#include <stdlib.h>
#include <stdio.h>
#include <dos.h>
#include <conio.h>
#include "dg.h"
#include "listobj.h"
#include "app.h"

struct POINT
{
	int x,y;
	POINT( int x1 = 10, int y1= 10 ) { x=x1; y=y1; };
};

//
// Class ObjGraf - Imovel usado para Botoes
//
class Canvas;

class ObjGraf : public Obj
{
	public:
		virtual void click1(int, int, Canvas *cvAtivo)  {};// Tratadores de Evento
		virtual void unclick1(int, int, Canvas *cvAtivo){};// de cada Objeto Grafico
		virtual void click2(int, int, Canvas *cvAtivo)  {};
		virtual void unclick2(int, int, Canvas *cvAtivo){};
		virtual void move(int, int, Canvas *cvAtivo)    {};

		virtual void  draw(void)         = 0;    // Obgriga a definicao das
		virtual int   pick(int, int)     = 0;    // Funcoes comuns de Todos
															  // os Objetos Graficos
};

//
// Class Canvas
//
class Canvas : public List
{
	DgColor cor;
	ObjGraf *objGrafGrabbed; // Objeto Grafico bloqueado para receber Eventos

	ObjGraf *find(int, int);
	public:
		Canvas( DgColor c=dgLIGHT_GRAY ) { cor = c; objGrafGrabbed = NULL; }

		void     grab( ObjGraf *objGraf) { objGrafGrabbed = objGraf; }
		void     draw(void);
		void     redrawAll(void);
		void     click1(int x, int y);
		void     unclick1(int x, int y);
		void     move(int x, int y);
		void     insert(Obj*o) { List::insert(o); ((ObjGraf*)o)->draw(); }
};

void Canvas::draw( void )
{
	dgSetColor(cor);
	dgFill(0,0,dgWidth(),dgHeight());
}

void Canvas::redrawAll( void )
{
	ListIter *it = new ListIter( this );

	draw();
	it->last();
	while( ! it->end() )
	{
		((ObjGraf *)(it->prev()))->draw();
	}
}

ObjGraf* Canvas::find( int x, int y )
{
	ListIter *it = new ListIter( this );
	ObjGraf  *objGraf;

	it->first();
	while( ! it->end() )
	{
	  objGraf = (ObjGraf *)(it->next());
	  if( objGraf->pick(x,y) )
		 return( objGraf );
	}
	return NULL;
}

void Canvas :: click1(int x, int y)
{
  if( ! objGrafGrabbed )
  {
	 ObjGraf *objGraf = find(x,y);
	 if( objGraf )
		objGraf->click1(x, y, this);
  }
  else
  {
	 objGrafGrabbed->click1(x, y, this);
  }
}
void Canvas :: unclick1(int x, int y)
{
  if( ! objGrafGrabbed )
  {
	 ObjGraf *objGraf = find(x,y);
	 if( objGraf )
		objGraf->unclick1(x, y, this);
  }
  else
  {
	 objGrafGrabbed->unclick1(x, y, this);
  }
}

void Canvas :: move(int x, int y)
{
  if( ! objGrafGrabbed )
  {
	 ObjGraf *objGraf = find(x,y);
	 if( objGraf )
		objGraf->move(x, y, this);
  }
  else
  {
	 objGrafGrabbed->move(x, y, this);
  }
}

//
//  Class Botao
//
class Botao : public ObjGraf
{
	DgColor cor;
	POINT   p1,p2;   // Extremos do Rectangulo
	public:
		Botao(POINT x, POINT y, DgColor c) { p1=x; p2=y; cor=c; };
		virtual void click1(int x, int y, Canvas *cvAtivo) { action(cvAtivo); };
		virtual void draw(void);
		virtual int  pick(int x, int y);
		virtual void action(Canvas *) = 0;
};

void Botao :: draw(void)
{
	dgSetColor(dgYELLOW);
	dgSetMode(dgCOPY);
	dgFill(p1.x,p1.y,p2.x,p2.y);
	dgSetColor(cor);
	dgFill(p1.x+1,p1.y+1,p2.x-1,p2.y-1);
}

int Botao :: pick(int x, int y)
{
	if( (x >= p1.x) && (x <= p2.x ) &&
		 (y >= p1.y) && (y <= p2.y ) )
	  return 1;
	else
	  return 0;
}

//
//  Class BotaoOK
//
class BotaoOK : public Botao
{
	public:
		BotaoOK(POINT x, POINT y, DgColor c=dgLIGHT_CIAN) :Botao(x, y, c) {};
		virtual void action(Canvas *);
};

void BotaoOK :: action(Canvas *cvAtivo)
{
	printf( "\n\n Botao OK selecionado !!! ");
}
//
//  Class BotaoCANCEL
//
class BotaoCANCEL : public Botao
{
	public:
		BotaoCANCEL(POINT x, POINT y, DgColor c=dgLIGHT_CIAN) :Botao(x, y, c) {};
		virtual void action(Canvas *);
};

void BotaoCANCEL :: action(Canvas *cvAtivo)
{
	printf( "\n\n Botao CANCEL selecionado !!! ");
}

