Added comments and regions for code clarity

Carol/Controls/HyperlinkTextField.cs

@@ -1,10 +1,21 @@
-using System;
+/*
+ * Custom Text field control that works as a hyperlink
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using System;
 using System.ComponentModel;
 using AppKit;
 using Foundation;
 
 namespace Carol.Controls
 {
+    // DesignTimeVisible(true) makes sure that the class is visible in Xcode at design time
     [Register("HyperlinkTextField"), DesignTimeVisible(true)]
     public class HyperlinkTextField : NSTextField
     {
@@ -23,6 +34,7 @@ public String Href
             set => href = value;
         }
 
+        #region Constructors
         public HyperlinkTextField(IntPtr p) : base(p)
         {
 
@@ -32,13 +44,15 @@ public HyperlinkTextField()
         {
 
         }
+        #endregion
 
         public override void AwakeFromNib()
         {
             base.AwakeFromNib();
 
             AttributedStringValue = new NSAttributedString(StringValue, new NSStringAttributes()
             {
+                //You can change the color of link after uncommenting the following
                 //ForegroundColor = NSColor.Blue,
                 UnderlineStyle = NSUnderlineStyle.Single.GetHashCode()
             });

Carol/Controls/PopoverView.cs

@@ -1,13 +1,26 @@
-using System;
+/*
+ * Custom Popover control with adjustable background color
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using System;
 using System.ComponentModel;
 using AppKit;
 using Foundation;
 
 namespace Carol.Controls
 {
+    // DesignTimeVisible(true) makes sure that the class is visible in Xcode at design time
     [Register("PopoverView"), DesignTimeVisible(true)]
     public class PopoverView : NSView
     {
+
+        #region Constructors
         public PopoverView()
         {
 
@@ -17,6 +30,7 @@ public PopoverView(IntPtr p) : base(p)
         {
 
         }
+        #endregion
 
         public override void ViewDidMoveToWindow()
         {
@@ -29,6 +43,8 @@ public override void ViewDidMoveToWindow()
                 {
                     WantsLayer = true
                 };
+
+                //You can change the background color of popover below. Here it takes the color as rgba
                 backgroundView.Layer.BackgroundColor = new CoreGraphics.CGColor(0.07f, 0.07f, 0.07f, 1.0f);
                 backgroundView.AutoresizingMask = (NSViewResizingMask.HeightSizable | NSViewResizingMask.WidthSizable);
                 frameView.AddSubview(backgroundView, NSWindowOrderingMode.Below, frameView);

Carol/Helpers/EventMonitor.cs

@@ -1,4 +1,14 @@
-using AppKit;
+/*
+ * Helper class to close the popover automatically on an external event
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using AppKit;
 using Foundation;
 namespace Carol.Helpers
 {
@@ -8,6 +18,7 @@ public class EventMonitor
         NSEventMask mask;
         GlobalEventHandler handler;
 
+        #region Constructors
         public EventMonitor()
         {
 
@@ -18,17 +29,25 @@ public EventMonitor(NSEventMask mask, GlobalEventHandler handler)
             this.mask = mask;
             this.handler = handler;
         }
+        #endregion
 
+        // Destructor
         ~EventMonitor()
         {
             Stop();
         }
 
+        /// <summary>
+        /// Start monitoring events of a given mask
+        /// </summary>
         public void Start()
         {
             monitor = NSEvent.AddGlobalMonitorForEventsMatchingMask(mask, handler) as NSObject;
         }
 
+        /// <summary>
+        /// Stop monitoring events and release the resources
+        /// </summary>
         public void Stop()
         {
             if (monitor != null)

Carol/Helpers/LyricsHelper.cs

@@ -1,4 +1,14 @@
-using System;
+/*
+ * Helper class to get the lyrics of a track
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using System;
 using System.Net.Http;
 using System.Threading.Tasks;
 using Carol.Models;
@@ -18,6 +28,12 @@ public LyricsHelper()
             apikey = SecretsReader.GetSecrets();
         }
 
