// NextXus Federation — Cognitive Circuitry License
// Animation: The Atmospheric Nebula
// License: Token Bundle (https://keywebster.gumroad.com/l/olhsf)
// Own the marrow.

    (function () {
        "use strict";
        var canvas = document.getElementById("canvas-kappa");
        var ctx = canvas.getContext("2d");
        var stage = canvas.parentElement;
        var reduced = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
        var PARTICLE_COUNT_MULT = 5, SIZE_MULT = 3, SPEED = 25, CONNECTION_DENSITY = 12, LINE_WIDTH = 0.8;
        var CYAN = "#00D4FF", GOLD = "#f4b942";
        var particles = [], connectionsOn = false, running = false, rafId = null;
        function resize() { canvas.width = stage.clientWidth; canvas.height = stage.clientHeight; }
        function connectDist() { return CONNECTION_DENSITY * 10; }
        function seed() {
            var count = Math.floor((canvas.width * canvas.height) / 25000 * PARTICLE_COUNT_MULT);
            particles = [];
            for (var i = 0; i < count; i++) {
                particles.push({
                    x: Math.random() * canvas.width,
                    y: Math.random() * canvas.height,
                    vx: (Math.random() - 0.5) * (SPEED / 30),
                    vy: (Math.random() - 0.5) * (SPEED / 30),
                    r: (0.5 + Math.random()) * SIZE_MULT,
                    color: Math.random() < 0.5 ? CYAN : GOLD
                });
            }
        }
        function connect() {
            if (!connectionsOn) return;
            var dist = connectDist();
            for (var i = 0; i < particles.length; i++) {
                for (var j = i + 1; j < particles.length; j++) {
                    var dx = particles[i].x - particles[j].x;
                    var dy = particles[i].y - particles[j].y;
                    var d = Math.sqrt(dx * dx + dy * dy);
                    if (d < dist) {
                        ctx.strokeStyle = particles[i].color;
                        ctx.globalAlpha = (1 - d / dist) * 0.5;
                        ctx.lineWidth = LINE_WIDTH;
                        ctx.beginPath();
                        ctx.moveTo(particles[i].x, particles[i].y);
                        ctx.lineTo(particles[j].x, particles[j].y);
                        ctx.stroke();
                    }
                }
            }
            ctx.globalAlpha = 1;
        }
        function draw() {
            ctx.clearRect(0, 0, canvas.width, canvas.height);
            connect();
            for (var i = 0; i < particles.length; i++) {
                var p = particles[i];
                ctx.fillStyle = p.color;
                ctx.beginPath();
                ctx.arc(p.x, p.y, p.r, 0, Math.PI * 2);
                ctx.fill();
            }
        }
        function step() {
            for (var i = 0; i < particles.length; i++) {
                var p = particles[i];
                p.x += p.vx; p.y += p.vy;
                if (p.x < 0 || p.x > canvas.width) { p.vx *= -1; p.x = Math.max(0, Math.min(canvas.width, p.x)); }
                if (p.y < 0 || p.y > canvas.height) { p.vy *= -1; p.y = Math.max(0, Math.min(canvas.height, p.y)); }
            }
        }
        function loop() { if (!running) return; step(); draw(); rafId = requestAnimationFrame(loop); }
        function start() { if (running || reduced) return; running = true; rafId = requestAnimationFrame(loop); }
        function stop() { running = false; if (rafId) cancelAnimationFrame(rafId); }
        var btnDrift = document.getElementById("kappa-btn-drift");
        var btnWeb = document.getElementById("kappa-btn-web");
        function setMode(web) {
            connectionsOn = web;
            btnDrift.classList.toggle("kappa-btn--active", !web);
            btnWeb.classList.toggle("kappa-btn--active", web);
            btnDrift.setAttribute("aria-pressed", String(!web));
            btnWeb.setAttribute("aria-pressed", String(web));
            if (reduced) draw();
        }
        btnDrift.addEventListener("click", function () { setMode(false); });
        btnWeb.addEventListener("click", function () { setMode(true); });
        window.addEventListener("resize", function () { resize(); seed(); draw(); });
        resize(); seed(); draw();
        if (!reduced) {
            if ("IntersectionObserver" in window) {
                new IntersectionObserver(function (entries) {
                    entries.forEach(function (e) { if (e.isIntersecting) start(); else stop(); });
                }).observe(canvas);
            } else { start(); }
        }
    })();