path: root/embed/mozilla/EventContext.cpp

/*
 *  Copyright © 2000-2004 Marco Pesenti Gritti
 *  Copyright © 2003, 2004 Christian Persch
 *  Copyright © 2004 Crispin Flowerday
 *
 *  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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 *  $Id$
 */

#include "mozilla-config.h"
#include "config.h"

#include <gdk/gdkkeysyms.h>

#include <nsStringAPI.h>

#include <nsComponentManagerUtils.h>
#include <nsIDOM3Node.h>
#include <nsIDOMAbstractView.h>
#include <nsIDOMCharacterData.h>
#include <nsIDOMCSSPrimitiveValue.h>
#include <nsIDOMCSSStyleDeclaration.h>
#include <nsIDOMDocument.h>
#include <nsIDOMDocumentView.h>
#include <nsIDOMElementCSSInlineStyle.h>
#include <nsIDOMElement.h>
#include <nsIDOMEvent.h>
#include <nsIDOMEventTarget.h>
#include <nsIDOMEventTarget.h>
#include <nsIDOMHTMLAnchorElement.h>
#include <nsIDOMHTMLAreaElement.h>
#include <nsIDOMHTMLBodyElement.h>
#include <nsIDOMHTMLButtonElement.h>
#include <nsIDOMHTMLEmbedElement.h>
#include <nsIDOMHTMLImageElement.h>
#include <nsIDOMHTMLInputElement.h>
#include <nsIDOMHTMLIsIndexElement.h>
#include <nsIDOMHTMLLabelElement.h>
#include <nsIDOMHTMLLegendElement.h>
#include <nsIDOMHTMLMapElement.h>
#include <nsIDOMHTMLObjectElement.h>
#include <nsIDOMHTMLSelectElement.h>
#include <nsIDOMHTMLTextAreaElement.h>
#include <nsIDOMKeyEvent.h>
#include <nsIDOMMouseEvent.h>
#include <nsIDOMNode.h>
#include <nsIDOMNodeList.h>
#include <nsIDOMNSHTMLDocument.h>
#include <nsIDOMNSUIEvent.h>
#include <nsIInterfaceRequestor.h>
#include <nsIInterfaceRequestorUtils.h>
#include <nsIServiceManager.h>
#include <nsIURI.h>

#ifdef ALLOW_PRIVATE_API
#include <nsIDOMNSEvent.h>
#include <nsIDOMNSHTMLElement.h>
#include <nsIDOMViewCSS.h>
#include <nsIDOMViewCSS.h>
#include <nsIDOMXULDocument.h>
#include <nsITextToSubURI.h>
#endif

#include "ephy-debug.h"

#include "EphyBrowser.h"
#include "EphyUtils.h"

#include "EventContext.h"


#define KEY_CODE 256

EventContext::EventContext ()
{
    LOG ("EventContext ctor [%p]", this);
}

EventContext::~EventContext ()
{
    LOG ("EventContext dtor [%p]", this);
}

nsresult EventContext::Init (EphyBrowser *browser)
{
    mBrowser = browser;
    mDOMDocument = nsnull;

    return NS_OK;
}

nsresult EventContext::GatherTextUnder (nsIDOMNode* aNode, nsAString& aResult)
{
    nsString text;
    nsCOMPtr<nsIDOMNode> node;
    aNode->GetFirstChild(getter_AddRefs(node));
    PRUint32 depth = 1;

    while (node && depth)
    {
        nsCOMPtr<nsIDOMCharacterData> charData(do_QueryInterface(node));
        PRUint16 nodeType;

        node->GetNodeType(&nodeType);
        if (charData && nodeType == nsIDOMNode::TEXT_NODE)
        {
            /* Add this text to our collection. */
            text += ' ';
            nsString data;
            charData->GetData(data);
            text += data;
        }
        else
        {
            nsCOMPtr<nsIDOMHTMLImageElement> img(do_QueryInterface(node));
            if (img)
            {
                nsString altText;
                img->GetAlt(altText);
                if (altText.Length())
                {
                    text = altText;
                    break;
                }
            }
        }

        /* Find the next node to test. */
        PRBool hasChildNodes;
        node->HasChildNodes(&hasChildNodes);
        if (hasChildNodes)
        {
            nsCOMPtr<nsIDOMNode> temp = node;
            temp->GetFirstChild(getter_AddRefs(node));
            depth++;
        }
        else
        {
            nsCOMPtr<nsIDOMNode> nextSibling;
            node->GetNextSibling(getter_AddRefs(nextSibling));
            if (nextSibling)
            {
                node = nextSibling;
            }
            else
            {
                nsCOMPtr<nsIDOMNode> parentNode;
                node->GetParentNode(getter_AddRefs(parentNode));
                if (!parentNode)
                {
                    node = nsnull;
                }
                else
                {
                    parentNode->GetNextSibling(getter_AddRefs(nextSibling));
                    node = nextSibling;
                    depth--;
                }
            }
        }
    }

