#!/usr/bin/env python
# coding: utf-8

# # Milestone Project 1: Full Walk-through Code Solution
# 
# Below is the filled in code that goes along with the complete walk-through video. Check out the corresponding lecture videos for more information on this code!

# In[3]:


# For using the same code in either Python 2 or 3
from __future__ import print_function 

## Note: Python 2 users, use raw_input() to get player input. Python 3 users, use input()


# **Step 1: Write a function that can print out a board. Set up your board as a list, where each index 1-9 corresponds with a number on a number pad, so you get a 3 by 3 board representation.**

# In[4]:


from IPython.display import clear_output
def display_board(board):
    
    clear_output()
    print('   |   |')
    print(' ' + board[7] + ' | ' + board[8] + ' | ' + board[9])
    print('   |   |')
    print('-----------')
    print('   |   |')
    print(' ' + board[4] + ' | ' + board[5] + ' | ' + board[6])
    print('   |   |')
    print('-----------')
    print('   |   |')
    print(' ' + board[1] + ' | ' + board[2] + ' | ' + board[3])
    print('   |   |')


# **Step 2: Write a function that can take in a player input and assign their marker as 'X' or 'O'. Think about using *while* loops to continually ask until you get a correct answer.**

# In[5]:


def player_input():
    
    marker = ''
    while not (marker == 'X' or marker == 'O'):
        marker = raw_input('Player 1: Do you want to be X or O?').upper()

    if marker == 'X':
        return ('X', 'O')
    else:
        return ('O', 'X')


# **Step 3: Write a function that takes, in the board list object, a marker ('X' or 'O'), and a desired position (number 1-9) and assigns it to the board.**

# In[6]:


def place_marker(board, marker, position):
    board[position] = marker


# **Step 4: Write a function that takes in a board and checks to see if someone has won. **

# In[7]:


def win_check(board,mark):
    
    return ((board[7] == mark and board[8] == mark and board[9] == mark) or # across the top
    (board[4] == mark and board[5] == mark and board[6] == mark) or # across the middle
    (board[1] == mark and board[2] == mark and board[3] == mark) or # across the bottom
    (board[7] == mark and board[4] == mark and board[1] == mark) or # down the middle
    (board[8] == mark and board[5] == mark and board[2] == mark) or # down the middle
    (board[9] == mark and board[6] == mark and board[3] == mark) or # down the right side
    (board[7] == mark and board[5] == mark and board[3] == mark) or # diagonal
    (board[9] == mark and board[5] == mark and board[1] == mark)) # diagonal


# **Step 5: Write a function that uses the random module to randomly decide which player goes first. You may want to lookup random.randint() Return a string of which player went first.**

# In[8]:


import random
def choose_first():
    if random.randint(0, 1) == 0:
        return 'Player 2'
    else:
        return 'Player 1'


# **Step 6: Write a function that returns a boolean indicating whether a space on the board is freely available.**

# In[9]:


def space_check(board, position):
    
    return board[position] == ' '


# **Step 7: Write a function that checks if the board is full and returns a boolean value. True if full, False otherwise.**

# In[10]:


def full_board_check(board):
    for i in range(1,10):
        if space_check(board, i):
            return False
    return True


# **Step 8: Write a function that asks for a player's next position (as a number 1-9) and then uses the function from step 6 to check if its a free position. If it is, then return the position for later use. **

# In[11]:


def player_choice(board):
    # Using strings because of raw_input
    position = ' '
    while position not in '1 2 3 4 5 6 7 8 9'.split() or not space_check(board, int(position)):
        
        position = raw_input('Choose your next position: (1-9) ')
    return int(position)


# **Step 9: Write a function that asks the player if they want to play again and returns a boolean True if they do want to play again.**

# In[12]:


def replay():
    
    return raw_input('Do you want to play again? Enter Yes or No: ').lower().startswith('y')


# **Step 10: Here comes the hard part! Use while loops and the functions you've made to run the game!**

# In[14]:


print('Welcome to Tic Tac Toe!')

while True:
    # Reset the board
    theBoard = [' '] * 10
    player1_marker, player2_marker = player_input()
    turn = choose_first()
    print(turn + ' will go first.')
    game_on = True

    while game_on:
        if turn == 'Player 1':
            # Player1's turn.
            
            display_board(theBoard)
            position = player_choice(theBoard)
            place_marker(theBoard, player1_marker, position)

            if win_check(theBoard, player1_marker):
                display_board(theBoard)
                print('Congratulations! You have won the game!')
                game_on = False
            else:
                if full_board_check(theBoard):
                    display_board(theBoard)
                    print('The game is a draw!')
                    break
                else:
                    turn = 'Player 2'

        else:
            # Player2's turn.
            
            display_board(theBoard)
            position = player_choice(theBoard)
            place_marker(theBoard, player2_marker, position)

            if win_check(theBoard, player2_marker):
                display_board(theBoard)
                print('Player 2 has won!')
                game_on = False
            else:
                if full_board_check(theBoard):
                    display_board(theBoard)
                    print('The game is a tie!')
                    break
                else:
                    turn = 'Player 1'

    if not replay():
        break


# ## Good Job!