#include "HGBmp.h"
#include "../base/HGInc.h"
extern "C"
{
#include "libnsbmp.h"
};

HGResult HGAPI HGImgFmt_CheckBmpFile(const HGChar* fileName, HGBool* isBmp)
{
	if (NULL == fileName || NULL == isBmp)
	{
		return HGBASE_ERR_INVALIDARG;
	}

	HGBmpLoadInfo info;
	HGResult ret = HGImgFmt_LoadBmpImage(fileName, &info, 0, 0, NULL);
	*isBmp = (HGBASE_ERR_OK == ret ? HGTRUE : HGFALSE);
	return HGBASE_ERR_OK;
}

static void* bitmap_create(int width, int height, unsigned int state)
{
	if (width <= 0 || height <= 0)
	{
		return NULL;
	}

	(void)state;  /* unused */
	return calloc((intptr_t)width * (intptr_t)height, 4);
}

static unsigned char* bitmap_get_buffer(void* bitmap)
{
	assert(NULL != bitmap);
	return (unsigned char*)bitmap;
}

static size_t bitmap_get_bpp(void* bitmap)
{
	(void)bitmap;  /* unused */
	return 4;
}

static void bitmap_destroy(void* bitmap)
{
	assert(NULL != bitmap);
	free(bitmap);
}

HGResult HGAPI HGImgFmt_LoadBmpImage(const HGChar* fileName, HGBmpLoadInfo* info,
	HGUInt imgType, HGUInt imgOrigin, HGImage* image)
{
	if (NULL == fileName)
	{
		return HGBASE_ERR_INVALIDARG;
	}

	if (NULL == image)
	{
		if (0 != imgType || 0 != imgOrigin)
		{
			return HGBASE_ERR_INVALIDARG;
		}
	}
	else
	{
		if (0 != imgType && HGBASE_IMGTYPE_GRAY != imgType && HGBASE_IMGTYPE_RGB != imgType
			&& HGBASE_IMGTYPE_RGBA != imgType && HGBASE_IMGTYPE_BGR != imgType
			&& HGBASE_IMGTYPE_BGRA != imgType)
		{
			return HGBASE_ERR_INVALIDARG;
		}

		if (HGBASE_IMGORIGIN_TOP != imgOrigin && HGBASE_IMGORIGIN_BOTTOM != imgOrigin)
		{
			return HGBASE_ERR_INVALIDARG;
		}
	}

	FILE* file = fopen(fileName, "rb");
	if (NULL == file)
	{
		return HGBASE_ERR_ACCESSDENIED;
	}

#if defined(HG_CMP_MSC)
	_fseeki64(file, 0, SEEK_END);
	uint64_t size = _ftelli64(file);
#else
	fseeko64(file, 0, SEEK_END);
	uint64_t size = ftello64(file);
#endif
	if (0 == size)
	{
		fclose(file);
		file = NULL;
		return HGBASE_ERR_FAIL;
	}

	uint8_t* buffer = (uint8_t*)malloc((size_t)size);
	if (NULL == buffer)
	{
		fclose(file);
		file = NULL;
		return HGBASE_ERR_FAIL;
	}

#if defined(HG_CMP_MSC)
	_fseeki64(file, 0, SEEK_SET);
#else
	fseeko64(file, 0, SEEK_SET);
#endif
	size_t readSize = fread(buffer, 1, (size_t)size, file);
	if (readSize != size)
	{
		free(buffer);
		buffer = NULL;
		fclose(file);
		file = NULL;
		return HGBASE_ERR_FAIL;
	}

	bmp_image bmp;
	bmp_bitmap_callback_vt bitmap_callbacks = { bitmap_create, bitmap_destroy, bitmap_get_buffer, bitmap_get_bpp };
	bmp_create(&bmp, &bitmap_callbacks);

	if (BMP_OK != bmp_analyse(&bmp, (size_t)size, buffer))
	{
		bmp_finalise(&bmp);
		free(buffer);
		buffer = NULL;
		fclose(file);
		file = NULL;
		return HGBASE_ERR_FAIL;
	}

	if (NULL != info)
	{
		info->width = bmp.width;
		info->height = bmp.height;
		info->bitCount = bmp.bpp;
		info->compression = (uint32_t)bmp.encoding;
		info->xPelsPerMeter = bmp.x_pels_per_meter;
		info->yPelsPerMeter = bmp.y_pels_per_meter;
	}

	if (NULL != image)
	{
		if (BMP_OK != bmp_decode(&bmp))
		{
			bmp_finalise(&bmp);
			free(buffer);
			buffer = NULL;
			fclose(file);
			file = NULL;
			return HGBASE_ERR_FAIL;
		}

		if (0 == imgType)
		{
			if (32 == bmp.bpp)
			{
				imgType = HGBASE_IMGTYPE_RGBA;
			}
			else
			{
				imgType = HGBASE_IMGTYPE_RGB;
			}
		}

