俄罗斯方块

#!/bin/bash

APP_NAME="${0##*[\\/]}"
APP_VERSION="1.0"

#颜色定义
cRed=1
cGreen=2
cYellow=3
cBlue=4
cFuchsia=5
cCyan=6
cWhite=7
colorTable=($cRed $cGreen $cYellow $cBlue $cFuchsia $cCyan $cWhite)

#位置和大小
iLeft=3
iTop=2
((iTrayLeft = iLeft + 2))
((iTrayTop = iTop + 1))
((iTrayWidth = 10))
((iTrayHeight = 15))

#颜色设置
cBorder=$cGreen
cScore=$cFuchsia
cScoreValue=$cCyan

#控制信号
#改游戏使用两个进程，一个用于接收输入，一个用于游戏流程和显示界面;
#当前者接收到上下左右等按键时，通过向后者发送signal的方式通知后者。
sigRotate=25
sigLeft=26
sigRight=27
sigDown=28
sigAllDown=29
sigExit=30

#七中不同的方块的定义
#通过旋转，每种方块的显示的样式可能有几种
box0=(0 0 0 1 1 0 1 1)
box1=(0 2 1 2 2 2 3 2 1 0 1 1 1 2 1 3)
box2=(0 0 0 1 1 1 1 2 0 1 1 0 1 1 2 0)
box3=(0 1 0 2 1 0 1 1 0 0 1 0 1 1 2 1)
box4=(0 1 0 2 1 1 2 1 1 0 1 1 1 2 2 2 0 1 1 1 2 0 2 1 0 0 1 0 1 1 1 2)
box5=(0 1 1 1 2 1 2 2 1 0 1 1 1 2 2 0 0 0 0 1 1 1 2 1 0 2 1 0 1 1 1 2)
box6=(0 1 1 1 1 2 2 1 1 0 1 1 1 2 2 1 0 1 1 0 1 1 2 1 0 1 1 0 1 1 1 2)
#所有其中方块的定义都放到box变量中
box=(${box0[@]} ${box1[@]} ${box2[@]} ${box3[@]} ${box4[@]} ${box5[@]} ${box6[@]})
#各种方块旋转后可能的样式数目
countBox=(1 2 2 2 4 4 4)
#各种方块再box数组中的偏移
offsetBox=(0 1 3 5 7 11 15)

#每提高一个速度级需要积累的分数
iScoreEachLevel=50 #be greater than 7

#运行时数据
sig=0           #接收到的signal
iScore=0        #总分
iLevel=0        #速度级
boxNew=()       #新下落的方块的位置定义
cBoxNew=0       #新下落的方块的颜色
iBoxNewType=0   #新下落的方块的种类
iBoxNewRotate=0 #新下落的方块的旋转角度
boxCur=()       #当前方块的位置定义
cBoxCur=0       #当前方块的颜色
iBoxCurType=0   #当前方块的种类
iBoxCurRotate=0 #当前方块的旋转角度
boxCurX=-1      #当前方块的x坐标位置
boxCurY=-1      #当前方块的y坐标位置
iMap=()         #背景方块图表

#初始化所有背景方块为-1, 表示没有方块
for ((i = 0; i < iTrayHeight * iTrayWidth; i++)); do iMap[$i]=-1; done

#接收输入的进程的主函数
function RunAsKeyReceiver() {
  local pidDisplayer key aKey sig cESC sTTY

  pidDisplayer=$1
  aKey=(0 0 0)

  cESC=$(echo -ne "\033")
  cSpace=$(echo -ne "\040")

  #保存终端属性。在read -s读取终端键时，终端的属性会被暂时改变。
  #如果在read -s时程序被不幸杀掉，可能会导致终端混乱，
  #需要在程序退出时恢复终端属性。
  sTTY=$(stty -g)

