/*

 * Copyright (C) 2009 Google Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are

 * met:

 *

 *     * Redistributions of source code must retain the above copyright

 * notice, this list of conditions and the following disclaimer.

 *     * Redistributions in binary form must reproduce the above

 * copyright notice, this list of conditions and the following disclaimer

 * in the documentation and/or other materials provided with the

 * distribution.

 *     * Neither the name of Google Inc. nor the names of its

 * contributors may be used to endorse or promote products derived from

 * this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "config.h"

#include "WebAccessibilityCacheImpl.h"

#include "AccessibilityObject.h"

#include "AXObjectCache.h"

#include "Document.h"

#include "Frame.h"

#include "WebAccessibilityObject.h"

#include "WebFrameImpl.h"

#include "WebViewImpl.h"

using namespace WebCore;

namespace WebKit {

const int invalidObjectId = -1;

const int firstObjectId = 1000;

static PassRefPtr<AccessibilityObject> toAccessibilityObject(const WebAccessibilityObject& object)

{

    return object;

}

// WebView ----------------------------------------------------------------

WebAccessibilityCache* WebAccessibilityCache::create()

{

    return new WebAccessibilityCacheImpl();

}

// WeakHandle -------------------------------------------------------------

PassRefPtr<WebAccessibilityCacheImpl::WeakHandle> WebAccessibilityCacheImpl::WeakHandle::create(AccessibilityObject* object)

{

    // FIXME: Remove resetting ref-count from AccessibilityObjectWrapper

    RefPtr<WebAccessibilityCacheImpl::WeakHandle> weakHandle = adoptRef(new WebAccessibilityCacheImpl::WeakHandle(object));

    weakHandle->m_object->setWrapper(weakHandle.get());

    return weakHandle.release();

}

WebAccessibilityCacheImpl::WeakHandle::WeakHandle(AccessibilityObject* object)

    : AccessibilityObjectWrapper(object)

{

}

// WebAccessibilityCacheImpl ----------------------------------------

void WebAccessibilityCacheImpl::WeakHandle::detach()

{

    if (m_object)

        m_object = 0;

}

WebAccessibilityCacheImpl::WebAccessibilityCacheImpl()

    : m_nextNewId(firstObjectId)

    , m_initialized(false)

{

}

WebAccessibilityCacheImpl::~WebAccessibilityCacheImpl()

{

}

void WebAccessibilityCacheImpl::initialize(WebView* view)

{

    AXObjectCache::enableAccessibility();

    WebAccessibilityObject root = view->accessibilityObject();

    if (root.isNull())

        return;

    RefPtr<AccessibilityObject> rootObject = toAccessibilityObject(root);

    // Insert root in hashmaps.

    m_objectMap.set(m_nextNewId, WeakHandle::create(rootObject.get()));

    m_idMap.set(rootObject.get(), m_nextNewId++);

    m_initialized = true;

}

WebAccessibilityObject WebAccessibilityCacheImpl::getObjectById(int id)

{

    ObjectMap::iterator it = m_objectMap.find(id);

    if (it == m_objectMap.end() || !it->second)

        return WebAccessibilityObject();

    return WebAccessibilityObject(it->second->accessibilityObject());

}

bool WebAccessibilityCacheImpl::isValidId(int id) const

{

    return id >= firstObjectId;

}

void WebAccessibilityCacheImpl::remove(int id)

{

    ObjectMap::iterator it = m_objectMap.find(id);

    if (it == m_objectMap.end())

        return;

    if (it->second) {

        // Erase element from reverse hashmap.

        IdMap::iterator it2 = m_idMap.find(it->second->accessibilityObject());

        if (it2 != m_idMap.end())

            m_idMap.remove(it2);

    }

    m_objectMap.remove(it);

}

void WebAccessibilityCacheImpl::clear()

{

    m_objectMap.clear();

    m_idMap.clear();

}

int WebAccessibilityCacheImpl::addOrGetId(const WebAccessibilityObject& object)

{

    if (object.isNull())

        return invalidObjectId;

    RefPtr<AccessibilityObject> o = toAccessibilityObject(object);

    IdMap::iterator it = m_idMap.find(o.get());

    if (it != m_idMap.end())

        return it->second;

    // Insert new accessibility object in hashmaps and return its newly

    // assigned accessibility object id.

    m_objectMap.set(m_nextNewId, WeakHandle::create(o.get()));

    m_idMap.set(o.get(), m_nextNewId);

    return m_nextNewId++;

}

}