/*
 * Copyright (c) 2011 Samsung Electronics Co., Ltd All Rights Reserved
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "face.h"
#include "face_priv.h"

#include <stdlib.h>



static void convert_RGB565_to_Y(unsigned char* pBuf, unsigned char* pGrayBuf, int width, int height)
{
	unsigned char* pDst, * pEnd;
	unsigned short* pSrc;

	unsigned short R, G, B;
	long lt;

	pSrc = (unsigned short*) pBuf;
	pDst = (unsigned char*) pGrayBuf;
	pEnd = (unsigned char*) ((unsigned char*) pGrayBuf + height * width);

	while (pDst < pEnd)
	{
		R = (unsigned char) ((*pSrc >> 11) << 3);            // R
		G = (unsigned char) ((*pSrc & 0x07e0) >> 3);         // +G
		B = (unsigned char) ((*pSrc++ & 0x001f) << 3);           // +B

		// Y = 0.299 R + 0.587 G + 0.114 B
		lt = (306L * (long) R + 601L * (long) G + 117L * (long) B);
		*pDst++ = (unsigned char ) (lt >> 10);
		//(BYTE)(((int)R+(int)G+(int)B) /3);
	}
}

static void convert_RGBA8888_to_Y(unsigned char* pBuf, unsigned char* pGrayBuf, int width, int height)
{
	unsigned long* pSrc = (unsigned long*) pBuf;
	unsigned char* pDSt = (unsigned char*) pGrayBuf;
	unsigned char* pEnd = pDSt + height * width;

	while (pDSt < pEnd)
	{
		unsigned long r = (*pSrc >> 16) & 0xFF;
		unsigned long g = (*pSrc >> 8) & 0xFF;
		unsigned long b = (*pSrc++) & 0xFF;

		*pDSt++ = (308 * r + 600 * g + 116 * b) >> 10;
	}
}

#define CLIP(a) ((a) > 255 ? 255 : (a) < 0 ? 0 : (a))

#if 0
static void convert_RGB888_to_Y(unsigned char* pBuf, unsigned char* pGrayBuf, int width, int height)
{
	unsigned char* pSrc = (unsigned char*) pBuf;
	unsigned char* pDSt = (unsigned char*) pGrayBuf;

	unsigned char* pEnd = pDSt + height * width;

	while (pDSt < pEnd)
	{
		unsigned long r = *pSrc++;
		unsigned long g = *pSrc++;
		unsigned long b = *pSrc++;

		*pDSt++ = (308 * r + 600 * g + 116 * b) >> 10;
	}
}
#endif

static bool _validate_face_image_h(face_image_h face_image)
{
	if ( face_image == NULL )
	{
		return false;
	}

	if ( face_image->magic != FACE_IMAGE_MAGIC )
	{
		return false;
	}

	return true;
}


EXPORT_API int face_image_create(__in face_image_colorspace_e colorspace, __in unsigned char *buffer, __in int width, __in int height, __in int size, __out face_image_h *face_image)
{
	if ( face_image == NULL )
	{
		LOG_ERROR("Out pointer is NULL. %s", _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	if ( buffer == NULL )
	{
		LOG_ERROR("Buffer Cannot be NULL. %s", _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	if ( width <= 0 || height  <= 0 )
	{
		LOG_ERROR("Invalid image size(%d,%d). %s", width, height, _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	unsigned char *YBuf = NULL;

	switch(colorspace)
	{
		case FACE_IMAGE_COLORSPACE_YUV420:
			YBuf = buffer;
			break;

		case FACE_IMAGE_COLORSPACE_RGB565:
			YBuf = (unsigned char *)calloc(1, width * height);
			if ( YBuf == NULL )
			{
				LOG_ERROR("Cannot allocate FACE_IMAGE_COLORSPACE_RGB565 buffer");
				return FACE_ERROR_OUT_OF_MEMORY;
			}