  #捕捉退出信号
  trap "MyExit;" INT TERM
  trap "MyExitNoSub;" $sigExit

  #隐藏光标
  echo -ne "\033[?25l"

  while :; do
    #读取输入。注-s不回显，-n读到一个字符立即返回
    read -s -n 1 key

    aKey[0]=${aKey[1]}
    aKey[1]=${aKey[2]}
    aKey[2]=$key
    sig=0

    #判断输入了何种键
    if [[ $key == $cESC && ${aKey[1]} == $cESC ]]; then
      #ESC键
      MyExit
    elif [[ ${aKey[0]} == $cESC && ${aKey[1]} == "[" ]]; then
      if [[ $key == "A" ]]; then
        sig=$sigRotate #<向上键>
      elif [[ $key == "B" ]]; then
        sig=$sigDown #<向下键>
      elif [[ $key == "D" ]]; then
        sig=$sigLeft #<向左键>
      elif [[ $key == "C" ]]; then
        sig=$sigRight #<向右键>
      fi
    elif [[ $key == "W" || $key == "w" ]]; then
      sig=$sigRotate #W, w
    elif [[ $key == "S" || $key == "s" ]]; then
      sig=$sigDown #S, s
    elif [[ $key == "A" || $key == "a" ]]; then
      sig=$sigLeft #A, a
    elif [[ $key == "D" || $key == "d" ]]; then
      sig=$sigRight #D, d
    elif [[ "[$key]" == "[]" ]]; then
      sig=$sigAllDown #空格键
    elif [[ $key == "Q" || $key == "q" ]]; then #Q, q
      MyExit
    fi

    if [[ $sig != 0 ]]; then
      #向另一进程发送消息
      kill -$sig $pidDisplayer
    fi
  done
}

#退出前的恢复
function MyExitNoSub() {
  local y

  #恢复终端属性
  stty $sTTY
  ((y = iTop + iTrayHeight + 4))

  #显示光标
  echo -e "\033[?25h\033[${y};0H"
  exit
}

function MyExit() {
  #通知显示进程需要退出
  kill -$sigExit $pidDisplayer
  MyExitNoSub
}

#处理显示和游戏流程的主函数
function RunAsDisplayer() {
  local sigThis
  InitDraw

  #挂载各种信号的处理函数
  trap "sig=$sigRotate;" $sigRotate
  trap "sig=$sigLeft;" $sigLeft
  trap "sig=$sigRight;" $sigRight
  trap "sig=$sigDown;" $sigDown
  trap "sig=$sigAllDown;" $sigAllDown
  trap "ShowExit;" $sigExit

  while :; do
    #根据当前的速度级iLevel不同，设定相应的循环的次数
    for ((i = 0; i < 21 - iLevel; i++)); do
      sleep 0.02
      sigThis=$sig
      sig=0

      #根据sig变量判断是否接受到相应的信号
      if ((sigThis == sigRotate)); then
        BoxRotate #旋转
      elif ((sigThis == sigLeft)); then
        BoxLeft #左移一列
      elif ((sigThis == sigRight)); then
        BoxRight #右移一列
      elif ((sigThis == sigDown)); then
        BoxDown #下落一行
      elif ((sigThis == sigAllDown)); then
        BoxAllDown #下落到底
      fi
    done
    #kill -$sigDown $
    BoxDown #下落一行
  done
}

#BoxMove(y, x), 测试是否可以把移动中的方块移到(x, y)的位置, 返回0则可以, 1不可以
function BoxMove() {
  local j i x y xTest yTest
  yTest=$1
  xTest=$2
  for ((j = 0; j < 8; j += 2)); do
    ((i = j + 1))
    ((y = ${boxCur[$j]} + yTest))
    ((x = ${boxCur[$i]} + xTest))
    if ((y < 0 || y >= iTrayHeight || x < 0 || x >= iTrayWidth)); then
      #撞到墙壁了
      return 1
    fi
    if ((${iMap[y * iTrayWidth + x]} != -1)); then
      #撞到其他已经存在的方块了
      return 1
    fi
  done
  return 0
}

#将当前移动中的方块放到背景方块中去,
#并计算新的分数和速度级。(即一次方块落到底部)
function Box2Map() {
  local j i x y xp yp line

