Restructuring GUI code - first pass - WIP.
diff --git a/web/gui/src/main/webapp/topo2.js b/web/gui/src/main/webapp/topo2.js
new file mode 100644
index 0000000..b249c09
--- /dev/null
+++ b/web/gui/src/main/webapp/topo2.js
@@ -0,0 +1,1222 @@
+/*
+ * Copyright 2014 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ ONOS network topology viewer - PoC version 1.0
+
+ @author Simon Hunt
+ */
+
+(function (onos) {
+    'use strict';
+
+    // reference to the framework api
+    var api = onos.api;
+
+    // configuration data
+    var config = {
+        useLiveData: true,
+        debugOn: false,
+        debug: {
+            showNodeXY: false,
+            showKeyHandler: true
+        },
+        options: {
+            layering: true,
+            collisionPrevention: true,
+            loadBackground: true
+        },
+        backgroundUrl: 'img/us-map.png',
+        data: {
+            live: {
+                jsonUrl: 'rs/topology/graph',
+                detailPrefix: 'rs/topology/graph/',
+                detailSuffix: ''
+            },
+            fake: {
+                jsonUrl: 'json/network2.json',
+                detailPrefix: 'json/',
+                detailSuffix: '.json'
+            }
+        },
+        iconUrl: {
+            device: 'img/device.png',
+            host: 'img/host.png',
+            pkt: 'img/pkt.png',
+            opt: 'img/opt.png'
+        },
+        mastHeight: 36,
+        force: {
+            note: 'node.class or link.class is used to differentiate',
+            linkDistance: {
+                infra: 200,
+                host: 40
+            },
+            linkStrength: {
+                infra: 1.0,
+                host: 1.0
+            },
+            charge: {
+                device: -800,
+                host: -1000
+            },
+            ticksWithoutCollisions: 50,
+            marginLR: 20,
+            marginTB: 20,
+            translate: function() {
+                return 'translate(' +
+                    config.force.marginLR + ',' +
+                    config.force.marginTB + ')';
+            }
+        },
+        labels: {
+            imgPad: 16,
+            padLR: 8,
+            padTB: 6,
+            marginLR: 3,
+            marginTB: 2,
+            port: {
+                gap: 3,
+                width: 18,
+                height: 14
+            }
+        },
+        icons: {
+            w: 32,
+            h: 32,
+            xoff: -12,
+            yoff: -8
+        },
+        constraints: {
+            ypos: {
+                host: 0.05,
+                switch: 0.3,
+                roadm: 0.7
+            }
+        },
+        hostLinkWidth: 1.0,
+        hostRadius: 7,
+        mouseOutTimerDelayMs: 120
+    };
+
+    // state variables
+    var view = {},
+        network = {},
+        selected = {},
+        highlighted = null,
+        hovered = null,
+        viewMode = 'showAll',
+        portLabelsOn = false;
+
+
+    function debug(what) {
+        return config.debugOn && config.debug[what];
+    }
+
+    function urlData() {
+        return config.data[config.useLiveData ? 'live' : 'fake'];
+    }
+
+    function networkJsonUrl() {
+        return urlData().jsonUrl;
+    }
+
+    function safeId(id) {
+        return id.replace(/[^a-z0-9]/gi, '_');
+    }
+
+    function detailJsonUrl(id) {
+        var u = urlData(),
+            encId = config.useLiveData ? encodeURIComponent(id) : safeId(id);
+        return u.detailPrefix + encId + u.detailSuffix;
+    }
+
+
+    // load the topology view of the network
+    function loadNetworkView() {
+        // Hey, here I am, calling something on the ONOS api:
+        api.printTime();
+
+        resize();
+
+        // go get our network data from the server...
+        var url = networkJsonUrl();
+        d3.json(url , function (err, data) {
+            if (err) {
+                alert('Oops! Error reading JSON...\n\n' +
+                    'URL: ' + url + '\n\n' +
+                    'Error: ' + err.message);
+                return;
+            }
+//            console.log("here is the JSON data...");
+//            console.log(data);
+
+            network.data = data;
+            drawNetwork();
+        });
+
+        // while we wait for the data, set up the handlers...
+        setUpClickHandler();
+        setUpRadioButtonHandler();
+        setUpKeyHandler();
+        $(window).on('resize', resize);
+    }
+
+    function setUpClickHandler() {
+        // click handler for "selectable" objects
+        $(document).on('click', '.select-object', function () {
+            // when any object of class "select-object" is clicked...