    /* FIXME we should trim spaces here */

    aResult = text;

    return NS_OK;
}

/* FIXME: we should resolve against the element's base, not the document's base */
nsresult EventContext::ResolveBaseURL (const nsAString &relurl, nsACString &url)
{
    nsCString cRelURL;
    NS_UTF16ToCString (relurl, NS_CSTRING_ENCODING_UTF8, cRelURL);  

    return mBaseURI->Resolve (cRelURL, url);
}

nsresult EventContext::Unescape (const nsACString &aEscaped, nsACString &aUnescaped)
{
    if (!aEscaped.Length()) return NS_ERROR_FAILURE;

    nsCOMPtr<nsITextToSubURI> escaper
        (do_CreateInstance ("@mozilla.org/intl/texttosuburi;1"));
    NS_ENSURE_TRUE (escaper, NS_ERROR_FAILURE);

    nsresult rv;
    nsCString encoding;
    rv = mBrowser->GetEncoding (encoding);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    nsString unescaped;
    rv = escaper->UnEscapeURIForUI (encoding, aEscaped, unescaped);
    NS_ENSURE_TRUE (NS_SUCCEEDED (rv) && unescaped.Length(), NS_ERROR_FAILURE);

    NS_UTF16ToCString (unescaped, NS_CSTRING_ENCODING_UTF8, aUnescaped);

    return NS_OK;
}

nsresult EventContext::GetEventContext (nsIDOMEventTarget *EventTarget,
                    MozillaEmbedEvent *info)
{
    nsresult rv;

    const PRUnichar hrefLiteral[] = {'h', 'r', 'e', 'f', '\0'};
    const PRUnichar imgLiteral[] = {'i', 'm', 'g', '\0'};
    const PRUnichar typeLiteral[] = {'t', 'y', 'p', 'e', '\0'};
    const PRUnichar xlinknsLiteral[] = {'h', 't', 't', 'p', ':', '/', '/','w',
                            'w', 'w', '.', 'w', '3', '.', 'o', 'r',
                            'g', '/', '1', '9', '9', '9', '/', 'x',
                            'l', 'i', 'n', 'k', '\0'};
    const PRUnichar bodyLiteral[] = { 'b', 'o', 'd', 'y', '\0' };

    mEmbedEvent = info;

    info->context = EPHY_EMBED_CONTEXT_DOCUMENT;

    nsCOMPtr<nsIDOMNode> node = do_QueryInterface(EventTarget, &rv);
    if (NS_FAILED(rv) || !node) return NS_ERROR_FAILURE;

        /* Is page xul ? then do not display context menus
     * FIXME I guess there is an easier way ... */
    /* From philipl: This test needs to be here otherwise we
     * arrogantly assume we can QI to a HTMLElement, which is
     * not true for xul content. */ 

    nsCOMPtr<nsIDOMDocument> domDoc;
    rv = node->GetOwnerDocument(getter_AddRefs(domDoc));
    if (NS_FAILED(rv) || !domDoc) return NS_ERROR_FAILURE;

    nsCOMPtr<nsIDOMXULDocument> xul_document = do_QueryInterface(domDoc);
    if (xul_document)
    {
        info->context = EPHY_EMBED_CONTEXT_NONE;
        return NS_ERROR_FAILURE;
    }

    mDOMDocument = domDoc;

    rv = mBrowser->GetEncoding (mCharset);
    NS_ENSURE_SUCCESS (rv, rv);

    /* Get base URI and CSS view */
    nsCOMPtr<nsIDOMDocumentView> docView (do_QueryInterface (domDoc));
    NS_ENSURE_TRUE (docView, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOMAbstractView> abstractView;
    docView->GetDefaultView (getter_AddRefs (abstractView));
    NS_ENSURE_TRUE (abstractView, NS_ERROR_FAILURE);
    /* the abstract view is really the DOM window */

    mViewCSS = do_QueryInterface (abstractView);
    NS_ENSURE_TRUE (mViewCSS, NS_ERROR_FAILURE);

    nsCOMPtr<nsIWebNavigation> webNav (do_GetInterface (abstractView, &rv));
    NS_ENSURE_SUCCESS (rv, rv);

    rv = webNav->GetCurrentURI (getter_AddRefs (mBaseURI));
    NS_ENSURE_SUCCESS (rv, rv);

    // Now we know that the page isn't a xul window, we can try and
    // do something useful with it.

