<@include gpu/Config.slh@>
<$VERSION_HEADER$>
//  Generated on <$_SCRIBE_DATE$>
//
//  Created by Sam Gateau on 1/1/16.
//  Copyright 2016 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//

<@include ssao.slh@>
<$declareAmbientOcclusion()$>
<$declareFetchDepthPyramidMap()$>
<$declareSamplingDisk()$>
<$declareEvalObscurance()$>

<$declarePackOcclusionDepth()$>

<@include gpu/color.slh@>
<$declareColorWheel()$>

struct DebugParams{
    vec4 pixelInfo;
};

uniform debugAmbientOcclusionBuffer {
    DebugParams debugParams;
};

vec2 getDebugCursorTexcoord(){
    return debugParams.pixelInfo.xy;
}

out vec4 outFragColor;

void main(void) {
    vec2 imageSize = getSideImageSize(getResolutionLevel());
	
	// In debug adjust the correct frag pixel based on base resolution
	vec2 fragCoord = gl_FragCoord.xy; 
	if (getResolutionLevel() > 0) {
		fragCoord /= float (1 << getResolutionLevel());
	}
	
    // Pixel Debugged
    vec2 cursorUV = getDebugCursorTexcoord();
    vec2 cursorPixelPos = cursorUV * imageSize;

    ivec2 ssC = ivec2(cursorPixelPos);
 
    // Fetch the z under the pixel (stereo or not)
    float Zeye = getZEye(ssC, 0);

    // Stereo side info
    ivec4 side = getStereoSideInfo(ssC.x, getResolutionLevel());

    // From now on, ssC is the pixel pos in the side
    ssC.x -= side.y;
    vec2 fragPos = (vec2(ssC) + vec2(0.5))  / imageSize;

    // The position  and normal of the pixel fragment in Eye space
    vec3 Cp = evalEyePositionFromZeye(side.x, Zeye, fragPos);
    vec3 Cn = evalEyeNormal(Cp);

    // Choose the screen-space sample radius
    float ssDiskRadius = evalDiskRadius(Cp.z, imageSize);

    vec2 fragToCursor = cursorPixelPos - fragCoord.xy;
    if (dot(fragToCursor,fragToCursor) > ssDiskRadius * ssDiskRadius) {
        discard;
    }

    // Let's make noise 
   // float randomPatternRotationAngle = getAngleDithering(ssC);
    float randomPatternRotationAngle = getAngleDitheringWorldPos(Cp);
    

    // Accumulate the Obscurance for each samples
    float sum = 0.0;
    float keepTapRadius = 1.0;
    int keepedMip = -1;
    bool keep = false;

    for (int i = 0; i < getNumSamples(); ++i) {
        vec3 tap = getTapLocationClamped(i, randomPatternRotationAngle, ssDiskRadius, cursorPixelPos, imageSize);
        // The occluding point in camera space
        vec2 fragToTap = vec2(ssC) + tap.xy - fragCoord.xy;
        if (dot(fragToTap,fragToTap) < keepTapRadius) {
            keep = true;
            keepedMip = evalMipFromRadius(tap.z);
        } 

        vec3 Q = getOffsetPosition(side.xyz, ssC, tap, imageSize);

        sum += float(tap.z > 0.0) * evalAO(Cp, Cn, Q);
    }


    float A = max(0.0, 1.0 - sum * getObscuranceScaling() * 5.0 * getInvNumSamples());

    <! // KEEP IT for Debugging
    // Bilateral box-filter over a quad for free, respecting depth edges
    // (the difference that this makes is subtle)
    if (abs(dFdx(Cp.z)) < 0.02) {
        A -= dFdx(A) * ((ssC.x & 1) - 0.5);
    }
    if (abs(dFdy(Cp.z)) < 0.02) {
        A -= dFdy(A) * ((ssC.y & 1) - 0.5);
    }
    !>

    outFragColor = vec4(packOcclusionDepth(A, CSZToDephtKey(Cp.z)), 1.0);

     // KEEP IT for Debugging
    // Debug Normal: outFragColor = vec4((Cn + vec3(1.0))* 0.5, 1.0);
    // Debug Radius outFragColor = vec4(vec3(ssDiskRadius / 100.0), 1.0);
    // Debug MaxMiplevel outFragColor = vec4(1.0 - vec3(float(clamp(findMSB(int(ssDiskRadius)) - LOG_MAX_OFFSET, 0, MAX_MIP_LEVEL))/ float(MAX_MIP_LEVEL)), 1.0);
    // Debug OffsetPosition
   // float ssR;
   // vec2 unitOffset = tapLocation(int(getNumSamples() - 1), 0, ssR);
   // vec3 Q = getOffsetPosition(side, ssC, unitOffset, ssR * ssDiskRadius);
    //outFragColor = vec4(vec3(Q.x / 10.0, Q.y / 2.0, -Q.z/ 3.0), 1.0);
   // vec3 v = normalize(Q - Cp);
    //outFragColor = vec4((v + vec3(1.0))* 0.5, 1.0);
   // outFragColor = vec4((Cn + vec3(1.0))* 0.5, 1.0);
   //outFragColor = vec4(vec3(ssDiskRadius / 100.0), 1.0);

   if ((dot(fragToCursor,fragToCursor) < (100.0 * keepTapRadius * keepTapRadius) )) {
       // outFragColor = vec4(vec3(A), 1.0); 
        outFragColor = vec4(vec3(A), 1.0); 
        return;
   }

   if (!keep) {
     outFragColor = vec4(0.1);
   } else {
    outFragColor.rgb = colorWheel(float(keepedMip)/float(MAX_MIP_LEVEL));
   }
}