document.addEventListener('DOMContentLoaded', function () {
    calculatefcv();
    calculateflv();
    calculatefev();
    calculatefhv();
    calculatefcr();
    calculateflr();
    calculatefer();
    calculatefhr();
    calculatef();

});

function showTab(tabId) {
    document.querySelectorAll('.tab-content').forEach(tab => {
        tab.classList.remove('active');
    });

    document.querySelectorAll('.subtab-content').forEach(subtab => {
        subtab.classList.remove('active');
    });

    document.querySelectorAll('.subsubtab-content').forEach(subsubtab => {
        subsubtab.classList.remove('active');
    });

    const activeTab = document.getElementById(tabId);
    activeTab.classList.add('active');

    document.querySelectorAll('.tab').forEach(tab => {
        tab.classList.remove('active');
    });
    const activeTabElement = document.querySelector(`.tab[onclick*="${tabId}"]`);
    if (activeTabElement) {
        activeTabElement.classList.add('active');
    }

    const firstSubtab = activeTab.querySelector('.subtab-content');
    if (firstSubtab) {
        firstSubtab.classList.add('active');
        const firstSubsubtab = firstSubtab.querySelector('.subsubtab-content');
        if (firstSubsubtab) {
            firstSubsubtab.classList.add('active');
        }
    }
}

function showSubTab(subTabId) {
    document.querySelectorAll('.tab-content.active .subtab-content').forEach(subtab => {
        subtab.classList.remove('active');
    });

    const subtabToShow = document.getElementById(subTabId);
    subtabToShow.classList.add('active');

    document.querySelectorAll('.subtab').forEach(subtab => {
        subtab.classList.remove('active');
    });
    const activeSubtabElement = document.querySelector(`.subtab[onclick*="${subTabId}"]`);
    if (activeSubtabElement) {
        activeSubtabElement.classList.add('active');
    }

    const firstSubsubtab = subtabToShow.querySelector('.subsubtab-content');
    if (firstSubsubtab) {
        firstSubsubtab.classList.add('active');
    }
}

function showSubSubTab(subSubTabId) {
    document.querySelectorAll('.subtab-content.active .subsubtab-content').forEach(subsubtab => {
        subsubtab.classList.remove('active');
    });

    const subsubtabToShow = document.getElementById(subSubTabId);
    subsubtabToShow.classList.add('active');

    document.querySelectorAll('.subsubtab').forEach(subsubtab => {
        subsubtab.classList.remove('active');
    });
    const activeSubsubtabElement = document.querySelector(`.subsubtab[onclick*="${subSubTabId}"]`);
    if (activeSubsubtabElement) {
        activeSubsubtabElement.classList.add('active');
    }
}

function calculatefcv() {
    const r = parseFloat(document.getElementById('radiusfcv').value);
    const e = parseFloat(document.getElementById('superelevationfcv').value);
    const f = parseFloat(document.getElementById('frictionfcv').value);

    const v = Math.sqrt(127 * r * (e + f));

    document.getElementById('resultfcvBE').innerText = v.toFixed(0);
}

function calculateflv() {
    const r = parseFloat(document.getElementById('radiusflv').value);
    const e = parseFloat(document.getElementById('superelevationflv').value);
    const fo = parseFloat(document.getElementById('floflv').value);
    const b = parseFloat(document.getElementById('betaflv').value);

    let v = 0;
    let previousV = -1;

    while (Math.abs(v - previousV) > 0.0001) {
        previousV = v;
        v = Math.sqrt(127 * r * (e + (fo - b * v)));
    }

    const f = fo - b * v;


    document.getElementById('frictionflv').innerText = f.toFixed(2);
    document.getElementById('resultflvBE').innerText = v.toFixed(0);
}

function calculatefev() {
    const r = parseFloat(document.getElementById('radiusfev').value);
    const e = parseFloat(document.getElementById('superelevationfev').value);
    const fo = parseFloat(document.getElementById('flofev').value);
    const b = parseFloat(document.getElementById('betafev').value);

