add some argument types

velocity/site/lab0x13/scrow/commands/velocity/suggestionprovider/PlayerSuggestionProvider.java

@@ -0,0 +1,24 @@
+package suggestionprovider;
+
+import com.velocitypowered.api.proxy.Player;
+import com.velocitypowered.api.proxy.ProxyServer;
+import site.lab0x13.scrow.commands.model.CommandContext;
+import site.lab0x13.scrow.commands.model.SuggestionProvider;
+
+import java.util.List;
+
+public final class PlayerSuggestionProvider<C extends CommandContext<C>> implements SuggestionProvider<C> {
+
+    private final ProxyServer proxyServer;
+
+    public PlayerSuggestionProvider(ProxyServer proxyServer) {
+        this.proxyServer = proxyServer;
+    }
+
+    @Override
+    public List<String> suggest(C __, String ___) {
+        return proxyServer.getAllPlayers().stream()
+                .map(Player::getUsername)
+                .toList();
+    }
+}

velocity/site/lab0x13/scrow/commands/velocity/type/PlayerArgumentType.java

@@ -0,0 +1,43 @@
+package type;
+
+import com.leakyabstractions.result.api.Result;
+import com.leakyabstractions.result.core.Results;
+import com.velocitypowered.api.command.CommandSource;
+import com.velocitypowered.api.proxy.Player;
+import com.velocitypowered.api.proxy.ProxyServer;
+import site.lab0x13.scrow.commands.model.CommandContext;
+import site.lab0x13.scrow.commands.model.SuggestionProvider;
+import site.lab0x13.scrow.commands.model.argument.ArgumentType;
+import suggestionprovider.PlayerSuggestionProvider;
+
+import java.util.UUID;
+
+public class PlayerArgumentType<C extends CommandSource & CommandContext<C>> implements ArgumentType<C, Player> {
+
+    private final ProxyServer server;
+
+    public PlayerArgumentType(ProxyServer server) {
+        this.server = server;
+    }
+
+    @Override
+    public Result<Player, String> parseInput(String input) {
+        Player player;
+        if (input.length() == 36) {
+            try {
+                player = server.getPlayer(UUID.fromString(input)).orElse(null);
+            } catch (IllegalArgumentException _) {
+                return Results.failure("Invalid UUID.");
+            }
+        } else {
+            player = server.getPlayer(input).orElse(null);
+        }
+
+        return Results.ofNullable(player, "Player not online.");
+    }
+
+    @Override
+    public SuggestionProvider<C> defaultSuggestionProvider() {
+        return new PlayerSuggestionProvider<>(server);
+    }
+}