<html>
    <head>
        <title>WebSocket Echo Client</title>
    </head>
    <body>
        <h1>WebSocket Echo Client</h1>
        <p>
            <button onClick="initWebSocket();">Connect</button>
            <button onClick="stopWebSocket();">Disconnect</button>
            <button onClick="checkSocket();">State</button>
        </p>
        <p>
            <textarea id="debugTextArea" style="width:400px;height:200px;"></textarea>
        </p>
        <p>
            <input type="text" id="inputText" onkeydown="if(event.keyCode==13)sendMessage();"/>
            <button onClick="sendMessage();">Send</button>
        </p>

        <script type="text/javascript">
            var debugTextArea = document.getElementById("debugTextArea");
            function debug(message) {
                debugTextArea.value += message + "\n";
                debugTextArea.scrollTop = debugTextArea.scrollHeight;
            }

            function sendMessage() {
                var msg = document.getElementById("inputText").value;
                if ( websocket != null )
                {
                    document.getElementById("inputText").value = "";
                    websocket.send( msg );
                    console.log( "string sent :", '"'+msg+'"' );
                }
            }

            var wsUri = "ws://localhost:1234";
            var websocket = null;

            function initWebSocket() {
                try {
                    if (typeof MozWebSocket == 'function')
                        WebSocket = MozWebSocket;
                    if ( websocket && websocket.readyState == 1 )
                        websocket.close();
                    websocket = new WebSocket( wsUri );
                    websocket.onopen = function (evt) {
                        debug("CONNECTED");
                    };
                    websocket.onclose = function (evt) {
                        debug("DISCONNECTED");
                    };
                    websocket.onmessage = function (evt) {
                        console.log( "Message received :", evt.data );
                        debug( evt.data );
                    };
                    websocket.onerror = function (evt) {
                        debug('ERROR: ' + evt.data);
                    };
                } catch (exception) {
                    debug('ERROR: ' + exception);
                }
            }

            function stopWebSocket() {
                if (websocket)
                    websocket.close();
            }

            function checkSocket() {
                if (websocket != null) {
                    var stateStr;
                    switch (websocket.readyState) {
                        case 0: {
                            stateStr = "CONNECTING";
                            break;
                        }
                        case 1: {
                            stateStr = "OPEN";
                            break;
                        }
                        case 2: {
                            stateStr = "CLOSING";
                            break;
                        }
                        case 3: {
                            stateStr = "CLOSED";
                            break;
                        }
                        default: {
                            stateStr = "UNKNOW";
                            break;
                        }
                    }
                    debug("WebSocket state = " + websocket.readyState + " ( " + stateStr + " )");
                } else {
                    debug("WebSocket is null");
                }
            }
        </script>
    </body>
</html>