		HGImage image2 = NULL;
		if (HGBASE_ERR_OK != HGBase_CreateImage(bmp.width, bmp.height, imgType, imgOrigin, &image2))
		{
			bmp_finalise(&bmp);
			free(buffer);
			buffer = NULL;
			fclose(file);
			file = NULL;
			return HGBASE_ERR_FAIL;
		}

		uint32_t xDpi = (uint32_t)((double)bmp.x_pels_per_meter / 39.3700787 + 0.5);
		uint32_t yDpi = (uint32_t)((double)bmp.y_pels_per_meter / 39.3700787 + 0.5);
		HGBase_SetImageDpi(image2, xDpi, yDpi);

		uint8_t* data;
		HGBase_GetImageData(image2, &data);
		HGImageInfo imgInfo;
		HGBase_GetImageInfo(image2, &imgInfo);

		HGByte* src = (HGByte*)bmp.bitmap;
		HGByte* dest = data;
		HGSize destStep = (HGSize)imgInfo.widthStep;
		if (HGBASE_IMGORIGIN_BOTTOM == imgOrigin)
		{
			dest = data + (HGUSize)(bmp.height - 1) * (HGUSize)imgInfo.widthStep;
			destStep = -(HGSize)imgInfo.widthStep;
		}

		if (HGBASE_IMGTYPE_GRAY == imgType)
		{
			//#pragma omp parallel for
			for (int32_t i = 0; i < (int32_t)bmp.height; i++)
			{
				uint8_t* pEx = src + (HGSize)i * (HGSize)(bmp.width * 4);
				uint8_t* pExEnd = pEx + bmp.width * 4;
				uint8_t* pDestEx = dest + (HGSize)i * (HGSize)destStep;

				while (pEx < pExEnd)
				{
					uint8_t value = (pEx[0] * 76 + pEx[1] * 150 + pEx[2] * 30) >> 8;
					*pDestEx = value;

					pEx += 4;
					++pDestEx;
				}
			}
		}
		else if (HGBASE_IMGTYPE_RGB == imgType)
		{
			//#pragma omp parallel for
			for (int32_t i = 0; i < (int32_t)bmp.height; i++)
			{
				uint8_t* pEx = src + (HGSize)i * (HGSize)(bmp.width * 4);
				uint8_t* pExEnd = pEx + bmp.width * 4;
				uint8_t* pDestEx = dest + (HGSize)i * (HGSize)destStep;

				while (pEx < pExEnd)
				{
					pDestEx[0] = pEx[0];
					pDestEx[1] = pEx[1];
					pDestEx[2] = pEx[2];

					pEx += 4;
					pDestEx += 3;
				}
			}
		}
		else if (HGBASE_IMGTYPE_BGR == imgType)
		{
			//#pragma omp parallel for
			for (int32_t i = 0; i < (int32_t)bmp.height; i++)
			{
				uint8_t* pEx = src + (HGSize)i * (HGSize)(bmp.width * 4);
				uint8_t* pExEnd = pEx + bmp.width * 4;
				uint8_t* pDestEx = dest + (HGSize)i * (HGSize)destStep;

				while (pEx < pExEnd)
				{
					pDestEx[2] = pEx[0];
					pDestEx[1] = pEx[1];
					pDestEx[0] = pEx[2];

					pEx += 4;
					pDestEx += 3;
				}
			}
		}
		else if (HGBASE_IMGTYPE_BGRA == imgType)
		{
			//#pragma omp parallel for
			for (int32_t i = 0; i < (int32_t)bmp.height; i++)
			{
				uint8_t* pEx = src + (HGSize)i * (HGSize)(bmp.width * 4);
				uint8_t* pExEnd = pEx + bmp.width * 4;
				uint8_t* pDestEx = dest + (HGSize)i * (HGSize)destStep;

				while (pEx < pExEnd)
				{
					pDestEx[2] = pEx[0];
					pDestEx[1] = pEx[1];
					pDestEx[0] = pEx[2];
					pDestEx[3] = pEx[3];

					pEx += 4;
					pDestEx += 4;
				}
			}
		}
		else
		{
			assert(HGBASE_IMGTYPE_RGBA == imgType);

