/*
* All or portions of this file Copyright (c) Amazon.com, Inc. or its affiliates or
* its licensors.
*
* For complete copyright and license terms please see the LICENSE at the root of this
* distribution (the "License"). All use of this software is governed by the License,
* or, if provided, by the license below or the license accompanying this file. Do not
* remove or modify any license notices. This file is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*
*/
// Original file Copyright Crytek GMBH or its affiliates, used under license.

// Description : Provides the interface for the zlib inflate wrapper


#ifndef CRYINCLUDE_CRYCOMMON_IZLIBDECOMPRESSOR_H
#define CRYINCLUDE_CRYCOMMON_IZLIBDECOMPRESSOR_H
#pragma once


enum EZInflateState
{
    eZInfState_AwaitingInput,       // caller must call Input() to continue
    eZInfState_Inflating,               // caller must wait
    eZInfState_ConsumeOutput,       // caller must consume output and then call SetOutputBuffer() to continue
    eZInfState_Finished,                // caller must call Release()
    eZInfState_Error                        // error has occurred and the stream has been closed and will no longer compress
};

struct IZLibInflateStream
{
protected:
    virtual ~IZLibInflateStream() {}; // use Release()

public:
    struct SStats
    {
        int bytesInput;
        int bytesOutput;
        int curMemoryUsed;
        int peakMemoryUsed;
    };

    // Description:
    //   Specifies the output buffer for the inflate operation
    //   Should be set before providing input
    //   The specified buffer must remain valid (ie do not free) whilst compression is in progress (state == eZInfState_Inflating)
    virtual void SetOutputBuffer(char* pInBuffer, unsigned int inSize) = 0;

    // Description:
    //   Returns the number of bytes from the output buffer that are ready to be consumed. After consuming any output, you should call SetOutputBuffer() again to mark the buffer as available
    virtual unsigned int GetBytesOutput() = 0;

    // Description:
    //   Begins decompressing the source data pInSource of length inSourceSize to a previously specified output buffer
    //   Only valid to be called if the stream is in state eZInfState_AwaitingInput
    //   The specified buffer must remain valid (ie do not free) whilst compression is in progress (state == eZInfState_Inflating)
    virtual void Input(const char* pInSource, unsigned int inSourceSize) = 0;

    // Description:
    //   Finishes the compression, causing all data to be flushed to the output buffer
    //   Once called no more data can be input
    //   After calling the caller must wait until GetState() reuturns eZInfState_Finished
    virtual void EndInput() = 0;

    // Description:
    //   Returns the state of the stream,
    virtual EZInflateState GetState() = 0;

    // Description:
    //   Gets stats on inflate stream, valid to call at anytime
    virtual void GetStats(SStats* pOutStats) = 0;

    // Description:
    //   Deletes the inflate stream. Will assert if stream is in an invalid state to be released (in state eZInfState_Inflating)
    virtual void Release() = 0;
};

struct IZLibDecompressor
{
protected:
    virtual ~IZLibDecompressor()    {};     // use Release()

public:
    // Description:
    //   Creates a inflate stream to decompress data using zlib
    virtual IZLibInflateStream* CreateInflateStream() = 0;

    virtual void Release() = 0;
};

#endif // CRYINCLUDE_CRYCOMMON_IZLIBDECOMPRESSOR_H