path: root/embed/mozilla/EphyBrowser.cpp

/*
 *  Copyright (C) 2000-2004 Marco Pesenti Gritti
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 *  $Id$
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "EphyBrowser.h"
#include "EphyUtils.h"
#include "MozillaPrivate.h"
#include "ephy-embed.h"
#include "ephy-string.h"
#include "ephy-debug.h"
#include "print-dialog.h"

#include <gtkmozembed_internal.h>
#include <unistd.h>

#include "nsIInterfaceRequestorUtils.h"
#include "nsIURI.h"
#include "nsISimpleEnumerator.h"

#include "nsIContentViewer.h"
#include "nsIWebBrowserFind.h"
#include "nsIWebBrowserFocus.h"
#include "nsICommandManager.h"
#include "nsIWebBrowserPrint.h"
#include "nsIDocCharset.h"
#include "nsIDocShellTreeItem.h"
#include "nsIDocShellTreeNode.h"
#include "nsIDocShellTreeOwner.h"
#include "nsIWebPageDescriptor.h"
#include "nsISHEntry.h"
#include "nsIHistoryEntry.h"
#include "nsIDOMHTMLDocument.h"
#include "nsIDOMHTMLCollection.h"
#include "nsIDOMHTMLElement.h"
#include "nsIDOMHTMLFormElement.h"
#include "nsIDOMHTMLInputElement.h"
#include "nsIDOMHTMLTextAreaElement.h"
#include "nsIDOMDocument.h"
#include "nsIDOM3Document.h"
#include "nsIDOMEvent.h"
#include "nsIDOMEventTarget.h"
#include "nsIDOMPopupBlockedEvent.h"
#include "nsIDOMNode.h"
#include "nsIDOMElement.h"
#include "nsIDOMWindow2.h"
#include "nsEmbedString.h"
#include "nsMemory.h"

#ifdef ALLOW_PRIVATE_API
#include "nsIMarkupDocumentViewer.h"
#endif

static PRUnichar DOMLinkAdded[] = { 'D', 'O', 'M', 'L', 'i', 'n', 'k',
                    'A', 'd', 'd', 'e', 'd', '\0' };
static PRUnichar DOMPopupBlocked[] = { 'D', 'O', 'M', 'P', 'o', 'p',
                       'u', 'p', 'B', 'l', 'o', 'c',
                       'k', 'e', 'd', '\0' };

EphyEventListener::EphyEventListener(void)
: mOwner(nsnull)
{
    LOG ("EphyEventListener ctor (%p)", this)
}

EphyEventListener::~EphyEventListener()
{
    LOG ("EphyEventListener dtor (%p)", this)
}

NS_IMPL_ISUPPORTS1(EphyEventListener, nsIDOMEventListener)

nsresult
EphyEventListener::Init(EphyEmbed *aOwner)
{
    mOwner = aOwner;
    return NS_OK;
}

nsresult
EphyFaviconEventListener::HandleFaviconLink (nsIDOMNode *node)
{
    nsresult result;

    nsCOMPtr<nsIDOMElement> linkElement;
    linkElement = do_QueryInterface (node);
    if (!linkElement) return NS_ERROR_FAILURE;

    PRUnichar relAttr[] = { 'r', 'e', 'l', '\0' };
    nsEmbedString value;
    result = linkElement->GetAttribute (nsEmbedString(relAttr), value);
    if (NS_FAILED (result)) return NS_ERROR_FAILURE;

    nsEmbedCString rel;
    NS_UTF16ToCString (value, NS_CSTRING_ENCODING_UTF8, rel);   

    if (g_ascii_strcasecmp (rel.get(), "SHORTCUT ICON") == 0 ||
        g_ascii_strcasecmp (rel.get(), "ICON") == 0)
    {
        PRUnichar hrefAttr[] = { 'h', 'r', 'e', 'f', '\0' };
        nsEmbedString value;
        result = linkElement->GetAttribute (nsEmbedString (hrefAttr), value);
        if (NS_FAILED (result) || !value.Length()) return NS_ERROR_FAILURE;