//
// Class ObjGrafM - Moveis usado para Retangulos, Triangulos, etc.
//
class ObjGrafM : public ObjGraf
{
	int arraste;
	int xAnt, yAnt;
	public:
		ObjGrafM() { arraste=0; }
		virtual void click1(int x, int y, Canvas *cvAtivo)
				  { arraste = 1;
					 dgSetMode(dgXOR);
					 draft();
					 xAnt=x; yAnt=y;
					 cvAtivo->grab(this);  // Bloqueia o Objeto Grafico
				  };
		virtual void unclick1(int x, int y, Canvas *cvAtivo )
				  { arraste = 0;
					 moveObj(x-xAnt, y-yAnt);
					 draft();
					 dgSetMode(dgCOPY);
					 cvAtivo->grab(NULL);  // DesBloqueia o Objeto Grafico
					 cvAtivo->redrawAll();
				  };
		virtual void move(int x, int y, Canvas *cvAtivo)
				  {
					 if( arraste )
					 {
						draft(); moveObj(x-xAnt, y-yAnt); xAnt= x; yAnt=y; draft();
					 }
				  };
		virtual void moveObj(int, int) = 0;  // Obriga a Redefinicao de move
		virtual void draft() { draw(); }
};
//
//       Rectangle
//
class Rectangle : public ObjGrafM
{
	DgColor cor;
	POINT   p1,p2;   // Extremos do Rectangulo
	public:
		Rectangle(POINT x, POINT y, DgColor c=dgRED) { p1=x; p2=y; cor=c; };
		void draw(void);
		void draft(void);
		int  pick(int x, int y);
		void moveObj(int x, int y);
};

void Rectangle :: draw(void)
{
	dgSetColor(cor);
	dgFill(p1.x,p1.y,p2.x,p2.y);
}

void Rectangle :: draft(void)
{
	dgSetColor(cor);
	dgRectangle(p1.x,p1.y,p2.x,p2.y);
}

int Rectangle :: pick(int x, int y)
{
	if( (x >= p1.x) && (x <= p2.x ) &&
		 (y >= p1.y) && (y <= p2.y ) )
	  return 1;
	else
	  return 0;
}

void Rectangle :: moveObj(int dx, int dy)
{
	p1.x += dx; p1.y += dy;
	p2.x += dx; p2.y += dy;
}

//
//       Triangle
//
class Triangle : public ObjGrafM
{
	DgColor cor;
	POINT   p1,p2,p3;   // Extremos do Triangulo
	public:
		Triangle(POINT x, POINT y, POINT z, DgColor c=dgRED) {p1=x; p2=y; p3=z; cor=c;};
		void  draw(void);
		void  draft(void);
		int   pick(int x, int y);
		void  moveObj(int x, int y);
};

void Triangle :: draw(void)
{
	dgSetColor(cor);
	dgBeginPoly();
	dgPolyPoint(p1.x, p1.y);
	dgPolyPoint(p2.x, p2.y);
	dgPolyPoint(p3.x, p3.y);
	dgEndPoly(dgFILL);
}

void Triangle :: draft(void)
{
	dgSetColor(cor);
	dgBeginPoly();
	dgPolyPoint(p1.x, p1.y);
	dgPolyPoint(p2.x, p2.y);
	dgPolyPoint(p3.x, p3.y);
	dgEndPoly(dgCLOSED);
}

int Triangle :: pick(int x, int y)
{
	int s    =p1.x*p2.y-p2.x*p1.y+p2.x*p3.y-p3.x*p2.y+p3.x*p1.y-p1.x*p3.y,
		 lamb1=   x*p2.y-p2.x*   y+p2.x*p3.y-p3.x*p2.y+p3.x*   y-   x*p3.y,
		 lamb2=p1.x*   y-   x*p1.y+   x*p3.y-p3.x*   y+p3.x*p1.y-p1.x*p3.y,
		 lamb3=p1.x*p2.y-p2.x*p1.y+p2.x*   y-   x*p2.y+   x*p1.y-p1.x*   y;
	if( s > 0 )
	  if( (lamb1>0) && (lamb2>0) && (lamb3>0) ) // Coordenadas Baricentricas
		 return 1;
	  else
		 return 0;
	else
	  if( (lamb1<0) && (lamb2<0) && (lamb3<0) ) // Coordenadas Baricentricas
		 return 1;
	  else
		 return 0;
}

void Triangle :: moveObj(int dx, int dy)
{
	p1.x += dx; p1.y += dy;
	p2.x += dx; p2.y += dy;
	p3.x += dx; p3.y += dy;
}


//
// Class MyApp
//
class MyApp : public Application
{
	public:
		Canvas cvAtivo;
		MyApp()
		{
		  dgOpen();
		  cvAtivo.draw();
		  BotaoOK bOK( POINT(10, 10), POINT(30, 30) );
		  cvAtivo.insert( &bOK );
		  BotaoCANCEL bCANCEL( POINT(10, 40), POINT(30, 60) );
		  cvAtivo.insert( &bCANCEL );
		  Rectangle r(POINT(100,100), POINT(120,150));
		  cvAtivo.insert( &r );
		  Triangle t(POINT(200,200), POINT(220,250), POINT(300,300));
		  cvAtivo.insert( &t );
		  loop();
		};
		void preLoop(void);
		void posLoop(void);
		//
		// Redespacha Tratamento de Eventos para o Canvas Ativo
		//
		void click1(int x, int y)   { cvAtivo.click1(x, y); }
		void unclick1(int x, int y) { cvAtivo.unclick1(x, y); }
		void click2(int x, int y)   { setFimLoop(); }
		void unclick2(int x, int y) { };
		void move(int x, int y)     { cvAtivo.move(x, y); }
};

void MyApp :: preLoop(void)
{
}

void MyApp :: posLoop(void)
{
	dgClose();
}

//
// Aplicacao
//
MyApp myApp;  // Observe que nao eh preciso o main

void main()
{
}