/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** 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.org 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):
 *      Gagan Saksena (original author)
 *
 * 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 "nsAboutRedirector.h"
#include "nsNetCID.h"
#include "nsIIOService.h"
#include "nsIServiceManager.h"
#include "nsCOMPtr.h"
#include "nsIURI.h"
#include "nsXPIDLString.h"
#include "nsString.h"
#include "plstr.h"
#include "nsIScriptSecurityManager.h"

static NS_DEFINE_CID(kIOServiceCID, NS_IOSERVICE_CID);

NS_IMPL_ISUPPORTS1(nsAboutRedirector, nsIAboutModule)

struct RedirEntry {
    const char* id;
    const char* url;
    PRBool dropChromePrivs; // if PR_TRUE, the page will not have chrome privileges
};

// if you add something here, make sure you update the total
/*
  Entries with dropChromePrivs == PR_FALSE will run with chrome
  privileges. This is potentially dangerous. Please use PR_TRUE
  as the third argument to each map item below unless your about:
  page really needs chrome privileges. Security review is required
  before adding new map entries with dropChromePrivs == PR_FALSE.
 */
static RedirEntry kRedirMap[] = {
    { "credits", "http://www.mozilla.org/credits/", PR_TRUE },
    { "mozilla", "chrome://global/content/mozilla.xhtml", PR_TRUE },
    { "plugins", "chrome://global/content/plugins.html", PR_TRUE },
    { "config", "chrome://global/content/config.xul", PR_FALSE }
};
static const int kRedirTotal = 4; // sizeof(kRedirMap)/sizeof(*kRedirMap)

NS_IMETHODIMP
nsAboutRedirector::NewChannel(nsIURI *aURI, nsIChannel **result)
{
    NS_ENSURE_ARG(aURI);
    nsCAutoString path;
    (void)aURI->GetPath(path);
    nsresult rv;
    nsCOMPtr<nsIIOService> ioService(do_GetService(kIOServiceCID, &rv));
    if (NS_FAILED(rv))
        return rv;

    for (int i = 0; i< kRedirTotal; i++) 
    {
        if (!PL_strcasecmp(path.get(), kRedirMap[i].id))
        {
            nsCOMPtr<nsIChannel> tempChannel;
             rv = ioService->NewChannel(nsDependentCString(kRedirMap[i].url),
                                        nsnull, nsnull, getter_AddRefs(tempChannel));
             // Keep the page from getting unnecessary privileges unless it needs them
             if (NS_SUCCEEDED(rv) && result && kRedirMap[i].dropChromePrivs)
             {
                  nsCOMPtr<nsIScriptSecurityManager> securityManager = 
                           do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
                  if (NS_FAILED(rv))
                      return rv;
            
                  nsCOMPtr<nsIPrincipal> principal;
                  rv = securityManager->GetCodebasePrincipal(aURI, getter_AddRefs(principal));
                  if (NS_FAILED(rv))
                      return rv;
            
                  nsCOMPtr<nsISupports> owner = do_QueryInterface(principal);
                  rv = tempChannel->SetOwner(owner);
             }
             *result = tempChannel.get();
             NS_ADDREF(*result);
             return rv;
        }

    }
    NS_ASSERTION(0, "nsAboutRedirector called for unknown case");
    return NS_ERROR_ILLEGAL_VALUE;
}

NS_METHOD
nsAboutRedirector::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult)
{
    nsAboutRedirector* about = new nsAboutRedirector();
    if (about == nsnull)
        return NS_ERROR_OUT_OF_MEMORY;
    NS_ADDREF(about);
    nsresult rv = about->QueryInterface(aIID, aResult);
    NS_RELEASE(about);
    return rv;
}

////////////////////////////////////////////////////////////////////////////////
