GUI -- Implemented the flash service.

Change-Id: I4fb03f4c8df687ab499921d1bf2b8cb424ec306e

+/*
+ * Copyright 2014,2015 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 GUI -- Flash Service -- CSS file
+ */
+
+#flash {
+    z-index: 1400;
+}
+
+#flash svg {
+    position: absolute;
+    bottom: 0;
+    opacity: 0.8;
+}
+
+.light #flash svg g.flashItem rect {
+    fill: #ccc;
+}
+.dark #flash svg g.flashItem rect {
+    fill: #555;
+}
+
+#flash svg g.flashItem text {
+    stroke: none;
+    text-anchor: middle;
+    alignment-baseline: middle;
+    font-size: 16pt;
+}
+.light #flash svg g.flashItem text {
+    fill: #333;
+}
+.dark #flash svg g.flashItem text {
+    fill: #999;
+}

+/*
+ * Copyright 2015 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 GUI -- Layer -- Flash Service
+
+ Provides a mechanism to flash short informational messages to the screen
+ to alert the user of something, e.g. "Hosts visible" or "Hosts hidden".
+ */
+(function () {
+    'use strict';
+
+    // injected references
+    var $log, $timeout;
+
+    // configuration
+    var defaultSettings = {
+            fade: 200,
+            showFor: 1200
+        },
+        w = '100%',
+        h = 200,
+        xpad = 20,
+        ypad = 10,
+        rx = 10,
+        vbox = '-200 -' + (h/2) + ' 400 ' + h;
+
+    // internal state
+    var settings,
+        timer = null,
+        data = [];
+
+    // DOM elements
+    var flashDiv, svg;
+
+
+    function computeBox(el) {
+        var text = el.select('text'),
+            box = text.node().getBBox();
+
+        // center
+        box.x = -box.width / 2;
+        box.y = -box.height / 2;
+
+        // add some padding
+        box.x -= xpad;
+        box.width += xpad * 2;
+        box.y -= ypad;
+        box.height += ypad * 2;
+
+        return box;
+    }
+
+    function updateFlash() {
+        if (!svg) {
+            svg = flashDiv.append('svg').attr({
+                width: w,
+                height: h,
+                viewBox: vbox
+            });
+        }
+
+        var items = svg.selectAll('.flashItem')
+            .data(data);
+
+        // this is when there is an existing item
+        items.each(function (msg) {
+            var el = d3.select(this),
+                box;
+
+            el.select('text').text(msg);
+            box = computeBox(el);
+            el.select('rect').attr(box);
+        });
+
+
+        // this is when there is no existing item
+        var entering = items.enter()
+            .append('g')
+            .attr({
+                class: 'flashItem',
+                opacity: 0
+            })
+            .transition()
+            .duration(settings.fade)
+            .attr('opacity', 1);
+
+        entering.each(function (msg) {
+            var el = d3.select(this),
+                box;
+
+            el.append('rect').attr('rx', rx);
+            el.append('text').text(msg);
+            box = computeBox(el);
+            el.select('rect').attr(box);
+        });
+
+        items.exit()
+            .transition()
+            .duration(settings.fade)
+            .attr('opacity', 0)
+            .remove();
+
+        if (svg && data.length === 0) {
+            svg.transition()
+                .delay(settings.fade + 10)
+                .remove();
+            svg = null;
+        }
+    }
+
+    function flash(msg) {
+        if (timer) {
+            $timeout.cancel(timer);
+        }
+
+        timer = $timeout(function () {
+            data = [];
+            updateFlash();
+        }, settings.showFor);
+
+        data = [msg];
+        updateFlash();
+    }
+
+    angular.module('onosLayer')
+        .factory('FlashService', ['$log', '$timeout',
+        function (_$log_, _$timeout_) {
+            $log = _$log_;
+            $timeout = _$timeout_;
+
+            function initFlash(opts) {
+                settings = angular.extend({}, defaultSettings, opts);
+                flashDiv = d3.select('#flash');
+            }
+
+            return {
+                initFlash: initFlash,
+                flash: flash
+            };
+        }]);
+
+}());

@@ -60,6 +60,7 @@
 
     <script src="fw/layer/layer.js"></script>
     <script src="fw/layer/panel.js"></script>
+    <script src="fw/layer/flash.js"></script>
 
     <!-- Framework and library stylesheets included here -->
     <!-- TODO: use a single catenated-minified file here -->
@@ -69,6 +70,7 @@
     <link rel="stylesheet" href="fw/svg/glyph.css">
     <link rel="stylesheet" href="fw/svg/icon.css">
     <link rel="stylesheet" href="fw/layer/panel.css">
+    <link rel="stylesheet" href="fw/layer/flash.css">
     <link rel="stylesheet" href="fw/nav/nav.css">
 
     <!-- This is where contributed javascript will get injected -->

@@ -65,8 +65,9 @@
         .controller('OnosCtrl', [
             '$log', '$route', '$routeParams', '$location',
             'KeyService', 'ThemeService', 'GlyphService', 'PanelService',
+            'FlashService',
 
-        function ($log, $route, $routeParams, $location, ks, ts, gs, ps) {
+        function ($log, $route, $routeParams, $location, ks, ts, gs, ps, flash) {
             var self = this;
 
             self.$route = $route;
@@ -79,6 +80,7 @@
             ks.installOn(d3.select('body'));
             gs.init();
             ps.init();
+            flash.initFlash();
 
             $log.log('OnosCtrl has been created');
 

+/*
+ * Copyright 2015 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 GUI -- Layer -- Flash Service - Unit Tests
+ */
+describe('factory: fw/layer/flash.js', function () {
+    var $log, $timeout, fs, flash, d3Elem;
+
+    beforeEach(module('onosLayer'));
+
+    beforeEach(inject(function (_$log_, _$timeout_, FnService, FlashService) {
+        $log = _$log_;
+        $timeout = _$timeout_;
+        fs = FnService;
+        flash = FlashService;
+        d3Elem = d3.select('body').append('div').attr('id', 'myflashdiv');
+        flash.initFlash();
+    }));
+
+    afterEach(function () {
+        d3.select('#myflashdiv').remove();
+    });
+
+    function flashItemSelection() {
+        return d3Elem.selectAll('.flashItem');
+    }
+
+    it('should define FlashService', function () {
+        expect(flash).toBeDefined();
+    });
+
+    it('should define api functions', function () {
+        expect(fs.areFunctions(flash, [
+            'initFlash', 'flash'
+        ])).toBeTruthy();
+    });
+
+    it('should have no items to start', function () {
+        expect(flashItemSelection().size()).toBe(0);
+    });
+
+    it('should flash the message Foo', function () {
+        var item, rect, text;
+        flash.flash('foo');
+        setTimeout(function () {
+            item = flashItemSelection();
+            expect(item.size()).toEqual(1);
+            expect(item.classed('flashItem')).toBeTruthy();
+            expect(item.select('rect').size()).toEqual(1);
+            text = item.select('text');
+            expect(text.size()).toEqual(1);
+            expect(text.text()).toEqual('foo');
+        }, 500);
+    });
+
+    // TODO: testing these time-sensitive behaviors is hard...
+    //  need to work on this some other time.
+});