using System.Collections;

namespace LibMMD.Unity3D.Physics
{
    internal sealed class NoneMmdPhysicsBackend : IMmdPhysicsBackend
    {
        public IEnumerator Build(MmdPhysicsBuildContext context) { yield break; }
        public bool CalculateMorphBeforePhysics => false;
        public bool[] TransformSkipMask => null;
        public void Reset() { }
        public void Step(float deltaTime, float physicsFps, int maxSubSteps) { }
        public void Dispose() { }
    }

    internal sealed class UnityMmdPhysicsBackend : IMmdPhysicsBackend
    {
        private UnityEngine.Rigidbody[] _rigidbodies;
        public bool CalculateMorphBeforePhysics => false;
        public bool[] TransformSkipMask { get; private set; }

        public IEnumerator Build(MmdPhysicsBuildContext context)
        {
            var builder = new MmdGameObjectPhysicsBuilder(context.Owner, context.Model,
                context.Bones, context.BoneRoot.gameObject, (System.Collections.Generic.List<System.Collections.Generic.List<int>>)context.PartIndexes);
            TransformSkipMask = builder.BuildUnityPhysicsComponents();
            _rigidbodies = context.Owner.GetComponentsInChildren<UnityEngine.Rigidbody>(true);
            yield break;
        }

        public void Reset()
        {
            if (_rigidbodies == null) return;
            foreach (var body in _rigidbodies)
            {
                if (body == null || body.isKinematic) continue;
                body.linearVelocity = UnityEngine.Vector3.zero;
                body.angularVelocity = UnityEngine.Vector3.zero;
            }
        }

        public void Step(float deltaTime, float physicsFps, int maxSubSteps) { }
        public void Dispose() { }
    }
}