// Das HUD ist reine Anzeige - es sendet nichts zurueck an den Client.
// Der Lua-Client schickt den kompletten Zustand samt Skalenendwerten, damit die
// Locale-Texte und die Config an einer Stelle bleiben.

const RING = 327; // 2 * PI * 52, muss zu --ring in style.css passen

// Zeigerinstrument: 270-Grad-Skala, unten offen - wie ein echtes Finimeter.
const DIAL_START = -135;
const DIAL_SWEEP = 270;
const DIAL_R = 42;

const hud = document.getElementById('hud');

// Das HUD ist auf 1080p entworfen. Ohne Nachskalieren waere es auf 1440p und 4K
// deutlich zu klein, weil FiveM das NUI in der echten Bildschirmaufloesung
// rendert. Der Faktor aus der Config kommt obendrauf.
const DESIGN_HEIGHT = 1080;
let configScale = 1;

function applyScale() {
    const scale = Math.min(2.5, Math.max(0.6, (window.innerHeight / DESIGN_HEIGHT) * configScale));
    document.documentElement.style.setProperty('--hud-scale', scale.toFixed(3));
}

applyScale();
window.addEventListener('resize', applyScale);
const gaugeFill = document.getElementById('gauge-fill');
const airValue = document.getElementById('air-value');
const lamp = document.getElementById('lamp');

const dials = {
    pressure: {
        needle: document.getElementById('pressure-needle'),
        zone: document.getElementById('pressure-zone'),
        ticks: document.getElementById('pressure-ticks'),
        value: document.getElementById('pressure-value')
    },
    depth: {
        needle: document.getElementById('depth-needle'),
        zone: document.getElementById('depth-zone'),
        ticks: document.getElementById('depth-ticks'),
        value: document.getElementById('depth-value')
    }
};

const labels = {
    air: document.getElementById('air-label'),
    depth: document.getElementById('depth-label'),
    pressure: document.getElementById('pressure-label'),
    lamp: document.getElementById('lamp-label')
};

const NS = 'http://www.w3.org/2000/svg';

const toRad = (deg) => ((deg - 90) * Math.PI) / 180;

function pointOn(radius, deg) {
    const r = toRad(deg);
    return [50 + radius * Math.cos(r), 50 + radius * Math.sin(r)];
}

/** Winkel für einen Messwert auf der Skala. */
function angleFor(value, max) {
    const ratio = Math.min(1, Math.max(0, value / (max || 1)));
    return DIAL_START + DIAL_SWEEP * ratio;
}

/** Striche einmalig zeichnen - die ändern sich nie. */
function buildTicks(group) {
    for (let i = 0; i <= 10; i++) {
        const deg = DIAL_START + (DIAL_SWEEP * i) / 10;
        const major = i % 2 === 0;
        const [x1, y1] = pointOn(DIAL_R - 6, deg);
        const [x2, y2] = pointOn(major ? DIAL_R - 13 : DIAL_R - 10, deg);
        const line = document.createElementNS(NS, 'line');

        line.setAttribute('x1', x1.toFixed(2));
        line.setAttribute('y1', y1.toFixed(2));
        line.setAttribute('x2', x2.toFixed(2));
        line.setAttribute('y2', y2.toFixed(2));

        if (major) line.setAttribute('class', 'major');

        group.appendChild(line);
    }
}

buildTicks(dials.pressure.ticks);
buildTicks(dials.depth.ticks);

/** Roter Bereich. Beim Finimeter die Reserve, beim Tiefenmesser die Grenze des Atemgases. */
function setZone(dial, from, to, max) {
    if (!(max > 0) || from === undefined || from >= max) {
        dial.zone.removeAttribute('d');
        return;
    }

    const a = angleFor(from, max);
    const b = angleFor(Math.min(to, max), max);
    const [x1, y1] = pointOn(DIAL_R - 2, a);
    const [x2, y2] = pointOn(DIAL_R - 2, b);
    const large = b - a > 180 ? 1 : 0;

    dial.zone.setAttribute(
        'd',
        `M ${x1.toFixed(2)} ${y1.toFixed(2)} A ${DIAL_R - 2} ${DIAL_R - 2} 0 ${large} 1 ${x2.toFixed(2)} ${y2.toFixed(2)}`
    );
}

function setNeedle(dial, value, max) {
    dial.needle.setAttribute('transform', `rotate(${angleFor(value, max).toFixed(2)} 50 50)`);
}

function formatTime(seconds) {
    const total = Math.max(0, Math.floor(seconds));
    const mm = String(Math.floor(total / 60)).padStart(2, '0');
    const ss = String(total % 60).padStart(2, '0');
    return `${mm}:${ss}`;
}

function render(state) {
    hud.classList.toggle('hidden', !state.visible);

    if (!state.visible) return;

    const capacity = state.capacity > 0 ? state.capacity : 1;
    const ratio = Math.min(1, Math.max(0, state.oxygen / capacity));

    gaugeFill.style.strokeDashoffset = String(RING * (1 - ratio));
    airValue.textContent = formatTime(state.oxygen);

    // Warnstufen kommen als Restsekunden vom Client, damit sie zu
    // config.warnAtSeconds passen statt hier nochmal definiert zu werden.
    hud.classList.toggle('warn', state.level === 'warn');
    hud.classList.toggle('danger', state.level === 'danger');
    hud.classList.toggle('overlimit', !!state.overLimit);

    const maxPressure = state.maxPressure || 300;
    dials.pressure.value.textContent = String(Math.round(state.pressure ?? 0));
    setNeedle(dials.pressure, state.pressure ?? 0, maxPressure);
    setZone(dials.pressure, 0, state.reservePressure ?? 0, maxPressure);
    hud.classList.toggle('pressure-alert', !!state.reserve);

    const depthScale = state.depthScale || 100;
    dials.depth.value.textContent = state.depth.toFixed(1);
    setNeedle(dials.depth, state.depth, depthScale);
    setZone(dials.depth, state.depthLimit, depthScale, depthScale);
    hud.classList.toggle('depth-alert', !!state.overLimit);
    hud.classList.toggle('depth-deep', !state.overLimit && !!state.deep);

    lamp.classList.toggle('hidden', !state.hasLamp);
    lamp.classList.toggle('on', !!state.lamp);
}

window.addEventListener('message', (event) => {
    const data = event.data;

    if (!data) return;

    if (data.action === 'labels') {
        if (typeof data.scale === 'number' && data.scale !== configScale) {
            configScale = data.scale;
            applyScale();
        }

        labels.air.textContent = data.air;
        labels.depth.textContent = data.depth;
        labels.pressure.textContent = data.pressure;
        labels.lamp.textContent = data.lamp;
        return;
    }

    if (data.action === 'state') render(data);
});

// Damit sich das HUD im Browser ohne FiveM anschauen laesst.
if (typeof GetParentResourceName !== 'function') {
    render({
        visible: true, oxygen: 372, capacity: 600,
        depth: 27.5, depthScale: 100, depthLimit: 45, deep: true,
        pressure: 186, maxPressure: 300, reservePressure: 50,
        level: 'ok', hasLamp: true, lamp: true
    });
}