/*
 * Copyright (c) 1999-2000, Eric Moon.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions, and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


// RawBuffer.cpp
// e.moon 31mar99

#include "RawBuffer.h"

#include <RealtimeAlloc.h>
#include <Debug.h>
#include <cstring>

// -------------------------------------------------------- //
// ctor/dtor/accessors
// -------------------------------------------------------- //

// allocate buffer (if frames > 0)
RawBuffer::RawBuffer(
        uint32 frameSize,
        uint32 frames,
        bool bCircular,
        rtm_pool* pFromPool) :
        
        m_pData(0),
        m_pPool(pFromPool),
        m_frameSize(frameSize),
        m_frames(frames),
        m_allocatedSize(0),
        m_bCircular(bCircular),
        m_bOwnData(true)
{
        
        if(m_frames)
                resize(m_frames);
}
                
// point to given data (does NOT take responsibility for
// deleting it; use adopt() for that.)
RawBuffer::RawBuffer(
        void* pData,
        uint32 frameSize,
        uint32 frames,
        bool bCircular,
        rtm_pool* pFromPool) :
                
        m_pData(pData),
        m_pPool(pFromPool),
        m_frameSize(frameSize),
        m_frames(frames),
        m_allocatedSize(0),
        m_bCircular(bCircular),
        m_bOwnData(false)
{}

RawBuffer::RawBuffer(const RawBuffer& clone) {
        operator=(clone);
}

// generate a reference to the buffer
RawBuffer& RawBuffer::operator=(const RawBuffer& clone) {
        m_pData = clone.m_pData;
        m_allocatedSize = clone.m_allocatedSize;
        m_frameSize = clone.m_frameSize;
        m_frames = clone.m_frames;
        m_bCircular = clone.m_bCircular;
        m_pPool = clone.m_pPool;
        m_bOwnData = false;

        return *this;
}

// deallocate if I own the data
RawBuffer::~RawBuffer() {
        free();
}

char* RawBuffer::data() const { return (char*)m_pData; }
// returns pointer to given frame
char* RawBuffer::frame(uint32 frame) const {
        return data() + (frame * frameSize());
}
uint32 RawBuffer::frameSize() const { return m_frameSize; }
uint32 RawBuffer::frames() const { return m_frames; }
uint32 RawBuffer::size() const { return m_frames * m_frameSize; }

bool RawBuffer::isCircular() const { return m_bCircular; }
bool RawBuffer::ownsBuffer() const { return m_bOwnData; }

rtm_pool* RawBuffer::pool() const { return m_pPool; }

// resize buffer, re-allocating if necessary to contain
// designated number of frames.
// Does not preserve buffer contents.
        
void RawBuffer::resize(uint32 frames) {
        uint32 sizeRequired = frames * m_frameSize;
        
        // already have enough storage?
        if(sizeRequired         < m_allocatedSize &&
                m_bOwnData) {
                m_frames = frames;
                return;
        }

        // free existing storage
        free();         
        
        // allocate
        m_pData = (m_pPool) ?
                rtm_alloc(m_pPool, sizeRequired) :
                new int8[sizeRequired];
                
        m_bOwnData = true;
        m_allocatedSize = sizeRequired;
        m_frames = frames;
        
}
        
// take ownership of buffer from target
// (deletes current buffer data, if any owned)

void RawBuffer::adopt(
        void* pData,
        uint32 frameSize,
        uint32 frames,
        bool bCircular,
        rtm_pool* pPool) {

        // clean up myself first
        free();
        
        // reference
        operator=(RawBuffer(pData, frameSize, frames, bCircular, pPool));

        // mark ownership
        m_bOwnData = true;
}

// returns false if the target doesn't own the data, but references it
// one way or the other

bool RawBuffer::adopt(RawBuffer& target) {

        // reference
        operator=(target);

        // take ownership if possible
        
        if(!target.m_bOwnData) {
                m_bOwnData = false;
                return false;
        }

        target.m_bOwnData = false;
        m_bOwnData = true;
        return true;
}
        
// adopt currently ref'd data (if any; returns false if no buffer data or
// already owned)

bool RawBuffer::adopt() {
        if(!m_pData || m_bOwnData)
                return false;
        
        m_bOwnData = true;
        return true;
}

// -------------------------------------------------------- //
// operations
// -------------------------------------------------------- //

// fill the buffer with zeroes
        
void RawBuffer::zero() {
        if(!m_pData || !m_frames)
                return;
        
        memset(m_pData, 0, m_frames * m_frameSize);
}

// raw copy to destination buffer, returning the number of
// frames written, and adjusting both offsets accordingly.
//
// no frames will be written if the buffers' frame sizes
// differ.
        
uint32 RawBuffer::rawCopyTo(
        RawBuffer& target,
        uint32* pioFromFrame,
        uint32* pioTargetFrame,
        uint32 frames) const {

        if(m_frameSize != target.m_frameSize)
                return 0;
        
        ASSERT(m_pData);
        ASSERT(m_frames);
        ASSERT(target.m_pData);

        // convert frame counts to byte offsets
        uint32 fromOffset = *pioFromFrame * m_frameSize;
        uint32 targetOffset = *pioTargetFrame * m_frameSize;

        // figure buffer sizes in bytes
        uint32 size = m_frames * m_frameSize;   
        uint32 targetSize = target.m_frames * target.m_frameSize;

        // figure amount to write       
        uint32 toCopy = frames * m_frameSize;   
        if(target.m_bCircular) {
                if(toCopy > targetSize)
                        toCopy = targetSize;
        } else {
                if(toCopy > (targetSize-targetOffset))
                        toCopy = (targetSize-targetOffset);
        }
        uint32 remaining = toCopy;

        // do it
        while(remaining) {
        
                // figure a contiguous area to fill
                uint32 targetChunk = targetSize - targetOffset;
        
                if(targetChunk > remaining)
                        targetChunk = remaining;        

                // fill it (from one or more source areas)
                while(targetChunk > 0) {
                
                        // figure a contiguous source area
                        uint32 sourceChunk = size - fromOffset;
                        if(sourceChunk > targetChunk)
                                sourceChunk = targetChunk;
        
                        // copy it
                        memcpy(
                                (int8*)target.m_pData + targetOffset,
                                (int8*)m_pData + fromOffset,
                                sourceChunk);
        
                        // advance offsets
                        targetOffset += sourceChunk;
                        if(targetOffset == targetSize)
                                targetOffset = 0;
                        
                        fromOffset += sourceChunk;
                        if(fromOffset == size)
                                fromOffset = 0;

                        // figure remaining portion of target area to fill                              
                        targetChunk -= sourceChunk;
                        remaining -= sourceChunk;
                }       
        }
        
        // write new offsets
        *pioFromFrame = fromOffset / m_frameSize;
        *pioTargetFrame = targetOffset / m_frameSize;
        
        return toCopy;
}
        
// more convenient version of above if you don't care
// how the offsets change.

uint32 RawBuffer::rawCopyTo(
        RawBuffer& target,
        uint32 fromOffset,
        uint32 targetOffset,
        uint32 frames) const {
        
        return rawCopyTo(target, &fromOffset, &targetOffset, frames);
}

// -------------------------------------------------------- //
// internal operations
// -------------------------------------------------------- //

// free owned data, if any
// [16jun99] uses proper rtm_free() call if needed
void RawBuffer::free() {
        if(!(m_bOwnData && m_pData))
                return;
                
        if(m_pPool)
                rtm_free(m_pData);
        else
                delete [] (int8 *)m_pData;
                
        m_pData = 0;
}


// END -- RawBuffer.cpp --