Convert to surface shader

Hi all!Please help me convert this shader into surface shader.
Shader "AlphaTexturing" {
Properties {
_AO("АО",2D)="white"{}
_MainTex ("Main Texture", 2D) = "white" {}
_Mask ("Mask Texture", 2D) = "white" {}
_MainTex2 ("Main Texture", 2D) = "white" {}
_Mask2 ("Mask Texture", 2D) = "white" {}
_Color("",Color)=(0,0,0,0)
}
SubShader {

Blend SrcAlpha OneMinusSrcAlpha
Lighting On

Pass{
SetTexture [_AO] {combine texture*texture,previous}
}
Pass
{


SetTexture [_Mask] {combine texture}

SetTexture [_MainTex] {combine texture, previous}

}
Pass
{

SetTexture [_Mask2] {combine texture}

SetTexture [_MainTex2] {combine texture, previous}


}

}


}

 

Oooh my gooodd