        nsEmbedCString link;
        NS_UTF16ToCString (value, NS_CSTRING_ENCODING_UTF8, link);

        nsCOMPtr<nsIDOMDocument> domDoc;
        node->GetOwnerDocument(getter_AddRefs(domDoc));
        NS_ENSURE_TRUE (domDoc, NS_ERROR_FAILURE);

        nsCOMPtr<nsIDOM3Document> doc = do_QueryInterface (domDoc);
        NS_ENSURE_TRUE (doc, NS_ERROR_FAILURE);

        nsEmbedString spec;
        result = doc->GetDocumentURI (spec);
        NS_ENSURE_SUCCESS (result, result);

        nsCOMPtr<nsIURI> uri;
        result = EphyUtils::NewURI (getter_AddRefs(uri), spec);
        NS_ENSURE_SUCCESS (result, result);

        nsEmbedCString favicon_url;
        result = uri->Resolve (link, favicon_url);
        if (NS_FAILED (result)) return NS_ERROR_FAILURE;
        
        char *url = g_strdup (favicon_url.get());
        g_signal_emit_by_name (mOwner, "ge_favicon", url);
        g_free (url);
    }

    return NS_OK;
}   

NS_IMETHODIMP
EphyFaviconEventListener::HandleEvent(nsIDOMEvent* aDOMEvent)
{
    nsCOMPtr<nsIDOMEventTarget> eventTarget;

    aDOMEvent->GetTarget(getter_AddRefs(eventTarget));

    nsCOMPtr<nsIDOMNode> node = do_QueryInterface(eventTarget);
    NS_ENSURE_TRUE (node, NS_ERROR_FAILURE);

    HandleFaviconLink (node);

    return NS_OK;
}

NS_IMETHODIMP
EphyPopupBlockEventListener::HandleEvent (nsIDOMEvent * aDOMEvent)
{
    nsresult rv;

    NS_ENSURE_TRUE (mOwner != NULL, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOMPopupBlockedEvent> popupEvent =
        do_QueryInterface (aDOMEvent, &rv);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    nsCOMPtr<nsIURI> popupWindowURI;
    rv = popupEvent->GetPopupWindowURI (getter_AddRefs (popupWindowURI));
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);
    NS_ENSURE_SUCCESS (popupWindowURI != NULL, NS_ERROR_FAILURE);

    nsEmbedCString popupWindowURIString;
    rv = popupWindowURI->GetSpec (popupWindowURIString);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    nsEmbedString popupWindowFeatures;
    rv = popupEvent->GetPopupWindowFeatures (popupWindowFeatures);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    nsEmbedCString popupWindowFeaturesString;
    NS_UTF16ToCString (popupWindowFeatures,
               NS_CSTRING_ENCODING_UTF8,
               popupWindowFeaturesString);

    g_signal_emit_by_name(mOwner, "ge_popup_blocked",
                  popupWindowURIString.get(),
                  popupWindowFeaturesString.get());

    return NS_OK;
}

EphyBrowser::EphyBrowser ()
: mFaviconEventListener(nsnull)
, mPopupBlockEventListener(nsnull)
, mInitialized(PR_FALSE)
{
}

EphyBrowser::~EphyBrowser ()
{
}

nsresult EphyBrowser::Init (GtkMozEmbed *mozembed)
{
    nsresult rv;

    if (mInitialized) return NS_OK;

    gtk_moz_embed_get_nsIWebBrowser (mozembed,
                     getter_AddRefs(mWebBrowser));
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    mWebBrowser->GetContentDOMWindow (getter_AddRefs (mDOMWindow));
    NS_ENSURE_TRUE (mDOMWindow, NS_ERROR_FAILURE);

