/** 
 * @file llimagej2coj.cpp
 * @brief This is an implementation of JPEG2000 encode/decode using OpenJPEG.
 *
 * Copyright (c) 2006-$CurrentYear$, Linden Research, Inc.
 * $License$
 */

#include "linden_common.h"
#include "llimagej2coj.h"

// this is defined so that we get static linking.
#include "openjpeg/openjpeg.h"

#include "lltimer.h"
#include "llmemory.h"

LLImageJ2CImpl* fallbackCreateLLImageJ2CImpl()
{
	return new LLImageJ2COJ();
}

void fallbackDestroyLLImageJ2CImpl(LLImageJ2CImpl* impl)
{
	delete impl;
	impl = NULL;
}

/**
sample error callback expecting a FILE* client object
*/
void error_callback(const char* msg, void*)
{
	lldebugs << "LLImageJ2CImpl error_callback: " << msg << llendl;
}
/**
sample warning callback expecting a FILE* client object
*/
void warning_callback(const char* msg, void*)
{
	lldebugs << "LLImageJ2CImpl warning_callback: " << msg << llendl;
}
/**
sample debug callback expecting no client object
*/
void info_callback(const char* msg, void*)
{
	lldebugs << "LLImageJ2CImpl info_callback: " << msg << llendl;
}


LLImageJ2COJ::LLImageJ2COJ() : LLImageJ2CImpl()
{
}


LLImageJ2COJ::~LLImageJ2COJ()
{
}


BOOL LLImageJ2COJ::decodeImpl(LLImageJ2C &base, LLImageRaw &raw_image, F32 decode_time, S32 first_channel, S32 max_channel_count)
{
	//
	// FIXME: Get the comment field out of the texture
	//

	LLTimer decode_timer;

	opj_dparameters_t parameters;	/* decompression parameters */
	opj_event_mgr_t event_mgr;		/* event manager */
	opj_image_t *image = NULL;

	opj_dinfo_t* dinfo = NULL;	/* handle to a decompressor */
	opj_cio_t *cio = NULL;


	/* configure the event callbacks (not required) */
	memset(&event_mgr, 0, sizeof(opj_event_mgr_t));
	event_mgr.error_handler = error_callback;
	event_mgr.warning_handler = warning_callback;
	event_mgr.info_handler = info_callback;

	/* set decoding parameters to default values */
	opj_set_default_decoder_parameters(&parameters);

	parameters.cp_reduce = base.getRawDiscardLevel();

	/* decode the code-stream */
	/* ---------------------- */

	/* JPEG-2000 codestream */

	/* get a decoder handle */
	dinfo = opj_create_decompress(CODEC_J2K);

	/* catch events using our callbacks and give a local context */
	opj_set_event_mgr((opj_common_ptr)dinfo, &event_mgr, stderr);			

	/* setup the decoder decoding parameters using user parameters */
	opj_setup_decoder(dinfo, &parameters);

	/* open a byte stream */
	cio = opj_cio_open((opj_common_ptr)dinfo, base.getData(), base.getDataSize());

	/* decode the stream and fill the image structure */
	image = opj_decode(dinfo, cio);

	/* close the byte stream */
	opj_cio_close(cio);

	/* free remaining structures */
	if(dinfo)
	{
		opj_destroy_decompress(dinfo);
	}

	// The image decode failed if the return was NULL or the component
	// count was zero.  The latter is just a sanity check before we
	// dereference the array.
	if(!image || !image->numcomps)
	{
		fprintf(stderr, "ERROR -> decodeImpl: failed to decode image!\n");
		if (image)
			opj_image_destroy(image);

		return TRUE; // done
	}

	// Copy image data into our raw image format (instead of the separate channel format

	S32 img_components = image->numcomps;
	S32 channels = img_components - first_channel;
	if( channels > max_channel_count )
		channels = max_channel_count;

	// Component buffers are allocated in an image width by height buffer.
	// The image placed in that buffer is ceil(width/2^factor) by
	// ceil(height/2^factor) and if the factor isn't zero it will be at the
	// top left of the buffer with black filled in the rest of the pixels.
	// It is integer math so the formula is written in ceildivpo2.
	// (Assuming all the components have the same width, height and
	// factor.)
	S32 comp_width = image->comps[0].w;
	S32 f=image->comps[0].factor;
	S32 width = ceildivpow2(image->x1 - image->x0, f);
	S32 height = ceildivpow2(image->y1 - image->y0, f);
	raw_image.resize(width, height, channels);
	U8 *rawp = raw_image.getData();

	// first_channel is what channel to start copying from
	// dest is what channel to copy to.  first_channel comes from the
	// argument, dest always starts writing at channel zero.
	for (S32 comp = first_channel, dest=0; comp < first_channel + channels;
		comp++, dest++)
	{
		S32 offset = dest;
		for (S32 y = (height - 1); y >= 0; y--)
		{
			for (S32 x = 0; x < width; x++)
			{
				rawp[offset] = image->comps[comp].data[y*comp_width + x];
				offset += channels;
			}
		}
	}

	/* free image data structure */
	opj_image_destroy(image);

	return TRUE; // done
}


BOOL LLImageJ2COJ::encodeImpl(LLImageJ2C &base, const LLImageRaw &raw_image, const char* comment_text, F32 encode_time, BOOL reversible)
{
	const S32 MAX_COMPS = 5;
	opj_cparameters_t parameters;	/* compression parameters */
	opj_event_mgr_t event_mgr;		/* event manager */


	/* 
	configure the event callbacks (not required)
	setting of each callback is optional 
	*/
	memset(&event_mgr, 0, sizeof(opj_event_mgr_t));
	event_mgr.error_handler = error_callback;
	event_mgr.warning_handler = warning_callback;
	event_mgr.info_handler = info_callback;

