Add Leaderboard managing methods

GoldWars/GoldWars/GameCenterManager.swift

@@ -109,6 +109,77 @@ final class GameCenterManager: NSObject, GKMatchmakerViewControllerDelegate, GKG
         }
     }
     
+    func submitLeaderboardScore(identifier: String, score: Int64) {
+        let reportedScore = GKScore(leaderboardIdentifier: identifier)
+        reportedScore.value = score
+        GKScore.report([reportedScore]) { (error) in
+            guard error == nil else {
+                print(error?.localizedDescription ?? "")
+                return
+            }
+        }
+    }
+    
+    func calculateLeaderboardScore(identifier: String, scoreOffset: Int64) {
+        GKLeaderboard.loadLeaderboards { (leaderboards: [GKLeaderboard]?, err: Error?) in
+            leaderboards?.forEach({ (leaderboard: GKLeaderboard) in
+                if leaderboard.identifier == identifier {
+                    leaderboard.loadScores { (scores: [GKScore]?, err: Error?) in
+                        scores?.forEach({ (score: GKScore) in
+                            if score.player == self.localPlayer {
+                                score.value += scoreOffset
+                                GKScore.report([score]) { (error) in
+                                    guard error == nil else {
+                                        print(error?.localizedDescription ?? "")
+                                        return
+                                    }
+                                }
+                            }
+                        })
+                    }
+                }
+            })
+        }
+    }
+    
+    //TODO: not finished -> DELETE if not usefull
+    // Possible way to implement matchmaking based on 2 players
+    // can be changed into method with fixed leaderboard and offset, boolean hasWon: true/false to calculate outcome of a match
+    func calculateLeaderboardScoreExperimentalMatchmaking(identifier: String, scoreOffset: Int64, opponentPlayer: GKPlayer) {
+        // Iterate through leaderboards
+        GKLeaderboard.loadLeaderboards { (leaderboards: [GKLeaderboard]?, err: Error?) in
+            leaderboards?.forEach({ (leaderboard: GKLeaderboard) in
+                if leaderboard.identifier == identifier {
+                    leaderboard.loadScores { (scores: [GKScore]?, err: Error?) in
+                        // Iterate through scores
+                        var currentScore: GKScore = GKScore.init()
+                        currentScore.value = -1
+                        var opponetScore: GKScore = GKScore.init()
+                        currentScore.value = 0
+                        // Get scores of self and opponent
+                        scores?.forEach({ (score: GKScore) in
+                            if score.player == self.localPlayer {
+                                currentScore = score
+                                opponetScore = score
+                            }
+                            if score.player == opponentPlayer {
+                                opponetScore = score
+                            }
+                        })
+                        // do silly calculation
+                        currentScore.value += scoreOffset + (opponetScore.value - currentScore.value)
+                        GKScore.report([currentScore]) { (error) in
+                            guard error == nil else {
+                                print(error?.localizedDescription ?? "")
+                                return
+                            }
+                        }
+                    }
+                }
+            })
+        }
+    }
+        
     func match(_ match: GKMatch, didReceive data: Data, fromRemotePlayer player: GKPlayer) {
         if myMatch != match { return }
         let jsonDecoder = JSONDecoder()