//pipelinedefine
#define H_URP

using HTraceWSGI.Scripts.Data.Private;
using UnityEngine;
using UnityEngine.Rendering;

namespace HTraceWSGI.Scripts.Passes.Shared
{
	public class VoxelizationFunctionsShared
	{
		//globals
		internal static readonly int g_OffsetAxisIndex      = Shader.PropertyToID("_OffsetAxisIndex");
		internal static readonly int g_AxisOffset           = Shader.PropertyToID("_AxisOffset");
		internal static readonly int g_CullingTrim          = Shader.PropertyToID("_CullingTrim");
		internal static readonly int g_OctantOffset         = Shader.PropertyToID("_OctantOffset");
		internal static readonly int g_CullingTrimAxis      = Shader.PropertyToID("_CullingTrimAxis");

		// Calculates offset data for voxelization
		internal static void CalculateOctantOffsets(CommandBuffer cmd)
		{
			Vector2 cullingTrim     = Vector2.zero;
			Vector2 cullingTrimAxis = Vector2.zero;
			Vector3 octantOffset    = Vector3.zero;
			Vector3 axisOffset      = Vector3.zero;

			Vector3 voxelResolutionSwizzled = new Vector3(HSettings.VoxelizationSettings.ExactData.Resolution.x, HSettings.VoxelizationSettings.ExactData.Resolution.z, HSettings.VoxelizationSettings.ExactData.Resolution.y);
			Vector3 axisOffsetSign  = VoxelizationRuntimeData.VoxelOctantCamera.transform.position - VoxelizationRuntimeData.VoxelCamera.transform.position;
			int offsetAxisIndex = (int)VoxelizationRuntimeData.OffsetAxisIndex > 2 ? (int)VoxelizationRuntimeData.OffsetAxisIndex - 3 : (int)VoxelizationRuntimeData.OffsetAxisIndex;
			int octantIndex = (int)VoxelizationRuntimeData.OctantIndex;

			if (offsetAxisIndex == 0) // X axis
			{
				axisOffset = axisOffsetSign.x > 0 ? new Vector3(voxelResolutionSwizzled.x / 2, 0, 0) : new Vector3(0, 0, 0);

				int cullingFarPlane = axisOffsetSign.x > 0
					? Mathf.RoundToInt(VoxelizationRuntimeData.CullingCamera.Camera.farClipPlane * HSettings.VoxelizationSettings.ExactData.VoxelsPerMeter)
					: Mathf.FloorToInt(VoxelizationRuntimeData.CullingCamera.Camera.farClipPlane * HSettings.VoxelizationSettings.ExactData.VoxelsPerMeter);

				cullingTrim = axisOffsetSign.x > 0 ? new Vector2((int)voxelResolutionSwizzled.x - cullingFarPlane, (int)voxelResolutionSwizzled.x) : new Vector2(0, cullingFarPlane);
				cullingTrimAxis = axisOffsetSign.x > 0 ? new Vector2(1,                                                0) : new Vector2(0,                              1);

				if (octantIndex == 1) octantOffset = new Vector3(0, voxelResolutionSwizzled.y / 2, 0);
				if (octantIndex == 2) octantOffset = new Vector3(0, voxelResolutionSwizzled.y / 2, voxelResolutionSwizzled.z / 2);
				if (octantIndex == 3) octantOffset = new Vector3(0, 0, 0);
				if (octantIndex == 4) octantOffset = new Vector3(0, 0, voxelResolutionSwizzled.z / 2);
			}

			if (offsetAxisIndex == 1) // Y axis
			{
				axisOffset = axisOffsetSign.y > 0 ? new Vector3(0, voxelResolutionSwizzled.y / 2, 0) : new Vector3(0, 0, 0);

				int cullingFarPlane = axisOffsetSign.y > 0
					? Mathf.RoundToInt(VoxelizationRuntimeData.CullingCamera.Camera.farClipPlane * HSettings.VoxelizationSettings.ExactData.VoxelsPerMeter)
					: Mathf.FloorToInt(VoxelizationRuntimeData.CullingCamera.Camera.farClipPlane * HSettings.VoxelizationSettings.ExactData.VoxelsPerMeter);

				cullingTrim = axisOffsetSign.y > 0 ? new Vector2((int)voxelResolutionSwizzled.y - cullingFarPlane, (int)voxelResolutionSwizzled.y) : new Vector2(0, cullingFarPlane);
				cullingTrimAxis = axisOffsetSign.y > 0 ? new Vector2(1, 0) : new Vector2(0, 1);

				if (octantIndex == 1) octantOffset = new Vector3(0, 0, 0);
				if (octantIndex == 2) octantOffset = new Vector3(0, 0, voxelResolutionSwizzled.z / 2);
				if (octantIndex == 3) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, 0);
				if (octantIndex == 4) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, voxelResolutionSwizzled.z / 2);
			}