    /* This will instantiate an about:blank doc if necessary */
    nsCOMPtr<nsIDOMDocument> domDocument;
    rv = mDOMWindow->GetDocument (getter_AddRefs (domDocument));
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    mFaviconEventListener = new EphyFaviconEventListener();
    if (!mFaviconEventListener) return NS_ERROR_OUT_OF_MEMORY;

    rv = mFaviconEventListener->Init (EPHY_EMBED (mozembed));
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    mPopupBlockEventListener = new EphyPopupBlockEventListener();
    if (!mPopupBlockEventListener) return NS_ERROR_OUT_OF_MEMORY;

    rv = mPopupBlockEventListener->Init (EPHY_EMBED (mozembed));
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    rv = GetListener();
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    mInitialized = PR_TRUE;

    return AttachListeners();
}

nsresult
EphyBrowser::GetListener (void)
{
    if (mEventReceiver) return NS_ERROR_FAILURE;

    nsCOMPtr<nsIDOMWindow> domWindowExternal;
    mWebBrowser->GetContentDOMWindow (getter_AddRefs(domWindowExternal));
  
    nsCOMPtr<nsIDOMWindow2> domWindow (do_QueryInterface (domWindowExternal));
    NS_ENSURE_TRUE (domWindow, NS_ERROR_FAILURE);
    
    nsCOMPtr<nsIDOMEventTarget> rootWindow;
    domWindow->GetWindowRoot (getter_AddRefs(rootWindow));

    mEventReceiver = do_QueryInterface (rootWindow);
    NS_ENSURE_TRUE (mEventReceiver, NS_ERROR_FAILURE);

    return NS_OK;
}

nsresult
EphyBrowser::AttachListeners(void)
{
    nsresult rv;

    NS_ENSURE_TRUE (mEventReceiver, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOMEventTarget> target;
    target = do_QueryInterface (mEventReceiver);

    rv = target->AddEventListener(nsEmbedString(DOMLinkAdded),
                      mFaviconEventListener, PR_FALSE);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    rv = target->AddEventListener(nsEmbedString(DOMPopupBlocked),
                      mPopupBlockEventListener, PR_FALSE);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    return NS_OK;
}

nsresult
EphyBrowser::DetachListeners(void)
{
    nsresult rv;

    if (!mEventReceiver) return NS_OK;

    nsCOMPtr<nsIDOMEventTarget> target;
    target = do_QueryInterface (mEventReceiver);
    NS_ENSURE_TRUE (target, NS_ERROR_FAILURE);

    rv = target->RemoveEventListener(nsEmbedString(DOMLinkAdded),
                     mFaviconEventListener, PR_FALSE);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    rv = target->RemoveEventListener(nsEmbedString(DOMPopupBlocked),
                     mPopupBlockEventListener, PR_FALSE);

    return NS_OK;
}

nsresult EphyBrowser::Print ()
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebBrowserPrint> print(do_GetInterface(mWebBrowser));
    NS_ENSURE_TRUE (print, NS_ERROR_FAILURE);

    return  print->Print (nsnull, nsnull);
}

nsresult EphyBrowser::SetPrintPreviewMode (PRBool previewMode)
{
    nsresult rv;

    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebBrowserPrint> print(do_GetInterface(mWebBrowser));
    NS_ENSURE_TRUE (print, NS_ERROR_FAILURE);

    if (previewMode)
    {
        EmbedPrintInfo *info;

        nsCOMPtr<nsIPrintSettings> settings;
        print->GetGlobalPrintSettings (getter_AddRefs(settings));

        info = ephy_print_get_print_info ();
        MozillaCollatePrintSettings (info, settings, TRUE);
        ephy_print_info_free (info);

        rv = print->PrintPreview (nsnull, mDOMWindow, nsnull);
    }
    else
    {
        PRBool isPreview = PR_FALSE;

        rv = print->GetDoingPrintPreview(&isPreview);
        NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