    PRUint16 type;
    rv = node->GetNodeType(&type);
    if (NS_FAILED(rv)) return NS_ERROR_FAILURE;

    PRBool has_image = PR_FALSE;

    nsCOMPtr<nsIDOMHTMLElement> element = do_QueryInterface(node);
    if ((nsIDOMNode::ELEMENT_NODE == type) && element)
    {
        nsString uTag;
        rv = element->GetLocalName(uTag);
        if (NS_FAILED(rv)) return NS_ERROR_FAILURE;

        nsCString tag;
        NS_UTF16ToCString (uTag, NS_CSTRING_ENCODING_UTF8, tag);

        if (g_ascii_strcasecmp (tag.get(), "img") == 0)
        {
            nsString img;
            nsCOMPtr <nsIDOMHTMLImageElement> image = 
                        do_QueryInterface(node, &rv);
            if (NS_FAILED(rv) || !image) return NS_ERROR_FAILURE;           

            rv = image->GetSrc (img);
            if (NS_FAILED(rv)) return NS_ERROR_FAILURE;

            SetStringProperty ("image", img);
            info->context |= EPHY_EMBED_CONTEXT_IMAGE;
            has_image = PR_TRUE;
        }
        else if (g_ascii_strcasecmp (tag.get(), "area") == 0)
        {
            nsCOMPtr <nsIDOMHTMLAreaElement> area = 
                        do_QueryInterface(node, &rv);
            if (NS_FAILED(rv) || !area) return NS_ERROR_FAILURE;            

            // Parent node is the map itself
            nsCOMPtr<nsIDOMNode> parentNode;
            node->GetParentNode (getter_AddRefs(parentNode));

            nsCOMPtr <nsIDOMHTMLMapElement> map = 
                do_QueryInterface(parentNode, &rv);
            if (NS_FAILED(rv) || !area) return NS_ERROR_FAILURE;            

            nsString mapName;
            rv = map->GetName (mapName);
            if (NS_FAILED(rv)) return NS_ERROR_FAILURE;

            // Now we are searching for all the images with a usemap attribute
            nsCOMPtr<nsIDOMNodeList> imgs;
            rv = mDOMDocument->GetElementsByTagName (nsString(imgLiteral),  
                                 getter_AddRefs (imgs));
            if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
            
            PRUint32 imgs_count;
            rv = imgs->GetLength (&imgs_count);
            if (NS_FAILED (rv)) return NS_ERROR_FAILURE;

            for (PRUint32 i = 0; i < imgs_count; i++)
            {
                nsCOMPtr<nsIDOMNode> aNode;
                rv = imgs->Item (i, getter_AddRefs (aNode));
                if (NS_FAILED (rv)) continue;

                nsCOMPtr<nsIDOMHTMLImageElement> img = 
                        do_QueryInterface(aNode, &rv);
                if (NS_FAILED(rv) || !img) continue;
            
                nsString imgMapName;
                rv = img->GetUseMap (imgMapName);
                if (NS_FAILED (rv)) continue;

                // usemap always starts with #
                imgMapName.Cut (0,1);

                // Check if the current image is attached to the map we are looking for
                if (imgMapName.Equals(mapName))
                {
                    nsString imgSrc;
                    rv = img->GetSrc (imgSrc);
                    if (NS_FAILED(rv)) continue;

                    SetStringProperty ("image", imgSrc);
                    info->context |= EPHY_EMBED_CONTEXT_IMAGE;
                    has_image = PR_TRUE;

                    break;
                }
            }
        }
        else if (g_ascii_strcasecmp (tag.get(), "input") == 0)
        {
            CheckInput (node);
        }
        else if (g_ascii_strcasecmp (tag.get(), "textarea") == 0)
        {
            info->context |= EPHY_EMBED_CONTEXT_INPUT;
        }
        else if (g_ascii_strcasecmp (tag.get(), "object") == 0)
        {
            nsCOMPtr<nsIDOMHTMLObjectElement> object;
            object = do_QueryInterface (node);
            if (!element) return NS_ERROR_FAILURE;

            nsString value;
            object->GetType(value);

            nsCString cValue;
            NS_UTF16ToCString (value, NS_CSTRING_ENCODING_UTF8, cValue);

            // MIME types are always lower case
            if (g_str_has_prefix (cValue.get(), "image/"))
            {
                nsString img;
                
                rv = object->GetData (img);
                if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
                
                nsCString cImg;
                rv = ResolveBaseURL (img, cImg);
                                if (NS_FAILED (rv)) return NS_ERROR_FAILURE;

                SetStringProperty ("image", cImg.get());
                info->context |= EPHY_EMBED_CONTEXT_IMAGE;
                has_image = PR_TRUE;
            }
            else
            {
                info->context = EPHY_EMBED_CONTEXT_NONE;
                return NS_OK;
            }
        }
        else if (g_ascii_strcasecmp (tag.get(), "html") == 0)
        {
            /* Clicked on part of the page without a <body>, so
             * look for a background image in the body tag */
            nsCOMPtr<nsIDOMNodeList> nodeList;

            rv = mDOMDocument->GetElementsByTagName (nsString(bodyLiteral),
                                 getter_AddRefs (nodeList));
            if (NS_SUCCEEDED (rv) && nodeList)
            {
                nsCOMPtr<nsIDOMNode> bodyNode;
                nodeList->Item (0, getter_AddRefs (bodyNode));

                nsString cssurl;
                rv = GetCSSBackground (bodyNode, cssurl);
                if (NS_SUCCEEDED (rv))
                {
                    nsCString bgimg;
                    rv = ResolveBaseURL (cssurl, bgimg);
                    if (NS_FAILED (rv))
                        return NS_ERROR_FAILURE;

