#ifndef COMMAND_H
#define COMMAND_H
///////////////////////////////////////////////////////////////
//  command.h  -  declare command and invoker classes        //
//  ver 1.0                                                  //
//  Lanuage:      Visual C++, ver 6.0                        //
//  Platform:     Micron Dual Pentium Pro 200, Win NT 4.0    //
//  Application:  CSE791 - Design Patterns Example           //
//  Author:       Jim Fawcett, Instructor                    //
//                CST 2-187, (315) 443-3948                  //
//                fawcett@ecs.syr.edu                        //
///////////////////////////////////////////////////////////////

#include <vector>

class command;

///////////////////////////////////////////////////////////////
//  invoker is usually some, perhaps large, library facility //
//  that generates events clients need to react to           //
///////////////////////////////////////////////////////////////

class invoker {

public:
  enum events { firstEv, secondEv, thirdEv };
  void Register(command*);
  void doCommands(events event);
  void doEvents();

private:
  std::vector<command*> registrants;
};

///////////////////////////////////////////////////////////////
//  command defines some interface for executing client code //
//  when one of perhaps several special events occurs        //
///////////////////////////////////////////////////////////////

class command {

public:
  virtual void execute(invoker::events event) = 0;
};

//

///////////////////////////////////////////////////////////////
//  this function will stay about the same for any library   //
///////////////////////////////////////////////////////////////

inline void invoker::Register(command* pComm) { 
  
  registrants.push_back(pComm);
}

///////////////////////////////////////////////////////////////
//  this function will stay about the same for any library   //
///////////////////////////////////////////////////////////////

inline void invoker::doCommands(events event) {

  unsigned int i;
  for(i=0; i<registrants.size(); i++)
    registrants[i]->execute(event);
}

///////////////////////////////////////////////////////////////
//  this function represents processing that will change for //
//  each library                                             //
///////////////////////////////////////////////////////////////

inline void invoker::doEvents() {

  doCommands(firstEv);
  doCommands(secondEv);
  doCommands(thirdEv);
}

#endif