using System;
using UnityEngine;

public abstract class ShaderFlagsBase
{
    
    private Material _material;

    public Material material
    {
        get
        {
            return _material;
        }
    }
    
    protected ShaderFlagsBase(Material material)
    {
        _material = material;
    }
    
    public void SetMaterial(Material material)
    {
        _material = material;
    }

    public Material GetMaterial()
    {
        return _material;
    }

    public abstract int GetShaderFlagsId(int index = 0);
    protected abstract string GetShaderFlagsName(int index = 0);

    private void SetIntValue(Material material, int flagBits,int index = 0)
    {
#if UNITY_EDITOR
        material.SetInteger(GetShaderFlagsId(index), flagBits);
#else
        material.SetInteger(GetShaderFlagsId(index), flagBits);
#endif
    }

    public void SetFlagBits(int flagBits, MaterialPropertyBlock propertyBlock = null,int index = 0)
    {
        if (propertyBlock is null)
        {
            if (_material is null) return;
            int flags = _material.GetInteger(GetShaderFlagsId(index));
            SetIntValue(_material, flags | flagBits,index);
        }
        else
        {
            int flags = propertyBlock.GetInt(GetShaderFlagsId(index));
            propertyBlock.SetInt(GetShaderFlagsId(index), flags|flagBits);
        }
    }
    
    public void ClearFlagBits(int flagBits, MaterialPropertyBlock propertyBlock = null,int index = 0)
    {
        if (propertyBlock is null)
        {
            if (_material is null) return;
            int flags = _material.GetInteger(GetShaderFlagsId(index));
            SetIntValue(_material, flags&~flagBits,index);
        }
        else
        {
            int flags = propertyBlock.GetInteger(GetShaderFlagsId(index));
            propertyBlock.SetInteger(GetShaderFlagsId(index), flags&~flagBits);
        }
    }

    public bool CheckFlagBits(int flagBits, MaterialPropertyBlock propertyBlock = null,int index = 0)
    {
        int flags = 0;
        if (propertyBlock is null)
        {
            if (_material is null) throw new NullReferenceException("material");
            flags = _material.GetInteger(GetShaderFlagsId(index));
        }
        else
        {
            flags = propertyBlock.GetInteger(GetShaderFlagsId(index));
        }
        return (flags & flagBits) != 0;
    }
}