#include<stdio.h>
#include<stdlib.h>
#include<graphics.h>
#include<bios.h>
/*下面定义了一些控制命令*/
/*重画界面命令*/
#define CMDDRAW       5
/*消去一个满行的命令*/
#define CMDDELLINE    6
/*自动下移一行的命令*/
#define CMDAOTODOWN   7
/*生产新的方块*/
#define CMDGEN        8
/*向左移动的命令，以左箭头<-控制，它的ASCII码值是75*/
#define CMDLEFTMOVE   75
/*向右移动的命令，以右箭头->控制，它的ASCII码值是77*/
#define CMDRINGHTMOVE 77
/*旋转方块的命令，以空格来控制*/
#define CMDROTATE     57
/*向下移动的命令，以向下的箭头控制，它的ASCII码值是80*/
#define CMDDOWNMOVE   80
/*退出游戏的控制命令，以esc键控制，它的ASCII码值是1*/
#define CMDESC        1

/*定义了方块下降的时间间隔*/
#define TIMEINTERVAL  4

/*下面定义了游戏区的大小*/
#define MAXWIDTH      15
#define MAXHEIGHT          30
/*组成方块的小格子的宽度*/
#define BOXWIDTH      15

/*用两个数组来表示新旧两个矩形游戏区*/
int oldarea[MAXHEIGHT+1][MAXWIDTH];
int area[MAXHEIGHT+1][MAXWIDTH];
/*定义一个需要改变的屏幕区域，初次之外的区域不用进行重绘*/
int actW,actH,actX,actY;
/*当前方块的一些属性（坐标，颜色，高，宽）*/
int curX,curY,curColor,curW,curH;
/*新的方块的一些属性（坐标，颜色，高，宽）*/
int newX,newY,newColor,newW,newH;
/*制定方块的状态*/
int active;
/*存储当前方块的数组*/
int box[4][4];
/*当前方块的颜色*/
int BOXCOLOR;
/*控制命令*/
int CMD;
/*定义七种基本的方块形状*/
int BOX[7][4][4]={
 {{1,1,1,1},{0,0,0,0},{0,0,0,0},{0,0,0,0}},
 {{1,1,1,0},{1,0,0,0},{0,0,0,0},{0,0,0,0}},
 {{1,1,1,0},{0,0,1,0},{0,0,0,0},{0,0,0,0}},
 {{1,1,1,0},{0,1,0,0},{0,0,0,0},{0,0,0,0}},
 {{1,1,0,0},{0,1,1,0},{0,0,0,0},{0,0,0,0}},
 {{0,1,1,0},{1,1,0,0},{0,0,0,0},{0,0,0,0}},
 {{1,1,0,0},{1,1,0,0},{0,0,0,0},{0,0,0,0}}
};
/*得到方块的宽度，即从右向左第一个不空的列*/
int GetWidth()
{
    int i,j;
    for(i=3;i>0;i--)
    for(j=0;j<4;j++)
        if(box[j][i]) return i;
    return 0;
}
/*得到方块的高度，从上往下第一个不空的行*/
int GetHeight()
{
    int i,j;
     for(j=3;j>0;j--)
  for(i=0;i<4;i++)
       if(box[j][i]) return j;
     return 0;
}
/*清除原有的方块占有的空间*/
void ClearOldspace()
{
     int i,j;
     for(j=0;j<=curH; j++)
  for(i=0;i<=curW; i++)
       if(box[j][i])
        area[curY+j][curX+i]=0;
}
/*置位新方块的位置*/
void PutNewspace()
{
     int i,j;
     for(j=0;j<=newH;j++)
  for(i=0;i<=newW;i++)
       if(box[j][i])
        area[newY+j][newX+i]=BOXCOLOR;
}
/*判断方块的移动是否造成区域冲突*/
int MoveCollision(int box[][4])
{
     int i,j;
     if(newX<0) return 1;
     if(newX+newW>=MAXWIDTH) return 1;
     if(newY<0) return 1;
     for(j=0;j<=newH;j++)
      for(i=0;i<=newW;i++)
           if(area[newY+j][newX+i]&&box[j][i]) return 1;
     return 0;
}
/*判断翻转方块是否造成区域的冲突*/
int RotateBoxCollision(int box[][4])
{
     int i,j;
     if(newX+newW>=MAXWIDTH) newX=MAXWIDTH-1-newW;
     if(newY+newH>=MAXHEIGHT) newY=MAXHEIGHT-1-newH;
     if(MoveCollision(box)) return 1;
     for(i=0;i<=newW;i++)
      for(j=0;j<=newH;j++)
       if(area[newY+j][newX+i])
       {
        newX-=newW-i+1; goto L;
       }
     L: return MoveCollision(box);
}
/*游戏结束*/
int GameOver()
{
     if(!active &&(curY+curH>MAXHEIGHT-3))
         return 1;
     else