  #将当前移动中的方块放到背景方块中去
  for ((j = 0; j < 8; j += 2)); do
    ((i = j + 1))
    ((y = ${boxCur[$j]} + boxCurY))
    ((x = ${boxCur[$i]} + boxCurX))
    ((i = y * iTrayWidth + x))
    iMap[$i]=$cBoxCur
  done

  #消去可被消去的行
  line=0
  for ((j = 0; j < iTrayWidth * iTrayHeight; j += iTrayWidth)); do
    for ((i = j + iTrayWidth - 1; i >= j; i--)); do
      if ((${iMap[$i]} == -1)); then break; fi
    done
    if ((i >= j)); then continue; fi

    ((line++))
    for ((i = j - 1; i >= 0; i--)); do
      ((x = i + iTrayWidth))
      iMap[$x]=${iMap[$i]}
    done
    for ((i = 0; i < iTrayWidth; i++)); do
      iMap[$i]=-1
    done
  done

  if ((line == 0)); then return; fi

  #根据消去的行数line计算分数和速度级
  ((x = iLeft + iTrayWidth * 2 + 7))
  ((y = iTop + 11))
  ((iScore += line * 2 - 1))
  #显示新的分数
  echo -ne "\033[1m\033[3${cScoreValue}m\033[${y};${x}H${iScore}         "
  if ((iScore % iScoreEachLevel < line * 2 - 1)); then
    if ((iLevel < 20)); then
      ((iLevel++))
      ((y = iTop + 14))
      #显示新的速度级
      echo -ne "\033[3${cScoreValue}m\033[${y};${x}H${iLevel}        "
    fi
  fi
  echo -ne "\033[0m"

  #重新显示背景方块
  for ((y = 0; y < iTrayHeight; y++)); do
    ((yp = y + iTrayTop + 1))
    ((xp = iTrayLeft + 1))
    ((i = y * iTrayWidth))
    echo -ne "\033[${yp};${xp}H"
    for ((x = 0; x < iTrayWidth; x++)); do
      ((j = i + x))
      if ((${iMap[$j]} == -1)); then
        echo -ne "  "
      else
        echo -ne "\033[1m\033[7m\033[3${iMap[$j]}m\033[4${iMap[$j]}m[]\033[0m"
      fi
    done
  done
}

#下落一行
function BoxDown() {
  local y s
  ((y = boxCurY + 1)) #新的y坐标
  if BoxMove $y $boxCurX; then #测试是否可以下落一行
    s="$(DrawCurBox 0)" #将旧的方块抹去
    ((boxCurY = y))
    s="$s$(DrawCurBox 1)" #显示新的下落后方块
    echo -ne $s
  else
    #走到这儿, 如果不能下落了
    Box2Map   #将当前移动中的方块贴到背景方块中
    RandomBox #产生新的方块
  fi
}

#左移一列
function BoxLeft() {
  local x s
  ((x = boxCurX - 1))
  if BoxMove $boxCurY $x; then
    s=$(DrawCurBox 0)
    ((boxCurX = x))
    s=$s$(DrawCurBox 1)
    echo -ne $s
  fi
}

#右移一列
function BoxRight() {
  local x s
  ((x = boxCurX + 1))
  if BoxMove $boxCurY $x; then
    s=$(DrawCurBox 0)
    ((boxCurX = x))
    s=$s$(DrawCurBox 1)
    echo -ne $s
  fi
}

#下落到底
function BoxAllDown() {
  local k j i x y iDown s
  iDown=$iTrayHeight

  #计算一共需要下落多少行
  for ((j = 0; j < 8; j += 2)); do
    ((i = j + 1))
    ((y = ${boxCur[$j]} + boxCurY))
    ((x = ${boxCur[$i]} + boxCurX))
    for ((k = y + 1; k < iTrayHeight; k++)); do
      ((i = k * iTrayWidth + x))
      if ((${iMap[$i]} != -1)); then break; fi
    done
    ((k -= y + 1))
    if (($iDown > $k)); then iDown=$k; fi
  done

  s=$(DrawCurBox 0) #将旧的方块抹去
  ((boxCurY += iDown))
  s=$s$(DrawCurBox 1) #显示新的下落后的方块
  echo -ne $s
  Box2Map   #将当前移动中的方块贴到背景方块中
  RandomBox #产生新的方块
}

