// ======================================================================
// \title  FilePacket.hpp
// \author bocchino
// \brief  hpp file for FilePacket
//
// \copyright
// Copyright 2009-2016, by the California Institute of Technology.
// ALL RIGHTS RESERVED.  United States Government Sponsorship
// acknowledged.
//
// ======================================================================

#ifndef Fw_FilePacket_HPP
#define Fw_FilePacket_HPP

#include <CFDP/Checksum/Checksum.hpp>
#include <Fw/Buffer/Buffer.hpp>
#include <Fw/FPrimeBasicTypes.hpp>
#include <Fw/Types/SerialBuffer.hpp>
#include <Fw/Types/Serializable.hpp>

// Forward declaration for UTs
namespace Svc {
class FileUplinkTester;
class FileDownlinkTester;
}  // namespace Svc

namespace Fw {

//! \class FilePacket
//! \brief A file packet
//!
union FilePacket {
  public:
    // ----------------------------------------------------------------------
    // Types
    // ----------------------------------------------------------------------

    //! Packet type
    typedef enum { T_START = 0, T_DATA = 1, T_END = 2, T_CANCEL = 3, T_NONE = 255 } Type;

    //! The type of a path name
    class PathName {
        friend union FilePacket;
        friend class Svc::FileDownlinkTester;
        friend class Svc::FileUplinkTester;

      public:
        //! The maximum length of a path name
        enum { MAX_LENGTH = 255 };

      private:
        //! The length
        U8 m_length;

        //! Pointer to the path value
        const char* m_value;

      public:
        //! Initialize a PathName
        void initialize(const char* const value  //! The path value
        );

        //! Compute the buffer size needed to hold this PathName
        U32 bufferSize() const;

        //! Get the length of the path name value
        U32 getLength(void) const { return this->m_length; };

        //! Get the path name value
        const char* getValue(void) const { return this->m_value; };

      private:
        //! Initialize this PathName from a SerialBuffer
        SerializeStatus fromSerialBuffer(SerialBuffer& serialBuffer);

        //! Write this PathName to a SerialBuffer
        SerializeStatus toSerialBuffer(SerialBuffer& serialBuffer) const;
    };

    //! The type of a packet header
    class Header {
        friend union FilePacket;
        friend class FilePacketTester;
        friend class Svc::FileDownlinkTester;
        friend class Svc::FileUplinkTester;

      private:
        //! The packet type
        Type m_type;

        //! The sequence index
        U32 m_sequenceIndex;

      public:
        //! Header size
        enum { HEADERSIZE = sizeof(U8) + sizeof(U32) };

      private:
        //! Initialize a file packet header
        void initialize(const Type type,         //!< The packet type
                        const U32 sequenceIndex  //!< The sequence index
        );

        //! Compute the buffer size needed to hold this Header
        U32 bufferSize() const;

        //! Initialize this Header from a SerialBuffer
        SerializeStatus fromSerialBuffer(SerialBuffer& serialBuffer);

        //! Write this Header to a SerialBuffer
        SerializeStatus toSerialBuffer(SerialBuffer& serialBuffer) const;

      public:
        Type getType(void) const { return this->m_type; };

        U32 getSequenceIndex(void) const { return this->m_sequenceIndex; };
    };

    //! The type of a start packet
    struct StartPacket {
        friend union FilePacket;

      private:
        //! The packet header
        Header m_header;

        //! The file size
        U32 m_fileSize;

        //! The source path
        PathName m_sourcePath;

        //! The destination path
        PathName m_destinationPath;

      public:
        //! Initialize a StartPacket with sequence number 0
        void initialize(const U32 fileSize,                //!< The file size
                        const char* const sourcePath,      //!< The source path
                        const char* const destinationPath  //!< The destination path
        );

        //! Compute the buffer size needed to hold this StartPacket
        U32 bufferSize() const;

        //! Convert this StartPacket to a Buffer
        SerializeStatus toBuffer(Buffer& buffer) const;

        //! Get this as a Header
        const FilePacket::Header& asHeader() const { return this->m_header; };

        //! Get the destination path
        const PathName& getDestinationPath() const { return this->m_destinationPath; };

        //! Get the source path
        const PathName& getSourcePath() const { return this->m_sourcePath; };

        //! Get the file size
        U32 getFileSize() const { return this->m_fileSize; };

      private:
        //! Initialize this StartPacket from a SerialBuffer
        SerializeStatus fromSerialBuffer(SerialBuffer& serialBuffer);

        //! Write this StartPacket to a SerialBuffer
        SerializeStatus toSerialBuffer(SerialBuffer& serialBuffer) const;
    };

    //! The type of a data packet
    class DataPacket {
        friend union FilePacket;
        friend class Svc::FileDownlinkTester;
        friend class Svc::FileUplinkTester;

      private:
        //! The packet header
        Header m_header;

        //! The byte offset of the packet data into the destination file
        U32 m_byteOffset;

        //! The size of the file data in the packet
        U16 m_dataSize;

        //! Pointer to the file data
        const U8* m_data;

      public:
        //! header size
        enum { HEADERSIZE = Header::HEADERSIZE + sizeof(U32) + sizeof(U16) };

        //! Initialize a data packet
        void initialize(const U32 sequenceIndex,  //!< The sequence index
                        const U32 byteOffset,     //!< The byte offset
                        const U16 dataSize,       //!< The data size
                        const U8* const data      //!< The file data
        );

