function getRndItem(field) {
    var index = Math.floor(field.length*Math.random())
    
    return field[index]; 
}

function getRandomIon() {
    return getRndItem(ionts);
}

function getRandomElement() {
    var index = Math.floor(elements.length*Math.random())
    
    return elements[index];
}

function getFormula(ion) {
    var out = ion.label + "<sup>" + ion.charge.replace("-","−") + "</sup>"
    return out;
}

function getValenceCount(element) {
    
    var valence = element.valence.trim();
    if (valence == "") return 0;
    var orbitals = valence.split(/\s+/);
    
    
    var count = 0;
    for (var i = 0; i < orbitals.length; i++) {
        var orbCount = parseInt(orbitals[i].substring(2), 10);
        
        count += orbCount;
    }
    
    return count;
}

function getFullCount(ion) {
    return getElCount(ion.full);
}

function getElCount(text) {
    var orbitals = text.trim().split(/\s+/);
    
    var count = 0;
    for (var i = 0; i < orbitals.length; i++) {
        var orbCount = parseInt(orbitals[i].substring(2), 10);
        
        count += orbCount;
    }
    
    return count;
}

function getFullConfig(ion) {
    return  getHTMLFull(ion)
}

function getHTMLValence(element) {
    return getHTMLElconfig(element.valence);
}

function getHTMLFull(element) {
    return getHTMLElconfig(element.full);
}

function getHTMLElconfig(text) {
    var orbitals = text.trim().split(/\s+/);
    
    var out = [];
    for (var i = 0; i < orbitals.length; i++) {
        out.push(orbitals[i].replace(/(\d[spdfg])(\d+)/g, "$1<sup>$2</sup>"));
    }
    return out.join(" ");
}