/*

    Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)

    Copyright (C) 2001 Dirk Mueller <mueller@kde.org>

    Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.

    Copyright (C) 2009 Torch Mobile Inc. http://www.torchmobile.com/

    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.

    This class provides all functionality needed for loading images, style sheets and html

    pages from the web. It has a memory cache for these objects.

*/

#ifndef DocLoader_h

#define DocLoader_h

#include "CachedResource.h"

#include "CachedResourceHandle.h"

#include "CachePolicy.h"

#include "StringHash.h"

#include <wtf/HashMap.h>

#include <wtf/HashSet.h>

#include <wtf/ListHashSet.h>

namespace WebCore {

class CachedCSSStyleSheet;

class CachedFont;

class CachedImage;

class CachedScript;

class CachedXSLStyleSheet;

class Document;

class Frame;

class ImageLoader;

class KURL;

// The DocLoader manages the loading of scripts/images/stylesheets for a single document.

class DocLoader : public Noncopyable {

friend class Cache;

friend class ImageLoader;

public:

    DocLoader(Document*);

    ~DocLoader();

    CachedImage* requestImage(const String& url);

    CachedCSSStyleSheet* requestCSSStyleSheet(const String& url, const String& charset);

    CachedCSSStyleSheet* requestUserCSSStyleSheet(const String& url, const String& charset);

    CachedScript* requestScript(const String& url, const String& charset);

    CachedFont* requestFont(const String& url);

#if ENABLE(XSLT)

    CachedXSLStyleSheet* requestXSLStyleSheet(const String& url);

#endif

#if ENABLE(XBL)

    CachedXBLDocument* requestXBLDocument(const String &url);

#endif

#if ENABLE(LINK_PREFETCH)

    CachedResource* requestLinkPrefetch(const String &url);

#endif

    // Logs an access denied message to the console for the specified URL.

    void printAccessDeniedMessage(const KURL& url) const;

    CachedResource* cachedResource(const String& url) const { return m_documentResources.get(url).get(); }

    typedef HashMap<String, CachedResourceHandle<CachedResource> > DocumentResourceMap;

    const DocumentResourceMap& allCachedResources() const { return m_documentResources; }

    bool autoLoadImages() const { return m_autoLoadImages; }

    void setAutoLoadImages(bool);

    CachePolicy cachePolicy() const;

    Frame* frame() const; // Can be NULL

    Document* doc() const { return m_doc; }

    void removeCachedResource(CachedResource*) const;

    void setLoadInProgress(bool);

    bool loadInProgress() const { return m_loadInProgress; }

    void setAllowStaleResources(bool allowStaleResources) { m_allowStaleResources = allowStaleResources; }

    void incrementRequestCount(const CachedResource*);

    void decrementRequestCount(const CachedResource*);

    int requestCount();

    void clearPreloads();

    void clearPendingPreloads();

    void preload(CachedResource::Type, const String& url, const String& charset, bool referencedFromBody);

    void checkForPendingPreloads();

    void printPreloadStats();

private:

    CachedResource* requestResource(CachedResource::Type, const String& url, const String& charset, bool isPreload = false);

    void requestPreload(CachedResource::Type, const String& url, const String& charset);

    void checkForReload(const KURL&);

    void checkCacheObjectStatus(CachedResource*);

    bool canRequest(CachedResource::Type, const KURL&);

    Cache* m_cache;

    HashSet<String> m_reloadedURLs;

    mutable DocumentResourceMap m_documentResources;

    Document* m_doc;

    int m_requestCount;

    OwnPtr<ListHashSet<CachedResource*> > m_preloads;

    struct PendingPreload {

        CachedResource::Type m_type;

        String m_url;

        String m_charset;

    };

    Vector<PendingPreload> m_pendingPreloads;

    //29 bits left

    bool m_autoLoadImages : 1;

    bool m_loadInProgress : 1;

    bool m_allowStaleResources : 1;

};

}

#endif