#include "VulkanDeviceManager.h"

#include <vector>

#include "Logger.h"
#include <map>

VulkanDeviceManager::VulkanDeviceManager()
{
}

VulkanDeviceManager::~VulkanDeviceManager()
{
	Cleanup();
}

VulkanDeviceManager::VulkanDeviceManager(VulkanDeviceManager&& Other) noexcept
{
}

VulkanDeviceManager& VulkanDeviceManager::operator=(VulkanDeviceManager&& Other) noexcept
{
	if (this != &Other)
	{
		Cleanup();
	}

	return *this;
}
void VulkanDeviceManager::Initialize(VkInstance Instance)
{
	if (IsInitialized())
	{
		return;
	}
}

void VulkanDeviceManager::Cleanup()
{
	if (!IsInitialized())
	{
		return;
	}
}

void VulkanDeviceManager::PickPhysicalDevice()
{
	uint32_t DeviceCount = 0;
	vkEnumeratePhysicalDevices(Instance, &DeviceCount, nullptr);

	if (DeviceCount == 0)
	{
		Log::Error("Failed to find GPU with Vulkan Support");
	}

	std::vector<VkPhysicalDevice> Devices(DeviceCount);
	vkEnumeratePhysicalDevices(Instance, &DeviceCount, Devices.data());

	std::multimap<int, VkPhysicalDevice> Candidates;

	for (const auto& Device : Devices)
	{
		int Score = RateDeviceSuitability(Device);
		Candidates.insert(std::make_pair(Score, Device));
	}

	if (Candidates.rbegin()->first > 0)
	{
		PhysicalDevice = Candidates.rbegin()->second;
	}
	else
	{
		Log::Error("Failed to find a suitable GPU");
	}
}

// bool VulkanDeviceManager::IsDeviceSuitable(VkPhysicalDevice Device)
//{
//	VkPhysicalDeviceProperties DeviceProperties;
//	vkGetPhysicalDeviceProperties(Device, &DeviceProperties);
//
//	VkPhysicalDeviceFeatures DeviceFeatures;
//	vkGetPhysicalDeviceFeatures(Device, &DeviceFeatures);
//
//	return DeviceProperties.deviceType == VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU && DeviceFeatures.geometryShader;
// }

int VulkanDeviceManager::RateDeviceSuitability(VkPhysicalDevice Device)
{
	VkPhysicalDeviceProperties DeviceProperties;
	vkGetPhysicalDeviceProperties(Device, &DeviceProperties);

	VkPhysicalDeviceFeatures DeviceFeatures;
	vkGetPhysicalDeviceFeatures(Device, &DeviceFeatures);

	int Score = 0;

	if (DeviceProperties.deviceType == VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU)
	{
		Score += 100;
	}

	Score += DeviceProperties.limits.maxImageDimension2D;

	if (!DeviceFeatures.geometryShader)
	{
		return 0;
	}

	return Score;
}