         return 0;
}
/*判断是否超时，即是否超过允许的时间间隔*/
int TimeOut()
{
     static long tm,old;
     tm=biostime(0,tm);
     if(tm-old<TIMEINTERVAL)
         return 0;
     else
     {
         old=tm;
         return 1;
     }
}
/*重绘游戏区*/
void DrawSpace()
{
     int row,col,x1,y1,x2,y2;
     for(row=actY;row<=actY+actH;row++)
  for(col=actX;col<=actX+actW;col++)
       if(area[row][col]!=oldarea[row][col])
       {
        if(area[row][col]==0)
             setfillstyle(SOLID_FILL,BLACK);
        else
             setfillstyle(SOLID_FILL,BOXCOLOR);
            x1=56+col*BOXWIDTH;
            x2=x1+BOXWIDTH;
        y1=464-(row+1)*BOXWIDTH;
        y2=y1+BOXWIDTH;
        bar(++x1,++y1,--x2,--y2);
        oldarea[row][col]=area[row][col];
      }
    CMD=0;
}
/*消去满行*/
void ClearFullline()
{
     int row,col, rowEnd,full,i,j;
     rowEnd=newY+newH;
     if(rowEnd>=MAXHEIGHT-1)
         rowEnd=MAXHEIGHT-2;
     for(row=newY; row<=rowEnd;)
     {
      full=1;
      for(col=0;col<MAXWIDTH;col++)
           if(!area[row][col])
               {full=0; break;}
      if(!full)
      {
          ++row;
          continue;
      }
      for(j=row; j<MAXHEIGHT-1;j++)
       for(i=0;i<MAXWIDTH;i++)
        area[j][i]=area[j+1][i];
      actX=0;
      actY=row;
      actW=MAXWIDTH-1;
      actH=MAXHEIGHT-1-row;
      DrawSpace();
      rowEnd--;
     }
     CMD=CMDGEN;
}
/*向左移动方块*/
int MoveLeft()
{
     newX=curX-1;
     ClearOldspace();
     if(MoveCollision(box))
     {
      newX=curX;
      PutNewspace();
      CMD=0;
      return 0;
     }
     PutNewspace();
     actW=curW+1;
     actX=curX=newX;
     CMD=CMDDRAW;
     return 1;
}
/*向右移动方块*/
int MoveRight()
{
     newX=curX+1; ClearOldspace();
     if(MoveCollision(box))
     {
          newX=curX;
          PutNewspace();
      CMD=0;
      return 0;
     }
     PutNewspace();
     actW=curW+1;
     actX=curX;
     curX=newX;
     CMD=CMDDRAW;
     return 1;
}
/*向下移动方块*/
int MoveDown()
{
     int i,j;
     newY=curY-1;
     ClearOldspace();
     if(MoveCollision(box))
     {
          newY=curY;
      PutNewspace();
      active=0;
      CMD=CMDDELLINE;
      return 0;
     }
     PutNewspace();
     actH=curH+1;
     actY=newY;
     curY=newY;
     CMD=CMDDRAW;
     return 1;
}
/*按加速键后方块迅速下落到底*/
void MoveBottom()
{
     while(active)
     {
          MoveDown();
          DrawSpace();
     }
     CMD=CMDDELLINE;
}
/*初始化*/
void InitialGame()
{
     int i,j,x1,y1,x2,y2;
     int driver=DETECT, mode=0;
     initgraph(&driver,&mode,"e:\\tc");
     cleardevice();
     randomize();
     setfillstyle(SOLID_FILL,BLUE);
     bar(0,0,639,479);
     x1=56;
     y1=464-BOXWIDTH*MAXHEIGHT;
     x2=56+MAXWIDTH*BOXWIDTH;
     y2=464;
     rectangle(--x1,--y1,++x2,++y2);
     setfillstyle(SOLID_FILL,BLACK);
