#include <graphics.h>
#include <math.h>
#include <dos.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
#define N  100
#define molkol 3
char zarf[N][N];
struct mol
{
int x,y,size,vx,vy;
}m[molkol+1];
//===============================================
float fasele_oghlidosi(int x1,int y1,int x2,int y2)
{
return sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2));

}
//===============================================
int sign(int x)
{
if(x>0)
	return 1;
if(x<0)
	return -1;
return 0;
}
//===============================================
int barkhord(int sh_mol)
{
// barkhord
// 0 barkhord nakard 1 = barkhord kard be khate 1 khate paeen
if(m[sh_mol].y + 7 == N )
	{
	sound(1000);
	delay(100);
	nosound();
	return 1;
	}
if(m[sh_mol].y - 7 == 1 )
	{
	sound(1000);
	delay(100);
	nosound();
	return 2;
	}
if(m[sh_mol].x - 7 == 1 )
	{
	sound(1000);
	delay(100);
	nosound();
	return 3;
	}
if(m[sh_mol].x + 7 == N )
	{
	sound(1000);
	delay(100);
	nosound();
	return  4;
	}

return 0;
}
//===========================================
void keshidan_yek_mol(int x,int y)
{
for(int r = 7;r>=7;r--)
	{
	circle(x,y,r);
	}


}
//============================================
void barkhord_ba_divar()
{
for(int j =1; j<= molkol ; j++)
{
switch(barkhord(j))
{
// case 0:
// 	break;

case 1:
	{
	m[j].vy = m[j].vy * (-1);
	m[j].vx = m[j].vx;
	break;
	}
case 2 :
	{
	m[j].vy = m[j].vy * (-1);
	m[j].vx = m[j].vx;
	break;
	}
case 3 :
	{
	m[j].vy = m[j].vy;
	m[j].vx = m[j].vx * (-1);
	break;
	}
case 4 :
	{
	m[j].vy = m[j].vy;
	m[j].vx = m[j].vx * (-1);
	break;
	}
} // switch
} // for (int j
}
//===========================================
void clr()
{
setbkcolor(10);
cleardevice();
rectangle(0,0,N,N);
}
//============================================
int main(void)
{
int i,j;
   int gdriver = DETECT, gmode, errorcode;
   initgraph(&gdriver, &gmode, "f:\\software\\tc\\bgi\\");
   errorcode = graphresult();
   if (errorcode != grOk)  /* an error occurred */
   {
      printf("Graphics error: %s\n", grapherrormsg(errorcode));
      printf("Press any key to halt:");
      getch();
      exit(1);             /* return with error code */
   }
clr();
for(i=0;i<=N-1;i++)
	for(j=0;j<=N-1;j++)
		{
		zarf[i][j] = 0;
		}

m[1].x = 90;
m[1].y = 90;
m[1].vx = -1;
m[1].vy = 1;
keshidan_yek_mol(m[1].x,m[1].y);
zarf[m[1].x][m[1].y] = 1;

m[2].x = 85;
m[2].y = 15;
m[2].vx = 1;
m[2].vy = 1;
keshidan_yek_mol(m[2].x,m[2].y);
zarf[m[2].x][m[2].y] = 1;

m[3].x = 35;
m[3].y = 21;
m[3].vx = -1;
m[3].vy = 1;
keshidan_yek_mol(m[3].x,m[3].y);
zarf[m[3].x][m[3].y] = 1;
/*
m[4].x = 10;
m[4].y = 80;
m[4].vx = 0;
m[4].vy = -1;
keshidan_yek_mol(m[4].x,m[4].y);
zarf[m[4].x][m[4].y] = 1;

m[5].x = 135;
m[5].y = 110;
m[5].vx = 1;
m[5].vy = 1;
keshidan_yek_mol(m[5].x,m[5].y);
zarf[m[5].x][m[5].y] = 1;

m[6].x = 135;
m[6].y = 110;
m[6].vx = 0;
m[6].vy = 1;
keshidan_yek_mol(m[6].x,m[6].y);
zarf[m[6].x][m[6].y] = 1;

m[7].x = 115;
m[7].y = 145;
m[7].vx = -1;
m[7].vy = 0;
keshidan_yek_mol(m[7].x,m[7].y);
zarf[m[7].x][m[7].y] = 1;


  */









while(1)
{
	// move
	char ch = getch();
	if(ch == 27)
		return 0;
	clr();
	for (i=1;i<=molkol;i++)
		{
		zarf[m[i].x][m[i].y] = 0;
		m[i].x = m[i].vx *1 + m[i].x;
		m[i].y = m[i].vy *1 + m[i].y;
		zarf[m[i].x][m[i].y] = i;
		}
	for(i=1;i<= molkol;i++)
		keshidan_yek_mol(m[i].x,m[i].y);
/*
float r = sqrt(m[1].vx*m[1].vx + m[1].vy*m[1].vy);
float zavie1 = atan(m[1].vx/m[1].vy);
float teta = (zavie1 * 180)/3.141593;
float zavie_tagheer_masir = 90 - teta;
*/
barkhord_ba_divar();
// barkhord i ba j

for(i=1;i<= molkol  ;i++)
	{
	for(int j=i+1 ; j<= molkol; j++)
		{
		// fasele i ba j
		float fasele = fasele_oghlidosi(m[i].x,m[i].y,m[j].x,m[j].y);
		if(fasele<=14)
			{
			// barkhord az ro be ro ofoghi
			if((sign(m[i].vx) != sign(m[j].vx) )&&( sign(m[i].vy) ==0 )&&( sign(m[j].vy== 0 )))
				{
				m[i].vx = m[i].vx * (-1);
				m[j].vx = m[j].vx * (-1);
				}
			// barkhord az ro be ro amodi
			if((sign(m[i].vy) != sign(m[j].vy) )&&( sign(m[i].vx) ==0 )&&( sign(m[j].vx== 0 )))
				{
				m[i].vy = m[i].vy * (-1);
				m[j].vy = m[j].vy * (-1);
				}
			//
			if( (sign(m[i].vx) == sign(m[j].vx)) &&(sign(m[j].vx) !=0))
				{
				m[i].vy = m[i].vy * (-1);
				m[j].vy = m[j].vy * (-1);
				}
			if( (sign(m[i].vy) == sign(m[j].vy)) &&(sign(m[j].vy) !=0))

				{
				m[i].vx = m[i].vx * (-1);
				m[j].vx = m[j].vx * (-1);
				}
			// barkhord zarb dari
			if((sign(m[i].vy) != sign(m[j].vy) )&&(sign(m[i].vx) != sign(m[j].vx) ))
				{
				m[i].vx = m[i].vx * (-1);
				m[i].vy = m[i].vy * (-1);

				m[j].vx = m[j].vx * (-1);
				m[j].vy = m[j].vy * (-1);
				}






			}
		}
	}
} //while
getch();
closegraph();
return 0;
}