const form = document.getElementById('af-calculator');
const weaponSelect = document.getElementById('af-weapon-select');
const outputs = {
    shotDamage: document.querySelector('[data-output="shotDamage"]'),
    burstDps: document.querySelector('[data-output="burstDps"]'),
    sustainedDps: document.querySelector('[data-output="sustainedDps"]'),
    timeToEmpty: document.querySelector('[data-output="timeToEmpty"]'),
    magDamage: document.querySelector('[data-output="magDamage"]'),
    ttk: document.querySelector('[data-output="ttk"]')
};

const resetButton = document.getElementById('af-reset');
const copyButton = document.getElementById('af-copy');
const weaponsById = new Map();

const numberOrNull = (value) => {
    const parsed = Number.parseFloat(value);
    return Number.isFinite(parsed) ? parsed : null;
};

const formatValue = (value, suffix = '') => {
    if (value === null) {
        return '--';
    }
    const formatted = Number.isFinite(value) ? value.toFixed(2) : '--';
    return `${formatted}${suffix}`;
};

const calculate = () => {
    const data = new FormData(form);
    const baseDamage = numberOrNull(data.get('baseDamage'));
    const projectiles = numberOrNull(data.get('projectiles')) ?? 1;
    const rpm = numberOrNull(data.get('rpm'));
    const magazine = numberOrNull(data.get('magazine'));
    const reload = numberOrNull(data.get('reload'));
    const targetHealth = numberOrNull(data.get('targetHealth'));

    if (!baseDamage || !rpm) {
        Object.values(outputs).forEach((node) => {
            node.textContent = '--';
        });
        return;
    }

    const shotDamage = baseDamage * projectiles;
    const shotsPerSecond = rpm / 60;
    const burstDps = shotDamage * shotsPerSecond;
    const magDamage = magazine ? shotDamage * magazine : null;
    const timeToEmpty = magazine ? magazine / shotsPerSecond : null;

    let sustainedDps = null;
    if (magDamage !== null && reload !== null && timeToEmpty !== null && (timeToEmpty + reload) > 0) {
        sustainedDps = magDamage / (timeToEmpty + reload);
    }

    let ttk = null;
    if (targetHealth && burstDps > 0) {
        ttk = targetHealth / burstDps;
    }

    outputs.shotDamage.textContent = formatValue(shotDamage);
    outputs.burstDps.textContent = formatValue(burstDps);
    outputs.sustainedDps.textContent = formatValue(sustainedDps);
    outputs.timeToEmpty.textContent = formatValue(timeToEmpty, 's');
    outputs.magDamage.textContent = formatValue(magDamage);
    outputs.ttk.textContent = formatValue(ttk, 's');
};

const setFormValue = (name, value) => {
    const field = form.elements[name];
    if (!field) {
        return;
    }
    field.value = value ?? '';
};

const applyWeapon = (weapon) => {
    if (!weapon) {
        return;
    }
    setFormValue('weaponName', weapon.name ?? '');
    setFormValue('baseDamage', weapon.damage ?? '');
    setFormValue('projectiles', weapon.damage_multiplier ?? 1);
    setFormValue('rpm', weapon.rpm ?? '');
    setFormValue('magazine', weapon.mag_size ?? '');
    setFormValue('reload', weapon.reload_time ?? '');
    calculate();
};

const loadWeaponLibrary = async () => {
    if (!weaponSelect) {
        return;
    }
    const source = weaponSelect.dataset.source;
    if (!source) {
        return;
    }

    try {
        const response = await fetch(source);
        if (!response.ok) {
            throw new Error('Failed to load weapons');
        }
        const weapons = await response.json();
        const normalized = weapons
            .filter((weapon) => weapon && weapon.name)
            .map((weapon) => ({
                id: weapon.id ?? weapon.name,
                name: weapon.name,
                damage: weapon.damage,
                damage_multiplier: weapon.damage_multiplier ?? 1,
                rpm: weapon.rpm,
                mag_size: weapon.mag_size,
                reload_time: weapon.reload_time
            }))
            .sort((a, b) => a.name.localeCompare(b.name));

        normalized.forEach((weapon) => {
            const key = String(weapon.id);
            weaponsById.set(key, weapon);
            const option = document.createElement('option');
            option.value = key;
            option.textContent = weapon.name;
            weaponSelect.appendChild(option);
        });
    } catch (error) {
        console.error('Weapon library load failed', error);
        const option = document.createElement('option');
        option.textContent = 'Weapon library unavailable';
        option.disabled = true;
        weaponSelect.appendChild(option);
    }
};

form.addEventListener('input', calculate);

resetButton.addEventListener('click', () => {
    form.reset();
    calculate();
});

if (weaponSelect) {
    weaponSelect.addEventListener('change', (event) => {
        const selected = weaponsById.get(event.target.value);
        if (!selected) {
            return;
        }
        applyWeapon(selected);
    });
}

copyButton.addEventListener('click', async () => {
    const data = new FormData(form);
    const name = data.get('weaponName') || 'Unnamed loadout';
    const payload = [
        `Loadout: ${name}`,
        `Damage per shot: ${outputs.shotDamage.textContent}`,
        `Burst DPS: ${outputs.burstDps.textContent}`,
        `Sustained DPS: ${outputs.sustainedDps.textContent}`,
        `Time to empty: ${outputs.timeToEmpty.textContent}`,
        `Magazine damage: ${outputs.magDamage.textContent}`,
        `Time to eliminate: ${outputs.ttk.textContent}`
    ].join('\n');

    try {
        await navigator.clipboard.writeText(payload);
        copyButton.textContent = 'Copied!';
        setTimeout(() => {
            copyButton.textContent = 'Copy summary';
        }, 2000);
    } catch (error) {
        console.error('Clipboard copy failed', error);
        copyButton.textContent = 'Copy failed';
        setTimeout(() => {
            copyButton.textContent = 'Copy summary';
        }, 2000);
    }
});

calculate();
loadWeaponLibrary();