const Team = {
X: 0,
O: 1,
properties: {
0: {name: "X"},
1: {name: "O"}
}
};
function undisplay(element) {
element.style.display="none";
}
function add_message(severity, message) {
message = `
×
${message}
`;
const message_area = document.getElementById('message-area');
message_area.insertAdjacentHTML('beforeend', message);
}
/*********************************************************
* Handling server-sent event stream *
*********************************************************/
const events = new EventSource("events");
events.onerror = function(event) {
if (event.target.readyState === EventSource.CLOSED) {
add_message("danger", "Connection to server lost.");
}
};
events.addEventListener("game-info", event => {
const info = JSON.parse(event.data);
window.game.set_game_info(info);
});
events.addEventListener("player-info", event => {
const info = JSON.parse(event.data);
window.game.set_player_info(info);
});
events.addEventListener("player-update", event => {
const info = JSON.parse(event.data);
if (info.id === window.game.state.player_info.id)
window.game.set_player_info(info);
});
events.addEventListener("move", event => {
const move = JSON.parse(event.data);
window.game.receive_move(move);
});
events.addEventListener("game-state", event => {
const state = JSON.parse(event.data);
window.game.reset_board();
for (let square of state.moves) {
window.game.receive_move(square);
}
});
/*********************************************************
* Game and supporting classes *
*********************************************************/
function GameInfo(props) {
if (! props.id)
return null;
return (
{props.id}
Invite a friend to play by sending this URL: {props.url}
);
}
function PlayerInfo(props) {
if (! props.id)
return null;
return (
Player
{props.name}, ID: {props.id},
{props.team ? ` on team ${props.team}` : " not on a team"}
);
}
function Square(props) {
let className = "square";
if (props.value) {
className += " occupied";
} else if (props.active) {
className += " open";
}
const onClick = props.active ? props.onClick : null;
return (
{props.value}
);
}
class Board extends React.Component {
render_square(i) {
const value = this.props.squares[i];
return (
this.props.onClick(i)}
/>
);
}
render() {
return (
{this.render_square(0)}
{this.render_square(1)}
{this.render_square(2)}
{this.render_square(3)}
{this.render_square(4)}
{this.render_square(5)}
{this.render_square(6)}
{this.render_square(7)}
{this.render_square(8)}
);
}
}
function fetch_method_json(method, api = '', data = {}) {
const response = fetch(api, {
method: method,
headers: {
'Content-Type': 'application/json'
},
body: JSON.stringify(data)
});
return response;
}
function fetch_post_json(api = '', data = {}) {
return fetch_method_json('POST', api, data);
}
async function fetch_put_json(api = '', data = {}) {
return fetch_method_json('PUT', api, data);
}
class Game extends React.Component {
constructor(props) {
super(props);
this.state = {
game_info: {},
player_info: {},
history: [
{
squares: Array(9).fill(null)
}
],
step_number: 0,
next_to_play: Team.X
};
}
set_game_info(info) {
this.setState({
game_info: info
});
}
set_player_info(info) {
this.setState({
player_info: info
});
}
send_move(i) {
return fetch_post_json("move", { move: i });
}
reset_board() {
this.setState({
history: [
{
squares: Array(9).fill(null)
}
],
step_number: 0,
next_to_play: Team.X
});
}
receive_move(i) {
const history = this.state.history.slice(0, this.state.step_number + 1);
const current = history[history.length - 1];
const squares = current.squares.slice();
if (calculate_winner(squares) || squares[i]) {
return;
}
squares[i] = Team.properties[this.state.next_to_play].name;
let next_to_play;
if (this.state.next_to_play === Team.X)
next_to_play = Team.O;
else
next_to_play = Team.X;
this.setState({
history: history.concat([
{
squares: squares
}
]),
step_number: history.length,
next_to_play: next_to_play
});
}
async handle_click(i) {
const response = await this.send_move(i);
if (response.status == 200) {
const result = await response.json();
if (! result.legal)
add_message("danger", result.message);
} else {
add_message("danger", `Error occurred sending move`);
}
}
join_team(team) {
fetch_put_json("player", {team: team});
}
render() {
const state = this.state;
const history = state.history;
const current = history[state.step_number];
const winner = calculate_winner(current.squares);
var board_active;
let status;
if (winner) {
status = "Winner: " + winner;
board_active = false;
} else {
if (state.player_info.team === Team.properties[state.next_to_play].name) {
status = "Your turn. Make a move.";
board_active = true;
} else {
status = "Waiting for your opponent to move.";
board_active = false;
}
}
return [
,
,
{status}
this.handle_click(i)}
/>
];
}
}
ReactDOM.render( window.game = me}
/>, document.getElementById("tictactoe"));
function calculate_winner(squares) {
const lines = [
[0, 1, 2],
[3, 4, 5],
[6, 7, 8],
[0, 3, 6],
[1, 4, 7],
[2, 5, 8],
[0, 4, 8],
[2, 4, 6]
];
for (let i = 0; i < lines.length; i++) {
const [a, b, c] = lines[i];
if (squares[a] && squares[a] === squares[b] && squares[a] === squares[c]) {
return squares[a];
}
}
return null;
}