using System;
using UnityEngine;

namespace RootMotion.FinalIK
{
	[Serializable]
	public class IKSolverAim : IKSolverHeuristic
	{
		public Transform transform;

		public Vector3 axis = Vector3.forward;

		public Vector3 poleAxis = Vector3.up;

		public Vector3 polePosition;

		[Range(0f, 1f)]
		public float poleWeight;

		public Transform poleTarget;

		[Range(0f, 1f)]
		public float clampWeight = 0.1f;

		[Range(0f, 2f)]
		public int clampSmoothing = 2;

		public IterationDelegate OnPreIteration;

		private float step;

		private Vector3 clampedIKPosition;

		private RotationLimit transformLimit;

		private Transform lastTransform;

		public Vector3 transformAxis => transform.rotation * axis;

		public Vector3 transformPoleAxis => transform.rotation * poleAxis;

		protected override int minBones => 1;

		protected override Vector3 localDirection => bones[0].transform.InverseTransformDirection(bones[bones.Length - 1].transform.forward);

		public float GetAngle()
		{
			return Vector3.Angle(transformAxis, IKPosition - transform.position);
		}

		protected override void OnInitiate()
		{
			if ((firstInitiation || !Application.isPlaying) && transform != null)
			{
				IKPosition = transform.position + transformAxis * 3f;
				polePosition = transform.position + transformPoleAxis * 3f;
			}
			for (int i = 0; i < bones.Length; i++)
			{
				if (bones[i].rotationLimit != null)
				{
					bones[i].rotationLimit.Disable();
				}
			}
			step = 1f / (float)bones.Length;
			if (Application.isPlaying)
			{
				axis = axis.normalized;
			}
		}

		protected override void OnUpdate()
		{
			if (axis == Vector3.zero)
			{
				if (!Warning.logged)
				{
					LogWarning("IKSolverAim axis is Vector3.zero.");
				}
				return;
			}
			if (poleAxis == Vector3.zero && poleWeight > 0f)
			{
				if (!Warning.logged)
				{
					LogWarning("IKSolverAim poleAxis is Vector3.zero.");
				}
				return;
			}
			if (target != null)
			{
				IKPosition = target.position;
			}
			if (poleTarget != null)
			{
				polePosition = poleTarget.position;
			}
			if (XY)
			{
				IKPosition.z = bones[0].transform.position.z;
			}
			if (IKPositionWeight <= 0f)
			{
				return;
			}
			IKPositionWeight = Mathf.Clamp(IKPositionWeight, 0f, 1f);
			if (transform != lastTransform)
			{
				transformLimit = transform.GetComponent<RotationLimit>();
				if (transformLimit != null)
				{
					transformLimit.enabled = false;
				}
				lastTransform = transform;
			}
			if (transformLimit != null)
			{
				transformLimit.Apply();
			}
			if (transform == null)
			{
				if (!Warning.logged)
				{
					LogWarning("Aim Transform unassigned in Aim IK solver. Please Assign a Transform (lineal descendant to the last bone in the spine) that you want to be aimed at IKPosition");
				}
				return;
			}
			clampWeight = Mathf.Clamp(clampWeight, 0f, 1f);
			clampedIKPosition = GetClampedIKPosition();
			Vector3 b = clampedIKPosition - transform.position;
			b = Vector3.Slerp(transformAxis * b.magnitude, b, IKPositionWeight);
			clampedIKPosition = transform.position + b;
			for (int i = 0; i < maxIterations && (i < 1 || !(tolerance > 0f) || !(GetAngle() < tolerance)); i++)
			{
				lastLocalDirection = localDirection;
				if (OnPreIteration != null)
				{
					OnPreIteration(i);
				}
				Solve();
			}
			lastLocalDirection = localDirection;
		}

		private void Solve()
		{
			for (int i = 0; i < bones.Length - 1; i++)
			{
				RotateToTarget(clampedIKPosition, bones[i], step * (float)(i + 1) * IKPositionWeight * bones[i].weight);
			}
			RotateToTarget(clampedIKPosition, bones[bones.Length - 1], IKPositionWeight * bones[bones.Length - 1].weight);
		}

		private Vector3 GetClampedIKPosition()
		{
			if (clampWeight <= 0f)
			{
				return IKPosition;
			}
			if (clampWeight >= 1f)
			{
				return transform.position + transformAxis * (IKPosition - transform.position).magnitude;
			}
			float num = Vector3.Angle(transformAxis, IKPosition - transform.position);
			float num2 = 1f - num / 180f;
			float num3 = ((clampWeight > 0f) ? Mathf.Clamp(1f - (clampWeight - num2) / (1f - num2), 0f, 1f) : 1f);
			float num4 = ((clampWeight > 0f) ? Mathf.Clamp(num2 / clampWeight, 0f, 1f) : 1f);
			for (int i = 0; i < clampSmoothing; i++)
			{
				num4 = Mathf.Sin(num4 * MathF.PI * 0.5f);
			}
			return transform.position + Vector3.Slerp(transformAxis * 10f, IKPosition - transform.position, num4 * num3);
		}

		private void RotateToTarget(Vector3 targetPosition, Bone bone, float weight)
		{
			if (XY)
			{
				if (weight >= 0f)
				{
					Vector3 vector = transformAxis;
					Vector3 vector2 = targetPosition - transform.position;
					float current = Mathf.Atan2(vector.x, vector.y) * 57.29578f;
					float num = Mathf.Atan2(vector2.x, vector2.y) * 57.29578f;
					bone.transform.rotation = Quaternion.AngleAxis(Mathf.DeltaAngle(current, num), Vector3.back) * bone.transform.rotation;
				}
			}
			else
			{
				if (weight >= 0f)
				{
					Quaternion quaternion = Quaternion.FromToRotation(transformAxis, targetPosition - transform.position);
					if (weight >= 1f)
					{
						bone.transform.rotation = quaternion * bone.transform.rotation;
					}
					else
					{
						bone.transform.rotation = Quaternion.Lerp(Quaternion.identity, quaternion, weight) * bone.transform.rotation;
					}
				}
				if (poleWeight > 0f)
				{
					Vector3 tangent = polePosition - transform.position;
					Vector3 normal = transformAxis;
					Vector3.OrthoNormalize(ref normal, ref tangent);
					Quaternion b = Quaternion.FromToRotation(transformPoleAxis, tangent);
					bone.transform.rotation = Quaternion.Lerp(Quaternion.identity, b, weight * poleWeight) * bone.transform.rotation;
				}
			}
			if (useRotationLimits && bone.rotationLimit != null)
			{
				bone.rotationLimit.Apply();
			}
		}
	}
}