End of chapter 6. A lot of problems took to much time to solve. It was good to know better Godot internal mechanism.

scripts/game/commands/MoveCommand.gd

@@ -0,0 +1,22 @@
+extends Command
+
+class_name MoveCommand
+
+var direction
+
+func _init(dir):
+	commandLabel = "Move"
+	direction = dir
+
+
+func execute():
+	CommandDispatcher.PLAYER_MOVE.emit(direction)
+	emit_signal("COMMAND_PROCESSED", getCommandText())
+
+
+func getDirectionString() -> String:
+	return Map.Direction.keys()[direction]
+
+
+func getCommandText():
+	return "%s %s" % [commandLabel, getDirectionString()]