$(document).ready(function()
{
	
	var char_fields = $('form.singlechars input.char');
	
	if(char_fields.length)
	{
		char_fields.each(function(key, value)
		{
			// focus first element
			if(key == 0) $(value).focus();
				
			$(value).keyup(function(e)
			{
				if(e.keyCode == 8)
				{
					var delete_previous = ($(value).attr("value") == "");
					
					$(value).attr("value", "");
					
					if(char_fields[key-1])
					{
						$(char_fields[key-1]).focus();
						
						if(delete_previous)
							$(char_fields[key-1]).attr("value", "");
					}
				}
				else if(e.keyCode != 9)
				{
					var entered_value = $(value).attr("value");
					
					if(entered_value != "" && entered_value != " ")
					{
						if(char_fields[key+1])
						{
							$(char_fields[key+1]).focus();	
							$(char_fields[key+1]).select();
						}
						else
						{
							$('#next_button').focus();
						}
					}
				}
			})
		})
		
	}
	

});