app.py

import streamlit as st

# Initialize the board and game state
if "board" not in st.session_state:
    st.session_state.board = [""] * 9
    st.session_state.current_player = "X"
    st.session_state.winner = None

def check_winner(board):
    win_conditions = [
        [0,1,2], [3,4,5], [6,7,8],  # rows
        [0,3,6], [1,4,7], [2,5,8],  # cols
        [0,4,8], [2,4,6]            # diagonals
    ]
    for condition in win_conditions:
        a, b, c = condition
        if board[a] and board[a] == board[b] == board[c]:
            return board[a]
    if all(cell != "" for cell in board):
        return "Draw"
    return None

def restart_game():
    st.session_state.board = [""] * 9
    st.session_state.current_player = "X"
    st.session_state.winner = None

st.title("🎮 Tic Tac Toe Game")
st.markdown("Play against a friend in the browser!")

# Game board layout
cols = st.columns(3)
for i in range(3):
    for j in range(3):
        idx = i * 3 + j
        with cols[j]:
            if st.button(st.session_state.board[idx] or " ", key=idx, use_container_width=True):
                if not st.session_state.board[idx] and not st.session_state.winner:
                    st.session_state.board[idx] = st.session_state.current_player
                    st.session_state.winner = check_winner(st.session_state.board)
                    if not st.session_state.winner:
                        st.session_state.current_player = "O" if st.session_state.current_player == "X" else "X"

# Display result
if st.session_state.winner:
    if st.session_state.winner == "Draw":
        st.success("It's a draw!")
    else:
        st.success(f"Player {st.session_state.winner} wins!")

st.button("🔁 Restart Game", on_click=restart_game)