get online chat using angular

chat.php

<?php include('header.php') ?>

<div class="container">
    <div class="widget widget_volunteer_form">
        <div class="well" ng-app="chat" ng-controller="Chat">
            <?php if (isset($_SESSION['userid'])) {
            $uid = $_SESSION['userid'];
            $conQuerry = mysqli_query($conn, "Select * from Ccsbi_Users where UserId='$uid'");
            $row = mysqli_fetch_assoc($conQuerry);
            $fName = $row['fName'];
            ?>
            <form class="form-inline">
                Your name: <input type="text" ng-model="username" value="<?php echo $fName ?>">
            </form>
            <?php } ?>
            <div ng-cloak ng-repeat="message in messages">
                <em>{{message.from}}: </em>{{message.content}}
            </div><br/>
            <form class="form-inline" ng-submit="addMessage()">
                <input type="text" ng-model="message" placeholder="Message...">
                <button class="btn" type="submit">
                    <i class="icon-reply"> Send</i>
                </button>
            </form>
        </div>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.2.1/angular.min.js"></script>
        <script src="https://cdn.firebase.com/v0/firebase.js"></script>
        <script src="https://cdn.firebase.com/libs/angularfire/0.5.0/angularfire.min.js"></script>
        <script type="text/javascript">
            angular.module('chat', ['firebase']).controller('Chat', ['$scope', '$firebase',
                function($scope, $firebase) {
                    var ref = new Firebase('https://angularfire.firebaseio.com/chat');
                    $scope.messages = $firebase(ref.limit(15));
                    $scope.username = '<?php echo $fName ?>';
                    $scope.addMessage = function() {
                        $scope.messages.$add({
                            from: $scope.username, content: $scope.message
                        });
                        $scope.message = "";
                    }}]);
        </script>
    </div>
</div>




<?php include('footer.php') ?>