+            var obj = network.lookup[$(this).data('id')];
+            if (obj) {
+                selectObject(obj);
+            }
+            // stop propagation of event (I think) ...
+            return false;
+        });
+    }
+
+    function setUpRadioButtonHandler() {
+        d3.selectAll('#displayModes .radio').on('click', function () {
+            var id = d3.select(this).attr('id');
+            if (id !== viewMode) {
+                radioButton('displayModes', id);
+                viewMode = id;
+                doRadioAction(id);
+            }
+        });
+    }
+
+    function doRadioAction(id) {
+        showAllLayers();
+        if (id === 'showPkt') {
+            showPacketLayer();
+        } else if (id === 'showOpt') {
+            showOpticalLayer();
+        }
+    }
+
+    function showAllLayers() {
+        network.node.classed('inactive', false);
+        network.link.classed('inactive', false);
+        d3.selectAll('svg .port').classed('inactive', false)
+        d3.selectAll('svg .portText').classed('inactive', false)
+    }
+
+    function showPacketLayer() {
+        network.node.each(function(d) {
+            // deactivate nodes that are not hosts or switches
+            if (d.class === 'device' && d.type !== 'switch') {
+                d3.select(this).classed('inactive', true);
+            }
+        });
+
+        network.link.each(function(lnk) {
+            // deactivate infrastructure links that have opt's as endpoints
+            if (lnk.source.type === 'roadm' || lnk.target.type === 'roadm') {
+                d3.select(this).classed('inactive', true);
+            }
+        });
+
+        // deactivate non-packet ports
+        d3.selectAll('svg .optPort').classed('inactive', true)
+    }
+
+    function showOpticalLayer() {
+        network.node.each(function(d) {
+            // deactivate nodes that are not optical devices
+            if (d.type !== 'roadm') {
+                d3.select(this).classed('inactive', true);
+            }
+        });
+
+        network.link.each(function(lnk) {
+            // deactivate infrastructure links that have opt's as endpoints
+            if (lnk.source.type !== 'roadm' || lnk.target.type !== 'roadm') {
+                d3.select(this).classed('inactive', true);
+            }
+        });
+
+        // deactivate non-packet ports
+        d3.selectAll('svg .pktPort').classed('inactive', true)
+    }
+
+    function setUpKeyHandler() {
+        d3.select('body')
+            .on('keydown', function () {
+                processKeyEvent();
+                if (debug('showKeyHandler')) {
+                    network.svg.append('text')
+                        .attr('x', 5)
+                        .attr('y', 15)
+                        .style('font-size', '20pt')
+                        .text('keyCode: ' + d3.event.keyCode +
+                            ' applied to : ' + contextLabel())
+                        .transition().duration(2000)
+                        .style('font-size', '2pt')
+                        .style('fill-opacity', 0.01)
+                        .remove();
+                }
+            });
+    }
+
+    function contextLabel() {
+        return hovered === null ? "(nothing)" : hovered.id;
+    }
+
+    function radioButton(group, id) {
+        d3.selectAll("#" + group + " .radio").classed("active", false);
+        d3.select("#" + group + " #" + id).classed("active", true);
+    }
+
+    function processKeyEvent() {
+        var code = d3.event.keyCode;
+        switch (code) {
+            case 66:    // B
+                toggleBackground();
+                break;
+            case 71:    // G
+                cycleLayout();
+                break;
+            case 76:    // L
+                cycleLabels();
+                break;
+            case 80:    // P
+                togglePorts();
+                break;
+            case 85:    // U
+                unpin();
+                break;
+        }
+
+    }
+
+    function toggleBackground() {
+        var bg = d3.select('#bg'),
+            vis = bg.style('visibility'),
+            newvis = (vis === 'hidden') ? 'visible' : 'hidden';
+        bg.style('visibility', newvis);
+    }
+
+    function cycleLayout() {
+        config.options.layering = !config.options.layering;
+        network.force.resume();
+    }
+
+    function cycleLabels() {
+        console.log('Cycle Labels - context = ' + contextLabel());
+    }
+
+    function togglePorts() {
+        portLabelsOn = !portLabelsOn;
+        var portVis = portLabelsOn ? 'visible' : 'hidden';
+        d3.selectAll('.port').style('visibility', portVis);
+        d3.selectAll('.portText').style('visibility', portVis);
+    }
+
+    function unpin() {
+        if (hovered) {
+            hovered.fixed = false;
+            findNodeFromData(hovered).classed('fixed', false);
+            network.force.resume();
+        }
+        console.log('Unpin - context = ' + contextLabel());
+    }
+
+
+    // ========================================================
+
+    function drawNetwork() {
+        $('#view').empty();
+
+        prepareNodesAndLinks();
+        createLayout();
+        console.log("\n\nHere is the augmented network object...");
+        console.log(network);
+    }
+
+    function prepareNodesAndLinks() {
+        network.lookup = {};
+        network.nodes = [];
+        network.links = [];
+
+        var nw = network.forceWidth,
+            nh = network.forceHeight;
+
+        function yPosConstraintForNode(n) {
+            return config.constraints.ypos[n.type || 'host'];
+        }
+
+        // Note that both 'devices' and 'hosts' get mapped into the nodes array
+
+        // first, the devices...
