Added session & session manager

models/session.js

@@ -0,0 +1,44 @@
+class Session {
+  constructor(id) {
+    this._id = id;
+    this._started = Date.now();
+    this._current = null;
+    this._previous = null;
+    this._lastScrobble = null;
+    this._pauseDuration = 0;
+  }
+
+  get id() {
+    return this._id;
+  }
+
+  get playing() {
+    return this._current;
+  }
+
+  set playing(value) {
+    this._current = value;
+  }
+
+  get started() {
+    return this._started;
+  }
+
+  get lastScrobbleTimestamp() {
+    return this._lastScrobble;
+  }
+
+  set lastScrobbleTimestamp(value) {
+    this._lastScrobble = value;
+  }
+
+  get pauseDuration() {
+    return this._pauseDuration;
+  }
+
+  set pauseDuration(value) {
+    this._pauseDuration = value;
+  }
+}
+
+module.exports = Session;

services/session-manager.js

@@ -0,0 +1,33 @@
+class SessionManager {
+  constructor() {
+    this._sessions = {};
+  }
+
+  add(session) {
+    if (!session || !session.id)
+      return;
+    
+    this._sessions[session.id] = session;
+  }
+
+  contains(sessionId) {
+    return this._sessions[sessionId] != null;
+  }
+
+  get(sessionId) {
+    return this._sessions[sessionId];
+  }
+
+  getSessionIds() {
+    return Object.keys(this._sessions);
+  }
+
+  remove(sessionId) {
+    if (!sessionId)
+      return;
+
+    delete this._sessions[sessionId];
+  }
+}
+
+module.exports = new SessionManager();