Fix UUID handling better

src/main/kotlin/net/deliciousreya/minecraftportal/MinecraftPortalPlugin.kt

@@ -72,20 +72,29 @@ class MinecraftPortalPlugin() : JavaPlugin(), Listener
         } else {
             argsList[1]
         }
-        val playerString = when {
+        val playerString: String = when {
             argsList.size == 2 -> {
-                argsList[0]
+                val player = server.getPlayer(args[0])
+                player?.uniqueId?.toString()
+                    ?: try {
+                        UUID.fromString(args[0]).toString()
+                    } catch (ex: IllegalArgumentException) {
+                        "bad UUID"
+                    }
             }
             sender is Player -> {
                 sender.uniqueId.toString()
             }
             else -> {
-                null
+                "console"
             }
         }
-        if (playerString == null) {
+        if (playerString == "console") {
             sender.sendMessage("Only players can set their own color with the one-arg form.")
             return false
+        } else if (playerString == "bad UUID") {
+            sender.sendMessage("You must pass a UUID or the name of an online player.")
+            return false
         }
         if (colorString == "show") {
             if (sender is Player && playerString == sender.uniqueId.toString()) {
@@ -109,7 +118,8 @@ class MinecraftPortalPlugin() : JavaPlugin(), Listener
         if (sender is Player && playerString == sender.uniqueId.toString()) {
             sender.sendMessage("Your portals will now be marked with ${portals.getColorFor(playerString).name}.")
         } else {
-            sender.sendMessage("Portals created by $playerString will now be marked with ${portals.getColorFor(playerString).name}")
+            val name = server.getOfflinePlayer(UUID.fromString(playerString)).name
+            sender.sendMessage("Portals created by $name will now be marked with ${portals.getColorFor(playerString).name}")
         }
         return true
     }