
/*
 * $Id$
 *
 * AUTHOR: Duane Wessels
 *
 * SQUID Web Proxy Cache          http://www.squid-cache.org/
 * ----------------------------------------------------------
 *
 *  Squid is the result of efforts by numerous individuals from
 *  the Internet community; see the CONTRIBUTORS file for full
 *  details.   Many organizations have provided support for Squid's
 *  development; see the SPONSORS file for full details.  Squid is
 *  Copyrighted (C) 2001 by the Regents of the University of
 *  California; see the COPYRIGHT file for full details.  Squid
 *  incorporates software developed and/or copyrighted by other
 *  sources; see the CREDITS file for full details.
 *
 *  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 of the License, 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, USA.
 *
 */
#ifndef SQUID_SERVER_H
#define SQUID_SERVER_H

#include "StoreIOBuffer.h"
#include "forward.h"
#include "BodyPipe.h"
#include "base/AsyncJob.h"
#include "CommCalls.h"

#if USE_ADAPTATION
#include "adaptation/forward.h"
#include "adaptation/Initiator.h"
#endif

/**
 * ServerStateData is a common base for server-side classes such as
 * HttpStateData and FtpStateData. All such classes must be able to
 * consume request bodies from the client-side or ICAP producer, adapt
 * virgin responses using ICAP, and provide the client-side consumer with
 * responses.
 *
 \todo TODO: Rename to ServerStateDataInfoRecordHandler.
 */
class ServerStateData:
#if USE_ADAPTATION
        public Adaptation::Initiator,
        public BodyProducer,
#endif
        public BodyConsumer
{

public:
    ServerStateData(FwdState *);
    virtual ~ServerStateData();

    /// \return primary or "request data connection" fd
    virtual int dataDescriptor() const = 0;

    // BodyConsumer: consume request body or adapted response body.
    // The implementation just calls the corresponding HTTP or ICAP handle*()
    // method, depending on the pipe.
    virtual void noteMoreBodyDataAvailable(BodyPipe::Pointer);
    virtual void noteBodyProductionEnded(BodyPipe::Pointer);
    virtual void noteBodyProducerAborted(BodyPipe::Pointer);

    /// read response data from the network
    virtual void maybeReadVirginBody() = 0;

    /// abnormal transaction termination; reason is for debugging only
    virtual void abortTransaction(const char *reason) = 0;

    /// a hack to reach HttpStateData::orignal_request
    virtual  HttpRequest *originalRequest();

#if USE_ADAPTATION
    void adaptationAclCheckDone(Adaptation::ServiceGroupPointer group);
    static void adaptationAclCheckDoneWrapper(Adaptation::ServiceGroupPointer group, void *data);

    // ICAPInitiator: start an ICAP transaction and receive adapted headers.
    virtual void noteAdaptationAnswer(HttpMsg *message);
    virtual void noteAdaptationQueryAbort(bool final);

    // BodyProducer: provide virgin response body to ICAP.
    virtual void noteMoreBodySpaceAvailable(BodyPipe::Pointer );
    virtual void noteBodyConsumerAborted(BodyPipe::Pointer );
#endif
    virtual void processReplyBody() = 0;

//AsyncJob virtual methods
    virtual void swanSong();
    virtual bool doneAll() const {
        return
#if USE_ADAPTATION
            Adaptation::Initiator::doneAll() &&
            BodyProducer::doneAll() &&
#endif
            BodyConsumer::doneAll() && false;
    }

public: // should be protected
    void serverComplete();     /**< call when no server communication is expected */

private:
    void serverComplete2();    /**< Continuation of serverComplete */
    bool completed;            /**< serverComplete() has been called */

protected:
    // kids customize these
    virtual void haveParsedReplyHeaders(); /**< called when got final headers */
    virtual void completeForwarding(); /**< default calls fwd->complete() */

    // BodyConsumer for HTTP: consume request body.
    bool startRequestBodyFlow();
    void handleMoreRequestBodyAvailable();
    void handleRequestBodyProductionEnded();
    virtual void handleRequestBodyProducerAborted() = 0;

    /// whether it is not too late to write to the server
    bool canSend(int fd) const;
    // sending of the request body to the server
    void sendMoreRequestBody();
    // has body; kids overwrite to increment I/O stats counters
    virtual void sentRequestBody(const CommIoCbParams &io) = 0;
    virtual void doneSendingRequestBody() = 0;

    virtual void closeServer() = 0;            /**< end communication with the server */
    virtual bool doneWithServer() const = 0;   /**< did we end communication? */

    /// Entry-dependent callbacks use this check to quit if the entry went bad
    bool abortOnBadEntry(const char *abortReason);

#if USE_ADAPTATION
    void startAdaptation(const Adaptation::ServiceGroupPointer &group, HttpRequest *cause);
    void adaptVirginReplyBody(const char *buf, ssize_t len);
    void cleanAdaptation();
    virtual bool doneWithAdaptation() const;   /**< did we end ICAP communication? */

    // BodyConsumer for ICAP: consume adapted response body.
    void handleMoreAdaptedBodyAvailable();
    void handleAdaptedBodyProductionEnded();
    void handleAdaptedBodyProducerAborted();

    void handleAdaptationCompleted();
    void handleAdaptationAborted(bool bypassable = false);
#endif

protected:
    const HttpReply *virginReply() const;
    HttpReply *virginReply();
    HttpReply *setVirginReply(HttpReply *r);

    HttpReply *finalReply();
    HttpReply *setFinalReply(HttpReply *r);

    // Kids use these to stuff data into the response instead of messing with the entry directly
    void adaptOrFinalizeReply();
    void addVirginReplyBody(const char *buf, ssize_t len);
    void storeReplyBody(const char *buf, ssize_t len);
    size_t replyBodySpace(const MemBuf &readBuf, const size_t minSpace) const;

    // These should be private
    int64_t currentOffset;	/**< Our current offset in the StoreEntry */
    MemBuf *responseBodyBuffer;	/**< Data temporarily buffered for ICAP */

public: // should not be
    StoreEntry *entry;
    FwdState::Pointer fwd;
    HttpRequest *request;

protected:
    BodyPipe::Pointer requestBodySource;  /**< to consume request body */
    AsyncCall::Pointer requestSender;     /**< set if we are expecting comm_write to call us back */

#if USE_ADAPTATION
    BodyPipe::Pointer virginBodyDestination;  /**< to provide virgin response body */
    Adaptation::Initiate *adaptedHeadSource;  /**< to get adapted response headers */
    BodyPipe::Pointer adaptedBodySource;      /**< to consume adated response body */

    bool adaptationAccessCheckPending;
    bool startedAdaptation;
#endif

private:
    void quitIfAllDone();            /**< successful termination */
    void sendBodyIsTooLargeError();
    void maybePurgeOthers();

    HttpReply *theVirginReply;       /**< reply received from the origin server */
    HttpReply *theFinalReply;        /**< adapted reply from ICAP or virgin reply */
};

#endif /* SQUID_SERVER_H */
