/*  Basic Qt animation template by Chuck Liang, Hofstra University 
    Computer Science.

    This program may not be used in commercial software.
*/

// student will define animate function in a separate file

#include <qapplication.h>   
#include <qwidget.h>
#include <qpainter.h>
#include <qprinter.h>
#include <qpixmap.h>
#include <qmenubar.h>
#include <qpopupmenu.h>
#include <qcolor.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>

#define XBOUND 600
#define YBOUND 500


class mywindow : public QWidget     /* a template for a type of window */
{
Q_OBJECT

private:

  QPainter * brush;    /* an object that can do some graphics */
  QPainter * dbrush;   /* for drawing to the real screen */
  QPainter * pbrush;   // printing
  QPrinter printer;
  QPixmap * buffer;    // double buffer of animation and printing
  int proceed;         
  QMenuBar *menu;
  QPopupMenu *printop;

  void animate();  // to be defined by student

  void delay(int ms) // delay by ms milliseconds.
  {  struct timeval tv;
     tv.tv_sec = ms / 1000;
     ms = ms % 1000;
     tv.tv_usec = ms * 1000;
     select(0,NULL,NULL,NULL,&tv);
  }

  void clear()
  {
     brush->setBrush(QBrush(white,SolidPattern));  // clears buffer
     brush->drawRect(0,0,XBOUND,YBOUND);   // restart with white background
     brush->setBrush(QBrush(NoBrush));
  }

  void refresh()  // updates display
  {  
     brush->flush();
     dbrush->drawPixmap(0,0,*buffer);
     dbrush->flush();
  }


  /* a function that Qt expects to be defined: */
  void paintEvent(QPaintEvent *)   
  {  
    dbrush->begin(this);      // prepares the brush
    brush->begin(buffer);      // prepares the brush
    brush->setBrush(QBrush(white,SolidPattern));
    brush->drawRect(0,0,XBOUND,YBOUND);   // restart with white background
    brush->setBrush(QBrush(NoBrush));
    animate();
    brush->flush();
    //    bitBlt(buffer,0,0,this,0,0,XBOUND,YBOUND);  // printing
    brush->end();            // stops the "brush" session
    dbrush->end();            // stops the "brush" session
  }


public slots:

void printpic()
    {
  proceed = printer.setup();
    if (proceed) 
      {
      //      pbrush->setPen(red);  pbrush->drawEllipse(10,20,100,100); 
      pbrush->begin(&printer);
      pbrush->drawPixmap(0,0,*buffer);
      pbrush->end();
      }
    }  // end printpic

public:

  mywindow()      /* constructor for the window template */                 
  {  
    setGeometry(100, 100, XBOUND, YBOUND);  /* set position and size of program */
    brush = new QPainter;    // creates the brush object
    dbrush = new QPainter;    // creates the brush object
    pbrush = new QPainter;
    buffer = new QPixmap(XBOUND,YBOUND);
    /*  // no print menu in animation version of program
    menu = new QMenuBar(this);
    printop = new QPopupMenu();
    printop->insertItem("Print Pict", this, SLOT(printpic()));
    printop->insertItem("quit", qApp, SLOT(quit()));
    menu->insertItem("file",printop);
    */
  }

};


int main(int argc, char **argv)   // main is entry point of entire program
{ 
  QApplication theprogram(argc, argv);   // but the real program is a Qt one
  mywindow thewindow;                    // that uses a window!
  theprogram.setMainWidget(&thewindow);  // sets the main window
  thewindow.show();                      // shows and executes the Qt app.
  theprogram.exec();
  
  return 0;                              // exits gracefully
}