+        /// <summary>
+        /// Method to get the track id of currently playing track
+        /// </summary>
+        /// <returns>Trackid.</returns>
+        /// <param name="track">Track Name.</param>
+        /// <param name="artist">Artist Name.</param>
 		public async Task GetTrackId(string track, string artist)
 		{
             var uri = new Uri(String.Format("https://api.musixmatch.com/ws/1.1/track.search?q_track={0}&q_artist={1}&apikey={2}", track, artist, apikey));
@@ -29,6 +45,13 @@ public async Task GetTrackId(string track, string artist)
 			}
 		}
 
+        /// <summary>
+        /// Method to get the lyrics of a track
+        /// </summary>
+        /// <returns>Lyrics of the track.</returns>
+        /// <param name="track">Track.</param>
+        /// <param name="artist">Artist.</param>
+        /// <param name="onSuccess">Action.</param>
         public async Task GetLyrics(string track, string artist, Action<string> onSuccess)
         {
             await GetTrackId(track, artist);

Carol/Helpers/SecretsReader.cs

@@ -1,4 +1,14 @@
-using System;
+/*
+ * Helper class to retrieve API key from Secrets.json fole
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using System;
 using System.IO;
 using Newtonsoft.Json.Linq;
 
@@ -8,6 +18,10 @@ public static class SecretsReader
     {
         private static JObject secrets;
 
+        /// <summary>
+        /// Gets the API key
+        /// </summary>
+        /// <returns>API Key</returns>
         public static string GetSecrets()
         {
             secrets = JObject.Parse(GetSecretKey());

Carol/Helpers/StatusBarController.cs

@@ -1,4 +1,14 @@
-using AppKit;
+/*
+ * Helper class to create and maintain a Status Bar Item
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using AppKit;
 using Foundation;
 
 namespace Carol.Helpers
@@ -14,6 +24,7 @@ public class StatusBarController : NSObject
         NSStoryboard storyboard;
         NSWindowController windowController;
 
+        #region Constructors
         public StatusBarController()
         { 
 
@@ -45,7 +56,9 @@ public StatusBarController(NSPopover popover, string image)
             storyboard = NSStoryboard.FromName("Main", null);
             windowController = storyboard.InstantiateControllerWithIdentifier("AboutWindow") as NSWindowController;
         }
+        #endregion
 
+        //Destructor
         ~StatusBarController()
         {
             ViewController.AboutMenuItemClicked -= HandleAboutMenuItemClicked;
@@ -73,12 +86,21 @@ void HidePopover(NSObject sender)
             eventMonitor.Stop();
         }
 
+        /// <summary>
+        /// Hides popover on external mouse click
+        /// </summary>
+        /// <param name="_event">Event.</param>
         void MouseEventHandler(NSEvent _event)
         {
             if (popover.Shown)
                 HidePopover(_event);
         }
 
+        /// <summary>
+        /// Handles the about menu item click.
+        /// </summary>
+        /// <param name="sender">Sender.</param>
+        /// <param name="e">E.</param>
         void HandleAboutMenuItemClicked(object sender, System.EventArgs e)
         {
             HidePopover(sender as NSObject);
@@ -91,6 +113,11 @@ void HandleAboutMenuItemClicked(object sender, System.EventArgs e)
             windowController.ShowWindow(sender as NSObject);
         }
 
+        /// <summary>
+        /// Handles the quit button click.
+        /// </summary>
+        /// <param name="sender">Sender.</param>
+        /// <param name="e">E.</param>
         void HandleQuitButtonClicked(object sender, System.EventArgs e)
         {
             HidePopover(sender as NSObject);

Carol/Models/TrackLyrics.cs

@@ -1,4 +1,14 @@
-using System;
+/*
+ * Model for lyrics of a track
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using System;
 using System.Collections.Generic;
 
 namespace Carol.Models

Carol/Models/Tracks.cs

@@ -1,4 +1,14 @@
-using System;
+/*
+ * Model for track
+ * 
+ * Author - Anagh Sharma
+ * http://www.anaghsharma.com
+ * 
+ * 2017
+ * 
+ */
+
+using System;
 using System.Collections.Generic;
 
 namespace Carol.Models