			if (offsetAxisIndex == 2) // Z axis
			{
				axisOffset = axisOffsetSign.z > 0 ? new Vector3(0, 0, voxelResolutionSwizzled.z / 2) : new Vector3(0, 0, 0);

				int cullingFarPlane = axisOffsetSign.z > 0
					? Mathf.RoundToInt(VoxelizationRuntimeData.CullingCamera.Camera.farClipPlane * HSettings.VoxelizationSettings.ExactData.VoxelsPerMeter)
					: Mathf.FloorToInt(VoxelizationRuntimeData.CullingCamera.Camera.farClipPlane * HSettings.VoxelizationSettings.ExactData.VoxelsPerMeter);

				cullingTrim = axisOffsetSign.z > 0 ? new Vector2((int)voxelResolutionSwizzled.z - cullingFarPlane, (int)voxelResolutionSwizzled.z) : new Vector2(0, cullingFarPlane);
				cullingTrimAxis = axisOffsetSign.z > 0 ? new Vector2(1,                                                0) : new Vector2(0,                              1);

				if (octantIndex == 1) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, voxelResolutionSwizzled.y / 2, 0);
				if (octantIndex == 2) octantOffset = new Vector3(0, voxelResolutionSwizzled.y / 2, 0);
				if (octantIndex == 3) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, 0);
				if (octantIndex == 4) octantOffset = new Vector3(0, 0, 0);
			}
			
			cmd.SetGlobalInt(g_OffsetAxisIndex, offsetAxisIndex);
			cmd.SetGlobalVector(g_AxisOffset,      axisOffset);
			cmd.SetGlobalVector(g_CullingTrim,     cullingTrim);
			cmd.SetGlobalVector(g_OctantOffset,    octantOffset);
			cmd.SetGlobalVector(g_CullingTrimAxis, cullingTrimAxis);
		}

		// Calculates offset data for copying compute shader
		internal static Vector3 CalculateOctantOffsetsForCopyShader()
		{
			Vector3 octantOffset = Vector3.zero;

			Vector3 voxelResolutionSwizzled = new Vector3(HSettings.VoxelizationSettings.ExactData.Resolution.x, HSettings.VoxelizationSettings.ExactData.Resolution.z, HSettings.VoxelizationSettings.ExactData.Resolution.y);
			Vector3 axisOffsetSign = VoxelizationRuntimeData.VoxelOctantCamera.transform.position - VoxelizationRuntimeData.VoxelCamera.transform.position;
			int offsetAxisIndex = (int)VoxelizationRuntimeData.OffsetAxisIndex > 2 ? (int)VoxelizationRuntimeData.OffsetAxisIndex - 3 : (int)VoxelizationRuntimeData.OffsetAxisIndex;
			int octantIndex = (int)VoxelizationRuntimeData.OctantIndex;

			if (offsetAxisIndex == 0) // X axis
			{
				if (axisOffsetSign.x < 0)
				{
					if (octantIndex == 1) octantOffset = new Vector3(0, 0, 0);
					if (octantIndex == 2) octantOffset = new Vector3(0, 0, voxelResolutionSwizzled.z / 2);
					if (octantIndex == 3) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, voxelResolutionSwizzled.z / 2);
					if (octantIndex == 4) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, 0);
				}
				else
				{
					if (octantIndex == 1) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, 0);
					if (octantIndex == 2) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, voxelResolutionSwizzled.z / 2);
					if (octantIndex == 3) octantOffset = new Vector3(0, 0, 0);
					if (octantIndex == 4) octantOffset = new Vector3(0, 0, voxelResolutionSwizzled.z / 2);
				}
			}

			if (offsetAxisIndex == 1) // Y axis
			{
				if (octantIndex == 1) octantOffset = new Vector3(0, 0, 0);
				if (octantIndex == 2) octantOffset = new Vector3(0, 0, voxelResolutionSwizzled.z / 2);
				if (octantIndex == 3) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, 0);
				if (octantIndex == 4) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, voxelResolutionSwizzled.z / 2);
			}

			if (offsetAxisIndex == 2) // Z axis
			{
				if (axisOffsetSign.z < 0)
				{
					if (octantIndex == 1) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, 0);
					if (octantIndex == 2) octantOffset = new Vector3(0, 0, 0);
					if (octantIndex == 3) octantOffset = new Vector3(0, 0, voxelResolutionSwizzled.z / 2);
					if (octantIndex == 4) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, voxelResolutionSwizzled.z / 2);
				}
				else
				{
					if (octantIndex == 1) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, voxelResolutionSwizzled.z / 2);
					if (octantIndex == 2) octantOffset = new Vector3(0, 0, voxelResolutionSwizzled.z / 2);
					if (octantIndex == 3) octantOffset = new Vector3(0, 0, 0);
					if (octantIndex == 4) octantOffset = new Vector3(voxelResolutionSwizzled.x / 2, 0, 0);
				}
			}

			return octantOffset;
		}
	}
}