1/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2/* ***** BEGIN LICENSE BLOCK *****
3 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4 *
5 * The contents of this file are subject to the Mozilla Public License Version
6 * 1.1 (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 * http://www.mozilla.org/MPL/
9 *
10 * Software distributed under the License is distributed on an "AS IS" basis,
11 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12 * for the specific language governing rights and limitations under the
13 * License.
14 *
15 * The Original Code is mozilla.org code.
16 *
17 * The Initial Developer of the Original Code is
18 * Netscape Communications Corporation.
19 * Portions created by the Initial Developer are Copyright (C) 1998
20 * the Initial Developer. All Rights Reserved.
21 *
22 * Contributor(s):
23 *   Author: Aaron Leventhal (aaronl@netscape.com)
24 *
25 * Alternatively, the contents of this file may be used under the terms of
26 * either of the GNU General Public License Version 2 or later (the "GPL"),
27 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
28 * in which case the provisions of the GPL or the LGPL are applicable instead
29 * of those above. If you wish to allow use of your version of this file only
30 * under the terms of either the GPL or the LGPL, and not to allow others to
31 * use your version of this file under the terms of the MPL, indicate your
32 * decision by deleting the provisions above and replace them with the notice
33 * and other provisions required by the GPL or the LGPL. If you do not delete
34 * the provisions above, a recipient may use your version of this file under
35 * the terms of any one of the MPL, the GPL or the LGPL.
36 *
37 * ***** END LICENSE BLOCK ***** */
38
39#include "imgIContainer.h"
40#include "imgIRequest.h"
41
42#include "nsHTMLImageAccessible.h"
43#include "nsAccessibilityAtoms.h"
44#include "nsHTMLAreaAccessible.h"
45
46#include "nsIDOMHTMLCollection.h"
47#include "nsIDocument.h"
48#include "nsIHTMLDocument.h"
49#include "nsIImageLoadingContent.h"
50#include "nsILink.h"
51#include "nsIPresShell.h"
52#include "nsIServiceManager.h"
53#include "nsIDOMHTMLImageElement.h"
54#include "nsIDOMDocument.h"
55#include "nsPIDOMWindow.h"
56
57// --- image -----
58
59const PRUint32 kDefaultImageCacheSize = 256;
60
61////////////////////////////////////////////////////////////////////////////////
62// nsHTMLImageAccessible
63
64nsHTMLImageAccessible::nsHTMLImageAccessible(nsIDOMNode* aDOMNode, nsIWeakReference* aShell):
65nsLinkableAccessible(aDOMNode, aShell), mAccessNodeCache(nsnull)
66{ 
67  nsCOMPtr<nsIDOMElement> element(do_QueryInterface(aDOMNode));
68  nsCOMPtr<nsIPresShell> shell(do_QueryReferent(mWeakShell));
69  if (!shell)
70    return;
71
72  nsIDocument *doc = shell->GetDocument();
73  nsAutoString mapElementName;
74
75  if (doc && element) {
76    nsCOMPtr<nsIHTMLDocument> htmlDoc(do_QueryInterface(doc));
77    element->GetAttribute(NS_LITERAL_STRING("usemap"),mapElementName);
78    if (htmlDoc && !mapElementName.IsEmpty()) {
79      if (mapElementName.CharAt(0) == '#')
80        mapElementName.Cut(0,1);
81      mMapElement = htmlDoc->GetImageMap(mapElementName);
82    }
83  }
84
85  if (mMapElement) {
86    mAccessNodeCache = new nsAccessNodeHashtable();
87    mAccessNodeCache->Init(kDefaultImageCacheSize);
88  }
89}
90
91NS_IMPL_ISUPPORTS_INHERITED1(nsHTMLImageAccessible, nsAccessible,
92                             nsIAccessibleImage)
93
94////////////////////////////////////////////////////////////////////////////////
95// nsIAccessible
96
97nsresult
98nsHTMLImageAccessible::GetStateInternal(PRUint32 *aState, PRUint32 *aExtraState)
99{
100  // The state is a bitfield, get our inherited state, then logically OR it with
101  // STATE_ANIMATED if this is an animated image.