+        network.data.devices.forEach(function(n) {
+            var ypc = yPosConstraintForNode(n),
+                ix = Math.random() * 0.6 * nw + 0.2 * nw,
+                iy = ypc * nh,
+                node = {
+                    id: n.id,
+                    labels: n.labels,
+                    class: 'device',
+                    icon: 'device',
+                    type: n.type,
+                    x: ix,
+                    y: iy,
+                    constraint: {
+                        weight: 0.7,
+                        y: iy
+                    }
+                };
+            network.lookup[n.id] = node;
+            network.nodes.push(node);
+        });
+
+        // then, the hosts...
+        network.data.hosts.forEach(function(n) {
+            var ypc = yPosConstraintForNode(n),
+                ix = Math.random() * 0.6 * nw + 0.2 * nw,
+                iy = ypc * nh,
+                node = {
+                    id: n.id,
+                    labels: n.labels,
+                    class: 'host',
+                    icon: 'host',
+                    type: n.type,
+                    x: ix,
+                    y: iy,
+                    constraint: {
+                        weight: 0.7,
+                        y: iy
+                    }
+                };
+            network.lookup[n.id] = node;
+            network.nodes.push(node);
+        });
+
+
+        // now, process the explicit links...
+        network.data.links.forEach(function(lnk) {
+            var src = network.lookup[lnk.src],
+                dst = network.lookup[lnk.dst],
+                id = src.id + "-" + dst.id;
+
+            var link = {
+                class: 'infra',
+                id: id,
+                type: lnk.type,
+                width: lnk.linkWidth,
+                source: src,
+                srcPort: lnk.srcPort,
+                target: dst,
+                tgtPort: lnk.dstPort,
+                strength: config.force.linkStrength.infra
+            };
+            network.links.push(link);
+        });
+
+        // finally, infer host links...
+        network.data.hosts.forEach(function(n) {
+            var src = network.lookup[n.id],
+                dst = network.lookup[n.cp.device],
+                id = src.id + "-" + dst.id;
+
+            var link = {
+                class: 'host',
+                id: id,
+                type: 'hostLink',
+                width: config.hostLinkWidth,
+                source: src,
+                target: dst,
+                strength: config.force.linkStrength.host
+            };
+            network.links.push(link);
+        });
+    }
+
+    function createLayout() {
+
+        var cfg = config.force;
+
+        network.force = d3.layout.force()
+            .size([network.forceWidth, network.forceHeight])
+            .nodes(network.nodes)
+            .links(network.links)
+            .linkStrength(function(d) { return cfg.linkStrength[d.class]; })
+            .linkDistance(function(d) { return cfg.linkDistance[d.class]; })
+            .charge(function(d) { return cfg.charge[d.class]; })
+            .on('tick', tick);
+
+        network.svg = d3.select('#view').append('svg')
+            .attr('width', view.width)
+            .attr('height', view.height)
+            .append('g')
+            .attr('transform', config.force.translate());
+//            .attr('id', 'zoomable')
+//            .call(d3.behavior.zoom().on("zoom", zoomRedraw));
+
+        network.svg.append('svg:image')
+            .attr({
+                id: 'bg',
+                width: view.width,
+                height: view.height,
+                'xlink:href': config.backgroundUrl
+            })
+            .style('visibility',
+                    config.options.loadBackground ? 'visible' : 'hidden');
+
+//        function zoomRedraw() {
+//            d3.select("#zoomable").attr("transform",
+//                    "translate(" + d3.event.translate + ")"
+//                    + " scale(" + d3.event.scale + ")");
+//        }
+
+        // TODO: move glow/blur stuff to util script
+        var glow = network.svg.append('filter')
+            .attr('x', '-50%')
+            .attr('y', '-50%')
+            .attr('width', '200%')
+            .attr('height', '200%')
+            .attr('id', 'blue-glow');
+
+        glow.append('feColorMatrix')
+            .attr('type', 'matrix')
+            .attr('values', '0 0 0 0  0 ' +
+                '0 0 0 0  0 ' +
+                '0 0 0 0  .7 ' +
+                '0 0 0 1  0 ');
+
+        glow.append('feGaussianBlur')
+            .attr('stdDeviation', 3)
+            .attr('result', 'coloredBlur');
+
+        glow.append('feMerge').selectAll('feMergeNode')
+            .data(['coloredBlur', 'SourceGraphic'])
+            .enter().append('feMergeNode')
+            .attr('in', String);
+
+        // TODO: legend (and auto adjust on scroll)
+//        $('#view').on('scroll', function() {
+//
+//        });
+
+
+        // TODO: move drag behavior into separate method.
