//
// Save page handler...   Handles CTRL+S keystroke press
//
//   Usage example :
//
//   var n = new SaveHandler();
//   n.addSaveHandler(function() {
//       alert("Before save");
//   });
//
//   n.addSaveHandler(getElementById("submit_button_id"));
//
//   n.addSaveHandler($("#submit_button_id")); // Multiplie object also pass via function call
//
//   @author : Eugene  (http://eugene.esy.es/works/programmer/js/jquery-save-handler)
//
function SaveHandler()
{
    if ( ! jQuery ) throw new Error("jQuery required for this class");
 
    var callptr   = 1;
    var domobject = 2;
    var jqueryobj = 3;
    var handlers = [];
 
    // Exports addSaveHandler function
    this.addSaveHandler = function(handler)
    {
        switch ( typeof(handler))
        {
            case "function" : handlers.push({ type: callptr, item: handler }); break;
            case "object"   : {
                // DOM Object
                if ( handler.hasOwnProperty('tagName')) {
                    handlers.push({ type: domobject, item: handler });
                    break;
                }
                // jQuery object
                if (( handler instanceof jQuery ) && ( !! handler.has("*").length )) {
                    handlers.push({ type: jqueryobj, item: handler });
                    break;
                }
            }
            default : console.error("Unsupported type of handler - supported only callback, dom object or jQuery object");
        }
    }
 
    // Connect to Window add base handler
    $(window).bind('keydown', function(event) {
        if ( event.ctrlKey || event.metaKey ) {
            switch ( String.fromCharCode(event.which).toLowerCase())
            {
                case 's' : { // CTRL+S
                    for ( var i=0 ; i<handlers.length ; i++ ) {
                        switch ( handlers[i].type ) {
                            case callptr : $i.item.call(this);
                            case domobject : $(handlers[i].item).click();
                            case jqueryobj : handlers[i].item.click();
                        }
                    }
                    event.preventDefault();
                    return false;
                }
            }
        }
        return true;
    });
 
}