Implemented donation alert. Resolves #44.

Author: andersfischernielsen

Traktor Transition Finder/DragDropViewController.swift

@@ -82,6 +82,7 @@ class DragDropViewController: NSViewController {
     }
 
     func selectSong(audioID: String) {
+        stateController?.incrementSelectedSongs()
         transitions = (graph?[audioID]?.1.map { edge in return edge })
 
         if (transitions != nil) {

Traktor Transition Finder/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.6</string>
+	<string>1.6.1</string>
 	<key>CFBundleVersion</key>
 	<string>1</string>
 	<key>LSApplicationCategoryType</key>

Traktor Transition Finder/SongToSongViewController.swift

@@ -47,6 +47,7 @@ class SongToSongViewController: NSViewController {
     }
 
     func selectSong(audioID: String, index: Int) {
+        stateController?.incrementSelectedSongs()
         guard index < 2 else { return }
         if let song = graph?[audioID]?.0 {
             if index == 0 { firstSong = song }

Traktor Transition Finder/StateController.swift

@@ -16,6 +16,11 @@ enum State {
     case Ready
 }
 
+enum DonationState {
+    case Donated
+    case Ignored
+}
+
 protocol StateSubscriber {
     func stateChanged(_ state: State) -> Void
 }
@@ -37,4 +42,43 @@ class StateController {
     func addListener(_ listener: StateSubscriber) {
         listeners.append(listener)
     }
+    
+    func incrementSelectedSongs() {
+        let before = UserDefaults.standard.integer(forKey: "selectedSongs")
+        UserDefaults.standard.set(before + 1, forKey: "selectedSongs")
+        checkDonationStatus()
+    }
+    
+    private func checkDonationStatus() {
+        func openDonateURL() {
+            let url = URL(string: "https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=ME8E22EZTC5G4&source=url")
+            NSWorkspace.shared.open(url!)
+        }
+        
+        let songCount = UserDefaults.standard.integer(forKey: "selectedSongs")
+        let donated = UserDefaults.standard.bool(forKey: "alreadyDonated")
+        if (songCount % 10 == 0 && !donated) {
+            let alert = NSAlert()
+            alert.messageText = "Please consider supporting the development of Traktor Transition Finder"
+            alert.informativeText = "Developing software takes time and ressources. \nPlease consider donating to support the development and improvement of Traktor Transition Finder."
+            alert.alertStyle = .informational
+            let alreadyDonatedButton = alert.addButton(withTitle: "I Have Already Donated")
+            let ignoreButton = alert.addButton(withTitle: "Ignore")
+            let donateButton = alert.addButton(withTitle: "Donate")
+            alreadyDonatedButton.keyEquivalent = ""
+            ignoreButton.keyEquivalent = "\033"
+            donateButton.keyEquivalent = "\r"
+            let response = alert.runModal()
+            if response == .alertThirdButtonReturn {
+                UserDefaults.standard.set(false, forKey: "alreadyDonated")
+                openDonateURL()
+            }
+            else if (response == .alertFirstButtonReturn) {
+                UserDefaults.standard.set(true, forKey: "alreadyDonated")
+            }
+            else {
+                UserDefaults.standard.set(false, forKey: "alreadyDonated")
+            }
+        }
+    }
 }