/*
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/.
 */

#pragma once

#include "Math/Math.hpp"
#include "Math/Timestamp.hpp"
#include "Math/Pose.hpp"
#include "Math/CameraIntrinsic.hpp"
#include "ArDepthFormat.hpp"
#include "ArTrackingState.hpp"
#include "ArFrameMetadata.hpp"
#include <functional>
#include <filesystem>
#include <memory>

namespace OpenVulkano::Scene
{
	class Texture;
}

namespace OpenVulkano::AR
{
	class ArSession;

	class ArImage
	{
	public:
		void* data;
		Math::Vector2ui resolution;
		uint32_t numChannels = 1;
		uint32_t rowPadding = 0;
		
		operator bool() const { return data; }
	};

	class ArImagePlanar
	{
	public:
		enum class Format { NV12, NV21, RGB, BGR };

		ArImage luminescenceOrColor;
		ArImage uv;

		Math::CameraIntrinsic intrinsic;
		Format format = Format::NV12;

		[[nodiscard]] Math::Vector4uc Sample(float nx, float ny, bool asRgb = true) const
		{
			return Sample(static_cast<uint32_t>(nx * luminescenceOrColor.resolution.x), static_cast<uint32_t>(ny * luminescenceOrColor.resolution.y), asRgb);
		}

		[[nodiscard]] Math::Vector4uc Sample(uint32_t x, uint32_t y, bool asRgb = true) const
		{
			const uint8_t* lumColBuffer = static_cast<const uint8_t*>(luminescenceOrColor.data);
			if (format == Format::BGR)
			{
				size_t idx = (y * luminescenceOrColor.resolution.x + x) * luminescenceOrColor.numChannels;
				return { lumColBuffer[idx + 2], lumColBuffer[idx + 1], lumColBuffer[idx], 255 };
			}
			else if (format == Format::RGB)
			{
				size_t idx = (y * luminescenceOrColor.resolution.x + x) * luminescenceOrColor.numChannels;
				return { lumColBuffer[idx], lumColBuffer[idx + 1], lumColBuffer[idx + 2], 255 };
			}

			int iUV = ((y / 2) * (uv.resolution.x + uv.rowPadding / 2) + x / 2) * 2;

			Math::Vector4uc sample(
					lumColBuffer[y * (luminescenceOrColor.resolution.x + luminescenceOrColor.rowPadding)  + x],
					static_cast<const uint8_t*>(uv.data)[iUV],
					static_cast<const uint8_t*>(uv.data)[iUV+1],
					255);

			if (asRgb)
			{
				Math::Vector4f c(sample);
				Math::Matrix4f conversionMatrix(
						Math::Vector4f(+1.0000f, +1.0000f, +1.0000f, +0.0000f),
						Math::Vector4f(+0.0000f, -0.3441f, +1.7720f, +0.0000f),
						Math::Vector4f(+1.4020f, -0.7141f, +0.0000f, +0.0000f),
						Math::Vector4f(-0.7010f, +0.5291f, -0.8860f, +1.0000f)
				);
				sample = Math::Utils::clamp(conversionMatrix * c, 0.0f, 255.0f);
			}

			return sample;
		}
	};

	class ArDepthImage
	{
	public:
		ArImage depth;
		ArImage confidence;
		ArDepthFormat format;
		Math::CameraIntrinsic intrinsic;
		
		operator bool() const { return depth; }
	};

	class ArFrame : public std::enable_shared_from_this<ArFrame>
	{
		std::shared_ptr<ArSession> m_session;
		size_t m_frameId;
		Scene::Texture* m_texture = nullptr;
		bool m_saved = false;
		bool m_highRes = false;

	protected:
		ArFrameMetadata frameMetadata;

		ArFrame(const std::shared_ptr<ArSession>& session, size_t frameId) : m_session(session), m_frameId(frameId)
		{}

	public:
		virtual ~ArFrame();

		[[nodiscard]] size_t GetFrameId() const { return m_frameId; }

		[[nodiscard]] const ArFrameMetadata& GetFrameMetadata() const { return frameMetadata; }

		[[nodiscard]] const std::shared_ptr<ArSession>& GetArSession() const { return m_session; }

		[[nodiscard]] ArTrackingState GetTrackingState() const { return frameMetadata.trackingState; };

		[[nodiscard]] virtual Math::PoseF GetPose() const { return Math::PoseF(frameMetadata.transformation); };

		[[nodiscard]] virtual Math::Vector3f GetEulerAngle() const {
			return {
					asin(-frameMetadata.transformation[2][1]),
					atan2(frameMetadata.transformation[2][0], frameMetadata.transformation[2][2]),
					atan2(frameMetadata.transformation[0][1], frameMetadata.transformation[1][1])
			};
		}

		[[nodiscard]] virtual const Math::Vector3f_SIMD& GetPosition() const
		{
			return reinterpret_cast<const Math::Vector3f_SIMD&>(frameMetadata.transformation[3]);
		}

		[[nodiscard]] Math::Timestamp GetTimestamp() const { return frameMetadata.timestamp; };

		[[nodiscard]] Math::Timestamp GetTimestampDepth() const { return frameMetadata.timestampDepth; };

		[[nodiscard]] virtual ArImagePlanar GetCameraImage() = 0;

		[[nodiscard]] virtual ArDepthImage GetDepthImage() = 0;

		[[nodiscard]] const Math::Matrix4f& GetCameraTransformation() const { return frameMetadata.transformation; };

		[[nodiscard]] virtual Math::Matrix4f GetCameraViewForCurrentDeviceOrientation() = 0;

		[[nodiscard]] const Math::Matrix4f& GetCameraProjection() const { return frameMetadata.projection; }
		
		[[nodiscard]] const Math::CameraIntrinsicWithResolution& GetCameraIntrinsic() const { return frameMetadata.intrinsic; }

		[[nodiscard]] virtual Math::Matrix4f GetCameraProjection(Math::Vector2f viewportSize, float near = 0.25f, float far = 250.0f) = 0;

		[[nodiscard]] float GetConfidenceNormalisationFactor() const;

		[[nodiscard]] float GetColorTemperature() const { return frameMetadata.lightColorTemp; };

		[[nodiscard]] float GetLightIntensity() const { return frameMetadata.lightIntensity; };

		[[nodiscard]] float GetExposureTime() const { return frameMetadata.exposureTime; };

		[[nodiscard]] float GetExposureOffset() const { return frameMetadata.exposureOffset; };
		
		[[nodiscard]] float GetFocalLength() const { return frameMetadata.focalLength; }
		
		[[nodiscard]] float GetFNumber() const { return frameMetadata.fNumber; }

		[[nodiscard]] bool IsSaved() const { return m_saved; };

		[[nodiscard]] const Scene::Texture* GetImageTexture();

		[[nodiscard]] virtual std::string GetLensModel() const { return ""; }

		void Save();

		void SaveToFile(const std::filesystem::path& path, bool downsample = false, bool includeAux = true);

		void SetSaved() { m_saved = true; }

		void MarkHighRes() { m_highRes = true; }

		[[nodiscard]] bool IsHighResolution() const { return m_highRes; }

		/**
		 * Uses the platforms native jpeg writer to produce a jpeg representation of the camera image.
		 * This might not be implemented
		 * @param handler Function to be called once the image has been encoded
		 * @return true if image was encoded, false if not or unavailable
		 */
		virtual bool GetCameraImageAsJpeg(const std::function<void(const char*, size_t)>& handler) { return false; };
	};
}