#include "HGPnm.h"
#include "../base/HGInc.h"
#include <vector>

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

	HGPnmLoadInfo info;
	HGResult ret = HGImgFmt_LoadPnmImage(fileName, &info, 0, 0, NULL);
	*isPnm = (HGBASE_ERR_OK == ret ? HGTRUE : HGFALSE);
	return HGBASE_ERR_OK;
}

static HGResult BnmLoadBinaryInfo(FILE* file, HGChar colorType, HGUInt *width, HGUInt *height, HGUInt *maxColor)
{
	assert(NULL != file && NULL != width && NULL != height && NULL != maxColor);

	bool getWidth = false;
	bool getHeight = false;
	bool getMaxColor = false;
	std::vector<char> buf;

	while (1)
	{
		HGByte c = 0;
		if (1 != fread(&c, 1, 1, file))
		{
			return HGBASE_ERR_INVALIDDATA;
		}

		if (c == '#' || c == '\n' || c == '\r' || c == '\t' || c == ' ')
		{
			if (!buf.empty())
			{
				buf.push_back(0);

				if (!getWidth)
				{
					*width = atoi(&buf[0]);
					if (*width == 0)
						return HGBASE_ERR_INVALIDDATA;
					getWidth = true;
				}
				else if (!getHeight)
				{
					*height = atoi(&buf[0]);
					if (*height == 0)
						return HGBASE_ERR_INVALIDDATA;
					getHeight = true;
				}
				else if (!getMaxColor)
				{
					*maxColor = atoi(&buf[0]);
					if (*maxColor == 0)
						return HGBASE_ERR_INVALIDDATA;
					getMaxColor = true;
				}

				buf.clear();
			}

			if (c == '#')
			{
				while (c != '\n')
				{
					if (1 != fread(&c, 1, 1, file))
					{
						return HGBASE_ERR_INVALIDDATA;
					}
				}
			}
		}
		else if (c >= '0' && c <= '9')
		{
			buf.push_back(c);
		}
		else
		{
			return HGBASE_ERR_INVALIDDATA;
		}

		if ('5' == colorType || '6' == colorType)
		{
			if (getMaxColor)
			{
				break;
			}
		}
		else
		{
			if (getHeight)
			{
				break;
			}
		}
	}

	return HGBASE_ERR_OK;
}

static HGResult BnmLoadBinaryImage(FILE* file, HGChar colorType, HGPnmLoadInfo* info, HGUInt imgType, HGUInt imgOrigin, HGImage* image)
{
	HGUInt width, height, maxColor;
	HGResult ret = BnmLoadBinaryInfo(file , colorType, &width, &height, &maxColor);
	if (HGBASE_ERR_OK != ret)
	{
		return ret;
	}

	if (NULL != info)
	{
		info->width = width;
		info->height = height;

		if ('4' == colorType)
			info->type = HGIMGFMT_PNMTYPE_BINARY_BINARY;
		else if('5' == colorType)
			info->type = HGIMGFMT_PNMTYPE_GRAY_BINARY;
		else
			info->type = HGIMGFMT_PNMTYPE_RGB_BINARY;
	}

	if (NULL != image)
	{
		if (imgType == 0)
		{
			if ('4' == colorType)
				imgType = HGBASE_IMGTYPE_BINARY;
			else if ('5' == colorType)
				imgType = HGBASE_IMGTYPE_GRAY;
			else
				imgType = HGBASE_IMGTYPE_RGB;
		}

		if (imgOrigin == 0)
		{
			imgOrigin = HGBASE_IMGORIGIN_TOP;
		}

		HGImage image2 = NULL;

		if (colorType == '4')
			ret = HGBase_CreateImage(width, height, HGBASE_IMGTYPE_BINARY, HGBASE_IMGORIGIN_TOP, &image2);
		else if (colorType == '5')
			ret = HGBase_CreateImage(width, height, HGBASE_IMGTYPE_GRAY, HGBASE_IMGORIGIN_TOP, &image2);
		else
			ret = HGBase_CreateImage(width, height, HGBASE_IMGTYPE_RGB, HGBASE_IMGORIGIN_TOP, &image2);

		if (HGBASE_ERR_OK != ret)
		{
			return ret;
		}

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

		if ('4' == colorType)
		{
			for (HGUInt i = 0; i < height; ++i)
			{
				HGUInt lineSize = ((width + 7) & ~7) >> 3;
				if (lineSize != fread(data + i * imgInfo.widthStep, 1, lineSize, file))
				{
					HGBase_DestroyImage(image2);
					return HGBASE_ERR_INVALIDDATA;
				}
			}

