express mode as enum, fix some display issues, use switch for mode checks

public.h

@@ -5,11 +5,13 @@
 
 using namespace std;
 
+typedef enum { NO_MODE = 0, SERVER_MODE = 1, CLIENT_MODE = 2 } chatmode_t;
+
+extern chatmode_t mode;
 extern const int PORT_NUM;
 extern string IP_ADDRESS;
 extern const int DEFAULT_CUR_X;
 extern const int DEFAULT_CUR_Y;
-extern int mode;
 extern int serverSocketDescriptor;
 extern int clientSocketDescriptor;
 extern struct timeval start1, end1;