102
103  nsresult rv = nsLinkableAccessible::GetStateInternal(aState, aExtraState);
104  NS_ENSURE_A11Y_SUCCESS(rv, rv);
105
106  nsCOMPtr<nsIImageLoadingContent> content(do_QueryInterface(mDOMNode));
107  nsCOMPtr<imgIRequest> imageRequest;
108
109  if (content)
110    content->GetRequest(nsIImageLoadingContent::CURRENT_REQUEST,
111                        getter_AddRefs(imageRequest));
112
113  nsCOMPtr<imgIContainer> imgContainer;
114  if (imageRequest)
115    imageRequest->GetImage(getter_AddRefs(imgContainer));
116
117  if (imgContainer) {
118    PRUint32 numFrames;
119    imgContainer->GetNumFrames(&numFrames);
120    if (numFrames > 1)
121      *aState |= nsIAccessibleStates::STATE_ANIMATED;
122  }
123
124  return NS_OK;
125}
126
127nsresult
128nsHTMLImageAccessible::GetNameInternal(nsAString& aName)
129{
130  nsCOMPtr<nsIContent> content(do_QueryInterface(mDOMNode));
131  PRBool hasAltAttrib =
132    content->GetAttr(kNameSpaceID_None, nsAccessibilityAtoms::alt, aName);
133  if (!aName.IsEmpty())
134    return NS_OK;
135
136  nsresult rv = nsAccessible::GetNameInternal(aName);
137  NS_ENSURE_SUCCESS(rv, rv);
138
139  if (aName.IsEmpty() && hasAltAttrib) {
140    // No accessible name but empty 'alt' attribute is present. If further name
141    // computation algorithm doesn't provide non empty name then it means
142    // an empty 'alt' attribute was used to indicate a decorative image (see
143    // nsIAccessible::name attribute for details).
144    return NS_OK_EMPTY_NAME;
145  }
146
147  return NS_OK;
148}
149
150nsresult
151nsHTMLImageAccessible::GetRoleInternal(PRUint32 *aRole)
152{
153  *aRole = mMapElement ? nsIAccessibleRole::ROLE_IMAGE_MAP :
154                         nsIAccessibleRole::ROLE_GRAPHIC;
155  return NS_OK;
156}
157
158void nsHTMLImageAccessible::CacheChildren()
159{
160  if (!mWeakShell) {
161    // This node has been shut down
162    mAccChildCount = eChildCountUninitialized;
163    return;
164  }
165
166  if (mAccChildCount != eChildCountUninitialized) {
167    return;
168  }
169
170  mAccChildCount = 0;
171  nsCOMPtr<nsIDOMHTMLCollection> mapAreas = GetAreaCollection();
172  if (!mapAreas)
173    return;
174
175  PRUint32 numMapAreas;
176  mapAreas->GetLength(&numMapAreas);
177  PRInt32 childCount = 0;
178  
179  nsCOMPtr<nsIAccessible> areaAccessible;
180  nsRefPtr<nsAccessible> prevAcc;
181  while (childCount < (PRInt32)numMapAreas && 
182         (areaAccessible = GetAreaAccessible(mapAreas, childCount)) != nsnull) {
183    if (prevAcc)
184      prevAcc->SetNextSibling(areaAccessible);
185    else
186      SetFirstChild(areaAccessible);
187
188    ++ childCount;
189
190    prevAcc = nsAccUtils::QueryAccessible(areaAccessible);
191    prevAcc->SetParent(this);
192  }
193  mAccChildCount = childCount;
194}
195
196NS_IMETHODIMP
197nsHTMLImageAccessible::GetNumActions(PRUint8 *aNumActions)
198{
199  NS_ENSURE_ARG_POINTER(aNumActions);
200  *aNumActions = 0;
201
202  if (IsDefunct())
203    return NS_ERROR_FAILURE;
204
205  nsresult rv= nsLinkableAccessible::GetNumActions(aNumActions);
206  NS_ENSURE_SUCCESS(rv, rv);
207
208  if (HasLongDesc())
209    (*aNumActions)++;
210
211  return NS_OK;
212}
213
214NS_IMETHODIMP
215nsHTMLImageAccessible::GetActionName(PRUint8 aIndex, nsAString& aName)
216{
217  aName.Truncate();
218
219  if (IsDefunct())
220    return NS_ERROR_FAILURE;
221
