// radio and checkbox
var i_names = ["how", "service_usage", "region[]", "sms_amount",
               "di_type[]", "detail_settings", "splitted", "difficulty[]",
               "drive_often", "drive_km"];

var i_ids_check_n = ["how", "region", "di_type", "difficulty"];
var i_ids_check_v = ["jiným způsobem", "J", "j", "j"];


function addmsg(msg) {
    var msgs = document.getElementById('messages');
    msgs.style.display = 'block';
    msgs.innerHTML += msg+"<br />\n";
}

function clearmsg() {
    var msgs = document.getElementById('messages');
    msgs.innerHTML = "<b>Vyplňte prosím rovněž otázky:</b><br />";
    msgs.style.display = 'none';
}

function convertQuestion(q) {
    if (q==8)
        return 9 + " a";
    if (q==9)
        return 9 + " b";
    return q+1;
}

function frm_submit(btn) {
    btn.disabled = true;
    btn.readonly = true;
    clearmsg();

    var frm      = document.getElementById('frm');
    var i        = 0;
    var e        = 0;
    var checkedgrp = [];
    var canSend    = true;

    for (i=0; i<i_names.length; i++) {
        checkedgrp[i] = false;
        for (e=0; e<frm.elements[i_names[i]].length; e++) {
            var elem = frm.elements[i_names[i]].item(e);
            var ic=0;
            checkedgrp[i] = checkedgrp[i] || elem.checked;

                for (ic=0; ic<i_ids_check_n.length; ic++) {
                    // i_ids_check_v
                    if (elem.id!=undefined && elem.id.match(i_ids_check_n[ic]) && elem.checked && i_ids_check_v[ic]==elem.value) {
                       var elem_txt = document.getElementById(elem.id+'_text');
                       if (elem_txt!=undefined && (elem_txt.value==undefined || elem_txt.value.length==0 )) {
                           canSend = false;
                           addmsg(convertQuestion(i)+") prosím doplňte text");
                       }
                    }
                }

        }
    }


    for (i=0; i<checkedgrp.length; i++) {
        if (!checkedgrp[i]) {
            addmsg(convertQuestion(i)+")");
            canSend = false;
        }
    }

    var email = document.getElementById('email');
    if (email.value==undefined || !email.value.match("@")) {
        canSend = false;
        addmsg("Vyplňte prosím emailovou adresu.");
    }


    if (!canSend) {
        btn.disabled = false;
        btn.readonly = false;
        window.location='#messages';
    } else {
        frm.submit();
    }
}

function switchtxt(id) {
    var el = document.getElementById(id);
    var eltxt = document.getElementById(id+"_text");
    eltxt.readonly = !el.checked;
    eltxt.disabled = !el.checked;
}