function Common()
{
    return this;
}

Common.isNumberKey = function(event)
{
    var charCode = (event.which) ? event.which : event.keyCode
    return (!(charCode > 31 && (charCode < 48 || charCode > 57)));
}

Common.isFn = function(func)
{
    return ('function' == typeof func);
}

Common.isEnter = function(event)
{
    return event.keyCode == 13;
}

Common.price_with_cutrrency = function(price, currency)
{
    if (price <= 0) return '-';
    
    switch (currency) {
        case 1:
            return price + ' грн.';
            break;

        case 2:
            return '€ ' + price;
            break;

        case 3:
            return '$ ' + price;
            break;

        case 4:
            return price + ' р.';
            break;

        case 5:
            return price + ' бел. руб.';
            break;

        default:
            return price + ' грн.';
            break;
    }
}

Common.Coords2String = function(coords) {
    return coords[0] + ',' + coords[1];
}

Common.String2Coords = function(string) {
    var coords = string.split(',');
    coords[0] = parseFloat(coords[0]);
    coords[1] = parseFloat(coords[1]);
    
    return coords;
}

Common.post = function(url, data, callback) {
    Common.request(url, data, callback, 'POST');
}

Common.get = function(url, data, callback) {
    Common.request(url, data, callback, 'GET');
}

Common.request = function(url, data, callback, method) {
    $.ajax({
            type: method,
            url: url,
            data: data,
            success: function(data) {
                callback(data);
            },
            error: function(xhr, status, errorThrown) {
            },
            dataType: 'json'
    });
}