using System.Collections.Generic;
using UnityEngine;

namespace BF
{
    [RequireComponent(typeof(Camera))]
    [ExecuteInEditMode]
    [DisallowMultipleComponent]
    public class PostEffectBehaviour : MonoBehaviour
    {
        PostEffectType effectType = PostEffectType.None;
        public PostEffectType EffectType
        {
            get { return effectType; }
            private set { effectType = value; SetDirty(); }
        }

        public PostEffectVividBloom VividBloomEffect { get; private set; }
        public PostEffectFxaa FxaaEffect { get; private set; }
        public PostEffectRadialBlur RadialBlurEffetc { get; private set; }

        bool hasEffect;
        bool inited;
        bool support;
        PostEffectContext context = new PostEffectContext();
        List<AbsPostEffect> curActiveEffects = new List<AbsPostEffect>();

        void Awake()
        {
            if (!CheckSupport())
            {
                enabled = false;
                support = false;
                return;
            }
            else
            {
                support = true;
                Init();
                SetDirty();
            }
        }

        public bool CheckSupport()
        {
            return true;
        }

        public void Init()
        {
            if (!inited)
            {
                VividBloomEffect = new PostEffectVividBloom();
                FxaaEffect = new PostEffectFxaa();
                RadialBlurEffetc = new PostEffectRadialBlur();
                inited = true;
            }
        }

        public void SetPostEffectType(PostEffectType type)
        {
            EffectType = type;
        }

        public void OpenPostEffect(PostEffectType effectType)
        {
            EffectType |= effectType;
        }

        public void ClosePostEffect(PostEffectType effectType)
        {
            if ((this.effectType & effectType) != 0)
            {
                EffectType ^= effectType;
            }
        }

        void SetDirty()
        {
            if (!support)
            {
                return;
            }
            if (!inited)
            {
                Init();
            }

            curActiveEffects.Clear();
            hasEffect = enabled = EffectType != PostEffectType.None;

            VividBloomEffect.active = (EffectType & PostEffectType.VividBloom) != 0;
            if (VividBloomEffect.active)
            {
                curActiveEffects.Add(VividBloomEffect);
            }

            RadialBlurEffetc.active = (EffectType & PostEffectType.RadialBlur) != 0;
            if (RadialBlurEffetc.active)
            {
                curActiveEffects.Add(RadialBlurEffetc);
            }


            FxaaEffect.active = (EffectType & PostEffectType.Fxaa) != 0;
            if (FxaaEffect.active)
            {
                curActiveEffects.Add(FxaaEffect);
            }
        }

        void OnRenderImage(RenderTexture src, RenderTexture dest)
        {
            if (hasEffect)
            {
                var count = curActiveEffects.Count;
                context.src = src;
                context.dest = dest;
                for (var i = 0; i < count - 1; i++)
                {
                    context = curActiveEffects[i].OnRenderImage(context);
                    Graphics.Blit(dest, src);
                }
                curActiveEffects[count - 1].OnRenderImage(context);
            }
            else
            {
                Graphics.Blit(src, dest);
            }
        }

        void OnDestroy()
        {
        }
    }
}