/**

 * This file is part of the DOM implementation for KDE.

 *

 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)

 *           (C) 1999 Antti Koivisto (koivisto@kde.org)

 *           (C) 2001 Dirk Mueller (mueller@kde.org)

 * Copyright (C) 2003 Apple Computer, Inc.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public License

 * along with this library; see the file COPYING.LIB.  If not, write to

 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#include "config.h"

#include "HTMLLinkElement.h"

#include "CachedCSSStyleSheet.h"

#include "DocLoader.h"

#include "Document.h"

#include "Frame.h"

#include "FrameLoader.h"

#include "FrameTree.h"

#include "HTMLNames.h"

#include "MediaList.h"

#include "MediaQueryEvaluator.h"

namespace WebCore {

using namespace HTMLNames;

HTMLLinkElement::HTMLLinkElement(Document *doc)

    : HTMLElement(linkTag, doc)

    , m_cachedSheet(0)

    , m_disabledState(0)

    , m_loading(false)

    , m_alternate(false)

    , m_isStyleSheet(false)

    , m_isIcon(false)

{

}

HTMLLinkElement::~HTMLLinkElement()

{

    if (m_cachedSheet) {

        m_cachedSheet->deref(this);

        if (m_loading && !isDisabled() && !isAlternate())

            document()->removePendingSheet();

    }

}

void HTMLLinkElement::setDisabledState(bool _disabled)

{

    int oldDisabledState = m_disabledState;

    m_disabledState = _disabled ? 2 : 1;

    if (oldDisabledState != m_disabledState) {

        // If we change the disabled state while the sheet is still loading, then we have to

        // perform three checks:

        if (isLoading()) {

            // Check #1: If the sheet becomes disabled while it was loading, and if it was either

            // a main sheet or a sheet that was previously enabled via script, then we need

            // to remove it from the list of pending sheets.

            if (m_disabledState == 2 && (!m_alternate || oldDisabledState == 1))

                document()->removePendingSheet();

            // Check #2: An alternate sheet becomes enabled while it is still loading.

            if (m_alternate && m_disabledState == 1)

                document()->addPendingSheet();

            // Check #3: A main sheet becomes enabled while it was still loading and

            // after it was disabled via script.  It takes really terrible code to make this

            // happen (a double toggle for no reason essentially).  This happens on

            // virtualplastic.net, which manages to do about 12 enable/disables on only 3

            // sheets. :)

            if (!m_alternate && m_disabledState == 1 && oldDisabledState == 2)

                document()->addPendingSheet();

            // If the sheet is already loading just bail.

            return;

        }

        // Load the sheet, since it's never been loaded before.

        if (!m_sheet && m_disabledState == 1)

            process();

        else

            document()->updateStyleSelector(); // Update the style selector.

    }

}

StyleSheet* HTMLLinkElement::sheet() const

{

    return m_sheet.get();

}

void HTMLLinkElement::parseMappedAttribute(MappedAttribute *attr)

{

    if (attr->name() == relAttr) {

#if PRELOAD_SCANNER_ENABLED

        tokenizeRelAttribute(attr->value(), m_isStyleSheet, m_alternate, m_isIcon);

#else

        tokenizeRelAttribute(attr->value());

#endif

        process();

    } else if (attr->name() == hrefAttr) {

        m_url = document()->completeURL(parseURL(attr->value()));

        process();

    } else if (attr->name() == typeAttr) {

        m_type = attr->value();

        process();

    } else if (attr->name() == mediaAttr) {

        m_media = attr->value().domString().lower();

        process();

    } else if (attr->name() == disabledAttr) {

        setDisabledState(!attr->isNull());

    } else {

        if (attr->name() == titleAttr && m_sheet)

            m_sheet->setTitle(attr->value());

        HTMLElement::parseMappedAttribute(attr);

    }

}

#if PRELOAD_SCANNER_ENABLED

void HTMLLinkElement::tokenizeRelAttribute(const AtomicString& relStr, bool& styleSheet, bool& alternate, bool& icon)

{

    styleSheet = false;

    icon = false; 

    alternate = false;

    String rel = relStr.domString().lower();

    if (rel == "stylesheet")

        styleSheet = true;

    else if (rel == "icon" || rel == "shortcut icon")

        icon = true;

    else if (rel == "alternate stylesheet" || rel == "stylesheet alternate") {

        styleSheet = true;

        alternate = true;

    } else {

        // Tokenize the rel attribute and set bits based on specific keywords that we find.

        rel.replace('\n', ' ');

        Vector<String> list = rel.split(' ');

        Vector<String>::const_iterator end = list.end();

        for (Vector<String>::const_iterator it = list.begin(); it != end; ++it) {

            if (*it == "stylesheet")

                styleSheet = true;

            else if (*it == "alternate")

                alternate = true;

            else if (*it == "icon")

                icon = true;

#else

void HTMLLinkElement::tokenizeRelAttribute(const AtomicString& relStr)

{

    m_isStyleSheet = m_isIcon = m_alternate = false;

    String rel = relStr.domString().lower();

    if (rel == "stylesheet")

        m_isStyleSheet = true;

    else if (rel == "icon" || rel == "shortcut icon")

        m_isIcon = true;

    else if (rel == "alternate stylesheet" || rel == "stylesheet alternate")

        m_isStyleSheet = m_alternate = true;

    else {

        // Tokenize the rel attribute and set bits based on specific keywords that we find.

        rel.replace('\n', ' ');

        Vector<String> list = rel.split(' ');

