using UnityEngine;

[ExecuteInEditMode]
public class PostEffects : MonoBehaviour
{

    [Header("Bloom")]
    public bool isBloomEnabled = true;
    [SerializeField] [Range(1, 8)] int textureReductionFactor = 4;
    [SerializeField] [Range(0, 20)] float bloomIntensity = 2;

    [Header("Motion Blur")]
    public bool isMotionBlurEnabled = true;
    [Header("Static")]
    [SerializeField] [Range(0, 0.8f)] float staticBlurRadius = 0.2f;
    [SerializeField] [Range(0, 10)] float staticBlurSoftness = 0.5f;
    [SerializeField] [Range(0, 10)] float staticBlurIntensity = 0.5f;
    [Header("Motion")]
    [SerializeField] [Range(0, 0.8f)] float motionBlurRadius = 0.2f;
    [SerializeField] [Range(0, 10)] float motionBlurSoftness = 0.5f;
    [SerializeField] [Range(0, 10)] float speedMultiplier = 5f;
    [SerializeField] [Range(0, 10)] float maxMotionBlurIntensity = 5f;

    [Header("Noise")]
    public bool isNoiseEnabled = true;
    [SerializeField] [Range(0, 0.5f)] float noiseSeed = 0.2f;
    [SerializeField] [Range(0, 0.5f)] float noiseIntensity = 0.2f;

    [Header("Vignette")]
    public bool isVignetteEnabled = true;
    [SerializeField] [Range(0, 0.5f)] float vignetteRadius = 0.2f;
    [SerializeField] [Range(0, 10)] float vignetteSoftness = 0.5f;

    [Header("Other")]
    [SerializeField] Material material;
    [SerializeField] Transform carContainer;
    [SerializeField] Transform carCenter;
    [SerializeField] Texture2D lensTexture;
    [SerializeField] [Range(0, 20)] float lensIntensity = 2;
    [HideInInspector] public float saturation = 1;

    Vector3 prevContainerPosition;
    RenderTexture bufferRT;
    Camera cam;

    void OnEnable()
    {
        cam = Camera.main;
        bufferRT = RenderTexture.GetTemporary(cam.pixelWidth / textureReductionFactor, cam.pixelHeight / textureReductionFactor, 0);

        prevContainerPosition = carContainer.position;
        UpdateParams();
    }

    void OnDisable()
    {
        RenderTexture.ReleaseTemporary(bufferRT);
    }

#if UNITY_EDITOR
    void Update()
    {
        UpdateParams();
    }
#endif

    public void UpdateParams()
    {
        material.SetFloat("_NoiseSeed", noiseSeed);
        material.SetFloat("_NoiseIntensity", noiseIntensity);
        material.SetFloat("_VignetteRadius", vignetteRadius);
        material.SetFloat("_VignetteSoftness", vignetteSoftness);
        material.SetFloat("_BloomIntensity", bloomIntensity);
        material.SetFloat("_LensIntensity", lensIntensity);
        material.SetFloat("_Saturation", saturation);
        material.SetTexture("_LensTex", lensTexture);

        SetKeyword(isBloomEnabled, "_BLOOM");
        SetKeyword(isMotionBlurEnabled, "_MOTION_BLUR");
        SetKeyword(isNoiseEnabled, "_NOISE");
        SetKeyword(isVignetteEnabled, "_VIGNETTE");
    }

    void Bloom(RenderTexture src)
    {
        bufferRT.DiscardContents();
        Graphics.Blit(src, bufferRT, material, 0);
        material.SetTexture("_MaskTex", bufferRT);
    }

    void MotionBlur()
    {
        var delta = (carContainer.position - prevContainerPosition).magnitude * speedMultiplier;
        delta = Mathf.Min(delta, maxMotionBlurIntensity);
        prevContainerPosition = carContainer.position;
        bool useWithMotion = delta >= staticBlurIntensity;
        material.SetFloat("_MotionBlurRadius", useWithMotion ? motionBlurRadius : staticBlurRadius);
        material.SetFloat("_MotionBlurSoftness", useWithMotion ? motionBlurSoftness : staticBlurSoftness);
        material.SetVector("_MotionBlurIntensity", useWithMotion ? Vector2.right * delta : Vector2.right * staticBlurIntensity);
        var cp = cam.WorldToViewportPoint(carCenter.position);
        material.SetVector("_CarCenter", new Vector2(cp.x, cp.y));
    }

    public void ProcessImage(RenderTexture src, RenderTexture dst)
    {
        if (isBloomEnabled)
            Bloom(src);
        if (isMotionBlurEnabled)
            MotionBlur();

        Graphics.Blit(src, dst, material, 1);
    }

    void SetKeyword(bool enabled, string keyword)
    {
        if (enabled)
            material.EnableKeyword(keyword);
        else
            material.DisableKeyword(keyword);
    }

}