program snake;
uses crt;
var
   isPaused,newGame: boolean;
   opGO,op,dir,newD: char;
   cx,cy,tamc,pt,pt2,nv,nv2,perdeu: integer;
{cx,cx = posição da comida; tamc = tamanho da cobra; pt = pontos; pt2 = contador p/ mudar de nv; nv = nivel; nv2 velocidade}
   x,y: array[1..14] of integer;{posição das partes da cobra}

procedure pause;
var op,opt,p: char;

begin
   p:='0';
   sound(1000);
   delay(200);
   nosound;
   while (p='0') do
      begin
         textbackground(1);textcolor(7);
         gotoxy(30,10); write('É[Pausa]ÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»');
         gotoxy(30,11); write('º                     º');
         gotoxy(30,12); write('º [C] - Continuar     º');
         gotoxy(30,13); write('º [N] - Novo jogo     º');
         gotoxy(30,14); write('º [S] - Sair          º');
         gotoxy(30,15); write('º                     º');
         gotoxy(30,16); write('ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ');
         op:=upcase(readkey);
         if(op='C') then
           begin
              isPaused:=false;
              p:='1';
           end;
         if(op='N') then
           begin
              clrscr;
              writeln('Tem certeza que deseja iniciar um novo jogo? ([S]Sim / [N]Nao)');
              opt:=upcase(readkey);
              if(opt = 'S') then
                begin
                  clrscr;
                  randomize;
                  cx:=random(80); cy:=random(25); tamc:=3;
                  if (cy=1) then begin cy:=2; end;
                  perdeu:=0; dir:='D'; newD:='D'; x[1]:=4; y[1]:=2; pt:=0; pt2:=0; nv2:=80; nv:=1;
                  x[2]:=3; x[3]:=2; x[4]:=1; y[2]:=2; y[3]:=2; y[4]:=2;
                  textbackground(green);
                  gotoxy(1,1); write('                                                                               ');
                  gotoxy(2,1); write('Pontos: ',pt);
                  gotoxy(25,1); write('Nivel: ',nv);
                  isPaused:=false;
                  newGame := true;
                  p:='1';
                end;
              if(opt = 'N') then
                begin
                  isPaused:=false;
                  p:='1';
                end;
           end;
         if (op='S') then
           begin
             opGO:='N';
             p:='1';
             perdeu:=1;
           end;
      end;
end;

procedure tamanho;
begin
   if (tamc>2) then
     begin
        gotoxy(x[2],y[2]); write('O');
        gotoxy(x[3],y[3]); write('O');
        gotoxy(x[4],y[4]); write('O');
     end;
   if (tamc>4) then
     begin
        gotoxy(x[5],y[5]); write('O');
     end;
   if (tamc>5) then
     begin
        gotoxy(x[6],y[6]); write('O');
     end;
   if (tamc>6) then
     begin
        gotoxy(x[7],y[7]); write('O');
     end;
   if (tamc>7) then
     begin
        gotoxy(x[8],y[8]); write('O');
     end;
   if (tamc>8) then
     begin
        gotoxy(x[9],y[9]); write('O');
     end;
   if (tamc>9) then
     begin
        gotoxy(x[10],y[10]); write('O');
     end;
   if (tamc>10) then
     begin
        gotoxy(x[11],y[11]); write('O');
     end;
   if (tamc>11) then
     begin
        gotoxy(x[12],y[12]); write('O');
     end;
   if (tamc>12) then
     begin
        gotoxy(x[13],y[13]); write('O');
     end;
   if (tamc>13) then
     begin
        gotoxy(x[14],y[14]); write('O');
     end;
end;

procedure mov;
begin
   if (tamc=12) then
     begin
        x[14]:=x[13]; y[14]:=y[13];
     end;
   if (tamc>12) then
     begin
        x[13]:=x[12]; y[13]:=y[12];
     end;
   if (tamc>11) then
     begin
        x[12]:=x[11]; y[12]:=y[11];
     end;
   if (tamc>10) then
     begin
        x[11]:=x[10]; y[11]:=y[10];
     end;
   if (tamc>9) then
     begin
        x[10]:=x[9]; y[10]:=y[9];
     end;
   if (tamc>8) then
     begin
        x[9]:=x[8]; y[9]:=y[8];
     end;
   if (tamc>7) then
     begin
        x[8]:=x[7]; y[8]:=y[7];
     end;
   if (tamc>6) then
     begin
        x[7]:=x[6]; y[7]:=y[6];
     end;
   if (tamc>5) then
     begin
        x[6]:=x[5]; y[6]:=y[5];
     end;
   if (tamc>4) then
     begin
        x[5]:=x[4]; y[5]:=y[4];
     end;
end;

