/* 
 * Copyright 2005, Ingo Weinhold, bonefish@users.sf.net. All rights reserved.
 * Distributed under the terms of the MIT License.
 */

#ifndef MESSAGING_SERVICE_H
#define MESSAGING_SERVICE_H

#include <Locker.h>
#include <MessagingServiceDefs.h>

// MessagingCommandHandler
class MessagingCommandHandler {
public:
        MessagingCommandHandler();
        virtual ~MessagingCommandHandler();

        virtual void HandleMessagingCommand(uint32 command, const void *data,
                int32 dataSize) = 0;
};

// MessagingArea
class MessagingArea {
public:
        ~MessagingArea();

        static status_t Create(area_id kernelAreaID, sem_id lockSem,
                sem_id counterSem, MessagingArea *&area);

        bool Lock();
        void Unlock();

        area_id ID() const;
        int32 Size() const;

        int32 CountCommands() const;
        const messaging_command *PopCommand();

        void Discard();

        area_id NextKernelAreaID() const;
        void SetNextArea(MessagingArea *area);
        MessagingArea *NextArea() const;

private:
        MessagingArea();

        messaging_area_header   *fHeader;
        area_id                                 fID;
        int32                                   fSize;
        sem_id                                  fLockSem;
        sem_id                                  fCounterSem;    // TODO: Remove, if not needed.
        MessagingArea                   *fNextArea;
};

// MessagingService
class MessagingService {
private:
        MessagingService();
        ~MessagingService();

        status_t Init();

public:
        static status_t CreateDefault();
        static void DeleteDefault();
        static MessagingService *Default();

        void SetCommandHandler(uint32 command, MessagingCommandHandler *handler);

private:
        MessagingCommandHandler *_GetCommandHandler(uint32 command) const;

        static int32 _CommandProcessorEntry(void *data);
        int32 _CommandProcessor();

        class DefaultSendCommandHandler;
        struct CommandHandlerMap;

        static MessagingService *sService;

        mutable BLocker                 fLock;
        sem_id                                  fLockSem;
        sem_id                                  fCounterSem;
        MessagingArea                   *fFirstArea;
        CommandHandlerMap               *fCommandHandlers;
        thread_id                               fCommandProcessor;
        volatile bool                   fTerminating;
};

#endif  // MESSAGING_SERVICE_H