        if (isPreview == PR_TRUE)
        {
            rv = print->ExitPrintPreview();
        }
    }

    return rv;
}

nsresult EphyBrowser::PrintPreviewNumPages (int *numPages)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebBrowserPrint> print(do_GetInterface(mWebBrowser));
    NS_ENSURE_TRUE (print, NS_ERROR_FAILURE);

    return print->GetPrintPreviewNumPages(numPages);
}

nsresult EphyBrowser::PrintPreviewNavigate(PRInt16 navType, PRInt32 pageNum)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebBrowserPrint> print(do_GetInterface(mWebBrowser));
    NS_ENSURE_TRUE (print, NS_ERROR_FAILURE);

    return print->PrintPreviewNavigate(navType, pageNum);
}

nsresult EphyBrowser::GetSHistory (nsISHistory **aSHistory)
{
    nsresult result;

    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebNavigation> ContentNav = do_QueryInterface (mWebBrowser);
    NS_ENSURE_TRUE (ContentNav, NS_ERROR_FAILURE);

    nsCOMPtr<nsISHistory> SessionHistory;
    result = ContentNav->GetSessionHistory (getter_AddRefs (SessionHistory));
    NS_ENSURE_TRUE (SessionHistory, NS_ERROR_FAILURE);

    *aSHistory = SessionHistory.get();
    NS_IF_ADDREF (*aSHistory);

    return NS_OK;
}

nsresult EphyBrowser::Destroy ()
{
    DetachListeners ();

        mWebBrowser = nsnull;
    mDOMWindow = nsnull;
    mEventReceiver = nsnull;

    mInitialized = PR_FALSE;

    return NS_OK;
}

nsresult EphyBrowser::GoToHistoryIndex (PRInt16 index)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebNavigation> ContentNav = do_QueryInterface (mWebBrowser);
    NS_ENSURE_TRUE (ContentNav, NS_ERROR_FAILURE);

    return ContentNav->GotoIndex (index);
}

/* Workaround for broken reload with frames, see mozilla bug
 * http://bugzilla.mozilla.org/show_bug.cgi?id=246392
 */
nsresult EphyBrowser::Reload (PRUint32 flags)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsISHistory> sessionHistory;
    GetSHistory (getter_AddRefs (sessionHistory));

    nsCOMPtr<nsIWebNavigation> webNavigation;
    webNavigation = do_QueryInterface (sessionHistory);

    if (!webNavigation)
    {
        webNavigation = do_QueryInterface (mWebBrowser);
    }
    NS_ENSURE_TRUE (webNavigation, NS_ERROR_FAILURE);

    PRUint32 reloadFlags;
    switch (flags)
    {
        case RELOAD_FORCE:
            reloadFlags = nsIWebNavigation::LOAD_FLAGS_BYPASS_CACHE | 
                      nsIWebNavigation::LOAD_FLAGS_BYPASS_PROXY;
            break;
        case RELOAD_ENCODING_CHANGE:
            reloadFlags = nsIWebNavigation::LOAD_FLAGS_CHARSET_CHANGE;
            break;
        case RELOAD_NORMAL:
        default:
            reloadFlags = 0;
            break;
    }

    return webNavigation->Reload (reloadFlags);
}

nsresult EphyBrowser::SetZoom (float aZoom)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIContentViewer> contentViewer;   
    GetContentViewer (getter_AddRefs(contentViewer));
    NS_ENSURE_TRUE (contentViewer, NS_ERROR_FAILURE);

    nsCOMPtr<nsIMarkupDocumentViewer> mdv = do_QueryInterface(contentViewer);
    NS_ENSURE_TRUE (mdv, NS_ERROR_FAILURE);

    return mdv->SetTextZoom (aZoom);
}

nsresult EphyBrowser::GetContentViewer (nsIContentViewer **aViewer)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDocShell> ourDocShell(do_GetInterface(mWebBrowser));
    NS_ENSURE_TRUE (ourDocShell, NS_ERROR_FAILURE);