+        // == define node drag behavior...
+        network.draggedThreshold = d3.scale.linear()
+            .domain([0, 0.1])
+            .range([5, 20])
+            .clamp(true);
+
+        function dragged(d) {
+            var threshold = network.draggedThreshold(network.force.alpha()),
+                dx = d.oldX - d.px,
+                dy = d.oldY - d.py;
+            if (Math.abs(dx) >= threshold || Math.abs(dy) >= threshold) {
+                d.dragged = true;
+            }
+            return d.dragged;
+        }
+
+        network.drag = d3.behavior.drag()
+            .origin(function(d) { return d; })
+            .on('dragstart', function(d) {
+                d.oldX = d.x;
+                d.oldY = d.y;
+                d.dragged = false;
+                d.fixed |= 2;
+            })
+            .on('drag', function(d) {
+                d.px = d3.event.x;
+                d.py = d3.event.y;
+                if (dragged(d)) {
+                    if (!network.force.alpha()) {
+                        network.force.alpha(.025);
+                    }
+                }
+            })
+            .on('dragend', function(d) {
+                if (!dragged(d)) {
+                    selectObject(d, this);
+                }
+                d.fixed &= ~6;
+
+                // once we've finished moving, pin the node in position,
+                // if it is a device (not a host)
+                if (d.class === 'device') {
+                    d.fixed = true;
+                    d3.select(this).classed('fixed', true)
+                }
+            });
+
+        $('#view').on('click', function(e) {
+            if (!$(e.target).closest('.node').length) {
+                deselectObject();
+            }
+        });
+
+        // ...............................................................
+
+        // add links to the display
+        network.link = network.svg.append('g').attr('id', 'links')
+            .selectAll('.link')
+            .data(network.force.links(), function(d) {return d.id})
+            .enter().append('line')
+            .attr('class', function(d) {return 'link ' + d.class});
+
+        network.linkSrcPort = network.svg.append('g')
+            .attr({
+                id: 'srcPorts',
+                class: 'portLayer'
+            });
+        network.linkTgtPort = network.svg.append('g')
+            .attr({
+                id: 'tgtPorts',
+                class: 'portLayer'
+            });
+
+        var portVis = portLabelsOn ? 'visible' : 'hidden',
+            pw = config.labels.port.width,
+            ph = config.labels.port.height;
+
+        network.link.filter('.infra').each(function(d) {
+            var srcType = d.source.type === 'roadm' ? 'optPort' : 'pktPort',
+                tgtType = d.target.type === 'roadm' ? 'optPort' : 'pktPort';
+
+            if (d.source.type)
+
+            network.linkSrcPort.append('rect').attr({
+                id: 'srcPort-' + safeId(d.id),
+                class: 'port ' + srcType,
+                width: pw,
+                height: ph,
+                rx: 4,
+                ry: 4
+            }).style('visibility', portVis);
+
+            network.linkTgtPort.append('rect').attr({
+                id: 'tgtPort-' + safeId(d.id),
+                class: 'port ' + tgtType,
+                width: pw,
+                height: ph,
+                rx: 4,
+                ry: 4
+            }).style('visibility', portVis);
+
+            network.linkSrcPort.append('text').attr({
+                id: 'srcText-' + safeId(d.id),
+                class: 'portText ' + srcType
+            }).text(d.srcPort)
+                .style('visibility', portVis);
+
+            network.linkTgtPort.append('text').attr({
+                id: 'tgtText-' + safeId(d.id),
+                class: 'portText ' + tgtType
+            }).text(d.tgtPort)
+                .style('visibility', portVis);
+        });
+
+        // ...............................................................
