var http;
try {
http = new XMLHttpRequest();
} catch(e) {
try {
http = new ActiveXObject("Msxml2.XMLHTTP");
}
catch(e) {
try {
http = new ActiveXObject("Microsoft.XMLHTTP");
}
catch (e) {
alert("Váš prohlížeč nepodporuje AJAX");
}
}
}

function id(id) {
    return document.getElementById(id);
    }

function ajax(type, data, result1, result2, result3) {
    id('ajax').style.visibility = 'visible';
    url = '/prepocty/'+type+'.php?'+data+'&ajax='+Math.random();
    http.open("GET", url, true);
    http.onreadystatechange=function() {
        if(http.readyState == 4) {
            response = http.responseText.split(/@/);
            if(result1) id(result1).innerHTML = response[0];
            if(result2) id(result2).innerHTML = response[1];
            if(result3) id(result3).innerHTML = response[2];
            id('ajax').style.visibility = 'hidden';
        }
    }
    http.send(null);
}

function update_bmi() {
    in_height = id('in_height').value;
    in_weight = id('in_weight').value;
    if(in_height && in_weight) {
        data = 'in_height='+in_height+'&in_weight='+in_weight;
        ajax('bmi', data, 'out_bmi');
    }
    else id('out_bmi').innerHTML = '';
}

function update_length() {
    in_length = id('in_length').value;
    in_unit = id('in_unit').value;
    out_unit = id('out_unit').value;
    if(in_length) {
        data = 'in_length='+in_length+'&in_unit='+in_unit+'&out_unit='+out_unit;
        ajax('delka', data, 'out_length');
    }
    else id('out_length').innerHTML = 'X';
}

function update_area() {
    in_area = id('in_area').value;
    in_unit = id('in_unit').value;
    out_unit = id('out_unit').value;
    if(in_area) {
        data = 'in_area='+in_area+'&in_unit='+in_unit+'&out_unit='+out_unit;
        ajax('plocha', data, 'out_area');
    }
    else id('out_area').innerHTML = 'X';
}

function update_volume() {
    in_volume = id('in_volume').value;
    in_unit = id('in_unit').value;
    out_unit = id('out_unit').value;
    if(in_volume) {
        data = 'in_volume='+in_volume+'&in_unit='+in_unit+'&out_unit='+out_unit;
        ajax('objem', data, 'out_volume');
    }
    else id('out_volume').innerHTML = 'X';
}

function update_weight() {
    in_weight = id('in_weight').value;
    in_unit = id('in_unit').value;
    out_unit = id('out_unit').value;
    if(in_weight) {
        data = 'in_weight='+in_weight+'&in_unit='+in_unit+'&out_unit='+out_unit;
        ajax('hmotnost', data, 'out_weight');
    }
    else id('out_weight').innerHTML = 'X';
}

function update_temp() {
    in_temp = id('in_temp').value;
    in_unit = id('in_unit').value;
    if(in_temp) {
        data = 'in_temp='+in_temp+'&in_unit='+in_unit;
        ajax('teplota', data, 'out_c', 'out_f', 'out_k');
    }
    else {
        id('out_c').innerHTML = '';
        id('out_f').innerHTML = '';
        id('out_k').innerHTML = '';
        }
}

function update_speed() {
    in_speed = id('in_speed').value;
    in_unit = id('in_unit').value;
    out_unit = id('out_unit').value;
    if(in_speed) {
        data = 'in_speed='+in_speed+'&in_unit='+in_unit+'&out_unit='+out_unit;
        ajax('rychlost', data, 'out_speed');
    }
    else id('out_speed').innerHTML = 'X';
}

function update_power() {
    in_power = id('in_power').value;
    in_unit = id('in_unit').value;
    out_unit = id('out_unit').value;
    if(in_power) {
        data = 'in_power='+in_power+'&in_unit='+in_unit+'&out_unit='+out_unit;
        ajax('vykon', data, 'out_power');
    }
    else id('out_power').innerHTML = 'X';
}

function update_press() {
    in_press = id('in_press').value;
    in_unit = id('in_unit').value;
    out_unit = id('out_unit').value;
    if(in_press) {
        data = 'in_press='+in_press+'&in_unit='+in_unit+'&out_unit='+out_unit;
        ajax('tlak', data, 'out_press');
    }
    else id('out_press').innerHTML = 'X';
}

function update_shoe() {
    in_shoe = id('in_shoe').value;
    in_unit = id('in_unit').value;
    if(in_shoe) {
        data = 'in_shoe='+in_shoe+'&in_unit='+in_unit;
        ajax('boty', data, 'out_all');
    }
    else id('out_all').innerHTML = '';
}

function update_currency() {
    in_money = id('in_money').value;
    in_currency = id('in_currency').value;
    out_currency = id('out_currency').value;
    if(in_money) {
        data = 'in_money='+in_money+'&in_currency='+in_currency+'&out_currency='+out_currency;
        ajax('meny', data, 'out_money');
    }
    else id('out_money').innerHTML = 'X';
}