/*

 * Copyright (C) 2006, 2007 Apple 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:

 * 1. Redistributions of source code must retain the above copyright

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

 * 2. 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.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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 "WebKitDLL.h"

#include "WebNotificationCenter.h"

#include "WebNotification.h"

#pragma warning(push, 0)

#include <WebCore/COMPtr.h>

#include <WebCore/PlatformString.h>

#include <WebCore/StringHash.h>

#include <wtf/HashMap.h>

#include <wtf/HashTraits.h>

#include <wtf/Vector.h>

#pragma warning(pop)

#include <tchar.h>

#include <utility>

using namespace WebCore;

typedef std::pair<COMPtr<IUnknown>, COMPtr<IWebNotificationObserver> > ObjectObserverPair;

typedef Vector<ObjectObserverPair> ObjectObserverList;

typedef ObjectObserverList::iterator ObserverListIterator;

typedef HashMap<String, ObjectObserverList> MappedObservers;

struct WebNotificationCenterPrivate {

    MappedObservers m_mappedObservers;

};

// WebNotificationCenter ----------------------------------------------------------------

IWebNotificationCenter* WebNotificationCenter::m_defaultCenter = 0;

WebNotificationCenter::WebNotificationCenter()

    : m_refCount(0)

    , d(new WebNotificationCenterPrivate)

{

    gClassCount++;

    gClassNameCount.add("WebNotificationCenter");

}

WebNotificationCenter::~WebNotificationCenter()

{

    gClassCount--;

    gClassNameCount.remove("WebNotificationCenter");

}

WebNotificationCenter* WebNotificationCenter::createInstance()

{

    WebNotificationCenter* instance = new WebNotificationCenter();

    instance->AddRef();

    return instance;

}

// IUnknown -------------------------------------------------------------------

HRESULT STDMETHODCALLTYPE WebNotificationCenter::QueryInterface(REFIID riid, void** ppvObject)

{

    *ppvObject = 0;

    if (IsEqualGUID(riid, IID_IUnknown))

        *ppvObject = static_cast<IWebNotificationCenter*>(this);

    else if (IsEqualGUID(riid, IID_IWebNotificationCenter))

        *ppvObject = static_cast<IWebNotificationCenter*>(this);

    else

        return E_NOINTERFACE;

    AddRef();

    return S_OK;

}

ULONG STDMETHODCALLTYPE WebNotificationCenter::AddRef(void)

{

    return ++m_refCount;

}

ULONG STDMETHODCALLTYPE WebNotificationCenter::Release(void)

{

    ULONG newRef = --m_refCount;

    if (!newRef)

        delete(this);

    return newRef;

}

IWebNotificationCenter* WebNotificationCenter::defaultCenterInternal()

{

    if (!m_defaultCenter)

        m_defaultCenter = WebNotificationCenter::createInstance();

    return m_defaultCenter;

}

void WebNotificationCenter::postNotificationInternal(IWebNotification* notification, BSTR notificationName, IUnknown* anObject)

{

    String name(notificationName, SysStringLen(notificationName));

    MappedObservers::iterator it = d->m_mappedObservers.find(name);

    if (it == d->m_mappedObservers.end())

        return;

    // Intentionally make a copy of the list to avoid the possibility of errors

    // from a mutation of the list in the onNotify callback.

    ObjectObserverList list = it->second;

    ObserverListIterator end = list.end();

    for (ObserverListIterator it2 = list.begin(); it2 != end; ++it2) {

        IUnknown* observedObject = it2->first.get();

        IWebNotificationObserver* observer = it2->second.get();

        if (!observedObject || !anObject || observedObject == anObject)

            observer->onNotify(notification);

    }

}

// IWebNotificationCenter -----------------------------------------------------

HRESULT STDMETHODCALLTYPE WebNotificationCenter::defaultCenter( 

    /* [retval][out] */ IWebNotificationCenter** center)

{

    *center = defaultCenterInternal();

    (*center)->AddRef();

    return S_OK;

}

HRESULT STDMETHODCALLTYPE WebNotificationCenter::addObserver( 

    /* [in] */ IWebNotificationObserver* observer,

    /* [in] */ BSTR notificationName,

    /* [in] */ IUnknown* anObject)

{

    String name(notificationName, SysStringLen(notificationName));

    MappedObservers::iterator it = d->m_mappedObservers.find(name);

    if (it != d->m_mappedObservers.end())

        it->second.append(ObjectObserverPair(anObject, observer));

    else {

        ObjectObserverList list;

        list.append(ObjectObserverPair(anObject, observer));

        d->m_mappedObservers.add(name, list);

    }

    return S_OK;

}

HRESULT STDMETHODCALLTYPE WebNotificationCenter::postNotification( 

    /* [in] */ IWebNotification* notification)

{

    BSTR name;

    HRESULT hr = notification->name(&name);

    if (FAILED(hr))

        return hr;

    COMPtr<IUnknown> obj;

    hr = notification->getObject(&obj);

    if (FAILED(hr))

        return hr;

    postNotificationInternal(notification, name, obj.get());

    SysFreeString(name);

    return hr;

}

HRESULT STDMETHODCALLTYPE WebNotificationCenter::postNotificationName( 

    /* [in] */ BSTR notificationName,

    /* [in] */ IUnknown* anObject,

    /* [optional][in] */ IPropertyBag* userInfo)

{

    COMPtr<WebNotification> notification(AdoptCOM, WebNotification::createInstance(notificationName, anObject, userInfo));

    postNotificationInternal(notification.get(), notificationName, anObject);

    return S_OK;

}

HRESULT STDMETHODCALLTYPE WebNotificationCenter::removeObserver( 

    /* [in] */ IWebNotificationObserver* anObserver,

    /* [in] */ BSTR notificationName,

    /* [optional][in] */ IUnknown* anObject)

{

    String name(notificationName, SysStringLen(notificationName));

    MappedObservers::iterator it = d->m_mappedObservers.find(name);

    if (it == d->m_mappedObservers.end())

        return E_FAIL;

    ObjectObserverList& observerList = it->second;

    ObserverListIterator end = observerList.end();

    int i = 0;

    for (ObserverListIterator it2 = observerList.begin(); it2 != end; ++it2, ++i) {

        IUnknown* observedObject = it2->first.get();

        IWebNotificationObserver* observer = it2->second.get();

        if (observer == anObserver && (!anObject || anObject == observedObject)) {

            observerList.remove(i);

            break;

        }

    }

    if (observerList.isEmpty())

        d->m_mappedObservers.remove(name);

    return S_OK;

}