+
+        // add nodes to the display
+        network.node = network.svg.selectAll('.node')
+            .data(network.force.nodes(), function(d) {return d.id})
+            .enter().append('g')
+            .attr('class', function(d) {
+                var cls = 'node ' + d.class;
+                if (d.type) {
+                    cls += ' ' + d.type;
+                }
+                return cls;
+            })
+            .attr('transform', function(d) {
+                return translate(d.x, d.y);
+            })
+            .call(network.drag)
+            .on('mouseover', function(d) {
+                // TODO: show tooltip
+                if (network.mouseoutTimeout) {
+                    clearTimeout(network.mouseoutTimeout);
+                    network.mouseoutTimeout = null;
+                }
+                hoverObject(d);
+            })
+            .on('mouseout', function(d) {
+                // TODO: hide tooltip
+                if (network.mouseoutTimeout) {
+                    clearTimeout(network.mouseoutTimeout);
+                    network.mouseoutTimeout = null;
+                }
+                network.mouseoutTimeout = setTimeout(function() {
+                    hoverObject(null);
+                }, config.mouseOutTimerDelayMs);
+            });
+
+
+        // deal with device nodes first
+        network.nodeRect = network.node.filter('.device')
+            .append('rect')
+            .attr({
+                rx: 5,
+                ry: 5,
+                width: 100,
+                height: 12
+            });
+            // note that width/height are adjusted to fit the label text
+            // then padded, and space made for the icon.
+
+        network.node.filter('.device').each(function(d) {
+            var node = d3.select(this),
+                icon = iconUrl(d);
+
+            node.append('text')
+            // TODO: add label cycle behavior
+                .text(d.id)
+                .attr('dy', '1.1em');
+
+            if (icon) {
+                var cfg = config.icons;
+                node.append('svg:image')
+                    .attr({
+                        width: cfg.w,
+                        height: cfg.h,
+                        'xlink:href': icon
+                    });
+                // note, icon relative positioning (x,y) is done after we have
+                // adjusted the bounds of the rectangle...
+            }
+
+            // debug function to show the modelled x,y coordinates of nodes...
+            if (debug('showNodeXY')) {
+                node.select('rect').attr('fill-opacity', 0.5);
+                node.append('circle')
+                    .attr({
+                        class: 'debug',
+                        cx: 0,
+                        cy: 0,
+                        r: '3px'
+                    });
+            }
+        });
+
+        // now process host nodes
+        network.nodeCircle = network.node.filter('.host')
+            .append('circle')
+            .attr({
+                r: config.hostRadius
+            });
+
+        network.node.filter('.host').each(function(d) {
+            var node = d3.select(this),
+                icon = iconUrl(d);
+
+            // debug function to show the modelled x,y coordinates of nodes...
+            if (debug('showNodeXY')) {
+                node.select('circle').attr('fill-opacity', 0.5);
+                node.append('circle')
+                    .attr({
+                        class: 'debug',
+                        cx: 0,
+                        cy: 0,
+                        r: '3px'
+                    });
+            }
+        });
+
+        // this function is scheduled to happen soon after the given thread ends
+        setTimeout(function() {
+            var lab = config.labels,
+                portGap = lab.port.gap,
+                midW = portGap + lab.port.width/ 2,
+                midH = portGap + lab.port.height / 2;
+
+            // post process the device nodes, to pad their size to fit the
+            // label text and attach the icon to the right location.
+            network.node.filter('.device').each(function(d) {
+                // for every node, recompute size, padding, etc. so text fits
+                var node = d3.select(this),
+                    text = node.select('text'),
+                    box = adjustRectToFitText(node);
+
+                // now make the computed adjustment
+                node.select('rect')
+                    .attr(box);
+
+                node.select('image')
+                    .attr('x', box.x + config.icons.xoff)
+                    .attr('y', box.y + config.icons.yoff);
+
+                var bounds = boundsFromBox(box),
+                    portBounds = {
+                        x1: bounds.x1 - midW,
+                        x2: bounds.x2 + midW,
+                        y1: bounds.y1 - midH,
+                        y2: bounds.y2 + midH
+                    };
+
+                // todo: clean up extent and edge work..