                    SetStringProperty ("image", bgimg.get());
                    info->context |= EPHY_EMBED_CONTEXT_IMAGE;
                    has_image = PR_TRUE;
                }
            }
        }
    }

    /* Is page framed ? */
    PRBool framed;
    IsPageFramed (node, &framed);
    SetIntProperty ("framed_page", framed);

    /* Bubble out, looking for items of interest */
    while (node)
    {
        nsCOMPtr <nsIDOMElement> dom_elem = do_QueryInterface(node);
        if (dom_elem)
        {
            nsString value;
            dom_elem->GetAttributeNS (nsString(xlinknsLiteral),
                          nsString(typeLiteral), value);

            nsCString cValue;
            NS_UTF16ToCString (value, NS_CSTRING_ENCODING_UTF8, cValue);

            if (g_ascii_strcasecmp (cValue.get(), "simple") == 0)
            {
                info->context |= EPHY_EMBED_CONTEXT_LINK;
                dom_elem->GetAttributeNS (nsString(xlinknsLiteral),
                              nsString(hrefLiteral), value);
                
                SetURIProperty (node, "link", value);
                CheckLinkScheme (value);
            }
        }

        rv = node->GetNodeType(&type);
        if (NS_FAILED(rv)) return NS_ERROR_FAILURE;

        element = do_QueryInterface(node);
        if ((nsIDOMNode::ELEMENT_NODE == type) && element)
        {
            nsString uTag;
            rv = element->GetLocalName(uTag);
            if (NS_FAILED(rv)) return NS_ERROR_FAILURE;

            nsCString tag;
            NS_UTF16ToCString (uTag, NS_CSTRING_ENCODING_UTF8, tag);

            /* Link */
            if (g_ascii_strcasecmp (tag.get(), "a") == 0)
            {
                nsString tmp;

                rv = GatherTextUnder (node, tmp);
                if (NS_SUCCEEDED(rv))
                                    SetStringProperty ("linktext", tmp);

                nsCOMPtr <nsIDOMHTMLAnchorElement> anchor =
                    do_QueryInterface(node);

                nsCString href;
                anchor->GetHref (tmp);
                NS_UTF16ToCString (tmp, NS_CSTRING_ENCODING_UTF8, href);

                if (g_str_has_prefix (href.get(), "mailto:"))
                {
                    /* cut "mailto:" */
                    href.Cut (0, 7);

                    char *str = g_strdup (href.get());
                    g_strdelimit (str, "?", '\0');

                    nsCString unescapedHref;
                    rv = Unescape (nsCString(str), unescapedHref);
                    if (NS_SUCCEEDED (rv) && unescapedHref.Length())
                    {
                        SetStringProperty ("email", unescapedHref.get());
                        info->context |= EPHY_EMBED_CONTEXT_EMAIL_LINK;
                    }
                    g_free (str);
                }
                
                if (anchor && tmp.Length()) 
                {
                    info->context |= EPHY_EMBED_CONTEXT_LINK;

                    SetURIProperty (node, "link", tmp);
                    CheckLinkScheme (tmp);
                    rv = anchor->GetHreflang (tmp);
                    if (NS_SUCCEEDED(rv))
                        SetStringProperty ("link_lang", tmp);
                    rv = anchor->GetTarget (tmp);
                    if (NS_SUCCEEDED(rv))
                        SetStringProperty ("link_target", tmp);
                    rv = anchor->GetRel (tmp);
                    if (NS_SUCCEEDED(rv))
                        SetStringProperty ("link_rel", tmp);
                    rv = anchor->GetRev (tmp);
                    if (NS_SUCCEEDED(rv))
                        SetStringProperty ("link_rev", tmp);
                    rv = element->GetTitle (tmp);
                                if (NS_SUCCEEDED(rv))
                        SetStringProperty ("link_title", tmp);
                    rv = anchor->GetType (tmp);
                    if (NS_SUCCEEDED(rv))
                        SetStringProperty ("link_type", tmp);

                    nsCString linkType;
                    NS_UTF16ToCString (tmp, NS_CSTRING_ENCODING_UTF8, linkType);

                    if (g_ascii_strcasecmp (linkType.get(), "text/smartbookmark") == 0)
                    {
                        SetIntProperty ("link_is_smart", TRUE);
                        
                        nsCOMPtr<nsIDOMNode> childNode;
                        node->GetFirstChild (getter_AddRefs(childNode));
                        if (childNode)
                        {
                            nsCOMPtr <nsIDOMHTMLImageElement> image = 
                                do_QueryInterface(childNode, &rv);

                            if (image)
                            {
                                nsString img;
                                rv = image->GetSrc (img);
                                if (!NS_FAILED(rv))
                                {
                                    SetStringProperty ("image", img);
                                }
                            }
                        }
                    }
                    else
                    {
                        SetIntProperty ("link_is_smart", FALSE);
                    }
                }
            
