import {
	Vector2
} from '../../../build/three.module.js';

/**
 * Depth-of-field shader with bokeh
 * ported from GLSL shader by Martins Upitis
 * http://blenderartists.org/forum/showthread.php?237488-GLSL-depth-of-field-with-bokeh-v2-4-(update)
 *
 * Requires #define RINGS and SAMPLES integers
 */



var BokehShader = {

	uniforms: {

		'textureWidth': { value: 1.0 },
		'textureHeight': { value: 1.0 },

		'focalDepth': { value: 1.0 },
		'focalLength': { value: 24.0 },
		'fstop': { value: 0.9 },

		'tColor': { value: null },
		'tDepth': { value: null },

		'maxblur': { value: 1.0 },

		'showFocus': { value: 0 },
		'manualdof': { value: 0 },
		'vignetting': { value: 0 },
		'depthblur': { value: 0 },

		'threshold': { value: 0.5 },
		'gain': { value: 2.0 },
		'bias': { value: 0.5 },
		'fringe': { value: 0.7 },

		'znear': { value: 0.1 },
		'zfar': { value: 100 },

		'noise': { value: 1 },
		'dithering': { value: 0.0001 },
		'pentagon': { value: 0 },

		'shaderFocus': { value: 1 },
		'focusCoords': { value: new Vector2() }


	},

	vertexShader: [

		'varying vec2 vUv;',

		'void main() {',

		'	vUv = uv;',
		'	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );',

		'}'

	].join( '\n' ),

	fragmentShader: [

		'#include <common>',

		'varying vec2 vUv;',

		'uniform sampler2D tColor;',
		'uniform sampler2D tDepth;',
		'uniform float textureWidth;',
		'uniform float textureHeight;',

		'uniform float focalDepth;  //focal distance value in meters, but you may use autofocus option below',
		'uniform float focalLength; //focal length in mm',
		'uniform float fstop; //f-stop value',
		'uniform bool showFocus; //show debug focus point and focal range (red = focal point, green = focal range)',

		'/*',
		'make sure that these two values are the same for your camera, otherwise distances will be wrong.',
		'*/',

		'uniform float znear; // camera clipping start',
		'uniform float zfar; // camera clipping end',

		'//------------------------------------------',
		'//user variables',

		'const int samples = SAMPLES; //samples on the first ring',
		'const int rings = RINGS; //ring count',

		'const int maxringsamples = rings * samples;',

		'uniform bool manualdof; // manual dof calculation',
		'float ndofstart = 1.0; // near dof blur start',
		'float ndofdist = 2.0; // near dof blur falloff distance',
		'float fdofstart = 1.0; // far dof blur start',
		'float fdofdist = 3.0; // far dof blur falloff distance',

		'float CoC = 0.03; //circle of confusion size in mm (35mm film = 0.03mm)',

		'uniform bool vignetting; // use optical lens vignetting',

		'float vignout = 1.3; // vignetting outer border',
		'float vignin = 0.0; // vignetting inner border',
		'float vignfade = 22.0; // f-stops till vignete fades',

		'uniform bool shaderFocus;',
		'// disable if you use external focalDepth value',

		'uniform vec2 focusCoords;',
		'// autofocus point on screen (0.0,0.0 - left lower corner, 1.0,1.0 - upper right)',
		'// if center of screen use vec2(0.5, 0.5);',

		'uniform float maxblur;',
		'//clamp value of max blur (0.0 = no blur, 1.0 default)',

		'uniform float threshold; // highlight threshold;',
		'uniform float gain; // highlight gain;',

		'uniform float bias; // bokeh edge bias',
		'uniform float fringe; // bokeh chromatic aberration / fringing',

		'uniform bool noise; //use noise instead of pattern for sample dithering',

		'uniform float dithering;',

		'uniform bool depthblur; // blur the depth buffer',
		'float dbsize = 1.25; // depth blur size',

		'/*',
		'next part is experimental',
		'not looking good with small sample and ring count',
		'looks okay starting from samples = 4, rings = 4',
		'*/',

		'uniform bool pentagon; //use pentagon as bokeh shape?',
		'float feather = 0.4; //pentagon shape feather',

