1 /**
2 * This file Copyright (c) 2013-2018 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.ui.mediaeditor.data;
35
36 import info.magnolia.ui.api.action.ActionExecutionException;
37
38 /**
39 * Interface that maintains the state of media currently open in media editor.
40 * Additionally, the state of undoLastState and redoLastState operations performed to undoLastState/redoLastState
41 * previous state modification is maintained.
42 *
43 * The original value is buffered and the state can always be rolled back to it.
44 */
45 public interface MediaState {
46
47 /**
48 * Listener interface that receives important information
49 * about the media state workflow.
50 */
51 interface Listener {
52
53 void errorOccurred(String message, Throwable e);
54 }
55
56 void setListener(Listener listener);
57
58 /**
59 * Clears modification history which erases all the tracked steps.
60 * After this method call it will be impossible to undoLastState/redoLastState operations.
61 */
62 void clearState();
63
64 /**
65 * Starts an action which will create a new state of the media opened in the media editor.
66 *
67 * @param actionName the name of an action that performs the modification.
68 */
69 void performMediaModification(String actionName);
70
71 /**
72 * Undo last media state modification.
73 */
74 void undoLastState() throws ActionExecutionException;
75
76 /**
77 * @return true, if any state modifications of media open in media editor exist
78 */
79 boolean canUndoLastState();
80
81 /**
82 * @return true, if any undone action history exists
83 */
84 boolean canRedoLastState();
85
86 /**
87 * Redo last media state modification.
88 */
89 void redoLastState() throws ActionExecutionException;
90
91 /**
92 * Propagate changes to the original media state.
93 */
94 void commitState();
95
96 /**
97 * Roll back to original media state.
98 */
99 void revertState();
100
101 /**
102 * @return the current state of media in the media editor
103 */
104 byte[] getState();
105
106 /**
107 * @param newState set the current state of the media to the newState.
108 */
109 void setState(byte[] newState);
110 }