			//#pragma omp parallel for
			for (int32_t i = 0; i < (int32_t)bmp.height; i++)
			{
				uint8_t* pEx = src + (HGSize)i * (HGSize)(bmp.width * 4);
				uint8_t* pDestEx = dest + (HGSize)i * (HGSize)destStep;
				memcpy(pDestEx, pEx, bmp.width * 4);
			}
		}

		*image = image2;
	}

	bmp_finalise(&bmp);
	free(buffer);
	buffer = NULL;
	fclose(file);
	file = NULL;
	return HGBASE_ERR_OK;
}

HGResult HGAPI HGImgFmt_SaveBmpImage(HGImage image, const HGBmpSaveInfo* info, const HGChar* fileName)
{
	if (NULL == image || NULL == fileName)
	{
		return HGBASE_ERR_INVALIDARG;
	}

	if (NULL != info)
	{
		// 检查合法性
	}

	HGImageInfo imgInfo;
	HGBase_GetImageInfo(image, &imgInfo);

	uint32_t width = imgInfo.width;
	uint32_t height = imgInfo.height;
	uint32_t widthStep = imgInfo.widthStep;
	uint32_t type = imgInfo.type;
	uint32_t origin = imgInfo.origin;

	FILE* file = fopen(fileName, "wb");
	if (NULL == file)
	{
		return HGBASE_ERR_ACCESSDENIED;
	}

	uint8_t* data;
	HGBase_GetImageData(image, &data);

	uint8_t* buffer = (uint8_t*)malloc(widthStep * height);
	if (NULL == buffer)
	{
		fclose(file);
		file = NULL;
		return HGBASE_ERR_FAIL;
	}

	uint8_t fh[14];
	*(uint16_t*)fh = 0x4D42;
	*(uint16_t*)(fh + 6) = 0;
	*(uint16_t*)(fh + 8) = 0;

	uint8_t ih[40];
	*(uint32_t*)ih = 40;
	*(int32_t*)(ih + 4) = (int32_t)width;
	*(int32_t*)(ih + 8) = (int32_t)height;
	*(uint16_t*)(ih + 12) = 1;
	*(uint32_t*)(ih + 16) = 0;
	*(uint32_t*)(ih + 20) = (widthStep * height);
	*(int32_t*)(ih + 24) = 0;
	*(int32_t*)(ih + 28) = 0;
	*(uint32_t*)(ih + 32) = 0;
	*(uint32_t*)(ih + 36) = 0;

	HGUInt xDpi, yDpi;
	HGBase_GetImageDpi(image, &xDpi, &yDpi);

	*(int32_t*)(ih + 24) = (uint32_t)((double)xDpi * 39.3700787 + 0.5);
	*(int32_t*)(ih + 28) = (uint32_t)((double)yDpi * 39.3700787 + 0.5);

	if (NULL != info)
	{
		*(int32_t*)(ih + 24) = (int32_t)info->xPelsPerMeter;
		*(int32_t*)(ih + 28) = (int32_t)info->yPelsPerMeter;
	}

	if (HGBASE_IMGTYPE_GRAY == type)
	{
		*(uint32_t*)(fh + 2) = 54 + 4 * 256 + widthStep * height;
		*(uint32_t*)(fh + 10) = 54 + 4 * 256;
		*(uint16_t*)(ih + 14) = 8;

		uint32_t colorTable[256];
		//#pragma omp parallel for
		for (int32_t i = 0; i < 256; ++i)
		{
			uint32_t v = (i & 0x000000FF) | ((i << 8) & 0x0000FF00) | ((i << 16) & 0x00FF0000);
			colorTable[i] = v;
		}

		fwrite(fh, 14, 1, file);
		fwrite(ih, 40, 1, file);
		fwrite(colorTable, 4, 256, file);

		if (HGBASE_IMGORIGIN_BOTTOM == origin)
		{
			fwrite(data, 1, widthStep * height, file);
		}
		else
		{
			uint8_t* dataEx = data + (height - 1) * widthStep;
			while (dataEx >= data)
			{
				fwrite(dataEx, 1, widthStep, file);
				dataEx -= widthStep;
			}
		}
	}
	else if (HGBASE_IMGTYPE_RGB == type)
	{
		*(uint32_t*)(fh + 2) = 54 + widthStep * height;
		*(uint32_t*)(fh + 10) = 54;
		*(uint16_t*)(ih + 14) = 24;

		fwrite(fh, 14, 1, file);
		fwrite(ih, 40, 1, file);

