using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System;
using System.Linq;

public class BlendShapeExample : MonoBehaviour
{
    private int blendShapeCount;
    private SkinnedMeshRenderer skinnedMeshRenderer;
    private Mesh skinnedMesh;
    private Dictionary<int, string> shapekeyIndex = new Dictionary<int, string>();
    private Dictionary<string, int> shapekeyIndexR = new Dictionary<string, int>();
    private Dictionary<int, List<int>> correctiveIndex = new Dictionary<int, List<int>>();

    void Awake()
    {
        this.skinnedMeshRenderer = GetComponent<SkinnedMeshRenderer>();
        this.skinnedMesh = GetComponent<SkinnedMeshRenderer>().sharedMesh;
    }

    void Start()
    {
        this.blendShapeCount = skinnedMesh.blendShapeCount;
        for (int i = 0; i < this.blendShapeCount; i++)
        {
            string s = this.skinnedMesh.GetBlendShapeName(i);
            this.shapekeyIndex.Add(i, s);
            this.shapekeyIndexR.Add(s, i);
        }
        for (int i = 0; i < this.blendShapeCount; i++)
        {
            string s = this.skinnedMesh.GetBlendShapeName(i);
            if (s.Contains('_'))
            {
                var ctrls = new List<int>();
                foreach (var sub in s.Split('_', StringSplitOptions.RemoveEmptyEntries))
                {
                    ctrls.Add(shapekeyIndexR[sub]);
                }
                this.correctiveIndex.Add(i, ctrls);
            }
        }
    }

    void Update()
    {
        foreach (var item in this.correctiveIndex)
        {
            float weight = 1.0f;
            foreach (var index in item.Value)
            {
                weight *= this.skinnedMeshRenderer.GetBlendShapeWeight(index) * 0.01f;
            }
            this.skinnedMeshRenderer.SetBlendShapeWeight(item.Key, weight * 100);
        }
    }
}