using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Rendering;

[CreateAssetMenu(fileName = "VisualStyle", menuName = "UniQuake/Visual Style", order = 1)]
public class VisualStyle : ScriptableObject
{
    [SerializeField]
    protected Material entityMaterial;

    [SerializeField]
    protected Material worldMaterial;    // TODO: split into wall, liquid, sky, etc

    [SerializeField]
    protected Material liquidMaterial;

    [SerializeField]
    protected bool pointSampling;
    
    [SerializeField]
    protected bool affineTexturing;

    [SerializeField] 
    protected LiquidProperties liquidProperties = new LiquidProperties();

    [SerializeField]
    protected ParticleSystems particles = new ParticleSystems();
    public ParticleSystems Particles => particles;

    public virtual void Activate()
    {
        if (pointSampling)
            Shader.EnableKeyword("_POINT_SAMPLING");
        else
            Shader.DisableKeyword("_POINT_SAMPLING");
    }
    
    public virtual Material CreateEntityMaterial(bool aliasModel)
    {
        var material = new Material(entityMaterial);
        
        if (aliasModel && affineTexturing)
            material.EnableKeyword("_AFFINE_ON");
        else
            material.DisableKeyword("_AFFINE_ON");

        return material;
    }

    public virtual Material CreateWorldMaterial(QSurfaceFlags surfaceFlags)
    {
        Material material;
        
        if (surfaceFlags.HasFlag(QSurfaceFlags.DrawTurbulence) && liquidMaterial != null)
        {
            float alpha = 1f;
            if (surfaceFlags.HasFlag(QSurfaceFlags.DrawWater))
                alpha = liquidProperties.waterAlpha;
            else if (surfaceFlags.HasFlag(QSurfaceFlags.DrawSlime))
                alpha = liquidProperties.slimeAlpha;
            else if (surfaceFlags.HasFlag(QSurfaceFlags.DrawLava))
                alpha = liquidProperties.lavaAlpha;
            else if (surfaceFlags.HasFlag(QSurfaceFlags.DrawTeleporter))
                alpha = liquidProperties.teleAlpha;

            material = new Material(liquidMaterial);
            material.SetColor("_BaseColor", new Color(1, 1, 1, alpha));
        }
        else
        {
            material = new Material(worldMaterial);
        }
        
        if (surfaceFlags.HasFlag(QSurfaceFlags.DrawFence))
        {
            material.EnableKeyword("_ALPHATEST_ON");
        }

        return material;
    }
    
    public virtual void SetupEntityRenderer(MeshRenderer meshRenderer)
    {
        meshRenderer.shadowCastingMode = ShadowCastingMode.Off;
        meshRenderer.receiveShadows = false;
        meshRenderer.lightProbeUsage = LightProbeUsage.Off;
        meshRenderer.reflectionProbeUsage = ReflectionProbeUsage.Off;
    }

    public virtual void SetupEntityRenderer(SkinnedMeshRenderer skinnedMeshRenderer)
    {
        skinnedMeshRenderer.shadowCastingMode = ShadowCastingMode.Off;
        skinnedMeshRenderer.receiveShadows = false;
        skinnedMeshRenderer.lightProbeUsage = LightProbeUsage.Off;
        skinnedMeshRenderer.reflectionProbeUsage = ReflectionProbeUsage.Off;
    }

    public virtual void SetupWorldRenderer(MeshRenderer meshRenderer)
    {
        meshRenderer.shadowCastingMode = ShadowCastingMode.Off;
        meshRenderer.receiveShadows = false;
        meshRenderer.lightProbeUsage = LightProbeUsage.Off;
        meshRenderer.reflectionProbeUsage = ReflectionProbeUsage.Off;
    }

    public virtual void SetEntityTextures(Material material, Texture2D mainTexture, Texture2D fullBright)
    {
        material.mainTexture = mainTexture;

        material.SetTexture("_EmissionMap", fullBright);
        material.SetColor("_EmissionColor", Color.white);
        
        if (fullBright != null)
            material.EnableKeyword("_EMISSION");
        else
            material.DisableKeyword("_EMISSION");
    }

    public virtual void SetWorldTextures(Material material, Texture2D mainTexture, Texture2D fullBright, Texture2D lightmap)
    {
        material.mainTexture = mainTexture;

        material.SetTexture("_EmissionMap", fullBright);
        material.SetColor("_EmissionColor", Color.white);
        
        if (fullBright != null)
            material.EnableKeyword("_EMISSION");
        else
            material.DisableKeyword("_EMISSION");

        material.SetTexture("_LightMap", lightmap);
        
        if (lightmap != null)
            material.EnableKeyword("_QLIGHTMAP_ON");
        else
            material.DisableKeyword("_QLIGHTMAP_ON");
    }
}

[System.Serializable]
public class LiquidProperties
{
    [Range(0, 1)]
    public float
        waterAlpha = 0.85f,
        slimeAlpha = 0.9f,
        lavaAlpha = 0.95f,
        teleAlpha = 1.0f;
}

[System.Serializable]
public class ParticleSystems
{
    [SerializeField]
    protected ParticleSystem explosion;

    public virtual void CreateExplosion(Vector3 position, Layers layer)
    {
        if (explosion == null)
            return;
    
        var go = Object.Instantiate(explosion.gameObject);
        go.transform.position = position;
        SetLayer(go, layer);
    }

    protected static void SetLayer(GameObject go, Layers layer)
    {
        go.layer = (int)layer;

        int childCount = go.transform.childCount;
        for (int i = 0; i < childCount; ++i)
        {
            go.transform.GetChild(i).gameObject.layer = (int)layer;
        }
    }
}