		//#pragma omp parallel for
		for (int32_t i = 0; i < (int32_t)height; ++i)
		{
			uint8_t* pEx = data + (uintptr_t)i * (uintptr_t)widthStep;
			uint8_t* pExEnd = pEx + width * 3;
			uint8_t* pDestEx = buffer + (uintptr_t)i * (uintptr_t)widthStep;

			while (pEx < pExEnd)
			{
				pDestEx[0] = pEx[2];
				pDestEx[1] = pEx[1];
				pDestEx[2] = pEx[0];

				pEx += 3;
				pDestEx += 3;
			}
		}

		if (HGBASE_IMGORIGIN_BOTTOM == origin)
		{
			fwrite(buffer, 1, widthStep * height, file);
		}
		else
		{
			uint8_t* bufferEx = buffer + (height - 1) * widthStep;
			while (bufferEx >= buffer)
			{
				fwrite(bufferEx, 1, widthStep, file);
				bufferEx -= widthStep;
			}
		}
	}
	else if (HGBASE_IMGTYPE_BGR == type)
	{
		*(uint32_t*)(fh + 2) = 54 + widthStep * height;
		*(uint32_t*)(fh + 10) = 54;
		*(uint16_t*)(ih + 14) = 24;

		fwrite(fh, 14, 1, file);
		fwrite(ih, 40, 1, file);

		if (HGBASE_IMGORIGIN_BOTTOM == origin)
		{
			fwrite(data, 1, widthStep * height, file);
		}
		else
		{
			uint8_t* dataEx = data + (height - 1) * widthStep;
			while (dataEx >= data)
			{
				fwrite(dataEx, 1, widthStep, file);
				dataEx -= widthStep;
			}
		}
	}
	else if (HGBASE_IMGTYPE_BGRA == type)
	{
		*(uint32_t*)(fh + 2) = 54 + widthStep * height;
		*(uint32_t*)(fh + 10) = 54;
		*(uint16_t*)(ih + 14) = 32;

		fwrite(fh, 14, 1, file);
		fwrite(ih, 40, 1, file);

		if (HGBASE_IMGORIGIN_BOTTOM == origin)
		{
			fwrite(data, 1, widthStep * height, file);
		}
		else
		{
			uint8_t* dataEx = data + (height - 1) * widthStep;
			while (dataEx >= data)
			{
				fwrite(dataEx, 1, widthStep, file);
				dataEx -= widthStep;
			}
		}
	}
	else
	{
		assert(HGBASE_IMGTYPE_RGBA == type);

		*(uint32_t*)(fh + 2) = 54 + widthStep * height;
		*(uint32_t*)(fh + 10) = 54;
		*(uint16_t*)(ih + 14) = 32;

		fwrite(fh, 14, 1, file);
		fwrite(ih, 40, 1, file);

		//#pragma omp parallel for
		for (int32_t i = 0; i < (int32_t)height; ++i)
		{
			uint8_t* pEx = data + (uintptr_t)i * (uintptr_t)widthStep;
			uint8_t* pExEnd = pEx + width * 4;
			uint8_t* pDestEx = buffer + (uintptr_t)i * (uintptr_t)widthStep;

			while (pEx < pExEnd)
			{
				pDestEx[0] = pEx[2];
				pDestEx[1] = pEx[1];
				pDestEx[2] = pEx[0];
				pDestEx[3] = pEx[3];

				pEx += 4;
				pDestEx += 4;
			}
		}

		if (HGBASE_IMGORIGIN_BOTTOM == origin)
		{
			fwrite(buffer, 1, widthStep * height, file);
		}
		else
		{
			uint8_t* bufferEx = buffer + (height - 1) * widthStep;
			while (bufferEx >= buffer)
			{
				fwrite(bufferEx, 1, widthStep, file);
				bufferEx -= widthStep;
			}
		}
	}

	free(buffer);
	buffer = NULL;
	fclose(file);
	file = NULL;
	return HGBASE_ERR_OK;
}