add code comments

program/Sources/amiunlocked/main.swift

@@ -3,13 +3,16 @@ import Configuration
 import Foundation
 import Just
 
+// Enumerate valid states for our computer: "locked" and "unlocked"
 enum State: String {
   case locked
   case unlocked
 }
 
-// Section: configuration
-
+// Section: Configuration
+// Start a configuration manager, load configuration from an adjacent
+// `config.json` file, cast config values to appropriate types, and
+// fail if required config values are not present
 let manager = ConfigurationManager()
 manager.load(file: "config.json")
 let url = manager["url"] as? String ?? ""
@@ -23,8 +26,9 @@ if writeKey == "" {
   fatalError("The config parameter 'writeKey' is required. Set it in 'config.json' and please try again.")
 }
 
-// Section: network requests
-
+// Section: Network Requests
+// Functions to create UTC timestamps and make network requests
+// to the kvdb bucket with a given `State`
 func getISOTimestamp() -> String {
   if #available(macOS 10.12, *) {
     let date = Date()
@@ -48,8 +52,10 @@ func sendRequest(state: State) {
   }
 }
 
-// Section: event listeners
-
+// Section: Event Listeners
+// The event listeners listening for `screenIsLocked` and `screenIsUnlocked`
+// events, and the callback function to log and make a network request in
+// response to a triggered event
 func logAndSendRequest(notification: Notification, state: State) {
   NSLog("Event: \(notification.name.rawValue)")
   sendRequest(state: state)