git.cworth.org Git - lmno.games/blob - tictactoe/tictactoe.jsx

   1 const Team = {
   2   X: 0,
   3   O: 1,
   4   properties: {
   5     0: {name: "X"},
   6     1: {name: "O"}
   7   }
   8 };
   9
  10 function undisplay(element) {
  11   element.style.display="none";
  12 }
  13
  14 function add_message(severity, message) {
  15   message = `<div class="message ${severity}" onclick="undisplay(this)">
  16 <span class="hide-button" onclick="undisplay(this.parentElement)">&times;</span>
  17 ${message}
  18 </div>`;
  19   const message_area = document.getElementById('message-area');
  20   message_area.insertAdjacentHTML('beforeend', message);
  21 }
  22
  23 /*********************************************************
  24  * Handling server-sent event stream                     *
  25  *********************************************************/
  26
  27 const events = new EventSource("events");
  28
  29 events.onerror = function(event) {
  30   if (event.target.readyState === EventSource.CLOSED) {
  31       add_message("danger", "Connection to server lost.");
  32   }
  33 };
  34
  35 events.addEventListener("game-info", event => {
  36   const info = JSON.parse(event.data);
  37
  38   window.game.set_game_info(info);
  39 });
  40
  41 events.addEventListener("player-info", event => {
  42   const info = JSON.parse(event.data);
  43
  44   window.game.set_player_info(info);
  45 });
  46
  47 events.addEventListener("player-update", event => {
  48   const info = JSON.parse(event.data);
  49
  50   if (info.id === window.game.state.player_info.id)
  51     window.game.set_player_info(info);
  52 });
  53
  54 events.addEventListener("move", event => {
  55   const move = JSON.parse(event.data);
  56
  57   window.game.receive_move(move);
  58 });
  59
  60 events.addEventListener("game-state", event => {
  61   const state = JSON.parse(event.data);
  62
  63   window.game.reset_board();
  64
  65   for (let square of state.moves) {
  66     window.game.receive_move(square);
  67   }
  68 });
  69
  70 /*********************************************************
  71  * Game and supporting classes                           *
  72  *********************************************************/
  73
  74 function GameInfo(props) {
  75   return (
  76     <div className="game-info">
  77       <h2>{props.id}</h2>
  78       Invite a friend to play by sending this URL: {props.url}
  79     </div>
  80   );
  81 }
  82
  83 function PlayerInfo(props) {
  84   return (
  85     <div className="player-info">
  86       <h2>Player</h2>
  87       {props.name}, ID: {props.id}, on team: {props.team}
  88     </div>
  89   );
  90 }
  91
  92 function Square(props) {
  93   let className = "square";
  94
  95   if (props.value) {
  96     className += " occupied";
  97   } else if (props.active) {
  98     className += " open";
  99   }
 100
 101   const onClick = props.active ? props.onClick : null;
 102
 103   return (
 104     <div className={className}
 105          onClick={onClick}>
 106       {props.value}
 107     </div>
 108   );
 109 }
 110
 111 class Board extends React.Component {
 112   render_square(i) {
 113     const value = this.props.squares[i];
 114     return (
 115       <Square
 116         value={value}
 117         active={! this.props.game_over && ! value}
 118         onClick={() => this.props.onClick(i)}
 119       />
 120     );
 121   }
 122
 123   render() {
 124     return (
 125       <div>
 126         <div className="board-row">
 127           {this.render_square(0)}
 128           {this.render_square(1)}
 129           {this.render_square(2)}
 130         </div>
 131         <div className="board-row">
 132           {this.render_square(3)}
 133           {this.render_square(4)}
 134           {this.render_square(5)}
 135         </div>
 136         <div className="board-row">
 137           {this.render_square(6)}
 138           {this.render_square(7)}
 139           {this.render_square(8)}
 140         </div>
 141       </div>
 142     );