procedure inicio;
begin
   clrscr;
   randomize;
   cx:=random(80); cy:=random(25); tamc:=3;
   if (cy=1) then begin cy:=2; end;
   perdeu:=0; dir:='D'; newD:='D'; x[1]:=4; y[1]:=2; pt:=0; pt2:=0; nv2:=80; nv:=1;
   x[2]:=3; x[3]:=2; x[4]:=1; y[2]:=2; y[3]:=2; y[4]:=2;
   textbackground(green);
   tamanho;
   gotoxy(1,1); write('                                                                               ');
   gotoxy(2,1); write('Pontos: ',pt);
   gotoxy(25,1); write('Nivel: ',nv);
   while perdeu<>1 do
      begin
         clrscr;
         textbackground(0); textcolor(7);
         gotoxy(1,1); write('                                                                                ');
         gotoxy(2,1); write('Pontos: ',pt);
         gotoxy(25,1); write('Nivel: ',nv);
         textbackground(green);
         tamanho;
         gotoxy(x[1],y[1]); write('@');
         gotoxy(cx,cy); write('$');
         mov;
         x[4]:=x[3]; x[3]:=x[2]; x[2]:=x[1]; y[4]:=y[3]; y[3]:=y[2]; y[2]:=y[1];
         if (x[1]=cx)and(y[1]=cy) then
           begin
              randomize;
              cx:=random(80); cy:=random(25);
              if (cy=1) then begin cy:=2; end;
              sound(1000);
              delay(100);
              nosound;
              pt:=pt+10;
              pt2:=pt2+1;
              tamc:=tamc+1;
              textbackground(0);
              gotoxy(1,1); write('                                                                                ');
              gotoxy(2,1); write('Pontos: ',pt);
              gotoxy(25,1); write('Nivel: ',nv);
              textbackground(green);
           end;
         if keypressed then
           begin
             newD:=upcase(readkey);
            { label continue;}
             if (newD='W') and (dir<>'S') then {esta entrando aki mesmo se adir=s(aconte o mesmo nos outros)}
               begin
                 dir:='W';
               end;
             if (newD='S') and (dir<>'W') then
               begin
                 dir:='S';
               end;
             if (newD='A') and (dir<>'D') then
               begin
                 dir:='A';
               end;
             if (newD='D') and (dir<>'A') then
               begin
                 dir:='D';
               end;
             if (newD='#80') then
               begin
                 newD:=dir;
               end;
             if (newD='P') and (isPaused = false) then
               begin
                 isPaused:=true;
               end;
             if (newD<>'W')and(newD<>'S')and(newD<>'A')and(newD<>'D')and(newD<>'P') then
               begin
               newD:=dir;
               end;
           end;

          if (dir='W') then
            begin
              y[1]:=(y[1])-1;
            end;
          if (dir='S') then
            begin
              y[1]:=(y[1])+1;
            end;
          if (dir='A') then
            begin
              x[1]:=(x[1])-1;
            end;
          if (dir='D') then
            begin
              x[1]:=(x[1])+1;
            end;
          if (isPaused = true) then
            begin
              newD:=dir;
              pause;
            end;
           if (newD<>'W')and(newD<>'S')and(newD<>'A')and(newD<>'D')and(newD<>'P') then
             newD:=dir;
          if ((y[1])>25)or((x[1])>80)or((y[1])=1)or((x[1])=0) then {gameover}
            begin
              opGo:='S';
              newGame:=false;
              perdeu:=1;
            end;
          {Mudando de nivel}
          if (pt2=10) then
            begin
              textcolor(yellow);textbackground(0);
              clrscr;
              x[1]:=4; y[1]:=2; dir:='D'; newD:='D';
              x[2]:=3; x[3]:=2; x[4]:=1; y[2]:=2; y[3]:=2; y[4]:=2;
              nv2:=nv2-10;
              nv:=nv+1;
              tamc:=3;
              pt2:=0;
              gotoxy(35,12); write('Nivel ',nv);
              delay(3000);
            end;
          newD:=dir;
          delay(nv2);
      end;
end;

begin
  opGO:='S';
  clrscr;
  inicio;
  while opGO='S' do
    begin
      if(not(newGame)) then
        begin
          clrscr;
          writeln('GAME OVER');
          writeln('Deseja jogar novamente? ([S]Sim / [N]Nao)');
          op:=upcase(readkey);
          case (op) of
          'S':
            begin
              clrscr;
              inicio;
            end;
          'N':
            break;
          end;
        end
      else
        begin
          opGO:='N';
          inicio;
        end;
    end;
end.