#version 450 core

#pragma include ./shared.glsl
#pragma include ../misc/camera.glsl

in FragmentData fragmentData;

layout (location = 1) uniform vec2 uRings;
layout (location = 2) uniform vec2 uMarker;
layout (location = 3) uniform vec4 uValue;
layout (location = 4) uniform float uProgress;
layout (location = 5) uniform float uSize;

out vec4 outColor;

#pragma include ./shared_frag.glsl

/**
 * Calculate the splitter animation
 *
 * @param t     Animation process in range [0.0, 1.0]
 * @param r     Radius of the current fragment
 *
 * @return      The animation value of splitters
 */
float calcSplitterAnimation(float t, float r) {
    return smoothstep2(
        animLinear(1.1 * uRings[0], (uRings[0] - 0.05), t),
        animLinear(1.1 * uRings[0],  uRings[0],         t),
        animLinear(1.1 * uRings[0],  uRings[1],         t),
        animLinear(1.1 * uRings[0], (uRings[1] + 0.05), t),
        r);
}

/**
 * Calculate the value of a splitter
 *
 * @param pi    Position of the splitter as multiple of PI / 4
 * @param anim  Animation value calculated by 'calcSplitterAnimation'
 * @param a     Angle of the current fragment
 * @param r     Radius of the current fragment
 * @param zoom  Current zoom factor
 *
 * @return      Splitter value.
 */
float calcSplitter(float pi, float anim, float a, float r, float zoom) {
    return anim * calcLine(a, pi * PI / 4.0, MARKER_STRENGTH / r / zoom, MARKER_BLUR / r / zoom);
}

/**
 * Calculate the value of a ring that represents a given ship count value
 *
 * @param pi0   Position to start the value ring at as multiple of PI / 4
 * @param pi1   Position to end the value ring at as multiple of PI / 4
 * @param angle Angle of the current fragment
 * @param t     Animation process in range [0.0, 1.0]
 * @param anim  Animation value calculated by 'calcSplitterAnimation'
 * @param value Actual value of the ring
 * @param r     Radius of the current fragment
 * @param zoom  Current zoom factor
 *
 * @return      Value of the value ring
 */
float calcValueRing(float pi0, float pi1, float angle, float t, float anim, float value, float r, float zoom) {
    float x = animLinear(uRings[0], uRings[1], value);
    x = anim * calcLine(r, animEaseInOutQuadric(uSize, x, t), RING_STRENGTH / zoom, RING_BLUR / zoom);

    if (pi0 < pi1) {
        x *= step(  pi0 * PI / 4.0, angle) * step(angle,   pi1 * PI / 4.0);
    } else {
        x *= step(  pi0 * PI / 4.0, angle) + step(angle,   pi1 * PI / 4.0);
    }

    return x;
}

void main() {
    /* setup */
    float t_opn     = clamp(uProgress, 0.0, 1.0);
    float t_cls     = clamp(uProgress - 1.0, 0.0, 1.0);
    float r         = length(fragmentData.texCoords);
    float zoom      = pow(length(uCamera.view[0].xyz), 0.5);
    float angle     = calcAngle(fragmentData.texCoords, VEC_HORZ);

    /* marker */
    float m         = calcMarker(t_opn, angle, r, zoom);

    /* splitter */
    float x         = calcSplitterAnimation(t_opn, r);
    float s0        = 0.25 * calcSplitter( 3.0, x, angle, r, zoom);
    float s1        = 0.25 * calcSplitter( 1.0, x, angle, r, zoom);
    float s2        = 0.25 * calcSplitter(-1.0, x, angle, r, zoom);
    float s3        = 0.25 * calcSplitter(-3.0, x, angle, r, zoom);

    /* rings */
    float f         = calcRingsAnimation(t_opn, angle, 0.0);
    float t_opn_rad = clamp(2.0 * t_opn, 0.0, 1.0);
    float r0        = 0.25 * calcRing(t_opn_rad, f, uRings[0], r, zoom);
    float r1        = 0.25 * calcRing(t_opn_rad, f, uRings[1], r, zoom);

    float v0        = 0.75 * calcValueRing( 3.0, -3.0, angle, t_opn_rad, f, uValue[0], r, zoom);
    float v1        = 0.75 * calcValueRing( 1.0,  3.0, angle, t_opn_rad, f, uValue[1], r, zoom);
    float v2        = 0.75 * calcValueRing(-1.0,  1.0, angle, t_opn_rad, f, uValue[2], r, zoom);
    float v3        = 0.75 * calcValueRing(-3.0, -1.0, angle, t_opn_rad, f, uValue[3], r, zoom);

    /* alpha */
    float a         = calcAlpha(t_opn, t_cls);

    /* put together */
    vec3 rgb        = vec3(1.0);

    outColor        = vec4(rgb, (v0 + v1 + v2 + v3 + r0 + r1 + m + s0 + s1 + s2 + s3) * a + uSize * 0.0001);
}