/*
 * C# / XNA  port of Bullet (c) 2011 Mark Neale <[email protected]>
 *
 * Bullet Continuous Collision Detection and Physics Library
 * Copyright (c) 2003-2008 Erwin Coumans  http://www.bulletphysics.com/
 *
 * This software is provided 'as-is', without any express or implied warranty.
 * In no event will the authors be held liable for any damages arising from
 * the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
 *    appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 */
// Adapted from BulletXNA 73b2e1b9: namespace isolation, no XNA rendering, one type per file.
#nullable disable
#pragma warning disable CS1591, CS0168, CS0219, CS0414, CS0660, CS0661, CS0659, CS0693, CS8981, CS0108, CS0114
using HumanoidRetargeter.Core.Formats.Mmd.Bullet.LinearMath;

namespace HumanoidRetargeter.Core.Formats.Mmd.Bullet.BulletCollision;

internal class Convex2dConvex2dAlgorithm : ActivatingCollisionAlgorithm
{
	public Convex2dConvex2dAlgorithm(PersistentManifold mf, CollisionAlgorithmConstructionInfo ci, CollisionObject body0, CollisionObject body1, ISimplexSolverInterface simplexSolver, IConvexPenetrationDepthSolver pdSolver, int numPerturbationIterations, int minimumPointsPerturbationThreshold) : base(ci, body0, body1)
	{
		m_simplexSolver = simplexSolver;
		m_pdSolver = pdSolver;
		m_ownManifold = false;
		m_manifoldPtr = mf;
		m_lowLevelOfDetail = false;
		m_numPerturbationIterations = numPerturbationIterations;
		m_minimumPointsPerturbationThreshold = minimumPointsPerturbationThreshold;
	}

	public override void Cleanup()
	{
		if (m_ownManifold)
		{
			if (m_manifoldPtr != null)
			{
				m_dispatcher.ReleaseManifold(m_manifoldPtr);
				m_manifoldPtr = null;
			}

			m_ownManifold = false;
		}
	}

	public override void ProcessCollision(CollisionObject body0, CollisionObject body1, DispatcherInfo dispatchInfo, ManifoldResult resultOut)
	{
		if (m_manifoldPtr == null)
		{
			//swapped?
			m_manifoldPtr = m_dispatcher.GetNewManifold(body0, body1);
			m_ownManifold = true;
		}

		resultOut.SetPersistentManifold(m_manifoldPtr);
		//comment-out next line to test multi-contact generation
		//resultOut.getPersistentManifold().clearManifold();
		ConvexShape min0 = body0.GetCollisionShape() as ConvexShape;
		ConvexShape min1 = body1.GetCollisionShape() as ConvexShape;
		IndexedVector3 normalOnB = IndexedVector3.Zero;
		IndexedVector3 pointOnBWorld = IndexedVector3.Zero;
		{
			ClosestPointInput input = ClosestPointInput.Default();
			using (GjkPairDetector gjkPairDetector = BulletGlobals.GjkPairDetectorPool.Get())
			{
				gjkPairDetector.Initialize(min0, min1, m_simplexSolver, m_pdSolver);
				//TODO: if (dispatchInfo.m_useContinuous)
				gjkPairDetector.SetMinkowskiA(min0);
				gjkPairDetector.SetMinkowskiB(min1);
				{
					input.m_maximumDistanceSquared = min0.GetMargin() + min1.GetMargin() + m_manifoldPtr.GetContactBreakingThreshold();
					input.m_maximumDistanceSquared *= input.m_maximumDistanceSquared;
				}

				input.m_transformA = body0.GetWorldTransform();
				input.m_transformB = body1.GetWorldTransform();
				gjkPairDetector.GetClosestPoints(ref input, resultOut, dispatchInfo.getDebugDraw(), false);
			}
		//BulletGlobals.GjkPairDetectorPool.Free(gjkPairDetector);
		//btVector3 v0,v1;
		//btVector3 sepNormalWorldSpace;
		}

		if (m_ownManifold)
		{
			resultOut.RefreshContactPoints();
		}
	}

	public override float CalculateTimeOfImpact(CollisionObject body0, CollisionObject body1, DispatcherInfo dispatchInfo, ManifoldResult resultOut)
	{
		float resultFraction = 1.0f;
		float squareMot0 = (body0.GetInterpolationWorldTransform()._origin - body0.GetWorldTransform()._origin).LengthSquared();
		float squareMot1 = (body1.GetInterpolationWorldTransform()._origin - body1.GetWorldTransform()._origin).LengthSquared();
		if (squareMot0 < body0.GetCcdSquareMotionThreshold() && squareMot1 < body1.GetCcdSquareMotionThreshold())
		{
			return resultFraction;
		}

