#define PI 3.14159
#define TAU 6.28319

#define WIDTH 3.
#define RADIUS 1.

#define WIPE_DURATION .2
#define BORDER_LOOPS 3.
#define FADE_ITS 2.

vec4 gradi(float pos, vec4 bg, vec4 fg, float fac, float mask) {
    if (mask < 0.2) {
    	return bg;
    }

	vec4 trans = vec4(0.);
    vec4 purple = vec4(0.45, 0.13, 0.49, 1.0) * vec4(mask);
    vec4 blue = vec4(0.25, 0.74, 0.81, 1.0) * vec4(mask);
    vec4 white = vec4(mask);
    float mult = 4. * fac;

	if (pos <= 0.125) {
		return mix(bg, purple, max(0., pos * mult));
	} else if (pos <= 0.25) {
		return mix(purple, blue, (pos * mult) - 1.);
	} else if (pos <= 0.5) {
		return mix(blue, white, (pos * mult) - 2.);
	} else {
		return fg;
	}
	
}

// from niri source code: https://github.com/YaLTeR/niri/blob/f30db163b5748e8cf95c05aba77d0d3736f40543/src/render_helpers/shaders/border.frag#L211-L234
float rounding_alpha(vec2 coords, vec2 size, vec4 corner_radius) {
    vec2 center;
    float radius;

    if (coords.x < corner_radius.x && coords.y < corner_radius.x) {
        radius = corner_radius.x;
        center = vec2(radius, radius);
    } else if (size.x - corner_radius.y < coords.x && coords.y < corner_radius.y) {
        radius = corner_radius.y;
        center = vec2(size.x - radius, radius);
    } else if (size.x - corner_radius.z < coords.x && size.y - corner_radius.z < coords.y) {
        radius = corner_radius.z;
        center = vec2(size.x - radius, size.y - radius);
    } else if (coords.x < corner_radius.w && size.y - corner_radius.w < coords.y) {
        radius = corner_radius.w;
        center = vec2(radius, size.y - radius);
    } else {
        return 1.0;//
    }

    float dist = distance(coords, center);
    float half_px = 0.5;
    return 1.0 - smoothstep(radius - half_px, radius + half_px, dist);
}

vec4 open_color(vec3 coords_geo, vec3 size_geo) {
    vec4 bg1 = vec4(.1, .1, .18, 1.0);
    vec4 bg2 = vec4(.09, .05, .11, 1.0);

    vec3 coords_tex = niri_geo_to_tex * coords_geo;
    vec4 color = texture2D(niri_tex, coords_tex.st);

    float pi = radians(180.);

    if (0.0 <= coords_geo.x && coords_geo.x <= 1.0
            && 0.0 <= coords_geo.y && coords_geo.y <= 1.0)
    {
        float pos = (coords_tex.x - ((1. / WIPE_DURATION) * niri_clamped_progress) * 2.) + 1.;
	    vec2 coords = (coords_geo.xy - vec2(0.5, 0.5)) * size_geo.xy * 2.0;
	    vec2 coords_abs = coords_geo.xy * size_geo.xy;

	    float border_a = 1.;

	    border_a *= rounding_alpha(
	    	coords_abs.xy,
	    	size_geo.xy,
	    	vec4(RADIUS + WIDTH)
	    );

        vec4 bg = mix(bg1, bg2, length(coords_tex.xy - vec2(1., 0.))) * border_a;

		color = gradi(pos, color, bg, 2.0, border_a);

	    float angle = (atan(coords.y, coords.x) + PI) / TAU;
	    float spinny_angle = mod((angle + niri_clamped_progress * BORDER_LOOPS), 1.0) / 2.;

	    vec2 border = WIDTH / size_geo.xy;

	    float temp = border_a;
	    float round_a = 1. - rounding_alpha(
	    	coords_abs.xy - WIDTH,
	    	size_geo.xy - WIDTH * 2.,
	    	vec4(RADIUS)
	    );

		if (coords_geo.x <= border.x || coords_geo.x >= (1. - border.x) ||
	     	coords_geo.y <= border.y || coords_geo.y >= (1. - border.y)) {
		    border_a *= round_a;
     	}

     	float rest = 0.;
     	if (border_a + temp == 1.)  {
     		rest = 1.;
     	}

	    border_a *= round_a;
	    border_a += rest;
		
	    vec4 grad = gradi(
	    	spinny_angle,
	    	vec4(.48, .37, .5, 1.),
	    	vec4(1., 0., 0., 1.),
	    	2.0, // DO NOT TOUCH
	    	border_a
	    );

	    if ((1. - niri_clamped_progress) < FADE_ITS / BORDER_LOOPS) {
	    	border_a *= (1. - niri_clamped_progress) / (FADE_ITS / BORDER_LOOPS);
	    }
	    color = mix(color, grad, border_a);

    }

    return color;
}