#include "asset/dvc_image.h"
#include "math/dvc_math_util.h"
#include "device/dvc_device.h"
#include "device/dvc_buffer.h"

DV_CORE_BEGIN_NAMESPACE

Image::Image(int32_t id)
	: m_id(id)
{
}

Image::~Image()
{
}

void Image::clear()
{
	m_width = 0;
	m_height = 0;
	m_pixelFormat = PF_UNKNOWN;
	m_pixelByteSize = 0;
	m_pixelBuffer = nullptr;
}

fVector4 Image::getPixel(int32_t u, int32_t v) const
{
	if(u<0 || u>=m_width || v<0 || v>=m_height)
	{
		return fVector4::ZERO;
	}

	const uint8_t* p = (const uint8_t*)(m_pixelBuffer->ptr(0)) + (v * m_width + u) * m_pixelByteSize;
	switch (m_pixelFormat)
	{
		case PF_UINT8_ALPHA:
			return fVector4(0, 0, 0, p[0] / 255.0f);
		case PF_UINT8_RGB:
			return fVector4(p[0] / 255.0f, p[1] / 255.0f, p[2] / 255.0f, 1.0f);
		case PF_UINT8_RGBA:
			return fVector4(p[0] / 255.0f, p[1] / 255.0f, p[2] / 255.0f, p[3] / 255.0f);
		case PF_FLOAT32_ALPHA:
			return fVector4(0, 0, 0, *((const float*)p));
		case PF_FLOAT32_RGB:
		{
			const float* fp = (const float*)p;
			return fVector4(fp[0], fp[1], fp[2], 1.0f);
		}
		case PF_FLOAT32_RGBA:
		{
			const float* fp = (const float*)p;
			return fVector4(fp[0], fp[1], fp[2], fp[3]);
		}
	default:
		return fVector4::ZERO;
	}
}

bool Image::initWithPixelData(Device& device, int32_t width, int32_t height, 
	PixelFormat pixelFormat, const uint8_t* data, size_t dataSize)
{
	clear();

	size_t pixelByteSize = MathUtil::PixelSize(pixelFormat);
	if (dataSize != pixelByteSize*width*height)
	{
		return false;
	}

	m_width = width;
	m_height = height;
	m_pixelFormat = pixelFormat;
	m_pixelByteSize = pixelByteSize;
	m_pixelBuffer = device.newDeviceBuffer(dataSize);
	memcpy(m_pixelBuffer->ptr(0), data, dataSize);
	return true;
}

DV_CORE_END_NAMESPACE