    return ourDocShell->GetContentViewer(aViewer);
}

nsresult EphyBrowser::GetZoom (float *aZoom)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIContentViewer> contentViewer;   
    GetContentViewer (getter_AddRefs(contentViewer));
    NS_ENSURE_TRUE (contentViewer, NS_ERROR_FAILURE);

    nsCOMPtr<nsIMarkupDocumentViewer> mdv = do_QueryInterface(contentViewer);
    NS_ENSURE_TRUE (mdv, NS_ERROR_FAILURE);

    return mdv->GetTextZoom (aZoom);
}

nsresult EphyBrowser::GetDocument (nsIDOMDocument **aDOMDocument)
{
    return mDOMWindow->GetDocument (aDOMDocument);
}

nsresult EphyBrowser::GetTargetDocument (nsIDOMDocument **aDOMDocument)
{
    nsresult result;

    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    /* Use the current target document */
    if (mTargetDocument)
    {
        *aDOMDocument = mTargetDocument.get();

        NS_IF_ADDREF(*aDOMDocument);

        return NS_OK;
    }

    /* Use the focused document */
    nsCOMPtr<nsIWebBrowserFocus> webBrowserFocus;
    webBrowserFocus = do_QueryInterface (mWebBrowser);
    NS_ENSURE_TRUE (webBrowserFocus, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOMWindow> DOMWindow;
    result = webBrowserFocus->GetFocusedWindow (getter_AddRefs(DOMWindow));
    if (NS_SUCCEEDED(result) && DOMWindow)
    {
        return DOMWindow->GetDocument (aDOMDocument);
    }

    /* Use the main document */
    return mDOMWindow->GetDocument (aDOMDocument);
}

nsresult EphyBrowser::GetSHInfo (PRInt32 *count, PRInt32 *index)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsISHistory> SessionHistory;
    GetSHistory (getter_AddRefs(SessionHistory));
    NS_ENSURE_TRUE (SessionHistory, NS_ERROR_FAILURE);

    SessionHistory->GetCount (count);
    SessionHistory->GetIndex (index);   

    return NS_OK;
}

nsresult EphyBrowser::GetSHTitleAtIndex (PRInt32 index, PRUnichar **title)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsISHistory> SessionHistory;
    GetSHistory (getter_AddRefs(SessionHistory));
    NS_ENSURE_TRUE (SessionHistory, NS_ERROR_FAILURE);

    nsCOMPtr<nsIHistoryEntry> he;
    SessionHistory->GetEntryAtIndex (index, PR_FALSE,
                     getter_AddRefs (he));
    NS_ENSURE_TRUE (he, NS_ERROR_FAILURE);

    nsresult result;
    result = he->GetTitle (title);
    NS_ENSURE_TRUE (NS_SUCCEEDED (result) && title, NS_ERROR_FAILURE);

    return NS_OK;
}

nsresult EphyBrowser::GetSHUrlAtIndex (PRInt32 index, nsACString &url)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsISHistory> SessionHistory;
    GetSHistory (getter_AddRefs(SessionHistory));
    NS_ENSURE_TRUE (SessionHistory, NS_ERROR_FAILURE);

    nsCOMPtr<nsIHistoryEntry> he;
    SessionHistory->GetEntryAtIndex (index, PR_FALSE,
                     getter_AddRefs (he));
    NS_ENSURE_TRUE (he, NS_ERROR_FAILURE);

    nsCOMPtr<nsIURI> uri;
    he->GetURI (getter_AddRefs(uri));
    NS_ENSURE_TRUE (uri, NS_ERROR_FAILURE);

    nsresult result;
    result = uri->GetSpec(url);
    NS_ENSURE_TRUE (NS_SUCCEEDED (result) && url.Length(), NS_ERROR_FAILURE);

