using System;
using UnityEngine;
using UnityEngine.Playables;
using UnityEngine.Timeline;

public class MatControlMixerBehaviour : PlayableBehaviour
{

    Color m_DefaultColor;
    Color m_DefaultEmissionColor;
    Renderer m_TrackBinding;
    bool init = false;
    float inputWeight = 0;
    public override void ProcessFrame(Playable playable, FrameData info, object playerData)
    {
        m_TrackBinding = playerData as Renderer;

        if (m_TrackBinding == null)
            return;

        if (!init)
        {
            init = true;
            if (Application.isPlaying)
            {
                // 复制材质球
                m_DefaultColor = m_TrackBinding.material.color;
                m_DefaultEmissionColor = GetEmissionColor(m_TrackBinding);
            }
                
        }
        int inputCount = playable.GetInputCount();

        for (int i = 0; i < inputCount; i++)
        {
            inputWeight = playable.GetInputWeight(i);
            if (inputWeight == 0)
                continue;

            // float blend = (float)playable.GetTime();
            
            // Debug.Log("cur weight = " + inputWeight);
            ScriptPlayable<MatControlBehaviour> inputPlayable = (ScriptPlayable<MatControlBehaviour>)playable.GetInput(i);
            MatControlBehaviour input = inputPlayable.GetBehaviour();
            // Debug.Log(input.Clip.start + "  " + input.Clip.end);
            if (input.isContinued)
            {
                if (Application.isPlaying)
                {
                    m_TrackBinding.sharedMaterial.color = input.color;
                    m_DefaultColor = input.color;
                }

                continue;
            }
            Playable PlayableDir = playable.GetGraph().GetRootPlayable(0);
            float playtime = (float)PlayableDir.GetTime();
            float colorWeight = Mathf.InverseLerp((float)input.Clip.start, (float)input.Clip.end, playtime);
            // Debug.Log("colorWeight = " + colorWeight);
            if (Application.isPlaying)
            {
                // PlayableDir.Pause();
                m_TrackBinding.sharedMaterial.color = Color.Lerp(m_DefaultColor, input.color, colorWeight);
                if (input.isEmission)
                {
                    Color c = Color.Lerp(m_DefaultEmissionColor, input.Emission, colorWeight);
                    SetEmissionColor(m_TrackBinding, c);
                }
            }
        }
    }

    public Color GetEmissionColor(Renderer r)
    {
        if (r.sharedMaterial.IsKeywordEnabled("_EMISSION"))
        {
            return r.sharedMaterial.GetColor("_EmissionColor");
        }
        return Color.clear;
    }

    public void SetEmissionColor(Renderer r, Color c)
    {
        if (r.sharedMaterial.IsKeywordEnabled("_EMISSION"))
        {
            r.sharedMaterial.SetColor("_EmissionColor", c);
        }
    }

    public override void OnPlayableDestroy(Playable playable)
    {
        ResetColor();
        base.OnPlayableDestroy(playable);
    }

    public override void OnGraphStop(Playable playable)
    {
        ResetColor();
        base.OnGraphStop(playable);
    }

    public override void OnGraphStart(Playable playable)
    {
        ResetColor();
        base.OnGraphStart(playable);
    }

    public override void OnBehaviourPlay(Playable playable, FrameData info)
    {
        ResetColor();
        base.OnBehaviourPlay(playable, info);
    }

    public override void OnBehaviourPause(Playable playable, FrameData info)
    {
        ResetColor();
        base.OnBehaviourPause(playable, info);
    }


    public void ResetColor()
    {
        if (m_TrackBinding != null)
        {
            if (Application.isPlaying)
            {
                m_TrackBinding.sharedMaterial.color = m_DefaultColor;
                if (m_TrackBinding.sharedMaterial.IsKeywordEnabled("_EMISSION"))
                {
                    m_TrackBinding.sharedMaterial.SetColor("_EmissionColor", m_DefaultEmissionColor);
                }
            }
        }
    }

}