+                d.extent = {
+                    left: bounds.x1 - lab.marginLR,
+                    right: bounds.x2 + lab.marginLR,
+                    top: bounds.y1 - lab.marginTB,
+                    bottom: bounds.y2 + lab.marginTB
+                };
+
+                d.edge = {
+                    left   : new geo.LineSegment(bounds.x1, bounds.y1, bounds.x1, bounds.y2),
+                    right  : new geo.LineSegment(bounds.x2, bounds.y1, bounds.x2, bounds.y2),
+                    top    : new geo.LineSegment(bounds.x1, bounds.y1, bounds.x2, bounds.y1),
+                    bottom : new geo.LineSegment(bounds.x1, bounds.y2, bounds.x2, bounds.y2)
+                };
+
+                d.portEdge = {
+                    left   : new geo.LineSegment(
+                        portBounds.x1, portBounds.y1, portBounds.x1, portBounds.y2
+                    ),
+                    right  : new geo.LineSegment(
+                        portBounds.x2, portBounds.y1, portBounds.x2, portBounds.y2
+                    ),
+                    top    : new geo.LineSegment(
+                        portBounds.x1, portBounds.y1, portBounds.x2, portBounds.y1
+                    ),
+                    bottom : new geo.LineSegment(
+                        portBounds.x1, portBounds.y2, portBounds.x2, portBounds.y2
+                    )
+                };
+
+            });
+
+            network.numTicks = 0;
+            network.preventCollisions = false;
+            network.force.start();
+            for (var i = 0; i < config.force.ticksWithoutCollisions; i++) {
+                network.force.tick();
+            }
+            network.preventCollisions = true;
+            $('#view').css('visibility', 'visible');
+        });
+
+
+        // returns the newly computed bounding box of the rectangle
+        function adjustRectToFitText(n) {
+            var text = n.select('text'),
+                box = text.node().getBBox(),
+                lab = config.labels;
+
+            // not sure why n.data() returns an array of 1 element...
+            var data = n.data()[0];
+
+            text.attr('text-anchor', 'middle')
+                .attr('y', '-0.8em')
+                .attr('x', lab.imgPad/2)
+            ;
+
+            // translate the bbox so that it is centered on [x,y]
+            box.x = -box.width / 2;
+            box.y = -box.height / 2;
+
+            // add padding
+            box.x -= (lab.padLR + lab.imgPad/2);
+            box.width += lab.padLR * 2 + lab.imgPad;
+            box.y -= lab.padTB;
+            box.height += lab.padTB * 2;
+
+            return box;
+        }
+
+        function boundsFromBox(box) {
+            return {
+                x1: box.x,
+                y1: box.y,
+                x2: box.x + box.width,
+                y2: box.y + box.height
+            };
+        }
+
+    }
+
+    function iconUrl(d) {
+        return 'img/' + d.type + '.png';
+//        return config.iconUrl[d.icon];
+    }
+
+    function translate(x, y) {
+        return 'translate(' + x + ',' + y + ')';
+    }
+
+    // prevents collisions amongst device nodes
+    function preventCollisions() {
+        var quadtree = d3.geom.quadtree(network.nodes),
+            hrad = config.hostRadius;
+
+        network.nodes.forEach(function(n) {
+            var nx1, nx2, ny1, ny2;
+
+            if (n.class === 'device') {
+                nx1 = n.x + n.extent.left;
+                nx2 = n.x + n.extent.right;
+                ny1 = n.y + n.extent.top;
+                ny2 = n.y + n.extent.bottom;
+
+            } else {
+                nx1 = n.x - hrad;
+                nx2 = n.x + hrad;
+                ny1 = n.y - hrad;
+                ny2 = n.y + hrad;
+            }
+
+            quadtree.visit(function(quad, x1, y1, x2, y2) {
+                if (quad.point && quad.point !== n) {
+                    // check if the rectangles/circles intersect
+                    var p = quad.point,
+                        px1, px2, py1, py2, ix;
+
+                    if (p.class === 'device') {
+                        px1 = p.x + p.extent.left;
+                        px2 = p.x + p.extent.right;
+                        py1 = p.y + p.extent.top;
+                        py2 = p.y + p.extent.bottom;
+
+                    } else {
+                        px1 = p.x - hrad;
+                        px2 = p.x + hrad;
+                        py1 = p.y - hrad;
+                        py2 = p.y + hrad;
+                    }
+
+                    ix = (px1 <= nx2 && nx1 <= px2 && py1 <= ny2 && ny1 <= py2);
+
+                    if (ix) {
+                        var xa1 = nx2 - px1, // shift n left , p right
+                            xa2 = px2 - nx1, // shift n right, p left
+                            ya1 = ny2 - py1, // shift n up   , p down
+                            ya2 = py2 - ny1, // shift n down , p up
+                            adj = Math.min(xa1, xa2, ya1, ya2);
+
+                        if (adj == xa1) {
+                            n.x -= adj / 2;
+                            p.x += adj / 2;
+                        } else if (adj == xa2) {
+                            n.x += adj / 2;