		//An adhoc way of testing the Continuous Collision Detection algorithms
		//One object is approximated as a sphere, to simplify things
		//Starting in penetration should report no time of impact
		//For proper CCD, better accuracy and handling of 'allowed' penetration should be added
		//also the mainloop of the physics should have a kind of toi queue (something like Brian Mirtich's application of Timewarp for Rigidbodies)
		{
			ConvexShape convex0 = body0.GetCollisionShape() as ConvexShape;
			SphereShape sphere1 = BulletGlobals.SphereShapePool.Get();
			sphere1.Initialize(body1.GetCcdSweptSphereRadius()); //todo: allow non-zero sphere sizes, for better approximation
			CastResult result = BulletGlobals.CastResultPool.Get();
			VoronoiSimplexSolver voronoiSimplex = BulletGlobals.VoronoiSimplexSolverPool.Get();
			//SubsimplexConvexCast ccd0(&sphere,min0,&voronoiSimplex);
			using (GjkConvexCast ccd1 = BulletGlobals.GjkConvexCastPool.Get())
			{
				ccd1.Initialize(convex0, sphere1, voronoiSimplex);
				//ContinuousConvexCollision ccd(min0,min1,&voronoiSimplex,0);
				if (ccd1.CalcTimeOfImpact(body0.GetWorldTransform(), body0.GetInterpolationWorldTransform(), body1.GetWorldTransform(), body1.GetInterpolationWorldTransform(), result))
				{
					//store result.m_fraction in both bodies
					if (body0.GetHitFraction() > result.m_fraction)
					{
						body0.SetHitFraction(result.m_fraction);
					}

					if (body1.GetHitFraction() > result.m_fraction)
					{
						body1.SetHitFraction(result.m_fraction);
					}

					if (resultFraction > result.m_fraction)
					{
						resultFraction = result.m_fraction;
					}
				}

				BulletGlobals.VoronoiSimplexSolverPool.Free(voronoiSimplex);
				BulletGlobals.SphereShapePool.Free(sphere1);
				result.Cleanup();
			}
		}

		{
			ConvexShape convex1 = body1.GetCollisionShape() as ConvexShape;
			SphereShape sphere0 = BulletGlobals.SphereShapePool.Get();
			sphere0.Initialize(body0.GetCcdSweptSphereRadius()); //todo: allow non-zero sphere sizes, for better approximation
			CastResult result = BulletGlobals.CastResultPool.Get();
			VoronoiSimplexSolver voronoiSimplex = BulletGlobals.VoronoiSimplexSolverPool.Get();
			//SubsimplexConvexCast ccd0(&sphere,min0,&voronoiSimplex);
			using (GjkConvexCast ccd1 = BulletGlobals.GjkConvexCastPool.Get())
			{
				ccd1.Initialize(sphere0, convex1, voronoiSimplex);
				//ContinuousConvexCollision ccd(min0,min1,&voronoiSimplex,0);
				if (ccd1.CalcTimeOfImpact(body0.GetWorldTransform(), body0.GetInterpolationWorldTransform(), body1.GetWorldTransform(), body1.GetInterpolationWorldTransform(), result))
				{
					//store result.m_fraction in both bodies
					if (body0.GetHitFraction() > result.m_fraction)
					{
						body0.SetHitFraction(result.m_fraction);
					}

					if (body1.GetHitFraction() > result.m_fraction)
					{
						body1.SetHitFraction(result.m_fraction);
					}

					if (resultFraction > result.m_fraction)
					{
						resultFraction = result.m_fraction;
					}
				}

				BulletGlobals.VoronoiSimplexSolverPool.Free(voronoiSimplex);
				BulletGlobals.SphereShapePool.Free(sphere0);
				result.Cleanup();
			}
		}

		return resultFraction;
	}

	public override void GetAllContactManifolds(PersistentManifoldArray manifoldArray)
	{
		if (m_manifoldPtr != null && m_ownManifold)
		{
			manifoldArray.Add(m_manifoldPtr);
		}
	}

	public void SetLowLevelOfDetail(bool useLowLevel)
	{
		m_lowLevelOfDetail = useLowLevel;
	}

	public PersistentManifold GetManifold()
	{
		return m_manifoldPtr;
	}

	private ISimplexSolverInterface m_simplexSolver;
	private IConvexPenetrationDepthSolver m_pdSolver;
	private bool m_ownManifold;
	private PersistentManifold m_manifoldPtr;
	private bool m_lowLevelOfDetail;
	private int m_numPerturbationIterations;
	private int m_minimumPointsPerturbationThreshold;
}