            }
            else if (g_ascii_strcasecmp (tag.get(), "option") == 0)
            {
                info->context = EPHY_EMBED_CONTEXT_NONE;
                return NS_OK;
            }
            else if (g_ascii_strcasecmp (tag.get(), "area") == 0)
            {
                info->context |= EPHY_EMBED_CONTEXT_LINK;
                nsCOMPtr <nsIDOMHTMLAreaElement> area =
                        do_QueryInterface(node, &rv);
                if (NS_SUCCEEDED(rv) && area)
                {
                    nsString href;
                    rv = area->GetHref (href);
                    if (NS_FAILED(rv))
                        return NS_ERROR_FAILURE;
                    
                    SetURIProperty (node, "link", href);
                    CheckLinkScheme (href);
                }
            }
            else if (g_ascii_strcasecmp (tag.get(), "input") == 0)
            {
                CheckInput (node);
            }
            else if (g_ascii_strcasecmp (tag.get(), "textarea") == 0)
            {
                info->context |= EPHY_EMBED_CONTEXT_INPUT;
            }

            if (!has_image)
            {
                nsString cssurl;
                rv = GetCSSBackground (node, cssurl);
                if (NS_SUCCEEDED (rv))
                {
                    nsCString bgimg;

                                        rv = ResolveBaseURL (cssurl, bgimg);
                                        if (NS_FAILED (rv))
                                                return NS_ERROR_FAILURE;
                    SetStringProperty ("image", bgimg.get());
                    info->context |= EPHY_EMBED_CONTEXT_IMAGE;
                    has_image = PR_TRUE;
                }
            }
        }
        
        nsCOMPtr<nsIDOMNode> parentNode;
        node->GetParentNode (getter_AddRefs(parentNode));
        node = parentNode;
    }
    
    return NS_OK;
}

nsresult EventContext::GetCSSBackground (nsIDOMNode *node, nsAString& url)
{
    if (!mViewCSS) return NS_ERROR_NOT_INITIALIZED;

    nsresult rv;

    const PRUnichar bgimage[] = {'b', 'a', 'c', 'k', 'g', 'r', 'o', 'u', 'n', 'd',
                     '-', 'i', 'm', 'a', 'g', 'e', '\0'};

    nsCOMPtr<nsIDOMElement> element = do_QueryInterface (node);
    NS_ENSURE_TRUE (element, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOMCSSStyleDeclaration> decl;
    mViewCSS->GetComputedStyle (element, nsString(),
                    getter_AddRefs (decl));
    NS_ENSURE_TRUE (decl, NS_ERROR_FAILURE);

    nsCOMPtr<nsIDOMCSSValue> CSSValue;
    decl->GetPropertyCSSValue (nsString(bgimage),
                   getter_AddRefs (CSSValue));

    nsCOMPtr<nsIDOMCSSPrimitiveValue> primitiveValue = 
        do_QueryInterface (CSSValue);
    if (!primitiveValue) return NS_ERROR_FAILURE;
    
    PRUint16 type;
    rv = primitiveValue->GetPrimitiveType (&type);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    if (type != nsIDOMCSSPrimitiveValue::CSS_URI) return NS_ERROR_FAILURE;

    rv = primitiveValue->GetStringValue (url);
    NS_ENSURE_SUCCESS (rv, NS_ERROR_FAILURE);

    return NS_OK;
}

nsresult EventContext::GetTargetCoords (nsIDOMEventTarget *aTarget, PRInt32 *aX, PRInt32 *aY)
{
    /* Calculate the node coordinates relative to the widget origin */
    nsCOMPtr<nsIDOMNSHTMLElement> elem (do_QueryInterface(aTarget));

    PRInt32 x = 0, y = 0;
    while (elem)
    {
        PRInt32 val;
        elem->GetOffsetTop(&val);   y += val;
        elem->GetScrollTop(&val);   y -= val;
        elem->GetOffsetLeft(&val);  x += val;
        elem->GetScrollLeft(&val);  x -= val;

        nsCOMPtr<nsIDOMElement> parent;
        elem->GetOffsetParent (getter_AddRefs (parent));
        elem = do_QueryInterface(parent);
    }

    *aX = x;
    *aY = y;

    return NS_OK;
}

nsresult EventContext::GetMouseEventInfo (nsIDOMMouseEvent *aMouseEvent, MozillaEmbedEvent *info)
{
    /* FIXME: casting 32-bit guint* to PRUint16* below will break on big-endian */
    PRUint16 btn = 1729;
    aMouseEvent->GetButton (&btn);

    switch (btn)
    {
        /* mozilla's button counting is one-off from gtk+'s */
        case 0:
            info->button = 1;
            break;
        case 1:
            info->button = 2;
            break;
        case 2:
            info->button = 3;
            break;

        case (PRUint16) -1:
            /* when the user submits a form with Return, mozilla synthesises
             * a _mouse_ click event with btn=65535 (-1).
             */
        default:
            info->button = 0;
            break;
    }

    if (info->button != 0)
    {
        /* OTOH, casting only between (un)signedness is safe */
        aMouseEvent->GetScreenX ((PRInt32*)&info->x);
        aMouseEvent->GetScreenY ((PRInt32*)&info->y);
    }
    else /* this is really a keyboard event */
    {
        nsCOMPtr<nsIDOMEventTarget> eventTarget;
        aMouseEvent->GetTarget (getter_AddRefs (eventTarget));