+                            p.x -= adj / 2;
+                        } else if (adj == ya1) {
+                            n.y -= adj / 2;
+                            p.y += adj / 2;
+                        } else if (adj == ya2) {
+                            n.y += adj / 2;
+                            p.y -= adj / 2;
+                        }
+                    }
+                    return ix;
+                }
+            });
+
+        });
+    }
+
+    function tick(e) {
+        network.numTicks++;
+
+        if (config.options.layering) {
+            // adjust the y-coord of each node, based on y-pos constraints
+            network.nodes.forEach(function (n) {
+                var z = e.alpha * n.constraint.weight;
+                if (!isNaN(n.constraint.y)) {
+                    n.y = (n.constraint.y * z + n.y * (1 - z));
+                }
+            });
+        }
+
+        if (config.options.collisionPrevention && network.preventCollisions) {
+            preventCollisions();
+        }
+
+        var portHalfW = config.labels.port.width / 2,
+            portHalfH = config.labels.port.height / 2;
+
+        // clip visualization of links at bounds of nodes...
+        network.link.each(function(d) {
+            var xs = d.source.x,
+                ys = d.source.y,
+                xt = d.target.x,
+                yt = d.target.y,
+                line = new geo.LineSegment(xs, ys, xt, yt),
+                e, ix,
+                exs, eys, ext, eyt,
+                pxs, pys, pxt, pyt;
+
+            if (d.class === 'host') {
+                // no adjustment for source end of link, since hosts are dots
+                exs = xs;
+                eys = ys;
+
+            } else {
+                for (e in d.source.edge) {
+                    ix = line.intersect(d.source.edge[e].offset(xs, ys));
+                    if (ix.in1 && ix.in2) {
+                        exs = ix.x;
+                        eys = ix.y;
+
+                        // also pick off the port label intersection
+                        ix = line.intersect(d.source.portEdge[e].offset(xs, ys));
+                        pxs = ix.x;
+                        pys = ix.y;
+                        break;
+                    }
+                }
+            }
+
+            for (e in d.target.edge) {
+                ix = line.intersect(d.target.edge[e].offset(xt, yt));
+                if (ix.in1 && ix.in2) {
+                    ext = ix.x;
+                    eyt = ix.y;
+
+                    // also pick off the port label intersection
+                    ix = line.intersect(d.target.portEdge[e].offset(xt, yt));
+                    pxt = ix.x;
+                    pyt = ix.y;
+                    break;
+                }
+            }
+
+            // adjust the endpoints of the link's line to match rectangles
+            var sid = safeId(d.id);
+            d3.select(this)
+                .attr('x1', exs)
+                .attr('y1', eys)
+                .attr('x2', ext)
+                .attr('y2', eyt);
+
+            d3.select('#srcPort-' + sid)
+                .attr('x', pxs - portHalfW)
+                .attr('y', pys - portHalfH);
+
+            d3.select('#tgtPort-' + sid)
+                .attr('x', pxt - portHalfW)
+                .attr('y', pyt - portHalfH);
+
+            // TODO: fit label rect to size of port number.
+            d3.select('#srcText-' + sid)
+                .attr('x', pxs - 5)
+                .attr('y', pys + 3);
+
+            d3.select('#tgtText-' + sid)
+                .attr('x', pxt - 5)
+                .attr('y', pyt + 3);
+
+        });
+
+        // position each node by translating the node (group) by x,y
+        network.node
+            .attr('transform', function(d) {
+                return translate(d.x, d.y);
+            });
+
+    }
+
+    //    $('#docs-close').on('click', function() {
+    //        deselectObject();
+    //        return false;
+    //    });
+
+    //    $(document).on('click', '.select-object', function() {
+    //        var obj = graph.data[$(this).data('name')];
+    //        if (obj) {
+    //            selectObject(obj);
+    //        }
+    //        return false;
+    //    });
+
+    function findNodeFromData(d) {
+        var el = null;
+        network.node.filter('.' + d.class).each(function(n) {
+            if (n.id === d.id) {
+                el = d3.select(this);
+            }
+        });
+        return el;
+    }
+
+    function selectObject(obj, el) {
+        var node;
+        if (el) {
+            node = d3.select(el);
+        } else {
+            network.node.each(function(d) {
+                if (d == obj) {
+                    node = d3.select(el = this);
+                }
+            });
+        }
+        if (!node) return;
+
+        if (node.classed('selected')) {
+            deselectObject();
+            flyinPane(null);
+            return;
+        }
+        deselectObject(false);
+
+        selected = {
+            obj : obj,
+            el  : el
+        };
+
+        node.classed('selected', true);
+        flyinPane(obj);
+    }
+
+    function deselectObject(doResize) {
+        // Review: logic of 'resize(...)' function.
