/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * The contents of this file are subject to the Mozilla Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/MPL/
 * 
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 * 
 * The Original Code is the Mozilla browser.
 * 
 * The Initial Developer of the Original Code is Netscape
 * Communications, Inc.  Portions created by Netscape are
 * Copyright (C) 1999, Mozilla.  All Rights Reserved.
 * 
 * Author:
 *   Adam Lock <adamlock@netscape.com>
 *
 * Contributor(s):
 */

#ifndef NSEMBEDAPI_H
#define NSEMBEDAPI_H

#include "nsILocalFile.h"
#include "nsIDirectoryService.h"

/**
 * @file
 * @brief The Gecko embedding API functions, structures and definitions.
 */

/**
 * @fn nsresult NS_InitEmbedding(nsILocalFile *aMozBinDirectory, nsIDirectoryServiceProvider *aAppFileLocProvider)
 *
 * Initialises the Gecko embedding layer. You <I>must</I>
 * call this method before proceeding to use Gecko. This function ensures
 * XPCOM is started, creates the component registry if necessary and
 * starts global services.
 *
 * @status FROZEN
 *
 * @note Use <CODE>NS_NewLocalFile</CODE> to create the file object you
 *       supply as the bin directory path in this call. The function
 *       may be safely called before the rest of XPCOM or embedding has
 *       been initialised.
 *
 * @param aMozBinDirectory The Gecko directory containing the component
 *                         registry and runtime libraries;
 *                         or use <CODE>nsnull</CODE> to use the working
 *                         directory.
 * @param aAppFileLocProvider The object to be used by Gecko that specifies
 *                         to Gecko where to find profiles, the component
 *                         registry preferences and so on; or use
 *                         <CODE>nsnull</CODE> for the default behaviour.
 *
 * @see NS_NewLocalFile
 * @see nsILocalFile
 * @see nsIDirectoryServiceProvider
 *
 * @return NS_OK for success;
 *         other error codes indicate a failure during initialisation.
 *
 */
extern nsresult NS_InitEmbedding(nsILocalFile *aMozBinDirectory,
                                 nsIDirectoryServiceProvider *aAppFileLocProvider);


/**
 * @fn nsresult NS_TermEmbedding()
 *
 * Terminates the Gecko embedding layer. Call this function during shutdown to
 * ensure that global services are unloaded, files are closed and
 * XPCOM is shutdown.
 *
 * @status FROZEN
 *
 * @note Release any XPCOM objects within Gecko that you may be holding a
 *       reference to before calling this function.
 *
 * @return NS_OK
 */
extern nsresult NS_TermEmbedding();

/*---------------------------------------------------------------------------*/
/* Event processing APIs. The native OS dependencies mean you must be        */
/* building on a supported platform to get the functions below.              */
/*---------------------------------------------------------------------------*/

#undef MOZ_SUPPORTS_EMBEDDING_EVENT_PROCESSING

/* Win32 specific stuff */
#ifdef WIN32
#include "windows.h"

/**
 * @var typedef MSG nsEmbedNativeEvent
 * 
 * Embedding events are native <CODE>MSG</CODE> structs on Win32.
 */
typedef MSG nsEmbedNativeEvent;
#define MOZ_SUPPORTS_EMBEDDING_EVENT_PROCESSING
#endif

/* Mac specific stuff */
/* TODO implementation left as an exercise for the reader */

/* GTK specific stuff */
/* TODO implementation left as an exercise for the reader */


#ifdef MOZ_SUPPORTS_EMBEDDING_EVENT_PROCESSING

/**
 * @fn nsresult NS_DoIdleEmbeddingStuff()
 *
 * This function should be called during the idle time in your application
 * or as each event is processed. This function ensures things such as
 * timers are fired correctly. It is recommended you call this function
 * even if has no perceived effect for your platform.
 *
 * @status UNDER_REVIEW
 *
 * @return NS_OK
 */
extern nsresult NS_DoIdleEmbeddingStuff();


/**
 * @fn nsresult NS_HandleEmbeddingEvent(nsEmbedNativeEvent &aEvent, PRBool &aWasHandled)
 *
 * This function gives Gecko the chance to process a native window events.
 * Call this function from your message processing loop.
 *
 * @status UNDER_REVIEW
 *
 * @param aEvent The native UI event
 * @param aWasHandled Returns with <CODE>PR_TRUE</CODE> if the end was
 *                    handled; in which case it should not be handled by your
 *                    application.
 *
 * @return NS_OK
 */
extern nsresult NS_HandleEmbeddingEvent(nsEmbedNativeEvent &aEvent, PRBool &aWasHandled);

#endif /* MOZ_SUPPORTS_EMBEDDING_EVENT_PROCESSING */

#endif /* NSEMBEDAPI_H */