#!/bin/ksh

set -A g

g[1]=" "
g[2]=" "
g[3]=" "
g[4]=" "
g[5]=" "
g[6]=" "
g[7]=" "
g[8]=" "
g[9]=" "

turn=0

function print_game
{
  clear
  echo "1..3 - first row, 4..6 - second row, 7..9 - third row, q - quit"
  echo "+---+---+---+"
  echo "| ${g[1]} | ${g[2]} | ${g[3]} |"
  echo "+---+---+---+"
  echo "| ${g[4]} | ${g[5]} | ${g[6]} |"
  echo "+---+---+---+"
  echo "| ${g[7]} | ${g[8]} | ${g[9]} |"
  echo "+---+---+---+"
}

function won
{
  if [ "${g[1]}" == "$1" ] && [ "${g[2]}" == "$1" ] && [ "${g[3]}" == "$1" ]; then
    return 1
  fi
  if [ "${g[4]}" == "$1" ] && [ "${g[5]}" == "$1" ] && [ "${g[6]}" == "$1" ]; then
    return 1
  fi
  if [ "${g[7]}" == "$1" ] && [ "${g[8]}" == "$1" ] && [ "${g[9]}" == "$1" ]; then
    return 1
  fi

  if [ "${g[1]}" == "$1" ] && [ "${g[4]}" == "$1" ] && [ "${g[7]}" == "$1" ]; then
    return 1
  fi
  if [ "${g[2]}" == "$1" ] && [ "${g[5]}" == "$1" ] && [ "${g[8]}" == "$1" ]; then
    return 1
  fi
  if [ "${g[3]}" == "$1" ] && [ "${g[6]}" == "$1" ] && [ "${g[9]}" == "$1" ]; then
    return 1
  fi

  if [ "${g[1]}" == "$1" ] && [ "${g[5]}" == "$1" ] && [ "${g[9]}" == "$1" ]; then
    return 1
  fi
  if [ "${g[3]}" == "$1" ] && [ "${g[5]}" == "$1" ] && [ "${g[7]}" == "$1" ]; then
    return 1
  fi

  return 0
}

function computer_play
{
  found=0

  while [ $found -eq 0 ]; do
    num=$((RANDOM%9+1))
    if [ "${g[$num]}" == " " ]; then
      g[$num]="o"
      found=1
    fi
  done
}

function is_game_dead
{
  for i in "${g[@]}"; do
    if [ "$i" == " " ]; then
      return 0
    fi
  done

  return 1
}

print_game

while read -rn1 key; do
  case "$key" in
    [1-9])
      if [ "${g[$key]}" != " " ]; then
        echo "Already taken!"
        sleep 1
      else
        g[$key]="x"
        turn=1
        print_game
      fi
      ;;
    "q")
      exit 0
      ;;
    *)
      echo "Wrong key!"
      sleep 1
      clear
      print_game
    ;;
  esac

  won "x"
  if [ $? -ne 0 ]; then
    echo "YOU WON! :)"
    exit 0
  fi

  if [ $turn -eq 1 ]; then
    is_game_dead
    if [ $? -eq 1 ]; then
      echo "No one won - play again"
      exit 0
    fi
    sleep 1
    computer_play
    print_game
    turn=0
  fi

  won "o"
  if [ $? -ne 0 ]; then
    echo "YOU LOST! :X"
    exit 0
  fi

done