using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Aiwaz.Contracts;

namespace Aiwaz.Resources
{
    public class Bone : IBone
    {
        #region IBone Members

        private SlimDX.Matrix transformation;
        private SlimDX.Matrix invPoseTransformation;
        private float lastAnimationTime = float.MinValue;
        private IBone parent;
        private SlimDX.Matrix[] matrixArray = new SlimDX.Matrix[0];
        private ITransformationAnimation transformationAnimation;
        private Dictionary<int, IBone> boneIndexList = new Dictionary<int, IBone>();

        public Bone(string name, int index, SlimDX.Vector3 poseTranslation, SlimDX.Vector3 poseScale, SlimDX.Quaternion poseRotation)
        {
            PoseTransformation = SlimDX.Matrix.Transformation(SlimDX.Vector3.Zero, SlimDX.Quaternion.Identity, poseScale, SlimDX.Vector3.Zero, poseRotation, poseTranslation);
            invPoseTransformation = this.PoseTransformation;
            invPoseTransformation.Invert();
            this.Index = index;
            this.ChildBones = new List<IBone>();
        }

        public SlimDX.Matrix GetTransformationAtTime(float time, SlimDX.Matrix rootTransformationMatrix)
        {
            if (this.TransformationAnimation != null)
            {
                if (time != lastAnimationTime)
                {
                    if (this.Parent != null)
                    {
                        transformation = (this.TransformationAnimation.GetTransformationAtTime(time) * invPoseTransformation) * this.Parent.GetTransformationAtTime(time, rootTransformationMatrix);
                        transformation = invPoseTransformation * this.TransformationAnimation.GetTransformationAtTime(time);
                        //m_Transformation = m_Transformation * ( * m_InvPoseTransformation);
                    }
                    else
                        transformation = this.TransformationAnimation.GetTransformationAtTime(time) * invPoseTransformation;
                }
            }
            return transformation;
        }
        
        public Dictionary<int, IBone> BoneIndexList
        {
            get
            {
                if (parent != null)
                    return parent.BoneIndexList;

                if (boneIndexList.Count == 0)
                    this.FillBoneIndexList(this);

                return boneIndexList;
            }
        }

        public List<IBone> ChildBones { get; protected set; }

        public int Index { get; protected set; }

        public SlimDX.Matrix[] MatrixArray
        {
            get
            {
                if (matrixArray == null)
                    matrixArray = new SlimDX.Matrix[this.BoneIndexList.Count];
                return matrixArray;
            }
        }

        public string Name { get; protected set; }

        public SlimDX.Matrix PoseTransformation { get; protected set; }

        public IBone Parent
        {
            get { return parent; }
            set
            {
                if (parent != null)
                    parent.ChildBones.Remove(this);
	            parent = value;
                if (parent != null)
		            parent.ChildBones.Add(this);
            }
        }
        
        public ITransformationAnimation TransformationAnimation
        {
            get { return transformationAnimation; }
            set
            {
                transformationAnimation = value;
                lastAnimationTime = float.MinValue;
                transformation = new SlimDX.Matrix();
            }
        }

        internal void FillBoneIndexList(IBone currentBone)
        {
            boneIndexList[currentBone.Index] = currentBone;
            foreach (var childBone in currentBone.ChildBones)
                this.FillBoneIndexList(childBone);
        }


        #endregion
    }
}