#include "stdafx.h"
#include "OutputDevice.h"
#include "DisplayMode.h"


OutputDevice::OutputDevice(IDXGIOutput* ar_Output_, ID3D10Device* ar_Device_)
	: m_Output(ar_Output_)
	, m_Device(ar_Device_)
	, m_HasEnumerated(false)
	, m_DesiredWidth(0)
	, m_DesiredHeight(0)
	, m_DesiredRefreshRate(0)
	, m_DesiredFormat(DataFormat::Unknown)
{
	if (m_Output != NULL)
	{
		m_Output->AddRef();
		m_Output->GetDesc(&m_OutputDesc);
	}
}


OutputDevice::~OutputDevice()
{
	for (uint32 i = 0; i < m_DisplayModes.size(); ++i)
		delete m_DisplayModes[i];

	if (m_Output != NULL)
		m_Output->Release();
	m_Output = NULL;
}


bool OutputDevice::TryEnumerate(uint32 argDesiredWidth, uint32 argDesiredHeight, uint32 argDesiredRefreshRate, DataFormat::Enumeration argDesiredFormat)
{
	if (m_HasEnumerated)
	{
		if (m_DesiredWidth == argDesiredWidth ||
			m_DesiredHeight == argDesiredHeight ||
			m_DesiredRefreshRate == argDesiredRefreshRate ||
			m_DesiredFormat == argDesiredFormat)
		{
			return true;
		}
		else
			m_HasEnumerated = false;
	}

	for (int formatIndex = (int)argDesiredFormat; formatIndex <= (argDesiredFormat == DataFormat::Unknown ? DXGI_FORMAT_B8G8R8X8_UNORM : (int)argDesiredFormat); ++formatIndex)
	{
		DXGI_FORMAT format = (DXGI_FORMAT)formatIndex;
		uint32 flags = DXGI_ENUM_MODES_SCALING;
		uint32 displayModeCount = 0;
		if (m_Output->GetDisplayModeList(format, flags, &displayModeCount, 0) == S_OK && displayModeCount > 0)
		{
			DXGI_MODE_DESC* descs = new DXGI_MODE_DESC[displayModeCount];
			if (m_Output->GetDisplayModeList(format, flags, &displayModeCount, descs) == S_OK)
			{
				for (uint32 i = 0; i < displayModeCount; ++i)
				{
					IDisplayMode* displayMode = new DisplayMode(descs[i]);
					bool keepDisplayMode = false;

					if ((argDesiredWidth == 0 || argDesiredWidth <= displayMode->get_Width()) &&
						(argDesiredHeight == 0 || argDesiredHeight <= displayMode->get_Height()) &&
						(argDesiredRefreshRate == 0 || argDesiredRefreshRate <= displayMode->get_RefreshRate()) &&
						(argDesiredFormat == DataFormat::Unknown || argDesiredFormat == displayMode->get_Format()))
					{
						if (m_Device != NULL)
						{
							uint32 supportBits = 0;
							m_Device->CheckFormatSupport((DXGI_FORMAT)format, &supportBits);
							if ((supportBits & D3D10_FORMAT_SUPPORT_DISPLAY) != 0)
								keepDisplayMode = true;
						}
						else
							keepDisplayMode = true;
					}

					if (keepDisplayMode)
						m_DisplayModes.push_back(displayMode);
					else
						delete displayMode;

				}
				delete [] descs;
			}
		}
	}

	m_DesiredWidth = argDesiredWidth;
	m_DesiredHeight = argDesiredHeight;
	m_DesiredRefreshRate = argDesiredRefreshRate;
	m_DesiredFormat = argDesiredFormat;

	m_HasEnumerated = !m_DisplayModes.empty();
	return m_HasEnumerated;
}


IDisplayMode* OutputDevice::FindBestDisplayMode(bool argAllowToEnumerate, uint32 argDesiredWidth, uint32 argDesiredHeight, uint32 argDesiredRefreshRate, DataFormat::Enumeration argDesiredFormat)
{
	if (argAllowToEnumerate && !this->TryEnumerate(argDesiredWidth, argDesiredHeight, argDesiredRefreshRate, argDesiredFormat))
		return NULL;

	if (!m_HasEnumerated)
		return NULL;

	return m_DisplayModes.back();
}