    return NS_OK;
}

nsresult EphyBrowser::FindSetProperties (const PRUnichar *search_string,
                             PRBool case_sensitive,
                     PRBool wrap_around)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebBrowserFind> finder (do_GetInterface(mWebBrowser));
    NS_ENSURE_TRUE (finder, NS_ERROR_FAILURE);

    finder->SetSearchString (search_string);
    finder->SetMatchCase (case_sensitive);
    finder->SetWrapFind (wrap_around);

    return NS_OK;
}

nsresult EphyBrowser::Find (PRBool backwards,
                PRBool *didFind)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebBrowserFind> finder (do_GetInterface(mWebBrowser));
    NS_ENSURE_TRUE (finder, NS_ERROR_FAILURE);

    finder->SetFindBackwards (backwards);

    return finder->FindNext(didFind);
}

nsresult EphyBrowser::GetPageDescriptor(nsISupports **aPageDescriptor)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDocShell> ds = do_GetInterface (mWebBrowser);

    nsCOMPtr<nsIWebPageDescriptor> wpd = do_QueryInterface (ds);
    NS_ENSURE_TRUE (wpd, NS_ERROR_FAILURE);

    *aPageDescriptor = wpd.get();
    NS_IF_ADDREF (*aPageDescriptor);

    return NS_OK;
}

nsresult EphyBrowser::GetDOMWindow (nsIDOMWindow **aDOMWindow)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    NS_IF_ADDREF (*aDOMWindow = mDOMWindow);

    return NS_OK;
}

nsresult EphyBrowser::GetDocumentUrl (nsACString &url)
{
    nsresult rv;

    NS_ENSURE_TRUE (mDOMWindow, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOMDocument> DOMDocument;
    mDOMWindow->GetDocument (getter_AddRefs(DOMDocument));
    NS_ENSURE_TRUE (DOMDocument, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOM3Document> doc = do_QueryInterface(DOMDocument);
    NS_ENSURE_TRUE (doc, NS_ERROR_FAILURE);

    nsEmbedString docURI;
    rv = doc->GetDocumentURI (docURI);
    NS_ENSURE_SUCCESS (rv, rv);

    NS_UTF16ToCString (docURI, NS_CSTRING_ENCODING_UTF8, url);

    return NS_OK;
}

nsresult EphyBrowser::GetTargetDocumentUrl (nsACString &url)
{
    nsresult rv;

    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

        nsCOMPtr<nsIDOMDocument> DOMDocument;
    GetTargetDocument (getter_AddRefs(DOMDocument));
    NS_ENSURE_TRUE (DOMDocument, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOM3Document> doc = do_QueryInterface(DOMDocument);
    NS_ENSURE_TRUE (doc, NS_ERROR_FAILURE);

    nsEmbedString docURI;
    rv = doc->GetDocumentURI (docURI);
    NS_ENSURE_SUCCESS (rv, rv);

    NS_UTF16ToCString (docURI, NS_CSTRING_ENCODING_UTF8, url);

    return NS_OK;
}

nsresult EphyBrowser::ForceEncoding (const char *encoding) 
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIContentViewer> contentViewer;   
    GetContentViewer (getter_AddRefs(contentViewer));
    NS_ENSURE_TRUE (contentViewer, NS_ERROR_FAILURE);

    nsCOMPtr<nsIMarkupDocumentViewer> mdv = do_QueryInterface(contentViewer);
    NS_ENSURE_TRUE (mdv, NS_ERROR_FAILURE);

    return mdv->SetForceCharacterSet (nsEmbedCString(encoding));
}

nsresult EphyBrowser::GetEncoding (nsACString &encoding)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDocCharset> docCharset = do_GetInterface (mWebBrowser);
    NS_ENSURE_TRUE (docCharset, NS_ERROR_FAILURE);

    char *charset;
    docCharset->GetCharset (&charset);
    encoding = charset;
    nsMemory::Free (charset);