			convert_RGB565_to_Y(buffer, YBuf, width, height);
			break;

		case FACE_IMAGE_COLORSPACE_RGBA8888:
			YBuf = (unsigned char *)calloc(1, width * height);
			if ( YBuf == NULL )
			{
				LOG_ERROR("Cannot allocate FACE_IMAGE_COLORSPACE_RGBA8888 buffer");
				return FACE_ERROR_OUT_OF_MEMORY;
			}

			convert_RGBA8888_to_Y(buffer, YBuf, width, height);
			break;

		case FACE_IMAGE_COLORSPACE_LUMINANCE_ONLY:
			YBuf = buffer;
			break;
		default:
			LOG_ERROR("Invalid colorspace(%d). %s", colorspace, _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
			return FACE_ERROR_INVALID_PARAMTER;
	}

	*face_image = (FaceImage *)calloc(1, sizeof(FaceImage));

	if ( *face_image == NULL )
	{
		LOG_ERROR("Cannot allocate face_image_h");
		return FACE_ERROR_OUT_OF_MEMORY;
	}

	(*face_image)->magic = FACE_IMAGE_MAGIC;

	(*face_image)->pixel = YBuf;
	(*face_image)->width = width;
	(*face_image)->height = height;
	(*face_image)->size = width * height;
	(*face_image)->colorspace = colorspace;

	return FACE_ERROR_NONE;
}


EXPORT_API int face_image_destroy(face_image_h face_image)
{
	if ( _validate_face_image_h(face_image) == false )
	{
		LOG_ERROR("Invalid image handle. %s", _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	if ( face_image->colorspace == FACE_IMAGE_COLORSPACE_RGB565 || face_image->colorspace == FACE_IMAGE_COLORSPACE_RGBA8888)
	{
		free(face_image->pixel);	// Free user buffer
	}

	face_image->pixel = NULL;
	face_image->magic = FACE_INVALID_MAGIC;

	free(face_image);

	return FACE_ERROR_NONE;
}


#if 0
EXPORT_API int face_image_set_data( face_image_h face_image,
                             face_image_colorspace_e colorspace, unsigned char *buffer, int width, int height, int size)
{

// Check Param.
	if ( _validate_face_image_h(face_image) == false )
	{
		LOG_ERROR("Invalid image handle. %s", _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	if ( buffer == NULL )
	{
		LOG_ERROR("Invalid image data. %s", width, height, _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	if ( width <= 0 || height  <= 0 )
	{
		LOG_ERROR("Invalid image size(%d,%d). %s", width, height, _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	if ( colorspace != FACE_IMAGE_COLORSPACE_LUMINANCE_ONLY)
	{
		LOG_ERROR("Invalid image format(%d). %s", colorspace , _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	face_image->pixel = buffer;
	face_image->width = width;
	face_image->height = height;
	face_image->size = width * height;
	face_image->colorspace = colorspace;

	return FACE_ERROR_NONE;

}



EXPORT_API int face_image_get_data(face_image_h face_image,
                            face_image_colorspace_e *colorspace, unsigned char **buffer, int *width, int *height, int *size)
{
	if ( _validate_face_image_h(face_image) == false )
	{
		LOG_ERROR("Invalid image handle. %s", _face_convert_error(FACE_ERROR_INVALID_PARAMTER));
		return FACE_ERROR_INVALID_PARAMTER;
	}

	if ( colorspace == NULL || buffer == NULL || width == NULL || height == NULL )
	{
		LOG_ERROR("Invalid param. 0x%08x 0x%08x 0x%08x 0x%08x", colorspace, buffer, width, height);
		return FACE_ERROR_INVALID_PARAMTER;
	}

	*buffer = face_image->pixel;
	*width = face_image->width;
	*height = face_image->height;
	*colorspace = face_image->colorspace;
	*size = face_image->size;

	return FACE_ERROR_NONE;
}
#endif