tic_tac_toe.exs

defmodule TicTacToe do
  def play do
    move(" ", " ", " ", " ", " ", " ", " ", " ", " ", "X")
  end

  def draw_grid(a1, b1, c1, a2, b2, c2, a3, b3, c3) do
    IO.puts "\n   a   b   c "
    IO.puts "1  #{a1} | #{b1} | #{c1} "
    IO.puts "  ---+---+---"
    IO.puts "2  #{a2} | #{b2} | #{c2} "
    IO.puts "  ---+---+---"
    IO.puts "3  #{a3} | #{b3} | #{c3} "
  end

  def move(a1, b1, c1, a2, b2, c2, a3, b3, c3, player) do
    draw_grid(a1, b1, c1, a2, b2, c2, a3, b3, c3)
    move = String.trim(IO.gets("\n#{player} move?  "))
    make_move(move, a1, b1, c1, a2, b2, c2, a3, b3, c3, player)
  end

  def make_move("a1", " ", b1, c1, a2, b2, c2, a3, b3, c3, player) do
    winner(player, b1, c1, a2, b2, c2, a3, b3, c3, next_player(player))
  end
  def make_move("b1", a1, " ", c1, a2, b2, c2, a3, b3, c3, player) do
    winner(a1, player, c1, a2, b2, c2, a3, b3, c3, next_player(player))
  end
  def make_move("c1", a1, b1, " ", a2, b2, c2, a3, b3, c3, player) do
    winner(a1, b1, player, a2, b2, c2, a3, b3, c3, next_player(player))
  end
  def make_move("a2", a1, b1, c1, " ", b2, c2, a3, b3, c3, player) do
    winner(a1, b1, c1, player, b2, c2, a3, b3, c3, next_player(player))
  end
  def make_move("b2", a1, b1, c1, a2, " ", c2, a3, b3, c3, player) do
    winner(a1, b1, c1, a2, player, c2, a3, b3, c3, next_player(player))
  end
  def make_move("c2", a1, b1, c1, a2, b2, " ", a3, b3, c3, player) do
    winner(a1, b1, c1, a2, b2, player, a3, b3, c3, next_player(player))
  end
  def make_move("a3", a1, b1, c1, a2, b2, c2, " ", b3, c3, player) do
    winner(a1, b1, c1, a2, b2, c2, player, b3, c3, next_player(player))
  end
  def make_move("b3", a1, b1, c1, a2, b2, c2, a3, " ", c3, player) do
    winner(a1, b1, c1, a2, b2, c2, a3, player, c3, next_player(player))
  end
  def make_move("c3", a1, b1, c1, a2, b2, c2, a3, b3, " ", player) do
    winner(a1, b1, c1, a2, b2, c2, a3, b3, player, next_player(player))
  end
  def make_move(_move, a1, b1, c1, a2, b2, c2, a3, b3, c3, player) do
    IO.puts "Invalid move."
    move(a1, b1, c1, a2, b2, c2, a3, b3, c3, player)
  end

  def declare_winner(player) do
    IO.puts("#{player} is the winner!")
  end

  def winner("X", "X", "X",_a2, _b2, _c2, _a3, _b3, _c3, _player) do
    declare_winner("X") 
  end
  def winner(_a1, _b1,_c1, "X", "X", "X", _a3, _b3, _c3, _player) do
    declare_winner("X")
  end
  def winner(_a1, _b1, _c1, _a2, _b2, _c2, "X", "X", "X", _player) do
    declare_winner("X")
  end
  def winner("X", _b1, _c1, "X", _b2, _c2, "X", _b3, _c3, _player) do
    declare_winner("X")
  end
  def winner(_a1, "X",_c1, _a2, "X", _c2, _a3, "X", _c3, _player) do
    declare_winner("X")
  end

  def winner(_a1, _b1, "X", _a2, _b2, "X", _a3, _b3, "X", _player) do
    declare_winner("X")
  end

  def winner("X", _b1, _c1, _a2, "X", _c2, _a3, _b3, "X", _player) do
    declare_winner("X")
  end
  def winner(_a1, _b1, "X", _a2, "X", _c2, "X", _b3, _c3, _player) do
    declare_winner("X")
  end

  def winner("O", "O", "O",_a2, _b2, _c2, _a3, _b3, _c3, _player) do
    declare_winner("O") 
  end
  def winner(_a1, _b1,_c1, "O", "O", "O", _a3, _b3, _c3, _player) do
    declare_winner("O")
  end
  def winner(_a1, _b1, _c1, _a2, _b2, _c2, "O", "O", "O", _player) do
    declare_winner("O")
  end
  def winner("O", _b1, _c1, "O", _b2, _c2, "O", _b3, _c3, _player) do
    declare_winner("O")
  end
  def winner(_a1, "O", _c1, _a2, "O", _c2, _a3, "O", _c3, _player) do
    declare_winner("O")
  end

  def winner(_a1, _b1, "O", _a2, _b2, "O", _a3, _b3, "O", _player) do
    declare_winner("O")
  end

  def winner("O", _b1, _c1, _a2, "O", _c2, _a3, _b3, "O", _player) do
    declare_winner(O)
  end
  def winner(_a1, _b1, "O", _a2, "O", _c2, "O", _b3, _c3, _player) do
    declare_winner(O)
  end
  def winner(a1, b1, c1, a2, b2, c2, a3, b3, c3, player) do
    move(a1, b1, c1, a2, b2, c2, a3, b3, c3, player)
  end



  def next_player("X"), do: "O"
  def next_player("O"), do: "X"
end

TicTacToe.play