/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: HashStream.hpp
    Date: 2021-6-10
    Author: Reece
***/
#pragma once

namespace Aurora::Hashing
{
    struct IHashStream
    {
        /**
         * @brief Processes an arbitrary amount of bytes
         * @param input
        */
        virtual void Ingest(const Memory::MemoryViewRead &input) = 0;

        /**
         * @brief Legacy pointer variant of the ::Finalize API. Wont deprecate.
         * @param length
         * @return
        */
        virtual AuUInt8 const* GetBytes(AuUInt32 &uLength) = 0;

        /**
         * @brief Finalizes the stream - locks and returns the internal buffer
         * @return
        */
        virtual Memory::MemoryViewRead Finalize() = 0;

        /**
         * @brief 1) Temporarily finalizes the stream
         *        2) Copies the final state into the final buffer
         *        3) Returns the stream its' original state
         *        4) Returns a view of the final buffer
         * @return 
        */
        virtual Memory::MemoryViewRead PeekFinalize() = 0;

        /**
         * @brief Exports the state of an aligned stream
         * @return
        */
        virtual AuResult<Memory::MemoryViewRead> Export() = 0;

        /**
         * @brief Starts off from where ::Export left off
         * @param view
         * @return
        */
        virtual bool Import(const Memory::MemoryViewRead &view) = 0;

        /**
         * @brief Reuse the IHashStream of the EHashType variant by resetting the stream state to its' default configuration
        */
        virtual void Reset() = 0;
    };
    
    AUKN_SHARED_API(HashStream, IHashStream, EHashType type);
}