    return NS_OK;
}

nsresult EphyBrowser::GetForcedEncoding (nsACString &encoding)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIContentViewer> contentViewer;   
    GetContentViewer (getter_AddRefs(contentViewer));
    NS_ENSURE_TRUE (contentViewer, NS_ERROR_FAILURE);

    nsCOMPtr<nsIMarkupDocumentViewer> mdv = do_QueryInterface(contentViewer);
    NS_ENSURE_TRUE (mdv, NS_ERROR_FAILURE);

    nsresult result = mdv->GetForceCharacterSet (encoding);
    NS_ENSURE_SUCCESS (result, NS_ERROR_FAILURE);

    return NS_OK;
}

nsresult EphyBrowser::PushTargetDocument (nsIDOMDocument *domDoc)
{
    mTargetDocument = domDoc;

    return NS_OK;
}

nsresult EphyBrowser::PopTargetDocument ()
{
    mTargetDocument = nsnull;

    return NS_OK;
}

nsresult EphyBrowser::DoCommand (const char *command)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsICommandManager> cmdManager;
    cmdManager = do_GetInterface (mWebBrowser);
    NS_ENSURE_TRUE (cmdManager, NS_ERROR_FAILURE);

    return cmdManager->DoCommand (command, nsnull, nsnull);
}

nsresult EphyBrowser::GetCommandState (const char *command, PRBool *enabled)
{
    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsICommandManager> cmdManager;
    cmdManager = do_GetInterface (mWebBrowser);
    NS_ENSURE_TRUE (cmdManager, NS_ERROR_FAILURE);

    return cmdManager->IsCommandEnabled (command, nsnull, enabled);
}

#define NUM_MODIFIED_TEXTFIELDS_REQUIRED    2

PRBool
EphyBrowser::CompareFormsText (nsAString &aDefaultText, nsAString &aUserText)
{
    if (aDefaultText.Length() != aUserText.Length())
    {
        return FALSE;
    }

    /* Mozilla Bug 218277, 195946 and others */
    const PRUnichar *text = aDefaultText.BeginReading();
    for (PRUint32 i = 0; i < aDefaultText.Length(); i++)
    {
        if (text[i] == 0xa0)
        {
            aDefaultText.Replace (i, 1, ' ');
        }
    }

    return (memcmp (aDefaultText.BeginReading(),
                aUserText.BeginReading(),
                aUserText.Length() * sizeof (PRUnichar)) == 0);
}

nsresult EphyBrowser::GetDocumentHasModifiedForms (nsIDOMDocument *aDomDoc, PRUint32 *aNumTextFields, PRBool *aHasTextArea)
{
    nsCOMPtr<nsIDOMHTMLDocument> htmlDoc = do_QueryInterface(aDomDoc);
    /* it's okay not to be a HTML doc (happens for XUL documents, like about:config) */
    if (!htmlDoc) return NS_OK;

    nsCOMPtr<nsIDOMHTMLCollection> forms;
    htmlDoc->GetForms (getter_AddRefs (forms));
    if (!forms) return NS_OK; /* it's ok not to have any forms */

    PRUint32 formNum;
    forms->GetLength (&formNum);

    /* check all forms */
    for (PRUint32 formIndex = 0; formIndex < formNum; formIndex++)
    {
        nsCOMPtr<nsIDOMNode> formNode;
        forms->Item (formIndex, getter_AddRefs (formNode));
        if (!formNode) continue;

        nsCOMPtr<nsIDOMHTMLFormElement> formElement = do_QueryInterface (formNode);
        if (!formElement) continue;

        nsCOMPtr<nsIDOMHTMLCollection> formElements;
        formElement->GetElements (getter_AddRefs (formElements));
        if (!formElements) continue;

        PRUint32 elementNum;
        formElements->GetLength (&elementNum);