        //! Compute the buffer size needed to hold this DataPacket
        U32 bufferSize() const;

        //! Convert this DataPacket to a Buffer
        SerializeStatus toBuffer(Buffer& buffer) const;

        //! Get this as a Header
        const FilePacket::Header& asHeader() const { return this->m_header; };

        //! Get the byte offset
        U32 getByteOffset() const { return this->m_byteOffset; };

        //! Get the data size
        U32 getDataSize() const { return this->m_dataSize; };

        //! Get the data
        const U8* getData() const { return this->m_data; };

      private:
        //! Initialize this DataPacket from a SerialBuffer
        SerializeStatus fromSerialBuffer(SerialBuffer& serialBuffer);

        //! Compute the fixed-length data size of a StartPacket
        U32 fixedLengthSize() const;

        //! Write this DataPacket to a SerialBuffer
        SerializeStatus toSerialBuffer(SerialBuffer& serialBuffer) const;
    };

    //! The type of an end packet
    class EndPacket {
        friend union FilePacket;
        friend class Svc::FileDownlinkTester;
        friend class Svc::FileUplinkTester;

      private:
        //! The packet header
        Header m_header;

      public:
        //! Set the checksum
        void setChecksum(const CFDP::Checksum& checksum);

        //! Get the checksum
        void getChecksum(CFDP::Checksum& checksum) const;

        //! Compute the buffer size needed to hold this EndPacket
        U32 bufferSize() const;

        //! Convert this EndPacket to a Buffer
        SerializeStatus toBuffer(Buffer& buffer) const;

        //! Get this as a Header
        const FilePacket::Header& asHeader() const { return this->m_header; };

      public:
        //! Initialize an end packet
        void initialize(const U32 sequenceIndex,        //!< The sequence index
                        const CFDP::Checksum& checksum  //!< The checksum
        );

      private:
        //! The checksum
        U32 m_checksumValue;

        //! Initialize this EndPacket from a SerialBuffer
        SerializeStatus fromSerialBuffer(SerialBuffer& serialBuffer);

        //! Write this EndPacket to a SerialBuffer
        SerializeStatus toSerialBuffer(SerialBuffer& serialBuffer) const;
    };

    //! The type of a cancel packet
    class CancelPacket {
        friend union FilePacket;
        friend class Svc::FileDownlinkTester;
        friend class Svc::FileUplinkTester;

      private:
        //! The packet header
        Header m_header;

      public:
        //! Initialize a cancel packet
        void initialize(const U32 sequenceIndex  //!< The sequence index
        );

        //! Compute the buffer size needed to hold this CancelPacket
        U32 bufferSize() const;

        //! Convert this CancelPacket to a Buffer
        SerializeStatus toBuffer(Buffer& buffer) const;

        //! Get this as a Header
        const FilePacket::Header& asHeader() const { return this->m_header; };

      private:
        //! Initialize this CancelPacket from a SerialBuffer
        SerializeStatus fromSerialBuffer(SerialBuffer& serialBuffer);
    };

  public:
    // ----------------------------------------------------------------------
    // Constructor
    // ----------------------------------------------------------------------

    FilePacket() { this->m_header.m_type = T_NONE; }

  public:
    // ----------------------------------------------------------------------
    // Public instance methods
    // ----------------------------------------------------------------------

    //! Initialize this from a Buffer
    //!
    SerializeStatus fromBuffer(const Buffer& buffer);

    //! Get this as a Header
    //!
    const Header& asHeader() const;

    //! Get this as a StartPacket
    //!
    const StartPacket& asStartPacket() const;

    //! Get this as a DataPacket
    //!
    const DataPacket& asDataPacket() const;

    //! Get this as an EndPacket
    //!
    const EndPacket& asEndPacket() const;

    //! Get this as a CancelPacket
    //!
    const CancelPacket& asCancelPacket() const;

    //! Initialize this with a StartPacket
    //!
    void fromStartPacket(const StartPacket& startPacket);

    //! Initialize this with a DataPacket
    //!
    void fromDataPacket(const DataPacket& dataPacket);

    //! Initialize this with an EndPacket
    //!
    void fromEndPacket(const EndPacket& endPacket);

    //! Initialize this with a CancelPacket
    //!
    void fromCancelPacket(const CancelPacket& cancelPacket);

    //! Get the buffer size needed to hold this FilePacket
    //!
    U32 bufferSize() const;

    //! Convert this FilePacket to a Buffer
    //!
    SerializeStatus toBuffer(Buffer& buffer) const;

  private:
    // ----------------------------------------------------------------------
    // Private methods
    // ----------------------------------------------------------------------

    //! Initialize this from a SerialBuffer
    //!
    SerializeStatus fromSerialBuffer(SerialBuffer& serialBuffer);

  private:
    // ----------------------------------------------------------------------
    // Private data
    // ----------------------------------------------------------------------

    //! this, seen as a header
    //!
    Header m_header;

    //! this, seen as a Start packet
    //!
    StartPacket m_startPacket;

    //! this, seen as a Data packet
    //!
    DataPacket m_dataPacket;

    //! this, seen as an End packet
    //!
    EndPacket m_endPacket;

    //! this, seen as a Cancel packet
    //!
    CancelPacket m_cancelPacket;
};

}  // namespace Fw

#endif