     bar(++x1,++y1,--x2,--y2);
     y1=464-MAXHEIGHT*BOXWIDTH; y2=464;
     setcolor(DARKGRAY);
     for(i=0;i<MAXWIDTH;i++)
     {
      x1=56+i*BOXWIDTH;
      line(x1,y1,x1,y2);
     }
    x1=56; x2=x1+MAXWIDTH*BOXWIDTH;
     for(j=0;j<MAXHEIGHT;j++)
     {
      y1=464-j*BOXWIDTH;
          line(x1,y1,x2,y1);
     }
     for(j=0;j<MAXHEIGHT;j++)
  for(i=0;i<MAXWIDTH;i++)
       area[j][i]=oldarea[j][i]=0;
     actX=0; actY=0; actW=MAXWIDTH-1; actH=MAXHEIGHT-1;
     DrawSpace();
     CMD=CMDGEN;
}
/*得到控制命令*/
void GetCMD()
{
     if(CMD) return;
     if(TimeOut())
     {
      CMD=CMDAOTODOWN;
      return;
     }
     if(bioskey(1))
     {
      CMD=bioskey(0)>>8;
      return;
     }
}
/*生成一个新的方块*/
int GenerateNewbox()
{
 int i,j,boxidx;
 boxidx=random(7); BOXCOLOR=random(7)+1;
 for(j=0;j<4;j++)
  for(i=0;i<4;i++)
   box[j][i]=BOX[boxidx][j][i];
 curW=GetWidth(); curH=GetHeight();
 curX=(MAXWIDTH+curW)/2;
 if(curX+curW>=MAXWIDTH)curX=MAXWIDTH-1-curW;
 curY=MAXHEIGHT-1-curH;
 newX=curX; newY=curY; actX=curX;actY=curY;
 actW=newW=curW; actH=newH=curH;
 active=1;
 if(MoveCollision(box)) return 0;
 PutNewspace();
 DrawSpace(); CMD=0;
 return 1;
}
/*翻转方块*/
int RotateBox()
{
     int newBox[4][4];
     int i,j;
     ClearOldspace();
     for(j=0;j<4;j++)
  for(i=0;i<4;i++)
       newBox[j][i]=0;
     for(j=0;j<4;j++)
  for(i=0;i<4;i++)
       newBox[curW-i][j]=box[j][i];
     newW=curH;
     newH=curW;
     if(RotateBoxCollision(newBox))
     {
      newW=curW;
      newH=curH;
      newX=curX;
      newY=curY;
      PutNewspace();
      CMD=0;
      return 0;
     }
     for(j=0;j<4;j++)
  for(i=0;i<4;i++)
       box[j][i]=newBox[j][i];
     PutNewspace();
     actH=newH>curH? newH:curH;
     actW=curX+actH-newX;
     actX=newX;
     actY=newY;
     curX=newX;
     curY=newY;
     curW=newW;
     curH=newH;
     CMD=CMDDRAW;
     return 1;
}
/*根据获得的命令来执行不同的操作*/
void ExecuteCMD()
{
     switch(CMD)
     {
      case CMDLEFTMOVE:  
          MoveLeft();
          break;
      case CMDRINGHTMOVE:
          MoveRight();
          break;
      case CMDAOTODOWN:
          MoveDown();
          break;
      case CMDROTATE:
          RotateBox();
          break;
      case CMDDOWNMOVE:  
          MoveBottom();
          break;
      case CMDDRAW:  
          DrawSpace();
          break;
      case CMDDELLINE:  
          ClearFullline();
          break;
      case CMDGEN:   
          GenerateNewbox();
          break;
      case CMDESC:   
          closegraph();
          return 0;
      default:     
          CMD=0;
 }
}
/*主函数*/
int main()
{
     int i;
     InitialGame();
     do
     {
      GetCMD();
      ExecuteCMD();
     }
     while(!GameOver());
     getch();
     closegraph();
     return 0;
}