source: trunk/third/mozilla/xpfe/bootstrap/nsDocLoadObserver.cpp @ 19518

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: NPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Netscape 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/NPL/
 *
 * 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 Mozilla Communicator client code.
 *
 * The Initial Developer of the Original Code is 
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *  Simon Fraser <sfraser@netscape.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or 
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the NPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the NPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#include "nsCOMPtr.h"
#include "nsError.h"
#include "nsIObserverService.h"
#include "nsIServiceManager.h"
#include "nsString.h"
#include "nsReadableUtils.h"
#include "nsAEUtils.h"
#include "nsAESpyglassSuiteHandler.h"

#include "nsDocLoadObserver.h"

nsDocLoadObserver::nsDocLoadObserver()
:       mRegistered(PR_FALSE)
{
}

nsDocLoadObserver::~nsDocLoadObserver()
{
}


NS_IMPL_ISUPPORTS1(nsDocLoadObserver, nsIObserver)

void nsDocLoadObserver::Register()
{
        if (!mRegistered)
        {
                nsresult rv;
                nsCOMPtr<nsIObserverService> anObserverService = do_GetService("@mozilla.org/observer-service;1", &rv);
                if (NS_SUCCEEDED(rv))
                {
                        if (NS_SUCCEEDED(anObserverService->AddObserver(this, "EndDocumentLoad", PR_FALSE)))
                        {
                                mRegistered = PR_TRUE;
                        }
                }
        }
}

void nsDocLoadObserver::Unregister()
{
        if (mRegistered)
        {
                nsresult rv;
                nsCOMPtr<nsIObserverService> anObserverService = do_GetService("@mozilla.org/observer-service;1", &rv);
                if (NS_SUCCEEDED(rv))
                {
                        if (NS_SUCCEEDED(anObserverService->RemoveObserver(this, 
                                "EndDocumentLoad")))
                        {
                                mRegistered = PR_FALSE;
                        }
                }
        }
}

void nsDocLoadObserver::AddEchoRequester(OSType appSignature)
{
  // make sure an application is only in the list once
  mEchoRequesters.RemoveElement((void*)appSignature);
  
        mEchoRequesters.AppendElement((void*)appSignature);
        Register();     // ensure we are registered
}

void nsDocLoadObserver::RemoveEchoRequester(OSType appSignature)
{
        mEchoRequesters.RemoveElement((void*)appSignature);
        if (mEchoRequesters.Count() == 0)
          Unregister();
}

NS_IMETHODIMP nsDocLoadObserver::Observe(nsISupports* /*aSubject*/,
                const char* /*aTopic*/, const PRUnichar* someData)
{
        // we need a URL to forward
        if (!someData)
                return NS_ERROR_NULL_POINTER;

        // are there any echo requesters to notify?
        if (mEchoRequesters.Count() == 0)
                return NS_OK;

        // create the descriptor for identifying this application
        StAEDesc from;
        const OSType mozz = 'MOZZ';
        if (noErr != ::AECreateDesc(typeType, &mozz, sizeof(mozz), &from))
                return NS_ERROR_UNEXPECTED;

        // create the descriptor for the URL
        nsString urlText(someData);
        char* urlString = ToNewCString(urlText);

        StAEDesc url;
        OSErr err = ::AECreateDesc(typeChar, urlString, urlText.Length(), &url);
        nsMemory::Free(urlString);
        if (err != noErr)
                return NS_ERROR_UNEXPECTED;

        // keep track of any invalid requesters and remove them when we're done
        nsVoidArray requestersToRemove;
        
        PRInt32         numRequesters = mEchoRequesters.Count();
        
        // now notify all the echo requesters
        for (PRInt32 i = 0; i < numRequesters; i ++)
        {
                // specify the address of the requester
                StAEDesc targetAddress;
                const OSType target = (OSType)mEchoRequesters.ElementAt(i);
                if (noErr != ::AECreateDesc(typeApplSignature, &target, sizeof(target), &targetAddress))
                        return NS_ERROR_UNEXPECTED;

                // create the event
                AppleEvent sendEvent;
                err = ::AECreateAppleEvent(AESpyglassSuiteHandler::kSpyglassSendSignature,
                                AESpyglassSuiteHandler::kSendURLEchoEvent, 
                                &targetAddress, kAutoGenerateReturnID, kAnyTransactionID, &sendEvent);
                if (noErr != err)
                {       // this target is no longer available
                        requestersToRemove.AppendElement((void *)target);
                        continue;
                }

                // attach our signature - to let the requester know who we are
                err = ::AEPutParamDesc(&sendEvent, keyOriginalAddressAttr, &from);
                NS_ASSERTION(noErr == err, "AEPutParamDesc");

                // attach the new URL
                err = ::AEPutParamDesc(&sendEvent, keyDirectObject, &url);
                NS_ASSERTION(noErr == err, "AEPutParamDesc");
                
                // send it
                AppleEvent reply;
                err = ::AESend(&sendEvent, &reply, kAENoReply, kAENormalPriority, 180, NULL, NULL);
                NS_ASSERTION(noErr == err, "AESend");
                ::AEDisposeDesc(&sendEvent);
        }

        // now remove unresponsive requestors
        for (PRInt32 i = 0; i < requestersToRemove.Count(); i ++)
        {
                OSType  thisRequester = (OSType)requestersToRemove.ElementAt(i);
                mEchoRequesters.RemoveElement((void *)thisRequester);
        }
        
        return NS_OK;
}