		'//------------------------------------------',

		'float penta(vec2 coords) {',
		'	//pentagonal shape',
		'	float scale = float(rings) - 1.3;',
		'	vec4  HS0 = vec4( 1.0,         0.0,         0.0,  1.0);',
		'	vec4  HS1 = vec4( 0.309016994, 0.951056516, 0.0,  1.0);',
		'	vec4  HS2 = vec4(-0.809016994, 0.587785252, 0.0,  1.0);',
		'	vec4  HS3 = vec4(-0.809016994,-0.587785252, 0.0,  1.0);',
		'	vec4  HS4 = vec4( 0.309016994,-0.951056516, 0.0,  1.0);',
		'	vec4  HS5 = vec4( 0.0        ,0.0         , 1.0,  1.0);',

		'	vec4  one = vec4( 1.0 );',

		'	vec4 P = vec4((coords),vec2(scale, scale));',

		'	vec4 dist = vec4(0.0);',
		'	float inorout = -4.0;',

		'	dist.x = dot( P, HS0 );',
		'	dist.y = dot( P, HS1 );',
		'	dist.z = dot( P, HS2 );',
		'	dist.w = dot( P, HS3 );',

		'	dist = smoothstep( -feather, feather, dist );',

		'	inorout += dot( dist, one );',

		'	dist.x = dot( P, HS4 );',
		'	dist.y = HS5.w - abs( P.z );',

		'	dist = smoothstep( -feather, feather, dist );',
		'	inorout += dist.x;',

		'	return clamp( inorout, 0.0, 1.0 );',
		'}',

		'float bdepth(vec2 coords) {',
		'	// Depth buffer blur',
		'	float d = 0.0;',
		'	float kernel[9];',
		'	vec2 offset[9];',

		'	vec2 wh = vec2(1.0/textureWidth,1.0/textureHeight) * dbsize;',

		'	offset[0] = vec2(-wh.x,-wh.y);',
		'	offset[1] = vec2( 0.0, -wh.y);',
		'	offset[2] = vec2( wh.x -wh.y);',

		'	offset[3] = vec2(-wh.x,  0.0);',
		'	offset[4] = vec2( 0.0,   0.0);',
		'	offset[5] = vec2( wh.x,  0.0);',

		'	offset[6] = vec2(-wh.x, wh.y);',
		'	offset[7] = vec2( 0.0,  wh.y);',
		'	offset[8] = vec2( wh.x, wh.y);',

		'	kernel[0] = 1.0/16.0;   kernel[1] = 2.0/16.0;   kernel[2] = 1.0/16.0;',
		'	kernel[3] = 2.0/16.0;   kernel[4] = 4.0/16.0;   kernel[5] = 2.0/16.0;',
		'	kernel[6] = 1.0/16.0;   kernel[7] = 2.0/16.0;   kernel[8] = 1.0/16.0;',


		'	for( int i=0; i<9; i++ ) {',
		'		float tmp = texture2D(tDepth, coords + offset[i]).r;',
		'		d += tmp * kernel[i];',
		'	}',

		'	return d;',
		'}',


		'vec3 color(vec2 coords,float blur) {',
		'	//processing the sample',

		'	vec3 col = vec3(0.0);',
		'	vec2 texel = vec2(1.0/textureWidth,1.0/textureHeight);',

		'	col.r = texture2D(tColor,coords + vec2(0.0,1.0)*texel*fringe*blur).r;',
		'	col.g = texture2D(tColor,coords + vec2(-0.866,-0.5)*texel*fringe*blur).g;',
		'	col.b = texture2D(tColor,coords + vec2(0.866,-0.5)*texel*fringe*blur).b;',

		'	vec3 lumcoeff = vec3(0.299,0.587,0.114);',
		'	float lum = dot(col.rgb, lumcoeff);',
		'	float thresh = max((lum-threshold)*gain, 0.0);',
		'	return col+mix(vec3(0.0),col,thresh*blur);',
		'}',

		'vec3 debugFocus(vec3 col, float blur, float depth) {',
		'	float edge = 0.002*depth; //distance based edge smoothing',
		'	float m = clamp(smoothstep(0.0,edge,blur),0.0,1.0);',
		'	float e = clamp(smoothstep(1.0-edge,1.0,blur),0.0,1.0);',

		'	col = mix(col,vec3(1.0,0.5,0.0),(1.0-m)*0.6);',
		'	col = mix(col,vec3(0.0,0.5,1.0),((1.0-e)-(1.0-m))*0.2);',

		'	return col;',
		'}',

		'float linearize(float depth) {',
		'	return -zfar * znear / (depth * (zfar - znear) - zfar);',
		'}',


