Implement conflict resolution protocol

1 files changed, 39 insertions, 4 deletions

diff --git a/src/ch/epfl/xblast/server/GameState.java b/src/ch/epfl/xblast/server/GameState.java
index e15f0bf..6e7f8c4 100644
--- a/src/ch/epfl/xblast/server/GameState.java
+++ b/src/ch/epfl/xblast/server/GameState.java
@@ -1,10 +1,7 @@
 package ch.epfl.xblast.server;
 
 import ch.epfl.cs108.Sq;
-import ch.epfl.xblast.ArgumentChecker;
-import ch.epfl.xblast.Cell;
-import ch.epfl.xblast.Direction;
-import ch.epfl.xblast.PlayerID;
+import ch.epfl.xblast.*;
 
 import java.util.*;
 import java.util.function.Function;
@@ -20,6 +17,20 @@ import java.util.stream.Stream;
 public final class GameState {
 
     /**
+     * The list of player priority order permutations.
+     */
+    private static final List<List<PlayerID>> PLAYER_PRIORITY_ORDERS = GameState.buildPlayerPriorityOrderList();
+
+    /**
+     * Builds and returns the player priority order permutations.
+     *
+     * @return the list of player priority orders
+     */
+    private static List<List<PlayerID>> buildPlayerPriorityOrderList() {
+        return Lists.permutations(Arrays.asList(PlayerID.values()));
+    }
+
+    /**
      * Filters the given list of players and returns the lively ones.
      *
      * @param players a list of players
@@ -261,4 +272,28 @@ public final class GameState {
         return null; // TODO
     }
 
+    /**
+     * Returns the current player priority order permutation.
+     *
+     * @return the player priority order
+     */
+    private List<PlayerID> currentPlayerPriorityOrder() {
+        int priorityIndex = this.ticks % GameState.PLAYER_PRIORITY_ORDERS.size();
+        return GameState.PLAYER_PRIORITY_ORDERS.get(priorityIndex);
+    }
+
+    /**
+     * Resolves a conflict according to the current priority order.
+     *
+     * @param claimants the list of claimants
+     * @return the highest priority player
+     */
+    private PlayerID resolveConflict(List<PlayerID> claimants) {
+        return this.currentPlayerPriorityOrder()
+                .stream()
+                .filter(claimants::contains)
+                .findFirst()
+                .get();
+    }
+
 }