// 'keyb_change' and 'keyb_callback' functions
   // do all the job here.

	var is_opened = false, vkb = null, text = null;

	function keyb_change() {
		document.getElementById("switch").innerHTML = (is_opened ? "Show national characters" : "Hide national characters");
		is_opened = !is_opened;

		if(is_opened && !vkb) {
			// Note: all parameters, starting with 3rd, in the following
			// expression are equal to the default parameters for the
			// VKeyboard object. The only exception is 15th parameter
			// (flash switch), which is false by default.
	
			vkb = new VKeyboard(
				"keyboard",		// container's id
				keyb_callback,	// reference to the callback function
				false,			// create the arrow keys or not? (this and the following params are optional)
				false,			// create up and down arrow keys? 
				false,			// reserved
				true,			// create the numpad or not?
				"",				// font name ("" == system default)
				"14px",			// font size in px
				"#000",			// font color
				"#F00",			// font color for the dead keys
				"#FFF",			// keyboard base background color
				"#FFF",			// keys' background color
				"#DDD",			// background color of switched/selected item
				"#777",			// border color
				"#CCC",			// border/font color of "inactive" key (key with no value/disabled)
				"#FFF",			// background color of "inactive" key (key with no value/disabled)
				"#F77",			// border color of the language selector's cell
				true,			// show key flash on click? (false by default)
				"#CC3300",		// font color during flash
				"#FF9966",		// key background color during flash
				"#CC3300",		// key border color during flash
				false,			// embed VKeyboard into the page?
				true,			// use 1-pixel gap between the keys?
				0);				// index(0-based) of the initial layout
		}
		else {
			vkb.Show(is_opened);
		}
		var selcted_lan = document.getElementById('from_lang').value;
		if(selcted_lan.length == 0 || selcted_lan == "En") {
			selcted_lan = "Us"
		}
		vkb._refresh_layout(selcted_lan);
		text = document.getElementById("text_for_translation");
		text.focus();
		if(document.attachEvent) text.attachEvent("onblur", backFocus);
	}

	function backFocus() {
		if(is_opened) {
			var l = text.value.length;
			setRange(text, l, l);
			//text.focus();
		}
	}

	// Callback function:
	function keyb_callback(ch) {
		var val = text.value;
		switch(ch) {
			case "BackSpace":
				var min = (val.charCodeAt(val.length - 1) == 10) ? 2 : 1;
				text.value = val.substr(0, val.length - min);
			break;
			case "Enter":
				text.value += "\n";
			break;
			default:
				text.value += ch;
		}
	}

	function setRange(ctrl, start, end) {
		if(ctrl.setSelectionRange) {// Standard way (Mozilla, Opera, ...)
			ctrl.setSelectionRange(start, end);
		}
		else { // MS IE
			var range;
			try {
				range = ctrl.createTextRange();
			}
			catch(e) {
				try {
					range = document.body.createTextRange();
					range.moveToElementText(ctrl);
				}
				catch(e) {
					range = null;
				}
			}
			if(!range) return;
			
			range.collapse(true);
			range.moveStart("character", start);
			range.moveEnd("character", end - start);
			range.select();
		}
	}