        /* check all input elements in the form for user input */
        for (PRUint32 elementIndex = 0; elementIndex < elementNum; elementIndex++)
        {
            nsCOMPtr<nsIDOMNode> domNode;
            formElements->Item (elementIndex, getter_AddRefs (domNode));
            if (!domNode) continue;

            nsCOMPtr<nsIDOMHTMLTextAreaElement> areaElement = do_QueryInterface (domNode);
            if (areaElement)
            {
                nsEmbedString defaultText, userText;
                areaElement->GetDefaultValue (defaultText);
                areaElement->GetValue (userText);

                if (!CompareFormsText (defaultText, userText))
                {
                    *aHasTextArea = PR_TRUE;
                    return NS_OK;
                }

                continue;
            }

            nsCOMPtr<nsIDOMHTMLInputElement> inputElement = do_QueryInterface(domNode);
            if (!inputElement) continue;
    
            nsEmbedString type;
            inputElement->GetType(type);

            nsEmbedCString cType;
            NS_UTF16ToCString (type, NS_CSTRING_ENCODING_UTF8, cType);

            if (g_ascii_strcasecmp (cType.get(), "text") == 0)
            {
                nsEmbedString defaultText, userText;
                PRInt32 max_length;
                inputElement->GetDefaultValue (defaultText);
                inputElement->GetValue (userText);
                inputElement->GetMaxLength (&max_length);

                /* There are forms for which defaultValue is longer than
                 * userValue. Mozilla consider this not a bug [see WONTFIXed
                 * bug 232057], but we need to check for this here.
                 */
                if (defaultText.Length() > (PRUint32)max_length)
                {
                    defaultText.Cut (max_length, PR_UINT32_MAX);
                }

                if (!CompareFormsText (defaultText, userText))
                {
                    (*aNumTextFields)++;
                    if (*aNumTextFields >= NUM_MODIFIED_TEXTFIELDS_REQUIRED)
                    {
                        return NS_OK;
                    }
                }
            }
        }
    }

    return NS_OK;
}

nsresult EphyBrowser::GetHasModifiedForms (PRBool *modified)
{
    *modified = PR_FALSE;

    NS_ENSURE_TRUE (mWebBrowser, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDocShell> rootDocShell = do_GetInterface (mWebBrowser);
    NS_ENSURE_TRUE (rootDocShell, NS_ERROR_FAILURE);

    nsCOMPtr<nsISimpleEnumerator> enumerator;
    rootDocShell->GetDocShellEnumerator(nsIDocShellTreeItem::typeContent,
                        nsIDocShell::ENUMERATE_FORWARDS,
                        getter_AddRefs(enumerator));
    NS_ENSURE_TRUE (enumerator, NS_ERROR_FAILURE);

    PRBool hasMore;
    PRBool hasTextArea = PR_FALSE;
    PRUint32 numTextFields = 0;
    while (NS_SUCCEEDED(enumerator->HasMoreElements(&hasMore)) && hasMore)
    {
        nsCOMPtr<nsISupports> element;
        enumerator->GetNext (getter_AddRefs(element));
        if (!element) continue;

        nsCOMPtr<nsIDocShell> docShell = do_QueryInterface (element);
        if (!docShell) continue;

        nsCOMPtr<nsIContentViewer> contentViewer;
        docShell->GetContentViewer (getter_AddRefs(contentViewer));
        if (!contentViewer) continue;

        nsCOMPtr<nsIDOMDocument> domDoc;
        contentViewer->GetDOMDocument (getter_AddRefs (domDoc));

        nsresult result;
        result = GetDocumentHasModifiedForms (domDoc, &numTextFields, &hasTextArea);
        if (NS_SUCCEEDED (result) &&
            (numTextFields >= NUM_MODIFIED_TEXTFIELDS_REQUIRED || hasTextArea))
        {
            *modified = PR_TRUE;
            break;
        }
    }

    return NS_OK;
}