/*

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

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

 * Copyright (C) 2003, 2008, 2010 Apple Inc. All rights reserved.

 *

 * 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.

 *

 */

#ifndef HTMLLinkElement_h

#define HTMLLinkElement_h

#include "CSSStyleSheet.h"

#include "CachedResourceClient.h"

#include "CachedResourceHandle.h"

#include "HTMLElement.h"

namespace WebCore {

class CachedCSSStyleSheet;

class KURL;

class HTMLLinkElement : public HTMLElement, public CachedResourceClient {

public:

    struct RelAttribute {

        bool m_isStyleSheet;

        bool m_isIcon;

        bool m_isAlternate;

        bool m_isDNSPrefetch;

#if ENABLE(LINK_PREFETCH)

        bool m_isLinkPrefetch;

#endif

        RelAttribute()

            : m_isStyleSheet(false)

            , m_isIcon(false)

            , m_isAlternate(false)

            , m_isDNSPrefetch(false)

#if ENABLE(LINK_PREFETCH)

            , m_isLinkPrefetch(false)

#endif

            { 

            }

    };

    static PassRefPtr<HTMLLinkElement> create(const QualifiedName&, Document*, bool createdByParser);

    virtual ~HTMLLinkElement();

    KURL href() const;

    String rel() const;

    virtual String target() const;

    String type() const;

    StyleSheet* sheet() const;

    bool isLoading() const;

    bool isDisabled() const { return m_disabledState == Disabled; }

    bool isEnabledViaScript() const { return m_disabledState == EnabledViaScript; }

    bool isIcon() const { return m_relAttribute.m_isIcon; }

    virtual void attach();

    virtual bool canLazyAttach() { return false; }

private:

    virtual HTMLTagStatus endTagRequirement() const { return TagStatusForbidden; }

    virtual int tagPriority() const { return 0; }

    virtual void parseMappedAttribute(Attribute*);

    void process();

    static void processCallback(Node*);

    virtual void insertedIntoDocument();

    virtual void removedFromDocument();

    // from CachedResourceClient

    virtual void setCSSStyleSheet(const String& href, const KURL& baseURL, const String& charset, const CachedCSSStyleSheet* sheet);

    virtual bool sheetLoaded();

    bool isAlternate() const { return m_disabledState == Unset && m_relAttribute.m_isAlternate; }

    void setDisabledState(bool _disabled);

    virtual bool isURLAttribute(Attribute*) const;

public:

    static void tokenizeRelAttribute(const AtomicString& value, RelAttribute&);

private:

    virtual void addSubresourceAttributeURLs(ListHashSet<KURL>&) const;

    virtual void finishParsingChildren();

private:

    HTMLLinkElement(const QualifiedName&, Document*, bool createdByParser);

    enum DisabledState {

        Unset,

        EnabledViaScript,

        Disabled

    };

    CachedResourceHandle<CachedCSSStyleSheet> m_cachedSheet;

    RefPtr<CSSStyleSheet> m_sheet;

    KURL m_url;

    String m_type;

    String m_media;

    DisabledState m_disabledState;

    RelAttribute m_relAttribute;

    bool m_loading;

    bool m_createdByParser;

    bool m_shouldProcessAfterAttach;

};

} //namespace

#endif