Shader "Unlit/TerrainWater"
{
    Properties
    {
        
        _MainTex ("Texture", 2D) = "white" {}
        _WaterMask("WaterMask",2D) = "white" {}
        _WaterCol("WaterCol",color) = (1,1,1,1)
        //_WaterFarCol("WaterFarCol",color) = (1,1,1,1)
        _DetailNormal("DetailNormal",2D) = "bump" {}
        _NormalSpeed1("NormalSpeed1",Vector) = (1,1,2,0.5)
        _NormalSpeed2("NormalSpeed2",Vector) = (1,1,2,0.5)
        _NormalSpeed3("NormalSpeed3",Vector) = (1,1,2,0.5)
    }
    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 100

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            // make fog work
            #pragma multi_compile_fog

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
                float4 normal: NORMAL;
                float4 tangent: TANGENT;
            };

            struct v2f
            {
                float4 uv : TEXCOORD0;               
                float4 vertex : SV_POSITION;
                float4 tangentToWorld1: TEXCOORD1;
                float4 tangentToWorld2: TEXCOORD2;
                float4 tangentToWorld3: TEXCOORD3;
            };

            sampler2D _MainTex, _DetailNormal, _WaterMask;
            float4 _MainTex_ST, _DetailNormal_ST, _WaterMask_ST;
            half4 _WaterCol/*, _WaterFarCol*/;
            float4 _NormalSpeed1, _NormalSpeed2, _NormalSpeed3;

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                float3 worldPos = mul(unity_ObjectToWorld, float4(o.vertex.xyz, 1)).xyz;
                o.uv.xy = TRANSFORM_TEX(v.uv, _MainTex); 
                o.uv.zw = TRANSFORM_TEX(v.uv, _DetailNormal);
                float3 worldNormal = UnityObjectToWorldNormal(v.normal);
                float3 worldTangent = UnityObjectToWorldDir(v.tangent.xyz);
                float3 worldBinormal = cross(worldNormal, worldTangent) * v.tangent.w;
                o.tangentToWorld1 = float4(worldTangent.x, worldBinormal.x, worldNormal.x, worldPos.x);
                o.tangentToWorld2 = float4(worldTangent.y, worldBinormal.y, worldNormal.y, worldPos.y);
                o.tangentToWorld3 = float4(worldTangent.z, worldBinormal.z, worldNormal.z, worldPos.z);
                return o;
            }

            half4 frag (v2f i) : SV_Target
            {
                // sample the texture
                fixed4 col = tex2D(_MainTex, i.uv.xy);
                fixed waterFactor = tex2D(_WaterMask, i.uv.xy).r;
                half3 MyNormal1 = UnpackNormal(tex2D(_DetailNormal, i.uv.wz * _NormalSpeed1.zw + _Time.y * normalize(_NormalSpeed1.xy) * 0.3));
                half3 worldMyNormal1 = half3(dot(i.tangentToWorld1.xyz, MyNormal1), dot(i.tangentToWorld2.xyz, MyNormal1), dot(i.tangentToWorld3.xyz, MyNormal1));

                half3 MyNormal2 = UnpackNormal(tex2D(_DetailNormal, i.uv.wz * _NormalSpeed2.zw + _Time.y * normalize(_NormalSpeed2.xy) * 0.3));
                half3 worldMyNormal2 = half3(dot(i.tangentToWorld1.xyz, MyNormal2), dot(i.tangentToWorld2.xyz, MyNormal2), dot(i.tangentToWorld3.xyz, MyNormal2));

                half3 MyNormal3 = UnpackNormal(tex2D(_DetailNormal, i.uv.wz * _NormalSpeed3.zw + _Time.y * normalize(_NormalSpeed3.xy) * 0.3));
                half3 worldMyNormal3 = half3(dot(i.tangentToWorld1.xyz, MyNormal3), dot(i.tangentToWorld2.xyz, MyNormal3), dot(i.tangentToWorld3.xyz, MyNormal3));

                half3 wNormal = worldMyNormal1 + worldMyNormal2 + worldMyNormal3;
                wNormal.xy *= 1;
                //wNormal.z *=0.5;
                wNormal = normalize(wNormal);

               // wNormal = UnityObjectToWorldNormal(wNormal);

                float3 lightDir = normalize(_WorldSpaceLightPos0.xyz);
                float3 worldpos = float3(i.tangentToWorld1.w, i.tangentToWorld2.w, i.tangentToWorld3.w);


               

                fixed3 viewDir = normalize(_WorldSpaceCameraPos - worldpos);
                /*fixed3 halfDir = normalize(viewDir+ lightDir);
                half3 HeightLingt = half3(2, 2, 2) *pow( saturate(dot(halfDir, wNormal)),20)* waterCol;*/

                /*float distance = length(_WorldSpaceCameraPos - worldpos);
                half3 waterBaseCol = lerp(_WaterCol.rgb, _WaterFarCol.rgb, pow(saturate((distance /12000)),5)); */
                half3 waterCol = saturate(dot(wNormal, lightDir)) * _WaterCol.rgb * 0.5 + _WaterCol.rgb * 0.5;

                float3 reflectDir = reflect(-viewDir, wNormal);
                float4 envSamlpe= UNITY_SAMPLE_TEXCUBE(unity_SpecCube0, reflectDir);
                half3 refecltCol = DecodeHDR(envSamlpe, unity_SpecCube0_HDR);

                half3 finalWaterCol = waterCol /*+ HeightLingt*/+ refecltCol*0.4;
               
                half4 fnialCol = half4(lerp(col.rgb, finalWaterCol, waterFactor), 1);
                return fnialCol;
            }
            ENDCG
        }
    }
}