222  if (IsValidLongDescIndex(aIndex)) {
223    aName.AssignLiteral("showlongdesc"); 
224    return NS_OK;
225  }
226  return nsLinkableAccessible::GetActionName(aIndex, aName);
227}
228
229NS_IMETHODIMP
230nsHTMLImageAccessible::DoAction(PRUint8 aIndex)
231{
232  if (IsDefunct())
233    return NS_ERROR_FAILURE;
234
235  if (IsValidLongDescIndex(aIndex)) {
236    //get the long description uri and open in a new window
237    nsCOMPtr<nsIDOMHTMLImageElement> element(do_QueryInterface(mDOMNode));
238    NS_ENSURE_TRUE(element, NS_ERROR_FAILURE);
239    nsAutoString longDesc;
240    nsresult rv = element->GetLongDesc(longDesc);
241    NS_ENSURE_SUCCESS(rv, rv);
242    nsCOMPtr<nsIDOMDocument> domDocument;
243    rv = mDOMNode->GetOwnerDocument(getter_AddRefs(domDocument));
244    NS_ENSURE_SUCCESS(rv, rv);
245    nsCOMPtr<nsIDocument> document(do_QueryInterface(domDocument));
246    nsCOMPtr<nsPIDOMWindow> piWindow = document->GetWindow();
247    nsCOMPtr<nsIDOMWindowInternal> win(do_QueryInterface(piWindow));
248    NS_ENSURE_TRUE(win, NS_ERROR_FAILURE);
249    nsCOMPtr<nsIDOMWindow> tmp;
250    return win->Open(longDesc, NS_LITERAL_STRING(""), NS_LITERAL_STRING(""),
251                     getter_AddRefs(tmp));
252  }
253  return nsLinkableAccessible::DoAction(aIndex);
254}
255
256////////////////////////////////////////////////////////////////////////////////
257// nsIAccessibleHyperLink
258NS_IMETHODIMP
259nsHTMLImageAccessible::GetAnchorCount(PRInt32 *aAnchorCount)
260{
261  NS_ENSURE_ARG_POINTER(aAnchorCount);
262
263  if (!mMapElement)
264    return nsLinkableAccessible::GetAnchorCount(aAnchorCount);
265
266  return GetChildCount(aAnchorCount);
267}
268
269NS_IMETHODIMP
270nsHTMLImageAccessible::GetURI(PRInt32 aIndex, nsIURI **aURI)
271{
272  NS_ENSURE_ARG_POINTER(aURI);
273  *aURI = nsnull;
274
275  if (!mMapElement)
276    return nsLinkableAccessible::GetURI(aIndex, aURI);
277
278  nsCOMPtr<nsIDOMHTMLCollection> mapAreas = GetAreaCollection();
279  if (!mapAreas)
280    return NS_OK;
281  
282  nsCOMPtr<nsIDOMNode> domNode;
283  mapAreas->Item(aIndex, getter_AddRefs(domNode));
284  if (!domNode)
285    return NS_ERROR_INVALID_ARG;
286
287  nsCOMPtr<nsILink> link(do_QueryInterface(domNode));
288  if (link)
289    link->GetHrefURI(aURI);
290
291  return NS_OK;
292}
293
294NS_IMETHODIMP
295nsHTMLImageAccessible::GetAnchor(PRInt32 aIndex, nsIAccessible **aAccessible)
296{
297  NS_ENSURE_ARG_POINTER(aAccessible);
298  *aAccessible = nsnull;
299
300  if (!mMapElement)
301    return nsLinkableAccessible::GetAnchor(aIndex, aAccessible);
302
303  nsCOMPtr<nsIDOMHTMLCollection> mapAreas = GetAreaCollection();
304  if (mapAreas) {
305    nsCOMPtr<nsIAccessible> accessible;
306    accessible = GetAreaAccessible(mapAreas, aIndex);
307    if (!accessible)
308      return NS_ERROR_INVALID_ARG;
309
310    NS_ADDREF(*aAccessible = accessible);
311  }
312
313  return NS_OK;
314}
315
316////////////////////////////////////////////////////////////////////////////////
317// nsIAccessibleImage
318
319NS_IMETHODIMP
320nsHTMLImageAccessible::GetImagePosition(PRUint32 aCoordType,
321                                        PRInt32 *aX, PRInt32 *aY)
322{
323  PRInt32 width, height;
324  nsresult rv = GetBounds(aX, aY, &width, &height);
325  if (NS_FAILED(rv))
326    return rv;
327
328  return nsAccUtils::ConvertScreenCoordsTo(aX, aY, aCoordType, this);