    let v = 0;
    let previousV = -1;

    while (Math.abs(v - previousV) > 0.0001) {
        previousV = v;
        v = Math.sqrt(127 * r * (e + fo * Math.exp(-b * v)));
    }

    const f = fo * Math.exp(-b * v);


    document.getElementById('frictionfev').innerText = f.toFixed(2);
    document.getElementById('resultfevBE').innerText = v.toFixed(0);
}

function calculatefhv() {
    const r = parseFloat(document.getElementById('radiusfhv').value);
    const e = parseFloat(document.getElementById('superelevationfhv').value);
    const bpn = parseFloat(document.getElementById('bpnfhv').value);
    const sp = parseFloat(document.getElementById('spfhv').value);

    const sno = -31 + (1.38 * bpn);
    const pnfsg = 0.45 * Math.pow(sp, -0.47);

    let v = 0;
    let previousV = -1;

    while (Math.abs(v - previousV) > 0.0001) {
        previousV = v;
        const f = 0.01 * sno * Math.exp(-(pnfsg / 100) * v);
        v = Math.sqrt(127 * r * (e + f));
    }

    const f = 0.01 * sno * Math.exp(-(pnfsg / 100) * v);


    document.getElementById('frictionfhv').innerText = f.toFixed(2);
    document.getElementById('resultfhvBE').innerText = v.toFixed(0);
}

function calculatefcr() {
    const v = parseFloat(document.getElementById('speedfcr').value);
    const e = parseFloat(document.getElementById('superelevationfcr').value);
    const f = parseFloat(document.getElementById('frictionfcr').value);

    const r = (v * v) / (127 * (e + f));

    document.getElementById('resultfcrBE').innerText = r.toFixed(0);
}

function calculateflr() {
    const v = parseFloat(document.getElementById('speedflr').value);
    const e = parseFloat(document.getElementById('superelevationflr').value);
    const fo = parseFloat(document.getElementById('floflr').value);
    const b = parseFloat(document.getElementById('betaflr').value);

    const f = fo - b * v;
    const r = v ** 2 / (127 * (e + f));


    document.getElementById('frictionflr').innerText = f.toFixed(2);
    document.getElementById('resultflrBE').innerText = r.toFixed(0);
}

function calculatefer() {
    const v = parseFloat(document.getElementById('speedfer').value);
    const e = parseFloat(document.getElementById('superelevationfer').value);
    const fo = parseFloat(document.getElementById('flofer').value);
    const b = parseFloat(document.getElementById('betafer').value);

    const f = fo * Math.exp(-b * v);
    const r = v ** 2 / (127 * (e + f));

    document.getElementById('frictionfer').innerText = f.toFixed(2);
    document.getElementById('resultferBE').innerText = r.toFixed(0);
}

function calculatefhr() {
    const v = parseFloat(document.getElementById('speedfhr').value);
    const e = parseFloat(document.getElementById('superelevationfhr').value);
    const bpn = parseFloat(document.getElementById('bpnfhr').value);
    const sp = parseFloat(document.getElementById('spfhr').value);

    const sno = -31 + (1.38 * bpn);
    const pnfsg = 0.45 * Math.pow(sp, -0.47);
    const f = 0.01 * sno * Math.exp(-(pnfsg / 100) * v);

    const r = v ** 2 / (127 * (e + f));

    document.getElementById('frictionfhr').innerText = f.toFixed(2);
    document.getElementById('resultfhrBE').innerText = r.toFixed(0);
}

function calculatef() {
    const v = parseFloat(document.getElementById('speedf').value);
    const e = parseFloat(document.getElementById('superelevationf').value);
    const r = parseFloat(document.getElementById('radiusf').value);

    const f = (v ** 2 / (127 * r)) - e;

    document.getElementById('resultfBE').innerText = f.toFixed(2);
}