+        if (doResize || typeof doResize == 'undefined') {
+            resize(false);
+        }
+
+        // deselect all nodes in the network...
+        network.node.classed('selected', false);
+        selected = {};
+        flyinPane(null);
+    }
+
+    function flyinPane(obj) {
+        var pane = d3.select('#flyout'),
+            url;
+
+        if (obj) {
+            // go get details of the selected object from the server...
+            url = detailJsonUrl(obj.id);
+            d3.json(url, function (err, data) {
+                if (err) {
+                    alert('Oops! Error reading JSON...\n\n' +
+                        'URL: ' + url + '\n\n' +
+                        'Error: ' + err.message);
+                    return;
+                }
+//                console.log("JSON data... " + url);
+//                console.log(data);
+
+                displayDetails(data, pane);
+            });
+
+        } else {
+            // hide pane
+            pane.transition().duration(750)
+                .style('right', '-320px')
+                .style('opacity', 0.0);
+        }
+    }
+
+    function displayDetails(data, pane) {
+        $('#flyout').empty();
+
+        var title = pane.append("h2"),
+            table = pane.append("table"),
+            tbody = table.append("tbody");
+
+        $('<img src="img/' + data.type + '.png">').appendTo(title);
+        $('<span>').attr('class', 'icon').text(data.id).appendTo(title);
+
+
+        // TODO: consider using d3 data bind to TR/TD
+
+        data.propOrder.forEach(function(p) {
+            if (p === '-') {
+                addSep(tbody);
+            } else {
+                addProp(tbody, p, data.props[p]);
+            }
+        });
+
+        function addSep(tbody) {
+            var tr = tbody.append('tr');
+            $('<hr>').appendTo(tr.append('td').attr('colspan', 2));
+        }
+
+        function addProp(tbody, label, value) {
+            var tr = tbody.append('tr');
+
+            tr.append('td')
+                .attr('class', 'label')
+                .text(label + ' :');
+
+            tr.append('td')
+                .attr('class', 'value')
+                .text(value);
+        }
+
+        // show pane
+        pane.transition().duration(750)
+            .style('right', '20px')
+            .style('opacity', 1.0);
+    }
+
+    function highlightObject(obj) {
+        if (obj) {
+            if (obj != highlighted) {
+                // TODO set or clear "inactive" class on nodes, based on criteria
+                network.node.classed('inactive', function(d) {
+                    //                return (obj !== d &&
+                    //                    d.relation(obj.id));
+                    return (obj !== d);
+                });
+                // TODO: same with links
+                network.link.classed('inactive', function(d) {
+                    return (obj !== d.source && obj !== d.target);
+                });
+            }
+            highlighted = obj;
+        } else {
+            if (highlighted) {
+                // clear the inactive flag (no longer suppressed visually)
+                network.node.classed('inactive', false);
+                network.link.classed('inactive', false);
+            }
+            highlighted = null;
+
+        }
+    }
+
+    function hoverObject(obj) {
+        if (obj) {
+            hovered = obj;
+        } else {
+            if (hovered) {
+                hovered = null;
+            }
+        }
+    }
+
+
+    function resize() {
+        view.height = window.innerHeight - config.mastHeight;
+        view.width = window.innerWidth;
+        $('#view')
+            .css('height', view.height + 'px')
+            .css('width', view.width + 'px');
+
+        network.forceWidth = view.width - config.force.marginLR;
+        network.forceHeight = view.height - config.force.marginTB;
+    }
+
+    // ======================================================================
+    // register with the UI framework
+
+    api.addView('network', {
+        load: loadNetworkView
+    });
+
+
+}(ONOS));
+