        GetTargetCoords (eventTarget, (PRInt32*)&info->x, (PRInt32*)&info->y);
    }

    /* be sure we are not clicking on the scroolbars */

    nsCOMPtr<nsIDOMNSEvent> nsEvent = do_QueryInterface(aMouseEvent);
    if (!nsEvent) return NS_ERROR_FAILURE;

#ifdef MOZ_NSIDOMNSEVENT_GETISTRUSTED
    /* make sure the event is trusted */
    PRBool isTrusted = PR_FALSE;
    nsEvent->GetIsTrusted (&isTrusted);
    if (!isTrusted) return NS_ERROR_UNEXPECTED;
#endif /* MOZ_NSIDOMNSEVENT_GETISTRUSTED */

    nsresult rv;
    nsCOMPtr<nsIDOMEventTarget> OriginalTarget;
    rv = nsEvent->GetOriginalTarget(getter_AddRefs(OriginalTarget));
    if (NS_FAILED (rv) || !OriginalTarget) return NS_ERROR_FAILURE;

    nsCOMPtr<nsIDOMNode> OriginalNode = do_QueryInterface(OriginalTarget);
    if (!OriginalNode) return NS_ERROR_FAILURE;

    nsString nodename;
    OriginalNode->GetNodeName(nodename);
    nsCString cNodeName;
    NS_UTF16ToCString (nodename, NS_CSTRING_ENCODING_UTF8, cNodeName);

    if (g_ascii_strcasecmp (cNodeName.get(), "xul:scrollbarbutton") == 0 ||
        g_ascii_strcasecmp (cNodeName.get(), "xul:thumb") == 0 ||
        g_ascii_strcasecmp (cNodeName.get(), "xul:vbox") == 0 ||
        g_ascii_strcasecmp (cNodeName.get(), "xul:spacer") == 0 ||
        g_ascii_strcasecmp (cNodeName.get(), "xul:slider") == 0)
        return NS_ERROR_FAILURE;

    nsCOMPtr<nsIDOMEventTarget> EventTarget;
    rv = aMouseEvent->GetTarget(getter_AddRefs(EventTarget));
    if (NS_FAILED (rv) || !EventTarget) return NS_ERROR_FAILURE;

    rv = GetEventContext (EventTarget, info);
    if (NS_FAILED (rv)) return rv;

    /* Get the modifier */

    PRBool mod_key;

    info->modifier = 0;

    aMouseEvent->GetAltKey(&mod_key);
    if (mod_key) info->modifier |= GDK_MOD1_MASK;

    aMouseEvent->GetShiftKey(&mod_key);
    if (mod_key) info->modifier |= GDK_SHIFT_MASK;

    /* no need to check GetMetaKey, it's always PR_FALSE,
     * see widget/src/gtk2/nsWindow.cpp:InitMouseEvent
     */
    
    aMouseEvent->GetCtrlKey(&mod_key);
    if (mod_key) info->modifier |= GDK_CONTROL_MASK;

    return NS_OK;
}

nsresult EventContext::GetKeyEventInfo (nsIDOMKeyEvent *aKeyEvent, MozillaEmbedEvent *info)
{
#ifdef MOZ_NSIDOMNSEVENT_GETISTRUSTED
    /* make sure the event is trusted */
    nsCOMPtr<nsIDOMNSEvent> nsEvent (do_QueryInterface (aKeyEvent));
    NS_ENSURE_TRUE (nsEvent, NS_ERROR_FAILURE);

    PRBool isTrusted = PR_FALSE;
    nsEvent->GetIsTrusted (&isTrusted);
    if (!isTrusted) return NS_ERROR_UNEXPECTED;
#endif /* MOZ_NSIDOMNSEVENT_GETISTRUSTED */


    info->button = 0;

    nsresult rv;
    PRUint32 keyCode;
    rv = aKeyEvent->GetKeyCode(&keyCode);
    if (NS_FAILED(rv)) return rv;
    info->keycode = keyCode;

    nsCOMPtr<nsIDOMEventTarget> target;
    rv = aKeyEvent->GetTarget(getter_AddRefs(target));
    if (NS_FAILED(rv) || !target) return NS_ERROR_FAILURE;

    GetTargetCoords (target, (PRInt32*)&info->x, (PRInt32*)&info->y);

    /* Context */
    rv = GetEventContext (target, info);
    if (NS_FAILED(rv)) return rv;

