->partial);
223 doc->priv->partial = NULL;
224 }
226 sp_repr_begin_transaction (doc->rdoc);
227 }
229 static void finish_incomplete_transaction(SPDocument &doc) {
230 SPDocumentPrivate &priv=*doc.priv;
231 Inkscape::XML::Event *log=sp_repr_commit_undoable(doc.rdoc);
232 if (log || priv.partial) {
233 g_warning ("Incomplete undo transaction:");
234 priv.partial = sp_repr_coalesce_log(priv.partial, log);
235 sp_repr_debug_print_log(priv.partial);
236 Inkscape::Event *event = new Inkscape::Event(priv.partial);
237 priv.undo = g_slist_prepend(priv.undo, event);
238 priv.undoStackObservers.notifyUndoCommitEvent(event);
239 priv.partial = NULL;
240 }
241 }
243 gboolean
244 sp_document_undo (SPDocument *doc)
245 {
246 using Inkscape::Debug::EventTracker;
247 using Inkscape::Debug::SimpleEvent;
249 gboolean ret;
251 EventTracker<SimpleEvent<Inkscape::Debug::Event::DOCUMENT> > tracker("undo");
253 g_assert (doc != NULL);
254 g_assert (doc->priv != NULL);
255 g_assert (doc->priv->sensitive);
257 doc->priv->sensitive = FALSE;
258 doc->priv->seeking = true;
260 doc->actionkey = NULL;
262 finish_incomplete_transaction(*doc);
264 if (doc->priv->undo) {
265 Inkscape::Event *log=(Inkscape::Event *)doc->priv->undo->data;
266 doc->priv->undo = g_slist_remove (doc->priv->undo, log);
267 sp_repr_undo_log (log->event);
268 doc->priv->redo = g_slist_prepend (doc->priv->redo, log);
270 doc->rroot->setAttribute("sodipodi:modified", "true");
271 doc->priv->undoStackObservers.notifyUndoEvent(log);
273 ret = TRUE;
274 } else {
275 ret = FALSE;
276 }
278 sp_repr_begin_transaction (doc->rdoc);
280 doc->priv->sensitive = TRUE;
281 doc->priv->seeking = false;
283 if (ret)
284 inkscape_external_change();
286 return ret;
287 }
289 gboolean
290 sp_document_redo (SPDocument *doc)
291 {
292 using Inkscape::Debug::EventTracker;
293 using Inkscape::Debug::SimpleEvent;
295 gboolean ret;
297 EventTracker<SimpleEvent<Inkscape::Debug::Event::DOCUMENT> > tracker("redo");
299 g_assert (doc != NULL);
300 g_assert (doc->priv != NULL);
301 g_assert (doc->priv->sensitive);
303 doc->priv->sensitive = FALSE;
304 doc->priv->seeking = true;
306 doc->actionkey = NULL;
308 finish_incomplete_transaction(*doc);
310 if (doc->priv->redo) {
311 Inkscape::Event *log=(Inkscape::Event *)doc->priv->redo->data;
312 doc->priv->redo = g_slist_remove (doc->priv->redo, log);
313 sp_repr_replay_log (log->event);
314 doc->priv->undo = g_slist_prepend (doc->priv->undo, log);
316 doc->rroot->setAttribute("sodipodi:modified", "true");
317 doc->priv->undoStackObservers.notifyRedoEvent(log);
319 ret = TRUE;
320 } else {
321 ret = FALSE;
322 }
324 sp_repr_begin_transaction (doc->rdoc);
326 doc->priv->sensitive = TRUE;
327 doc->priv->seeking = false;
329 if (ret)
330 inkscape_external_change();
332 return ret;
333 }
335 void
336 sp_document_clear_undo (SPDocument *doc)
337 {
338 if (doc->priv->undo)
339 doc->priv->undoStackObservers.notifyClearUndoEvent();
341 while (doc->priv->undo) {
342 GSList *current;
344 current = doc->priv->undo;
345 doc->priv->undo = current->next;
346 doc->priv->history_size--;
348 delete ((Inkscape::Event *) current->data);
349 g_slist_free_1 (current);
350 }
351 }
353 void
354 sp_document_clear_redo (SPDocument *doc)
355 {
356 if (doc->priv->redo)
357 doc->priv->undoStackObservers.notifyClearRedoEvent();
359 while (doc->priv->redo) {
360 GSList *current;
362 current = doc->priv->redo;
363 doc->priv->redo = current->next;
364 doc->priv->history_size--;
366 delete ((Inkscape::Event *) current->data);
367 g_slist_free_1 (current);
368 }
369 }
370 /*
371 Local Variables:
372 mode:c++
373 c-file-style:"stroustrup"
374 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
375 indent-tabs-mode:nil
376 fill-column:99
377 End:
378 */
379 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :