cri-2014 · michaeluskov · Sep 30, 2014 · Oct 1, 2014 · Oct 1, 2014 · Oct 1, 2014
diff --git a/trafficlights.html b/trafficlights.html
@@ -0,0 +1,13 @@
+<html>
+<head>
+<title>Traffic Lights</title>
+</head>
+<body>
+<button onclick="javascript:changeDOM()">Color?</button>
+<p id="colorParagraph"></p>
+<button onclick="javascript:tl.toRed()">To red</button>
+<button onclick="javascript:tl.toYellow()">To yellow</button>
+<button onclick="javascript:tl.toGreen()">To green</button>
+</body>
+<script type="text/javascript" src="trafficlights.js"></script>
+</html>
diff --git a/trafficlights.js b/trafficlights.js
@@ -0,0 +1,256 @@
+/**
+ * Constructs EventEmitter
+ *
+ * @constructor
+ * @this {EventEmitter}
+ */
+
+function EventEmitter() {
+    /** @private */ this.__listeners = {};
+
+/**
+ * Adds event listener
+ *
+ *
+ * @this {EventEmitter}
+ * @param {string} event 
+ * @param {func} listener
+ */	
+    EventEmitter.prototype.addListener = function (event, listener) {
+        if (this.__listeners[event] === undefined) {
+            this.__listeners[event] = [];
+        }
+        this.__listeners[event].push(listener);
+    };
+
+/**
+ * Removes event listener
+ *
+ *
+ * @this {EventEmitter}
+ * @param {string} event 
+ * @param {func} listener
+ */	
+    EventEmitter.prototype.removeListener = function (event, listener) {
+        if (this.__listeners[event] !== undefined) {
+            for (var i = 0; i < this.__listeners[event].length; i++) {
+                if (this.__listeners[event][i] === listener)
+                    this.__listeners[event].splice(i,1);
+            }
+        }
+    };
+
+/**
+ * Returns function to call in setTimeout
+ *
+ * @private
+ * @this {EventEmitter}
+ * @param {string} event 
+ * @param {int} position
+ * @param {string} data Optional data
+ */		
+	EventEmitter.prototype.__returnFunction = function (event, position, data) {
+		return function () {
+			this.__listeners[event][position](data);
+		}.bind(this);
+	};
+
+/**
+ * Emits event
+ *
+ *
+ * @this {EventEmitter}
+ * @param {string} event 
+ * @param {string} data Optional data
+ */		
+    EventEmitter.prototype.emit = function (event, data) {
+        if (this.__listeners[event] !== undefined) {
+            for (var i = 0; i < this.__listeners[event].length; i++) {
+                setTimeout(this.__returnFunction(event, i, data), 0);
+            }
+        }
+    };
+
+}
+
+/**
+ * Constructs new TrafficLight object
+ *
+ *
+ * @this {TrafficLight}
+ * @constructor
+ * @param {int} redTime
+ * @param {int} yellowTime
+ * @param {int} greenTime
+ */
+
+function TrafficLight(redTime, yellowTime, greenTime) { 
+    /** @private */ this.__trammode = null;
+    /** @private */ this.__tramtimer = null;
+    /** @private */ this.__timer = null;
+    /** @private */ this.__tramstate = null;
+    /** @private */ this.__state = null;
+    /** @private */ this.__stateChangedTime = null;
+    /** @private */ this.__redTime = redTime;
+    /** @private */ this.__yellowTime = yellowTime;
+    /** @private */ this.__greenTime = greenTime;
+    /** @private */ this.__tramWaitTime = 3000;
+    /** @private */ this.__tramGreenTime = 10000;
+    /** @private */ this.__usefulCoefficient = 0.7;
+
+
+/**
+ * Sets new timer for color changes and checks if the is only one timer
+ *
+ * @private
+ * @this {TrafficLight}
+ * @param {int} delay 
+ * @param {func} func
+ * @param {string} data Optional data
+ */	
+    TrafficLight.prototype.__setnewtimer = function (delay, func) {
+        if (this.__timer) {
+            clearTimeout(this.__timer);
+        }
+        this.__stateChangedTime = new Date();
+        this.__timer = setTimeout(func, delay);
+    };
+
+/**
+ * Returns amount of time this color should be active
+ *
+ * @private
+ * @this {TrafficLight}
+ */		
+    TrafficLight.prototype.__currentStateTime = function () {
+        return this['__' + this.__state + 'Time'];
+    };
+
+/**
+ * Changes color to red
+ *
+ * @this {TrafficLight}
+ */	
+    TrafficLight.prototype.toRed = function () {
+        console.log('Changed to red');
+        this.__state = 'red';
+        this.__setnewtimer(this.__redTime, function () {
+            this.toGreen();
+        }.bind(this));
+    };
+
+/**
+ * Changes color to green
+ *
+ * @this {TrafficLight}
+ */	
+    TrafficLight.prototype.toGreen = function () {
+        console.log('Changed to green');
+        this.__state = 'green';
+        this.__setnewtimer(this.__greenTime, function () {
+            this.toYellow();
+        }.bind(this));
+    };
+
+/**
+ * Changes color to yellow
+ *
+ * @this {TrafficLight}
+ */	
+    TrafficLight.prototype.toYellow = function () {
+        console.log('Changed to yellow');
+        this.__state = 'yellow';
+        this.__setnewtimer(this.__yellowTime, function () {
+            this.toRed();
+        }.bind(this));
+    };
+
+/**
+ * Exits tram mode
+ *
+ * @private
+ * @this {TrafficLight}
+ */	
+    TrafficLight.prototype.__exittrammode = function () {
+        console.log('Exit tram mode');
+        this.__tramstate = null;
+        this.__trammode = null;
+        if (new Date() - this.__stateChangedTime > this.__usefulCoefficient * this.__currentStateTime()) {
+            switch (this.__state) {
+                case 'red': this.toGreen(); break;
+                case 'yellow': this.toRed(); break;
+                case 'green': this.toYellow(); break;
+            }
+        }
+    };
+
+/**
+ * Enters tram mode
+ *
+ * @private
+ * @this {TrafficLight}
+ */
+    TrafficLight.prototype.__entertrammode = function () {
+        console.log('Entering tram mode');
+        this.__trammode = 'using';
+        this.__tramstate = 'green';
+        this.__tramtimer = setTimeout(function () {
+                        this.__exittrammode();
+                    }.bind(this), this.__tramGreenTime);
+    };
+
+/**
+ * Tram mode enter callback for Tram event
+ *
+ * @private
+ * @this {TrafficLight}
+ */   
+    TrafficLight.prototype.__tramcallback = function (data) {
+        if (!this.__trammode) {
+            console.log('Handling tram event');
+            this.__trammode = 'waiting';
+            this.__tramtimer = setTimeout(function () {
+                        this.__entertrammode();
+                    }.bind(this), this.__tramWaitTime);
+        }
+    };
+
+/**
+ * Subscribes to Tram event of specified TrafficLight
+ *
+ * 
+ * @this {TrafficLight}
+ * @param {object} event
+ */
+    TrafficLight.prototype.tramsubscribe = function (event) {
+        event.addListener('tram', function() {
+                            this.__tramcallback();
+                        }.bind(this));
+    };	
+
+
+/**
+ * Returns current state
+ *
+ * 
+ * @this {TrafficLight}
+ */
+    TrafficLight.prototype.state = function () {
+        if (this.__trammode == 'using')
+            return this.__tramstate;
+        return this.__state;
+    };
+
+    this.toGreen();
+}
+
+changeDOM = function () {
+    document.getElementById('colorParagraph').innerHTML = tl.state();
+};
+
+
+var tl = new TrafficLight(5000, 5000, 5000);
+var event = new EventEmitter();
+tl.tramsubscribe(event);
+console.log('Tram event will emit in 3 seconds');
+setTimeout(function(){event.emit('tram')}, 3000);