#旋转方块
function BoxRotate() {
  local iCount iTestRotate boxTest j i s
  iCount=${countBox[$iBoxCurType]} #当前的方块经旋转可以产生的样式的数目

  #计算旋转后的新的样式
  ((iTestRotate = iBoxCurRotate + 1))
  if ((iTestRotate >= iCount)); then
    ((iTestRotate = 0))
  fi

  #更新到新的样式, 保存老的样式(但不显示)
  for ((j = 0, i = (${offsetBox[$iBoxCurType]} + $iTestRotate) * 8; j < 8; j++, i++)); do
    boxTest[$j]=${boxCur[$j]}
    boxCur[$j]=${box[$i]}
  done

  if BoxMove $boxCurY $boxCurX; then #测试旋转后是否有空间放的下
    #抹去旧的方块
    for ((j = 0; j < 8; j++)); do
      boxCur[$j]=${boxTest[$j]}
    done
    s=$(DrawCurBox 0)

    #画上新的方块
    for ((j = 0, i = (${offsetBox[$iBoxCurType]} + $iTestRotate) * 8; j < 8; j++, i++)); do
      boxCur[$j]=${box[$i]}
    done
    s=$s$(DrawCurBox 1)
    echo -ne $s
    iBoxCurRotate=$iTestRotate
  else
    #不能旋转，还是继续使用老的样式
    for ((j = 0; j < 8; j++)); do
      boxCur[$j]=${boxTest[$j]}
    done
  fi
}

#DrawCurBox(bDraw), 绘制当前移动中的方块, bDraw为1, 画上, bDraw为0, 抹去方块。
function DrawCurBox() {
  local i j t bDraw sBox s
  bDraw=$1

  s=""
  if ((bDraw == 0)); then
    sBox="\040\040"
  else
    sBox="[]"
    s=$s"\033[1m\033[7m\033[3${cBoxCur}m\033[4${cBoxCur}m"
  fi

  for ((j = 0; j < 8; j += 2)); do
    ((i = iTrayTop + 1 + ${boxCur[$j]} + boxCurY))
    ((t = iTrayLeft + 1 + 2 * (boxCurX + ${boxCur[$j + 1]})))
    #\033[y;xH, 光标到(x, y)处
    s=$s"\033[${i};${t}H${sBox}"
  done
  s=$s"\033[0m"
  echo -n $s
}

#更新新的方块
function RandomBox() {
  local i j t

  #更新当前移动的方块
  iBoxCurType=${iBoxNewType}
  iBoxCurRotate=${iBoxNewRotate}
  cBoxCur=${cBoxNew}
  for ((j = 0; j < ${#boxNew[@]}; j++)); do
    boxCur[$j]=${boxNew[$j]}
  done

  #显示当前移动的方块
  if ((${#boxCur[@]} == 8)); then
    #计算当前方块该从顶端哪一行"冒"出来
    for ((j = 0, t = 4; j < 8; j += 2)); do
      if ((${boxCur[$j]} < t)); then t=${boxCur[$j]}; fi
    done
    ((boxCurY = -t))
    for ((j = 1, i = -4, t = 20; j < 8; j += 2)); do
      if ((${boxCur[$j]} > i)); then i=${boxCur[$j]}; fi
      if ((${boxCur[$j]} < t)); then t=${boxCur[$j]}; fi
    done
    ((boxCurX = (iTrayWidth - 1 - i - t) / 2))

    #显示当前移动的方块
    echo -ne $(DrawCurBox 1)

    #如果方块一出来就没处放，Game over!
    if ! BoxMove $boxCurY $boxCurX; then
      kill -$sigExit ${PPID}
      ShowExit
    fi
  fi

