#pragma once

/* Bitmap Header, 54 Bytes  */
static 
unsigned char BmpHeader[54] = 
{
	0x42, 0x4D, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x36, 0x00, 0x00, 0x00, 0x28, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1B, 0x01, 0x00, 0x00, 0x01, 0x00, 0x18, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x60, 0xCD, 0x04, 0x00, 0x23, 0x2E, 0x00, 0x00, 0x23, 0x2E, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};


void SetBitmapInfo(unsigned int size, int height, int width)
{
	for (int i = 0; i < 4; i++)
	{
		// size of image ( header + data )
		BmpHeader[2 + i] = size & 0xff;
		size >>= 8;

		// width of image
		BmpHeader[18 + i] = width & 0xff;
		width >>= 8;

		// height of image
		BmpHeader[22  + i] = height & 0xff;
		height >>= 8;
	}
}


/* BGR format */
unsigned char *Encoder(unsigned char *buf, int height, int width, int &size)
{
	unsigned char *bitmap = NULL;
	int rowSize = (24 * width + 31) / 32 * 4;
	
	// compute the size of total bytes of image
	size = rowSize * height + 54; // data size + header size
	bitmap = new unsigned char [ size ];
	
	// set the header info
	SetBitmapInfo(size, height, width);

	// fill the header area
	for (int i = 0; i < 54; i++)
	{
		bitmap[i] = BmpHeader[i];
	}
	
	// fill the data area
	for (int i = 0; i < height; i++)
	{
		// compute the offset of destination bitmap and source image
		int idx = height - 1 - i;
		int offsetDst = idx * rowSize + 54; // 54 means the header length
		int offsetSrc = i * width * 3;
		// fill data
		for (int j = 0; j < width * 3; j++)
		{
			bitmap[offsetDst + j] = buf[offsetSrc + j];
		}
		// fill 0x0, this part can be ignored
		for (int j = width * 3; j < rowSize; j++)
		{
			bitmap[offsetDst +j] = 0x0;
		}
	}

	return bitmap;
}


/* Save to file */
void Write(const char *fileName, unsigned char *buf, int &size)
{
	FILE *fp = fopen(fileName, "wb+");
	fwrite(buf, 1, size, fp);
	fclose(fp);
}