        Vector<String>::const_iterator end = list.end();

        for (Vector<String>::const_iterator it = list.begin(); it != end; ++it) {

            if (*it == "stylesheet")

                m_isStyleSheet = true;

            else if (*it == "alternate")

                m_alternate = true;

            else if (*it == "icon")

                m_isIcon = true;

#endif

        }

    }

}

void HTMLLinkElement::process()

{

    if (!inDocument())

        return;

    String type = m_type.lower();

    // IE extension: location of small icon for locationbar / bookmarks

    // We'll record this URL per document, even if we later only use it in top level frames

    if (m_isIcon && !m_url.isEmpty())

        document()->setIconURL(m_url, type);

    // Stylesheet

    // This was buggy and would incorrectly match <link rel="alternate">, which has a different specified meaning. -dwh

    if (m_disabledState != 2 && (type.contains("text/css") || m_isStyleSheet) && document()->frame()) {

        // no need to load style sheets which aren't for the screen output

        // ### there may be in some situations e.g. for an editor or script to manipulate

        // also, don't load style sheets for standalone documents

        MediaQueryEvaluator allEval(true);

        MediaQueryEvaluator screenEval("screen", true);

        MediaQueryEvaluator printEval("print", true);

        RefPtr<MediaList> media = new MediaList((CSSStyleSheet*)0, m_media, true);

        if (allEval.eval(media.get()) || screenEval.eval(media.get()) || printEval.eval(media.get())) {

            // Add ourselves as a pending sheet, but only if we aren't an alternate 

            // stylesheet.  Alternate stylesheets don't hold up render tree construction.

            if (!isAlternate())

                document()->addPendingSheet();

            String chset = getAttribute(charsetAttr);

            if (chset.isEmpty() && document()->frame())

                chset = document()->frame()->loader()->encoding();

            if (m_cachedSheet) {

                if (m_loading)

                    document()->removePendingSheet();

                m_cachedSheet->deref(this);

            }

            m_loading = true;

            m_cachedSheet = document()->docLoader()->requestCSSStyleSheet(m_url, chset);

            if (m_cachedSheet)

                m_cachedSheet->ref(this);

            else if (!isAlternate()) { // request may have been denied if stylesheet is local and document is remote.

                m_loading = false;

                document()->removePendingSheet();

            }

        }

    } else if (m_sheet) {

        // we no longer contain a stylesheet, e.g. perhaps rel or type was changed

        m_sheet = 0;

        document()->updateStyleSelector();

    }

}

void HTMLLinkElement::insertedIntoDocument()

{

    HTMLElement::insertedIntoDocument();

    process();

}

void HTMLLinkElement::removedFromDocument()

{

    HTMLElement::removedFromDocument();

    process();

}

void HTMLLinkElement::setCSSStyleSheet(const String& url, const String& charset, const String& sheetStr)

{

    m_sheet = new CSSStyleSheet(this, url, charset);

    m_sheet->parseString(sheetStr, !document()->inCompatMode());

    m_sheet->setTitle(title());

    RefPtr<MediaList> media = new MediaList((CSSStyleSheet*)0, m_media, true);

    m_sheet->setMedia(media.get());

    m_loading = false;

    m_sheet->checkLoaded();

}

bool HTMLLinkElement::isLoading() const

{

    if (m_loading)

        return true;

    if (!m_sheet)

        return false;

    return static_cast<CSSStyleSheet *>(m_sheet.get())->isLoading();

}

bool HTMLLinkElement::sheetLoaded()

{

    if (!isLoading() && !isDisabled() && !isAlternate()) {

        document()->removePendingSheet();

        return true;

    }

    return false;

}

bool HTMLLinkElement::isURLAttribute(Attribute *attr) const

{

    return attr->name() == hrefAttr;

}

bool HTMLLinkElement::disabled() const

{

    return !getAttribute(disabledAttr).isNull();

}

void HTMLLinkElement::setDisabled(bool disabled)

{

    setAttribute(disabledAttr, disabled ? "" : 0);

}

String HTMLLinkElement::charset() const

{

    return getAttribute(charsetAttr);

}

void HTMLLinkElement::setCharset(const String& value)

{

    setAttribute(charsetAttr, value);

}

String HTMLLinkElement::href() const

{

    return document()->completeURL(getAttribute(hrefAttr));

}

void HTMLLinkElement::setHref(const String& value)

{

    setAttribute(hrefAttr, value);

}

String HTMLLinkElement::hreflang() const

{

    return getAttribute(hreflangAttr);

}

void HTMLLinkElement::setHreflang(const String& value)

{

    setAttribute(hreflangAttr, value);

}

String HTMLLinkElement::media() const

{

    return getAttribute(mediaAttr);

}

void HTMLLinkElement::setMedia(const String& value)

{

    setAttribute(mediaAttr, value);

}

String HTMLLinkElement::rel() const

{

    return getAttribute(relAttr);

}

void HTMLLinkElement::setRel(const String& value)

{

    setAttribute(relAttr, value);

}

String HTMLLinkElement::rev() const

{

    return getAttribute(revAttr);

}

void HTMLLinkElement::setRev(const String& value)

{

    setAttribute(revAttr, value);

}

String HTMLLinkElement::target() const

{

    return getAttribute(targetAttr);

}

void HTMLLinkElement::setTarget(const String& value)

{

    setAttribute(targetAttr, value);

}

String HTMLLinkElement::type() const

{

    return getAttribute(typeAttr);

}

void HTMLLinkElement::setType(const String& value)

{

    setAttribute(typeAttr, value);

}

}