  #清除右边预显示的方块
  for ((j = 0; j < 4; j++)); do
    ((i = iTop + 1 + j))
    ((t = iLeft + 2 * iTrayWidth + 7))
    echo -ne "\033[${i};${t}H        "
  done

  #随机产生新的方块
  ((iBoxNewType = RANDOM % ${#offsetBox[@]}))
  ((iBoxNewRotate = RANDOM % ${countBox[$iBoxNewType]}))
  for ((j = 0, i = (${offsetBox[$iBoxNewType]} + $iBoxNewRotate) * 8; j < 8; j++, i++)); do
    boxNew[$j]=${box[$i]}
  done

  ((cBoxNew = ${colorTable[RANDOM % ${#colorTable[@]}]}))

  #显示右边预显示的方块
  echo -ne "\033[1m\033[7m\033[3${cBoxNew}m\033[4${cBoxNew}m"
  for ((j = 0; j < 8; j += 2)); do
    ((i = iTop + 1 + ${boxNew[$j]}))
    ((t = iLeft + 2 * iTrayWidth + 7 + 2 * ${boxNew[$j + 1]}))
    echo -ne "\033[${i};${t}H[]"
  done
  echo -ne "\033[0m"
}

#初始绘制
function InitDraw() {
  clear
  RandomBox #随机产生方块，这时右边预显示窗口中有方快了
  RandomBox #再随机产生方块，右边预显示窗口中的方块被更新，原先的方块将开始下落
  local i t1 t2 t3

  #显示边框
  echo -ne "\033[1m"
  echo -ne "\033[3${cBorder}m\033[4${cBorder}m"

  ((t2 = iLeft + 1))
  ((t3 = iLeft + iTrayWidth * 2 + 3))
  for ((i = 0; i < iTrayHeight; i++)); do
    ((t1 = i + iTop + 2))
    echo -ne "\033[${t1};${t2}H||"
    echo -ne "\033[${t1};${t3}H||"
  done

  ((t2 = iTop + iTrayHeight + 2))
  for ((i = 0; i < iTrayWidth + 2; i++)); do
    ((t1 = i * 2 + iLeft + 1))
    echo -ne "\033[${iTrayTop};${t1}H=="
    echo -ne "\033[${t2};${t1}H=="
  done
  echo -ne "\033[0m"

  #显示"Score"和"Level"字样
  echo -ne "\033[1m"
  ((t1 = iLeft + iTrayWidth * 2 + 7))
  ((t2 = iTop + 10))
  echo -ne "\033[3${cScore}m\033[${t2};${t1}HScore"
  ((t2 = iTop + 11))
  echo -ne "\033[3${cScoreValue}m\033[${t2};${t1}H${iScore}"
  ((t2 = iTop + 13))
  echo -ne "\033[3${cScore}m\033[${t2};${t1}HLevel"
  ((t2 = iTop + 14))
  echo -ne "\033[3${cScoreValue}m\033[${t2};${t1}H${iLevel}"
  echo -ne "\033[0m"
}

#退出时显示GameOVer!
function ShowExit() {
  local y
  ((y = iTrayHeight + iTrayTop + 3))
  echo -e "\033[${y};0HGameOver!\033[0m"
  exit
}

#显示用法.
function Usage() {
  cat <<EOF
Usage: $APP_NAME
Start tetris game.

  -h, --help              display this help and exit
      --version           output version information and exit
EOF
}

#游戏主程序在这儿开始.
if [[ "$1" == "-h" || "$1" == "--help" ]]; then
  Usage
elif [[ "$1" == "--version" ]]; then
  echo "$APP_NAME $APP_VERSION"
elif [[ "$1" == "--show" ]]; then
  #当发现具有参数--show时，运行显示函数
  RunAsDisplayer
else
  bash $0 --show &#以参数--show将本程序再运行一遍
  RunAsKeyReceiver $! #以上一行产生的进程的进程号作为参数
fi