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var Task = function (options) {
    var _options = options || {};

    var _description = _options.description || "";
    var _assignedTo = _options.assignedTo || "";
    var _duration = _options.duration || 0.0;

    var _tasks = [];

    return {
        description: _description,
        assignedTo: _assignedTo,
        duration: _duration,
        tasks: _tasks
    };
};

var TreeNode = function (options) {
        var _options = options || {};

        var _value = _options.value || {};
        var _children = _options.children || [];
        var _parent = _options.parent || null;

        //  Public methods
        var isRoot = function () {
            return (_parent == null);
        };

        var level = function () {
            return isRoot() ? 0 : _parent.level() + 1;
        };

        var addChild = function (value) {
            var childNode = new TreeNode({ value: value, parent: this });
            _children.push(childNode);

            return childNode;
        };

        return {
            value: _value,
            children: _children,
            parent: _parent,

            //  public methods
            isRoot: isRoot,
            level: level,
            addChild: addChild
        };
    };

var treeFuncs = function () {
    var buildTaskTree = function (sourceTasks) {
        var tree = new TreeNode({
            value: "ROOT"
        });

        var taskStack = [];
        var treeNodeTargetStack = [];

        taskStack.push(sourceTasks);
        treeNodeTargetStack.push(tree);

        while (taskStack.length > 0) {
            var currentTask = taskStack.pop();
            var targetNode = treeNodeTargetStack.pop();

            var length = currentTask.length;
            for (var i = 0; i < length; i++) {
                var task = currentTask[i];
                var childNode = targetNode.addChild(task);

                if (task.tasks.length > 0) {
                    taskStack.push(task.tasks);
                    treeNodeTargetStack.push(childNode);
                }
            }
        }

        return tree;
    };

    var traverseAndApply = function (treeNode, func, functionArgs) {
        var treeNodeStack = [];
        var rootArray = [];
        rootArray.push(treeNode);

        treeNodeStack.push(rootArray);

        while (treeNodeStack.length > 0) {
            var currentNodeList = treeNodeStack.pop();
            var length = currentNodeList.length;

            for (var i = 0; i < length; i++) {
                var currentNode = currentNodeList[i];
                if (currentNode.parent != null) {
                    func(currentNode.value, currentNode, functionArgs);
                }

                if (currentNode.children.length > 0) {
                    treeNodeStack.push(currentNode.children);
                }
            }
        }
    };

    return {
        buildTaskTree: buildTaskTree,
        traverseAndApply: traverseAndApply
    };
};

var Controller = function () {
    var _tasks = [];
    var _filterResultTasks = [];
    
    var _treeFuncs = new treeFuncs();

    var initTasks = function () {
        //    4 "Level 1
        _tasks.push(new Task({
            description: "Discuss Product Concept",
            assignedTo: "Jackie Chan; Frodo; Sauroman",
            duration: 4
        }));
        _tasks.push(new Task({
            description: "Create Mockups",
            assignedTo: "Frodo; Gimili;",
            duration: 8
        }));
        _tasks.push(new Task({
            description: "Setup POC environment",
            assignedTo: "Frodo; Gandalf",
            duration: 12
        }));
        _tasks.push(new Task({
            description: "POC Development",
            assignedTo: "Gandalf; Ilsildor; Aragorn",
            duration: 46
        }));

        //    Level 2
        _tasks[1].tasks.push(new Task({
            description: "Paper walk through",
            assignedTo: "Gimili;",
            duration: 6
        }));

        _tasks[1].tasks.push(new Task({
            description: "Convert to HTML",
            assignedTo: "Gimili;",
            duration: 2
        }));

        _tasks[2].tasks.push(new Task({
            description: "Determine SQL or NoSQL database",
            assignedTo: "Gandalf; Frodo",
            duration: 2
        }));

        _tasks[2].tasks.push(new Task({
            description: "Setup Heroku",
            assignedTo: "Gandalf; Frodo",
            duration: 5
        }));

        _tasks[2].tasks.push(new Task({
            description: "Setup Nodejs",
            assignedTo: "Gandalf; Frodo",
            duration: 5
        }));

        _tasks[3].tasks.push(new Task({
            description: "Create Backlog",
            assignedTo: "Ilsildor;",
            duration: 10
        }));

        _tasks[3].tasks.push(new Task({
            description: "TDD Sprint",
            assignedTo: "Aragorn;",
            duration: 10
        }));

        _tasks[3].tasks.push(new Task({
            description: "QA Review",
            assignedTo: "Gandalf;",
            duration: 10
        }));

        //    Level 3 for 'Create Backlog'
        _tasks[3].tasks[0].tasks.push(new Task({
            description: "Confirm users stories",
            assignedTo: "Isildor; Jackie Chan",
            duration: 2
        }));

        _tasks[3].tasks[0].tasks.push(new Task({
            description: "Check Team schedule",
            assignedTo: "Isildor; ",
            duration: 3
        }));