329}
330
331NS_IMETHODIMP
332nsHTMLImageAccessible::GetImageSize(PRInt32 *aWidth, PRInt32 *aHeight)
333{
334  PRInt32 x, y;
335  return GetBounds(&x, &y, aWidth, aHeight);
336}
337
338////////////////////////////////////////////////////////////////////////////////
339// nsHTMLImageAccessible. nsAccessNode
340
341nsresult
342nsHTMLImageAccessible::Shutdown()
343{
344  nsLinkableAccessible::Shutdown();
345
346  if (mAccessNodeCache) {
347    ClearCache(*mAccessNodeCache);
348    delete mAccessNodeCache;
349    mAccessNodeCache = nsnull;
350  }
351
352  return NS_OK;
353}
354
355////////////////////////////////////////////////////////////////////////////////
356// nsHTMLImageAccessible
357
358nsresult
359nsHTMLImageAccessible::GetAttributesInternal(nsIPersistentProperties *aAttributes)
360{
361  if (IsDefunct())
362    return NS_ERROR_FAILURE;
363  
364  nsresult rv = nsLinkableAccessible::GetAttributesInternal(aAttributes);
365  NS_ENSURE_SUCCESS(rv, rv);
366
367  nsCOMPtr<nsIContent> content(do_QueryInterface(mDOMNode));
368
369  nsAutoString src;
370  content->GetAttr(kNameSpaceID_None, nsAccessibilityAtoms::src, src);
371  if (!src.IsEmpty())
372    nsAccUtils::SetAccAttr(aAttributes, nsAccessibilityAtoms::src, src);
373
374  return NS_OK;
375}
376
377already_AddRefed<nsIDOMHTMLCollection>
378nsHTMLImageAccessible::GetAreaCollection()
379{
380  if (!mMapElement)
381    return nsnull;
382
383  nsIDOMHTMLCollection *mapAreas = nsnull;
384  nsresult rv = mMapElement->GetAreas(&mapAreas);
385  if (NS_FAILED(rv))
386    return nsnull;
387
388  return mapAreas;
389}
390
391already_AddRefed<nsIAccessible>
392nsHTMLImageAccessible::GetAreaAccessible(nsIDOMHTMLCollection *aAreaCollection,
393                                         PRInt32 aAreaNum)
394{
395  if (!aAreaCollection)
396    return nsnull;
397
398  nsCOMPtr<nsIDOMNode> domNode;
399  aAreaCollection->Item(aAreaNum,getter_AddRefs(domNode));
400  if (!domNode)
401    return nsnull;
402  
403  nsCOMPtr<nsIAccessNode> accessNode;
404  GetCacheEntry(*mAccessNodeCache, (void*)(aAreaNum),
405                getter_AddRefs(accessNode));
406  
407  if (!accessNode) {
408    accessNode = new nsHTMLAreaAccessible(domNode, this, mWeakShell);
409    if (!accessNode)
410      return nsnull;
411    
412    nsRefPtr<nsAccessNode> accNode = nsAccUtils::QueryAccessNode(accessNode);
413    nsresult rv = accNode->Init();
414    if (NS_FAILED(rv))
415      return nsnull;
416    
417    PutCacheEntry(*mAccessNodeCache, (void*)(aAreaNum), accessNode);
418  }
419
420  nsIAccessible *accessible = nsnull;
421  CallQueryInterface(accessNode, &accessible);
422
423  return accessible;
424}
425
426////////////////////////////////////////////////////////////////////////////////
427// Private methods
428
429PRBool
430nsHTMLImageAccessible::HasLongDesc()
431{
432  if (IsDefunct())
433    return PR_FALSE;
434
435  nsCOMPtr<nsIContent> content(do_QueryInterface(mDOMNode));
436  return (content->HasAttr(kNameSpaceID_None, nsAccessibilityAtoms::longDesc));
437}
438
439PRBool
440nsHTMLImageAccessible::IsValidLongDescIndex(PRUint8 aIndex)
441{
442  if (!HasLongDesc())
443    return PR_FALSE;
444
445  PRUint8 numActions = 0;
446  nsresult rv = nsLinkableAccessible::GetNumActions(&numActions);  
447  NS_ENSURE_SUCCESS(rv, PR_FALSE);
448
449  return (aIndex == numActions);
450}