			if (HGBASE_IMGTYPE_BINARY == imgType && HGBASE_IMGORIGIN_TOP == imgOrigin)
			{
				*image = image2;
			}
			else
			{
				ret = HGBase_CloneImage(image2, imgType, imgOrigin, image);
				HGBase_DestroyImage(image2);

				if (HGBASE_ERR_OK != ret)
				{
					return ret;
				}
			}
				
		}
		else if ('5' == colorType)
		{
			for (HGUInt i = 0; i < height; ++i)
			{
				if (width != fread(data + i * imgInfo.widthStep, 1, width, file))
				{
					HGBase_DestroyImage(image2);
					return HGBASE_ERR_INVALIDDATA;
				}
			}

			if (HGBASE_IMGTYPE_GRAY == imgType && HGBASE_IMGORIGIN_TOP == imgOrigin)
			{
				*image = image2;
			}
			else
			{
				ret = HGBase_CloneImage(image2, imgType, imgOrigin, image);
				HGBase_DestroyImage(image2);

				if (HGBASE_ERR_OK != ret)
				{
					return ret;
				}
			}
		}
		else
		{
			for (HGUInt i = 0; i < height; ++i)
			{
				if (width * 3 != fread(data + i * imgInfo.widthStep, 1, width * 3, file))
				{
					HGBase_DestroyImage(image2);
					return HGBASE_ERR_INVALIDDATA;
				}
			}

			if (HGBASE_IMGTYPE_RGB == imgType && HGBASE_IMGORIGIN_TOP == imgOrigin)
			{
				*image = image2;
			}
			else
			{
				ret = HGBase_CloneImage(image2, imgType, imgOrigin, image);
				HGBase_DestroyImage(image2);

				if (HGBASE_ERR_OK != ret)
				{
					return ret;
				}
			}
		}

		if ('4' == colorType)
		{
			HGBase_ReverseImage(image2, image2);
		}
	}

	return HGBASE_ERR_OK;
}

HGResult HGAPI HGImgFmt_LoadPnmImage(const HGChar* fileName, HGPnmLoadInfo* 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_BINARY != imgType && HGBASE_IMGTYPE_GRAY != imgType
			&& HGBASE_IMGTYPE_BGR != imgType && HGBASE_IMGTYPE_RGB != imgType
			&& HGBASE_IMGTYPE_BGRA != imgType && HGBASE_IMGTYPE_RGBA != imgType)
		{
			return HGBASE_ERR_INVALIDARG;
		}

		if (0 != imgOrigin && HGBASE_IMGORIGIN_TOP != imgOrigin && HGBASE_IMGORIGIN_BOTTOM != imgOrigin)
		{
			return HGBASE_ERR_INVALIDARG;
		}
	}

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

	HGByte magicKey[2] = {0};
	if (2 != fread(magicKey, 1, 2, file))
	{
		return HGBASE_ERR_INVALIDDATA;
	}

	HGResult ret = HGBASE_ERR_INVALIDDATA;
	if (magicKey[0] == 'P' && (magicKey[1] == '4' || magicKey[1] == '5' || magicKey[1] == '6'))
	{
		HGChar colorType = magicKey[1];
		ret = BnmLoadBinaryImage(file, colorType, info, imgType, imgOrigin, image);
	}

	fclose(file);
	return ret;
}

static HGResult BnmSaveImage(HGImage image, const HGChar* fileName, HGUInt type)
{
	HGImageInfo imgInfo;
	HGBase_GetImageInfo(image, &imgInfo);

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

	HGByte* data = NULL;
	HGBase_GetImageData(image, &data);

	char magicKey[4] = {0};
	if (HGIMGFMT_PNMTYPE_BINARY_BINARY == type)
	{
		strcpy(magicKey, "P4\n");
	}
	else if (HGIMGFMT_PNMTYPE_GRAY_BINARY == type)
	{
		strcpy(magicKey, "P5\n");
	}
	else if (HGIMGFMT_PNMTYPE_RGB_BINARY == type)
	{
		strcpy(magicKey, "P6\n");
	}

	fwrite(magicKey, 1, strlen(magicKey), file);

	char width[20], height[20];
	sprintf(width, "%u\n", imgInfo.width);
	sprintf(height, "%u\n", imgInfo.height);
	fwrite(width, 1, strlen(width), file);
	fwrite(height, 1, strlen(height), file);

	if (HGIMGFMT_PNMTYPE_GRAY_BINARY == type || HGIMGFMT_PNMTYPE_RGB_BINARY == type)
	{
		char maxColor[] = "255\n";
		fwrite(maxColor, 1, strlen(maxColor), file);
	}