    /* Get the modifier */

    PRBool mod_key;

    info->modifier = 0;

    aKeyEvent->GetAltKey(&mod_key);
    if (mod_key) info->modifier |= GDK_MOD1_MASK;

    aKeyEvent->GetShiftKey(&mod_key);
    if (mod_key) info->modifier |= GDK_SHIFT_MASK;

    aKeyEvent->GetMetaKey(&mod_key);
    if (mod_key) info->modifier |= GDK_MOD2_MASK;
    
    aKeyEvent->GetCtrlKey(&mod_key);
    if (mod_key) info->modifier |= GDK_CONTROL_MASK;

    return NS_OK;
}

nsresult EventContext::IsPageFramed (nsIDOMNode *node, PRBool *Framed)
{
    nsresult rv;

    nsCOMPtr<nsIDOMDocument> mainDocument;
    rv = mBrowser->GetDocument (getter_AddRefs(mainDocument));
    if (NS_FAILED (rv) || !mainDocument) return NS_ERROR_FAILURE;
    
    nsCOMPtr<nsIDOMDocument> nodeDocument;
    rv = node->GetOwnerDocument (getter_AddRefs(nodeDocument));
    if (NS_FAILED (rv) || !nodeDocument) return NS_ERROR_FAILURE;
 
    *Framed = (mainDocument != nodeDocument);

        return NS_OK;
}

nsresult EventContext::GetTargetDocument (nsIDOMDocument **domDoc)
{
    if (!mDOMDocument) return NS_ERROR_FAILURE;

    *domDoc = mDOMDocument.get();

    NS_IF_ADDREF(*domDoc);

    return NS_OK;
}

nsresult EventContext::CheckInput (nsIDOMNode *aNode)
{
    const PRUnichar typeLiteral[] = { 't', 'y', 'p', 'e', '\0' };

    nsCOMPtr<nsIDOMElement> element;
    element = do_QueryInterface (aNode);
    if (!element) return NS_ERROR_FAILURE;

    nsString uValue;
    element->GetAttribute (nsString(typeLiteral), uValue);

    nsCString value;
    NS_UTF16ToCString (uValue, NS_CSTRING_ENCODING_UTF8, value);

    if (g_ascii_strcasecmp (value.get(), "image") == 0)
    {
        mEmbedEvent->context |= EPHY_EMBED_CONTEXT_IMAGE;
        nsCOMPtr<nsIDOMHTMLInputElement> input;
        input = do_QueryInterface (aNode);
        if (!input) return NS_ERROR_FAILURE;

        nsresult rv;
        nsString img;
        rv = input->GetSrc (img);
        if (NS_FAILED(rv)) return NS_ERROR_FAILURE;

        nsCString cImg;
        rv = ResolveBaseURL (img, cImg);
        if (NS_FAILED(rv)) return NS_ERROR_FAILURE;
        SetStringProperty ("image", cImg.get());
    }
    else if (g_ascii_strcasecmp (value.get(), "radio") != 0 &&
         g_ascii_strcasecmp (value.get(), "submit") != 0 &&
         g_ascii_strcasecmp (value.get(), "reset") != 0 &&
         g_ascii_strcasecmp (value.get(), "hidden") != 0 &&
         g_ascii_strcasecmp (value.get(), "button") != 0 &&
         g_ascii_strcasecmp (value.get(), "checkbox") != 0)
    {
        mEmbedEvent->context |= EPHY_EMBED_CONTEXT_INPUT;

        if (g_ascii_strcasecmp (value.get(), "password") == 0)
        {
            mEmbedEvent->context |= EPHY_EMBED_CONTEXT_INPUT_PASSWORD;
        }
    }

    return NS_OK;
}

nsresult EventContext::CheckLinkScheme (const nsAString &link)
{
    nsCOMPtr<nsIURI> uri;
    EphyUtils::NewURI (getter_AddRefs (uri), link);
    if (!uri) return NS_ERROR_FAILURE;

    nsresult rv;
    nsCString scheme;
    rv = uri->GetScheme (scheme);
    if (NS_FAILED (rv)) return NS_ERROR_FAILURE;

    if (g_ascii_strcasecmp (scheme.get(), "http") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "https") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "ftp") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "file") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "smb") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "sftp") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "ssh") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "data") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "resource") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "about") == 0 ||
        g_ascii_strcasecmp (scheme.get(), "gopher") == 0)
    {
        SetIntProperty ("link-has-web-scheme", TRUE);
    }

    return NS_OK;
}

nsresult EventContext::SetIntProperty (const char *name, int value)
{

    GValue *val = g_new0 (GValue, 1);

    g_value_init (val, G_TYPE_INT);
    
    g_value_set_int (val, value);

    mozilla_embed_event_set_property (mEmbedEvent, name, val);

    return NS_OK;
}

nsresult EventContext::SetStringProperty (const char *name, const char *value)
{
    GValue *val = g_new0 (GValue, 1);

    g_value_init (val, G_TYPE_STRING);
    
    g_value_set_string (val, value);
             