	/* set encoding parameters to default values */
	opj_set_default_encoder_parameters(&parameters);
	parameters.tcp_rates[0] = 0;
	parameters.tcp_numlayers++;
	parameters.cp_disto_alloc = 1;
	parameters.cod_format = 0;
	if (!comment_text)
	{
		parameters.cp_comment = "";
	}
	else
	{
		// Awful hacky cast, too lazy to copy right now.
		parameters.cp_comment = (char *)comment_text;
	}

	//
	// Fill in the source image from our raw image
	//
	OPJ_COLOR_SPACE color_space = CLRSPC_SRGB;
	opj_image_cmptparm_t cmptparm[MAX_COMPS];
	opj_image_t * image = NULL;
	S32 numcomps = raw_image.getComponents();
	S32 width = raw_image.getWidth();
	S32 height = raw_image.getHeight();

	memset(&cmptparm[0], 0, MAX_COMPS * sizeof(opj_image_cmptparm_t));
	for(S32 c = 0; c < numcomps; c++) {
		cmptparm[c].prec = 8;
		cmptparm[c].bpp = 8;
		cmptparm[c].sgnd = 0;
		cmptparm[c].dx = parameters.subsampling_dx;
		cmptparm[c].dy = parameters.subsampling_dy;
		cmptparm[c].w = width;
		cmptparm[c].h = height;
	}

	/* create the image */
	image = opj_image_create(numcomps, &cmptparm[0], color_space);

	image->x1 = width;
	image->y1 = height;

	S32 i = 0;
	const U8 *src_datap = raw_image.getData();
	for (S32 y = height - 1; y >= 0; y--)
	{
		for (S32 x = 0; x < width; x++)
		{
			const U8 *pixel = src_datap + (y*width + x) * numcomps;
			for (S32 c = 0; c < numcomps; c++)
			{
				image->comps[c].data[i] = *pixel;
				pixel++;
			}
			i++;
		}
	}



	/* encode the destination image */
	/* ---------------------------- */

	int codestream_length;
	opj_cio_t *cio = NULL;

	/* get a J2K compressor handle */
	opj_cinfo_t* cinfo = opj_create_compress(CODEC_J2K);

	/* catch events using our callbacks and give a local context */
	opj_set_event_mgr((opj_common_ptr)cinfo, &event_mgr, stderr);			

	/* setup the encoder parameters using the current image and using user parameters */
	opj_setup_encoder(cinfo, &parameters, image);

	/* open a byte stream for writing */
	/* allocate memory for all tiles */
	cio = opj_cio_open((opj_common_ptr)cinfo, NULL, 0);

	/* encode the image */
	bool bSuccess = opj_encode(cinfo, cio, image, parameters.index);
	if (!bSuccess)
	{
		opj_cio_close(cio);
		llinfos << "Failed to encode image." << llendl;
		return FALSE;
	}
	codestream_length = cio_tell(cio);

	base.copyData(cio->buffer, codestream_length);
	base.updateData(); // set width, height

	/* close and free the byte stream */
	opj_cio_close(cio);

	/* free remaining compression structures */
	opj_destroy_compress(cinfo);


	/* free user parameters structure */
	if(parameters.cp_matrice) free(parameters.cp_matrice);

	/* free image data */
	opj_image_destroy(image);
	return TRUE;
}

BOOL LLImageJ2COJ::getMetadata(LLImageJ2C &base)
{
	//
	// FIXME: We get metadata by decoding the ENTIRE image.
	//

	// Update the raw discard level
	base.updateRawDiscardLevel();

	opj_dparameters_t parameters;	/* decompression parameters */
	opj_event_mgr_t event_mgr;		/* event manager */
	opj_image_t *image = NULL;

	opj_dinfo_t* dinfo = NULL;	/* handle to a decompressor */
	opj_cio_t *cio = NULL;


	/* configure the event callbacks (not required) */
	memset(&event_mgr, 0, sizeof(opj_event_mgr_t));
	event_mgr.error_handler = error_callback;
	event_mgr.warning_handler = warning_callback;
	event_mgr.info_handler = info_callback;

	/* set decoding parameters to default values */
	opj_set_default_decoder_parameters(&parameters);

	// Only decode what's required to get the size data.
	parameters.cp_limit_decoding=LIMIT_TO_MAIN_HEADER;

	//parameters.cp_reduce = mRawDiscardLevel;

	/* decode the code-stream */
	/* ---------------------- */

	/* JPEG-2000 codestream */

	/* get a decoder handle */
	dinfo = opj_create_decompress(CODEC_J2K);

	/* catch events using our callbacks and give a local context */
	opj_set_event_mgr((opj_common_ptr)dinfo, &event_mgr, stderr);			

	/* setup the decoder decoding parameters using user parameters */
	opj_setup_decoder(dinfo, &parameters);

	/* open a byte stream */
	cio = opj_cio_open((opj_common_ptr)dinfo, base.getData(), base.getDataSize());

	/* decode the stream and fill the image structure */
	image = opj_decode(dinfo, cio);

	/* close the byte stream */
	opj_cio_close(cio);

	/* free remaining structures */
	if(dinfo)
	{
		opj_destroy_decompress(dinfo);
	}

	if(!image)
	{
		fprintf(stderr, "ERROR -> getMetadata: failed to decode image!\n");
		return FALSE;
	}

	// Copy image data into our raw image format (instead of the separate channel format
	S32 width = 0;
	S32 height = 0;

	S32 img_components = image->numcomps;
	width = image->x1 - image->x0;
	height = image->y1 - image->y0;
	base.setSize(width, height, img_components);

	/* free image data structure */
	opj_image_destroy(image);
	return TRUE;
}