	HGByte* p = data;
	HGInt step = (HGInt)imgInfo.widthStep;
	if (HGBASE_IMGORIGIN_BOTTOM == imgInfo.origin)
	{
		p = data + (imgInfo.height - 1) * imgInfo.widthStep;
		step = -(HGInt)imgInfo.widthStep;
	}

	if (imgInfo.type == HGBASE_IMGTYPE_BINARY)
	{
		HGUInt lineSize = ((imgInfo.width + 7) & ~7) >> 3;
		HGByte* buf = (HGByte*)malloc(lineSize);
		assert(NULL != buf);

		for (HGUInt i = 0; i < imgInfo.height; ++i)
		{
			uint8_t* pEx = p + (HGSize)i * (HGSize)step;
			for (HGUInt j = 0; j < lineSize; ++j)
			{
				buf[j] = ~pEx[j];	//黑白反色
			}

			fwrite(buf, 1, lineSize, file);
		}

		free(buf);
	}
	else if (imgInfo.type == HGBASE_IMGTYPE_GRAY)
	{
		for (HGUInt i = 0; i < imgInfo.height; ++i)
		{
			uint8_t* pEx = p + (HGSize)i * (HGSize)step;
			fwrite(pEx, 1, imgInfo.width, file);
		}
	}
	else
	{
		for (HGUInt i = 0; i < imgInfo.height; ++i)
		{
			uint8_t* pEx = p + (HGSize)i * (HGSize)step;
			fwrite(pEx, 1, imgInfo.width * 3, file);
		}
	}

	fclose(file);
	return HGBASE_ERR_OK;
}

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

	if (NULL != info)
	{
		if (info->type < HGIMGFMT_PNMTYPE_BINARY_ASCII || info->type > HGIMGFMT_PNMTYPE_RGB_BINARY)
		{
			return HGBASE_ERR_INVALIDARG;
		}
	}

	HGImageInfo imgInfo;
	HGBase_GetImageInfo(image, &imgInfo);
	if (imgInfo.type == HGBASE_IMGTYPE_BGR || imgInfo.type == HGBASE_IMGTYPE_RGBA || imgInfo.type == HGBASE_IMGTYPE_BGRA)
	{
		HGUInt imgType = HGBASE_IMGTYPE_RGB;
		HGUInt pnmType = HGIMGFMT_PNMTYPE_RGB_BINARY;

		if (NULL != info)
		{
			pnmType = info->type;
			if (info->type == HGIMGFMT_PNMTYPE_BINARY_ASCII || info->type == HGIMGFMT_PNMTYPE_BINARY_BINARY)
				imgType = HGBASE_IMGTYPE_BINARY;
			else if (info->type == HGIMGFMT_PNMTYPE_GRAY_ASCII || info->type == HGIMGFMT_PNMTYPE_GRAY_BINARY)
				imgType = HGBASE_IMGTYPE_GRAY;
		}

		HGImage image2 = NULL;
		HGResult ret = HGBase_CloneImage(image, imgType, HGBASE_IMGORIGIN_TOP, &image2);
		if (ret != HGBASE_ERR_OK)
		{
			return ret;
		}

		ret = BnmSaveImage(image2, fileName, pnmType);
		HGBase_DestroyImage(image2);
		return ret;
	}

	HGImage image2 = NULL;
	HGUInt pnmType = HGIMGFMT_PNMTYPE_RGB_BINARY;
	if (HGBASE_IMGTYPE_GRAY == imgInfo.type)
		pnmType = HGIMGFMT_PNMTYPE_GRAY_BINARY;
	else if (HGBASE_IMGTYPE_BINARY == imgInfo.type)
		pnmType = HGIMGFMT_PNMTYPE_BINARY_BINARY;

	if (NULL != info)
	{
		HGUInt imgType = imgInfo.type;
		pnmType = info->type;

		if (info->type == HGIMGFMT_PNMTYPE_BINARY_ASCII || info->type == HGIMGFMT_PNMTYPE_BINARY_BINARY)
			imgType = HGBASE_IMGTYPE_BINARY;
		else if (info->type == HGIMGFMT_PNMTYPE_GRAY_ASCII || info->type == HGIMGFMT_PNMTYPE_GRAY_BINARY)
			imgType = HGBASE_IMGTYPE_GRAY;
		else if (info->type == HGIMGFMT_PNMTYPE_RGB_ASCII || info->type == HGIMGFMT_PNMTYPE_RGB_BINARY)
			imgType = HGBASE_IMGTYPE_RGB;

		if (imgInfo.type != imgType)
		{
			HGResult ret = HGBase_CloneImage(image, imgType, HGBASE_IMGORIGIN_TOP, &image2);
			if (ret != HGBASE_ERR_OK)
			{
				return ret;
			}
		}
	}

	if (NULL != image2)
	{
		HGResult ret = BnmSaveImage(image2, fileName, pnmType);
		HGBase_DestroyImage(image2);
		return ret;
	}

	return BnmSaveImage(image, fileName, pnmType);
}