Shader "LowPolyWater/WaterShaded_Ortho_Final" {
Properties { 
    _BaseColor ("Base color", COLOR)  = ( .54, .95, .99, 0.5) 
    _SpecColor ("Specular Material Color", Color) = (1,1,1,1) 
    _Shininess ("Shininess", Float) = 10
    
    _FoamColor ("Foam Color", Color) = (1,1,1,1)
    _ShoreTex ("Shore & Foam texture ", 2D) = "black" {} 
     
    _InvFadeParemeter ("Shore Thickness (X), Foam Spread (Y)", Vector) = (5.0 ,2.0, 0.5, 1.0)

    _BumpTiling ("Foam Tiling", Vector) = (1.0 ,1.0, -2.0, 3.0)
    _BumpDirection ("Foam movement", Vector) = (1.0 ,1.0, -1.0, 1.0) 

    _Foam ("Foam (intensity, cutoff)", Vector) = (0.5, 0.375, 0.0, 0.0) 
    [MaterialToggle] _isInnerAlphaBlendOrColor("Fade inner to color or alpha?", Float) = 0 
}

Subshader {
    Tags {"RenderType"="Transparent" "Queue"="Transparent"}
    Lod 500
    
    Pass {
        Blend SrcAlpha OneMinusSrcAlpha
        ZTest LEqual
        ZWrite Off
        Cull Off
    
        CGPROGRAM
        #pragma vertex vert
        #pragma fragment frag
        #pragma multi_compile_fog
        #pragma multi_compile WATER_EDGEBLEND_ON WATER_EDGEBLEND_OFF 
        #pragma target 3.0
        
        #include "UnityCG.cginc" 

        sampler2D _ShoreTex;
        sampler2D_float _CameraDepthTexture;
      
        float4 _BaseColor;  
        float4 _FoamColor;
        float _SpecColor;
        float _Shininess;
        float4 _InvFadeParemeter;
        float4 _BumpTiling;
        float4 _BumpDirection;
        float4 _Foam; 
        float _isInnerAlphaBlendOrColor; 

        struct v2f {
            float4 pos : SV_POSITION;
            float4 screenPos : TEXCOORD3;
            float4 bumpCoords : TEXCOORD4;
            float3 worldPos : TEXCOORD5;
            float3 worldNormal : TEXCOORD6;
            UNITY_FOG_COORDS(7)
        }; 

        v2f vert(appdata_full v) {
            v2f o;
            // The vertex position here will include any changes made by your C# script 
            // if you are modifying the mesh filter's vertices.
            o.pos = UnityObjectToClipPos(v.vertex);
            o.screenPos = ComputeScreenPos(o.pos);
            COMPUTE_EYEDEPTH(o.screenPos.z);
            
            o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;
            o.worldNormal = UnityObjectToWorldNormal(v.normal);
            
            o.bumpCoords.xyzw = (o.worldPos.xzxz + _Time.xxxx * _BumpDirection.xyzw) * _BumpTiling.xyzw;
            
            UNITY_TRANSFER_FOG(o, o.pos);
            return o;
        }

        half4 frag(v2f i) : SV_Target { 
            // 1. Calculate Depth for Ortho
            float rawDepth = SAMPLE_DEPTH_TEXTURE_PROJ(_CameraDepthTexture, UNITY_PROJ_COORD(i.screenPos));
            float sceneZ = LinearEyeDepth(rawDepth);
            float waterZ = i.screenPos.z;
            float diff = sceneZ - waterZ;

            // 2. Foam Factors
            // edgeFactor is the solid line. foamFactor is the textured area.
            float edgeFactor = saturate(_InvFadeParemeter.x * diff);
            float foamFactor = saturate(_InvFadeParemeter.y * diff);

            // 3. Lighting
            float3 lightDir = normalize(_WorldSpaceLightPos0.xyz);
            float diffExp = max(0.1, dot(i.worldNormal, lightDir)); // Simple wrap lighting
            float4 finalCol = float4(_BaseColor.rgb * diffExp, _BaseColor.a);

            // 4. Foam Texturing
            float4 foamTex = (tex2D(_ShoreTex, i.bumpCoords.xy) * tex2D(_ShoreTex, i.bumpCoords.zw));
            
            // Add the "Shore Line" using the Foam Color (White by default)
            float shoreStrength = (1.0 - edgeFactor);
            finalCol.rgb = lerp(finalCol.rgb, _FoamColor.rgb, shoreStrength);
            
            // Add the "Foam Bubbles" texture near the edges
            float texturedFoam = foamTex.r * (1.0 - foamFactor) * _Foam.x;
            finalCol.rgb += _FoamColor.rgb * texturedFoam;

            // 5. Alpha handling
            if(_isInnerAlphaBlendOrColor > 0) {
                finalCol.a = edgeFactor;
            }

            UNITY_APPLY_FOG(i.fogCoord, finalCol);
            return finalCol;
        }
        ENDCG
    }
}
Fallback "Transparent/Diffuse"
}