//Event Handler + other global variables
var bindEvt = (function () {
    "use strict";
    if (document.addEventListener) {
        return function (element, event, handler) {
            element.addEventListener(event, handler, false);
        };
    }
    return function (element, event, handler) {
        element.attachEvent('on' + event, handler);
    };
}()),
timeset,
countdown,
start,
pause,
reset;

//Convert seconds to time
function dhms(s, f) {
    var d = h = m = 0;
    switch (true) {
        case (s > 86400):
            d = Math.floor(s / 86400);
            s -= d * 86400;
        case (s > 3600):
            h = Math.floor(s / 3600);
            s -= h * 3600;
        case (s > 60):
            m = Math.floor(s / 60);
            s -= m * 60;
    }
    if (f != null) {
        var f = f.replace('dd', (d < 10) ? "0" + d : d);
        f = f.replace('d', d);
        f = f.replace('hh', (h < 10) ? "0" + h : h);
        f = f.replace('h', h);
        f = f.replace('mm', (m < 10) ? "0" + m : m);
        f = f.replace('m', m);
        f = f.replace('ss', (s < 10) ? "0" + s : s);
        f = f.replace('s', s);
    }
    else {
        f = d + ':' + h + ':' + m + ':' + s;
    }
    return f;
}



//set timer
function starttimer() {
    if (timeset == null) { timeset = document.getElementById('timerange').value * 60; };
    function startcounting() {
        document.getElementById('fulltime').innerHTML = dhms(timeset, 'hh:mm:ss');
        timeset -= 1;
    }
    startcounting();
    countdown = setInterval(startcounting, 1000);

}
function pausetimer() {
    window.clearInterval(countdown)
}

function resettimer() {
    window.clearInterval(countdown)
    timeset = null;
    document.getElementById('fulltime').innerHTML = "";
}

//detect interactions
function runtimer() {
    start = document.getElementById('start');
    pause = document.getElementById('pause');
    reset = document.getElementById('reset');
    bindEvt(start, "click", starttimer);
    bindEvt(pause, "click", pausetimer);
    bindEvt(reset, "click", resettimer);
}

//onload event
bindEvt(window, "load", runtimer);