        //    Level 3 for 'TDD Sprint'
        _tasks[3].tasks[1].tasks.push(new Task({
            description: "Confirm users stories",
            assignedTo: "Isildor; Jackie Chan",
            duration: 2
        }));

        _tasks[3].tasks[0].tasks.push(new Task({
            description: "Check Team schedule",
            assignedTo: "Isildor; ",
            duration: 3
        }));
    };
    
    var filterTopLevel = function(){
        var treeNode = _treeFuncs.buildTaskTree(_tasks);
        var matchTopLevelArgs = {};
        matchTopLevelArgs.results = []
        
        var matchTopLevelFunc = function(value, node, funcArgs){
            if(node.level() == 1){
                funcArgs.results.push(value);
            }
        };
        
        _treeFuncs.traverseAndApply(treeNode, matchTopLevelFunc, matchTopLevelArgs);
        
        var template = Handlebars.compile($("#filterDisplay").html());
        var resultHTML = template({
            tasks: matchTopLevelArgs.results
        });

        $("#filterResultDisplay").html(resultHTML);
    };
    
    var filterFrodoTasks = function(){
        var treeNode = _treeFuncs.buildTaskTree(_tasks);
        
        var frodoTasksArgs = {};
        frodoTasksArgs.results = [];
        
        var frodoTasksFunc = function(value, node, funcArgs){
            if((value.assignedTo.indexOf("Frodo") > -1) & (node.level() != 1)){
                funcArgs.results.push(value);
            }
        };
        
        _treeFuncs.traverseAndApply(treeNode, frodoTasksFunc, frodoTasksArgs);
        
        var template = Handlebars.compile($("#filterDisplay").html());
        var resultHTML = template({
            tasks: frodoTasksArgs.results
        });

        $("#filterResultDisplay").html(resultHTML);
    };

    return {
        tasks: _tasks,
        filterResultTasks: _filterResultTasks,
        initTasks: initTasks,
        
        //    Filters
        filterTopLevel: filterTopLevel,
        filterFrodoTasks: filterFrodoTasks
    };
};

$(document).ready(function () {
    var controller = new Controller();
    controller.initTasks();

    var projectSource = $("#projectDisplay").html();
    Handlebars.registerPartial("taskDisplay", $("#taskDisplay").html());

    var template = Handlebars.compile(projectSource);
    var resultHTML = template({
        tasks: controller.tasks
    });

    $("#projectPlan").html(resultHTML);
    
    window["controller"] = controller;
});

<div style="padding: 8px;">
    <div id="apparea" role="tabpanel">
        <ul class="nav nav-tabs" role="tablist">
            <li role="presentation" class="active"><a href="#projectlist" aria-controls="projectplan" role="tab" data-toggle="tab">Project Plan</a>

            </li>
            <li role="presentation"><a href="#filters" aria-controls="filters" role="tab" data-toggle="tab">Filtering Examples</a>

            </li>
        </ul>
        <div class="tab-content demo">
            <div role="tabpanel" class="tab-pane active" id="projectlist">
                 <h3>Project Plan</h3>
                <div id="projectPlan"></div>
            </div>
            <div role="tabpanel" class="tab-pane active" id="filters">
                <div id="filterResultDisplay" class="filter-results">
                </div>
                <p>
                    <button type="button" onclick="controller.filterTopLevel();">Filter Top Level</button>
                </p>
                <p>
                    <button type="button" onclick="controller.filterFrodoTasks();">Filter Frodo's Tasks</button>
                </p>
            </div>
        </div>
    </div>
</div>
<script id="projectDisplay" type="text/x-handlebars-template">
    <ul class = "project-list">
        {{> taskDisplay}}
    </ul>
</script>

<script id="taskDisplay" type="text/x-handlebars-template">
    {{#each tasks}} 
        <li class = "list-item"> 
            <span class = "task-name">{{description}}</span> | Team: {{assignedTo}} | Duration: {{duration}} (hrs)
        {{#if tasks}}
            <ul class="project-list">
            {{> taskDisplay}}
            </ul>
        {{/if}}
        </li > 
     {{/each}}
</script>

<script id="filterDisplay" type="text/x-handlebars-template">
    <ul class = "project-list">
        {{#each tasks}}
        <li>
            <span class = "task-name">{{description}}</span> | Team: {{assignedTo}} | Duration: {{duration}} (hrs)        
        </li>
        {{/each}}
    </ul>
</script>

div.demo {
    margin-top: 8px;
}

div.filter-results{
    border-color: #ddd;
    border-style: solid;
    border-width: 1px;
    margin-bottom: 6px;
    min-height: 200px;
    overflow: scroll;
}
li.list-item {
    margin-top: 4px;
}
span.task-name {
    font-weight: bold;
    font-style: italic;
}
ul.project-list {
    list-style-type: none;
    margin-bottom: 8px;
    margin-left: 12px;
    margin-top: 8px;
    text-decoration: none;
}