 143   }
 144 }
 145
 146 function fetch_post_json(api = '', data = {}) {
 147   const response = fetch(api, {
 148     method: 'POST',
 149     headers: {
 150       'Content-Type': 'application/json'
 151     },
 152     body: JSON.stringify(data)
 153   });
 154   return response;
 155 }
 156
 157 class Game extends React.Component {
 158   constructor(props) {
 159     super(props);
 160     this.state = {
 161       game_info: {},
 162       player_info: {},
 163       history: [
 164         {
 165           squares: Array(9).fill(null)
 166         }
 167       ],
 168       step_number: 0,
 169       next_to_play: Team.X
 170     };
 171   }
 172
 173   set_game_info(info) {
 174     this.setState({
 175       game_info: info
 176     });
 177   }
 178
 179   set_player_info(info) {
 180     this.setState({
 181       player_info: info
 182     });
 183   }
 184
 185   send_move(i) {
 186     return fetch_post_json("move", { move: i });
 187   }
 188
 189   reset_board() {
 190     this.setState({
 191       history: [
 192         {
 193           squares: Array(9).fill(null)
 194         }
 195       ],
 196       step_number: 0,
 197       next_to_play: Team.X
 198     });
 199   }
 200
 201   receive_move(i) {
 202     const history = this.state.history.slice(0, this.state.step_number + 1);
 203     const current = history[history.length - 1];
 204     const squares = current.squares.slice();
 205     if (calculate_winner(squares) || squares[i]) {
 206       return;
 207     }
 208     squares[i] = Team.properties[this.state.next_to_play].name;
 209     let next_to_play;
 210     if (this.state.next_to_play === Team.X)
 211       next_to_play = Team.O;
 212     else
 213       next_to_play = Team.X;
 214     this.setState({
 215       history: history.concat([
 216         {
 217           squares: squares
 218         }
 219       ]),
 220       step_number: history.length,
 221       next_to_play: next_to_play
 222     });
 223   }
 224
 225   async handle_click(i) {
 226     const response = await this.send_move(i);
 227     if (response.status == 200) {
 228       const result = await response.json();
 229       if (! result.legal)
 230         add_message("danger", result.message);
 231     } else {
 232       add_message("danger", `Error occurred sending move`);
 233     }
 234   }
 235
 236   render() {
 237     const history = this.state.history;
 238     const current = history[this.state.step_number];
 239     const winner = calculate_winner(current.squares);
 240
 241     let status;
 242     if (winner) {
 243       status = "Winner: " + winner;
 244     } else {
 245       status = "Next player: " + (Team.properties[this.state.next_to_play].name);
 246     }
 247
 248     return [
 249       <GameInfo
 250         id={this.state.game_info.id}
 251         url={this.state.game_info.url}
 252       />,
 253       <PlayerInfo
 254         id={this.state.player_info.id}
 255         name={this.state.player_info.name}
 256         team={this.state.player_info.team}
 257       />,
 258       <div className="game">
 259         <div>{status}</div>
 260         <div className="game-board">
 261           <Board
 262             game_over={winner}
 263             squares={current.squares}
 264             onClick={i => this.handle_click(i)}
 265           />
 266         </div>
 267       </div>
 268     ];
 269   }
 270 }
 271
 272 ReactDOM.render(<Game
 273                   ref={(me) => window.game = me}
 274                 />, document.getElementById("tictactoe"));
 275
 276 function calculate_winner(squares) {
 277   const lines = [
 278     [0, 1, 2],
 279     [3, 4, 5],
 280     [6, 7, 8],
 281     [0, 3, 6],
 282     [1, 4, 7],
 283     [2, 5, 8],
 284     [0, 4, 8],
 285     [2, 4, 6]
 286   ];
 287   for (let i = 0; i < lines.length; i++) {
 288     const [a, b, c] = lines[i];
 289     if (squares[a] && squares[a] === squares[b] && squares[a] === squares[c]) {
 290       return squares[a];
 291     }
 292   }
 293   return null;
 294 }