		'float vignette() {',
		'	float dist = distance(vUv.xy, vec2(0.5,0.5));',
		'	dist = smoothstep(vignout+(fstop/vignfade), vignin+(fstop/vignfade), dist);',
		'	return clamp(dist,0.0,1.0);',
		'}',

		'float gather(float i, float j, int ringsamples, inout vec3 col, float w, float h, float blur) {',
		'	float rings2 = float(rings);',
		'	float step = PI*2.0 / float(ringsamples);',
		'	float pw = cos(j*step)*i;',
		'	float ph = sin(j*step)*i;',
		'	float p = 1.0;',
		'	if (pentagon) {',
		'		p = penta(vec2(pw,ph));',
		'	}',
		'	col += color(vUv.xy + vec2(pw*w,ph*h), blur) * mix(1.0, i/rings2, bias) * p;',
		'	return 1.0 * mix(1.0, i /rings2, bias) * p;',
		'}',

		'void main() {',
		'	//scene depth calculation',

		'	float depth = linearize(texture2D(tDepth,vUv.xy).x);',

		'	// Blur depth?',
		'	if ( depthblur ) {',
		'		depth = linearize(bdepth(vUv.xy));',
		'	}',

		'	//focal plane calculation',

		'	float fDepth = focalDepth;',

		'	if (shaderFocus) {',

		'		fDepth = linearize(texture2D(tDepth,focusCoords).x);',

		'	}',

		'	// dof blur factor calculation',

		'	float blur = 0.0;',

		'	if (manualdof) {',
		'		float a = depth-fDepth; // Focal plane',
		'		float b = (a-fdofstart)/fdofdist; // Far DoF',
		'		float c = (-a-ndofstart)/ndofdist; // Near Dof',
		'		blur = (a>0.0) ? b : c;',
		'	} else {',
		'		float f = focalLength; // focal length in mm',
		'		float d = fDepth*1000.0; // focal plane in mm',
		'		float o = depth*1000.0; // depth in mm',

		'		float a = (o*f)/(o-f);',
		'		float b = (d*f)/(d-f);',
		'		float c = (d-f)/(d*fstop*CoC);',

		'		blur = abs(a-b)*c;',
		'	}',

		'	blur = clamp(blur,0.0,1.0);',

		'	// calculation of pattern for dithering',

		'	vec2 noise = vec2(rand(vUv.xy), rand( vUv.xy + vec2( 0.4, 0.6 ) ) )*dithering*blur;',

		'	// getting blur x and y step factor',

		'	float w = (1.0/textureWidth)*blur*maxblur+noise.x;',
		'	float h = (1.0/textureHeight)*blur*maxblur+noise.y;',

		'	// calculation of final color',

		'	vec3 col = vec3(0.0);',

		'	if(blur < 0.05) {',
		'		//some optimization thingy',
		'		col = texture2D(tColor, vUv.xy).rgb;',
		'	} else {',
		'		col = texture2D(tColor, vUv.xy).rgb;',
		'		float s = 1.0;',
		'		int ringsamples;',

		'		for (int i = 1; i <= rings; i++) {',
		'			/*unboxstart*/',
		'			ringsamples = i * samples;',

		'			for (int j = 0 ; j < maxringsamples ; j++) {',
		'				if (j >= ringsamples) break;',
		'				s += gather(float(i), float(j), ringsamples, col, w, h, blur);',
		'			}',
		'			/*unboxend*/',
		'		}',

		'		col /= s; //divide by sample count',
		'	}',

		'	if (showFocus) {',
		'		col = debugFocus(col, blur, depth);',
		'	}',

		'	if (vignetting) {',
		'		col *= vignette();',
		'	}',

		'	gl_FragColor.rgb = col;',
		'	gl_FragColor.a = 1.0;',
		'} '

	].join( '\n' )

};

var BokehDepthShader = {

	uniforms: {

		'mNear': { value: 1.0 },
		'mFar': { value: 1000.0 },

	},

	vertexShader: [

		'varying float vViewZDepth;',

		'void main() {',

		'	#include <begin_vertex>',
		'	#include <project_vertex>',

		'	vViewZDepth = - mvPosition.z;',

		'}'

	].join( '\n' ),

	fragmentShader: [

		'uniform float mNear;',
		'uniform float mFar;',

		'varying float vViewZDepth;',

		'void main() {',

		'	float color = 1.0 - smoothstep( mNear, mFar, vViewZDepth );',
		'	gl_FragColor = vec4( vec3( color ), 1.0 );',

		'} '

	].join( '\n' )

};

export { BokehShader, BokehDepthShader };