    mozilla_embed_event_set_property (mEmbedEvent, name, val);

    return NS_OK;
}

nsresult EventContext::SetStringProperty (const char *name, const nsAString &value)
{
    nsCString cValue;
    NS_UTF16ToCString (value, NS_CSTRING_ENCODING_UTF8, cValue);
    return SetStringProperty (name, cValue.get());
}

nsresult EventContext::SetURIProperty (nsIDOMNode *node, const char *name, const nsACString &value)
{
    nsresult rv;
    nsCOMPtr<nsIURI> uri;
    rv = EphyUtils::NewURI (getter_AddRefs (uri), value, mCharset.Length () ? mCharset.get() : nsnull, mBaseURI);
    if (NS_SUCCEEDED (rv) && uri)
    {
        /* Hide password part */
        nsCString user;
        uri->GetUsername (user);
        uri->SetUserPass (user);

        nsCString spec;
        uri->GetSpec (spec);
        rv = SetStringProperty (name, spec.get());
    }
    else
    {
        rv = SetStringProperty (name, nsCString(value).get());
    }

    return rv;
}

nsresult EventContext::SetURIProperty (nsIDOMNode *node, const char *name, const nsAString &value)
{
    nsCString cValue;
    NS_UTF16ToCString (value, NS_CSTRING_ENCODING_UTF8, cValue);
    return SetURIProperty (node, name, cValue);
}

/* static */
PRBool
EventContext::CheckKeyPress (nsIDOMKeyEvent *aEvent)
{
    PRBool retval = PR_FALSE;

    /* make sure the event is trusted */
    nsCOMPtr<nsIDOMNSEvent> nsEvent (do_QueryInterface (aEvent));
    NS_ENSURE_TRUE (nsEvent, retval);
    PRBool isTrusted = PR_FALSE;
    nsEvent->GetIsTrusted (&isTrusted);
    if (!isTrusted) return retval;

    /* check for alt/ctrl */
    PRBool isCtrl = PR_FALSE, isAlt = PR_FALSE;
    aEvent->GetCtrlKey (&isCtrl);
    aEvent->GetAltKey (&isAlt);
    if (isCtrl || isAlt) return retval;

    nsCOMPtr<nsIDOMNSUIEvent> uiEvent (do_QueryInterface (aEvent));
    NS_ENSURE_TRUE (uiEvent, retval);

    /* check for already handled event */
    PRBool isPrevented = PR_FALSE;
    uiEvent->GetPreventDefault (&isPrevented);
    if (isPrevented) return retval;

    /* check for form controls */
    nsresult rv;
    nsCOMPtr<nsIDOMEventTarget> target;
    rv = aEvent->GetTarget (getter_AddRefs (target));
    NS_ENSURE_SUCCESS (rv, retval);

    nsCOMPtr<nsIDOMHTMLInputElement> inputElement (do_QueryInterface (target));
    if (inputElement)
    {
        nsString type;
        inputElement->GetType (type);

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

        if (g_ascii_strcasecmp (cType.get(), "text") == 0 ||
            g_ascii_strcasecmp (cType.get(), "password") == 0 ||
            g_ascii_strcasecmp (cType.get(), "file") == 0) return retval;
    }

    nsCOMPtr<nsIDOMHTMLTextAreaElement> textArea;
    nsCOMPtr<nsIDOMHTMLSelectElement> selectElement;
    nsCOMPtr<nsIDOMHTMLIsIndexElement> indexElement;
    nsCOMPtr<nsIDOMHTMLObjectElement> objectElement;
    nsCOMPtr<nsIDOMHTMLEmbedElement> embedElement;

    if ((textArea = do_QueryInterface (target)) ||
        (selectElement = do_QueryInterface (target)) ||
        (indexElement = do_QueryInterface (target)) ||
        (objectElement = do_QueryInterface (target)) ||
        (embedElement = do_QueryInterface (target))) return retval;

    /* check for design mode */
    nsCOMPtr<nsIDOMNode> node (do_QueryInterface (target, &rv));
    NS_ENSURE_SUCCESS (rv, PR_FALSE);

    nsCOMPtr<nsIDOMDocument> doc;
    rv = node->GetOwnerDocument (getter_AddRefs (doc));
    NS_ENSURE_SUCCESS (rv, retval);

    nsCOMPtr<nsIDOMXULDocument> xul_document (do_QueryInterface(doc, &rv));
    if (xul_document) return retval;

    nsCOMPtr<nsIDOMNSHTMLDocument> htmlDoc (do_QueryInterface (doc));
    if (htmlDoc)
    {
        nsString uDesign;
        rv = htmlDoc->GetDesignMode (uDesign);
        NS_ENSURE_SUCCESS (rv, retval);

        nsCString design;
        NS_UTF16ToCString (uDesign, NS_CSTRING_ENCODING_UTF8, design);

        retval = g_ascii_strcasecmp (design.get(), "on") != 0;
    }
    else
    {
        retval = PR_TRUE;
    }

    return retval;
}