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-enter", event => {
  48   const info = JSON.parse(event.data);
  49
  50   window.game.set_opponent_info(info);
  51 });
  52
  53 events.addEventListener("player-update", event => {
  54   const info = JSON.parse(event.data);
  55
  56   if (info.id === window.game.state.player_info.id)
  57     window.game.set_player_info(info);
  58   else
  59     window.game.set_opponent_info(info);
  60 });
  61
  62 events.addEventListener("move", event => {
  63   const move = JSON.parse(event.data);
  64
  65   window.game.receive_move(move);
  66 });
  67
  68 events.addEventListener("game-state", event => {
  69   const state = JSON.parse(event.data);
  70
  71   window.game.reset_board();
  72
  73   for (let square of state.moves) {
  74     window.game.receive_move(square);
  75   }
  76 });
  77
  78 /*********************************************************
  79  * Game and supporting classes                           *
  80  *********************************************************/
  81
  82 function GameInfo(props) {
  83   if (! props.id)
  84     return null;
  85
  86   return (
  87     <div className="game-info">
  88       <h2>{props.id}</h2>
  89       Invite a friend to play by sending this URL: {props.url}
  90     </div>
  91   );
  92 }
  93
  94 function PlayerInfo(props) {
  95   if (! props.player.id)
  96     return null;
  97
  98   return (
  99     <div className="player-info">
 100       <h2>Players</h2>
 101       {props.player.name}
 102       {props.player.team ? ` (${props.player.team})` : ""}
 103       {", "}
 104       {props.opponent.name}
 105       {props.opponent.team ? ` (${props.opponent.team})` : ""}
 106     </div>
 107   );
 108 }
 109
 110 function Square(props) {
 111   let className = "square";
 112
 113   if (props.value) {
 114     className += " occupied";
 115   } else if (props.active) {
 116     className += " open";
 117   }
 118
 119   const onClick = props.active ? props.onClick : null;
 120
 121   return (
 122     <div className={className}
 123          onClick={onClick}>
 124       {props.value}
 125     </div>
 126   );
 127 }
 128
 129 class Board extends React.Component {
 130   render_square(i) {
 131     const value = this.props.squares[i];
 132     return (
 133       <Square
 134         value={value}
 135         active={this.props.active && ! value}
 136         onClick={() => this.props.onClick(i)}
 137       />
 138     );
 139   }
 140
 141   render() {
 142     return (
 143       <div>
 144         <div className="board-row">
 145           {this.render_square(0)}
 146           {this.render_square(1)}
 147           {this.render_square(2)}
 148         </div>
 149         <div className="board-row">
 150           {this.render_square(3)}
 151           {this.render_square(4)}
 152           {this.render_square(5)}
 153         </div>
 154         <div className="board-row">
 155           {this.render_square(6)}
 156           {this.render_square(7)}
 157           {this.render_square(8)}
 158         </div>
 159       </div>
 160     );
 161   }
 162 }
 163
 164 function fetch_method_json(method, api = '', data = {}) {
 165   const response = fetch(api, {
 166     method: method,
 167     headers: {
 168       'Content-Type': 'application/json'
 169     },
 170     body: JSON.stringify(data)
 171   });
 172   return response;
 173 }
 174
 175 function fetch_post_json(api = '', data = {}) {
 176   return fetch_method_json('POST', api, data);
 177 }
 178
 179 async function fetch_put_json(api = '', data = {}) {
 180   return fetch_method_json('PUT', api, data);
 181 }
 182
 183 class Game extends React.Component {
 184   constructor(props) {
 185     super(props);
 186     this.state = {
 187       game_info: {},
 188       player_info: {},
 189       opponent_info: {},
 190       history: [
 191         {
 192           squares: Array(9).fill(null)
 193         }
 194       ],
 195       step_number: 0,
 196       next_to_play: Team.X
 197     };
 198   }
 199
 200   set_game_info(info) {
 201     this.setState({
 202       game_info: info
 203     });
 204   }
 205
 206   set_player_info(info) {
 207     this.setState({
 208       player_info: info
 209     });
 210   }
 211
 212   set_opponent_info(info) {
 213     this.setState({
 214       opponent_info: info
 215     });
 216   }
 217
 218   reset_board() {
 219     this.setState({
 220       history: [
 221         {
 222           squares: Array(9).fill(null)
 223         }
 224       ],
 225       step_number: 0,
 226       next_to_play: Team.X
 227     });
 228   }
 229
 230   receive_move(i) {
 231     const history = this.state.history.slice(0, this.state.step_number + 1);
 232     const current = history[history.length - 1];
 233     const squares = current.squares.slice();
 234     if (calculate_winner(squares) || squares[i]) {
 235       return;
 236     }
 237     squares[i] = Team.properties[this.state.next_to_play].name;
 238     let next_to_play;
 239     if (this.state.next_to_play === Team.X)
 240       next_to_play = Team.O;
 241     else
 242       next_to_play = Team.X;
 243     this.setState({
 244       history: history.concat([
 245         {
 246           squares: squares
 247         }
 248       ]),
 249       step_number: history.length,
 250       next_to_play: next_to_play
 251     });
 252   }
 253
 254   async handle_click(i, first_move) {
 255     let move = { move: i };
 256     if (first_move) {
 257       move.assert_first_move = true;
 258     }
 259     const response = await fetch_post_json("move", move);
 260     if (response.status == 200) {
 261       const result = await response.json();
 262       if (! result.legal)
 263         add_message("danger", result.message);
 264     } else {
 265       add_message("danger", `Error occurred sending move`);
 266     }
 267   }
 268
 269   join_team(team) {
 270     fetch_put_json("player", {team: team});
 271   }
 272
 273   render() {
 274     const state = this.state;
 275     const history = state.history;
 276     const current = history[state.step_number];
 277     const winner = calculate_winner(current.squares);
 278     const first_move = state.step_number === 0;
 279     const my_team = state.player_info.team;
 280     var board_active;
 281
 282     let status;
 283     if (winner)
 284     {
 285       status = winner + " wins!";
 286       if (state.player_info.team != "")
 287       {
 288         if (my_team === winner)
 289           status += " Congratulations!";
 290         else
 291           status += " Better luck next time.";
 292       }
 293       board_active = false;
 294     }
 295     else if (first_move)
 296     {
 297       status = "Either player can make the first move.";
 298       board_active = true;
 299     }
 300     else if (my_team === "")
 301     {
 302       status = "You're just watching the game.";
 303       board_active = false;
 304     }
 305     else if (my_team === Team.properties[state.next_to_play].name)
 306     {
 307       status = "Your turn. Make a move.";
 308       board_active = true;
 309     }
 310     else
 311     {
 312       status = "Waiting for your opponent to move.";
 313       board_active = false;
 314     }
 315
 316     return [
 317       <GameInfo
 318         key="game-info"
 319         id={state.game_info.id}
 320         url={state.game_info.url}
 321       />,
 322       <PlayerInfo
 323         key="player-info"
 324         player={state.player_info}
 325         opponent={state.opponent_info}
 326       />,
 327       <div key="game" className="game">
 328         <button className="inline"
 329                 onClick={() => this.join_team('X')}>Join Team X</button>
 330         {" "}
 331         <button className="inline"
 332                 onClick={() => this.join_team('O')}>Join Team O</button>
 333         <div>{status}</div>
 334         <div className="game-board">
 335           <Board
 336             active={board_active}
 337             squares={current.squares}
 338             onClick={i => this.handle_click(i, first_move)}
 339           />
 340         </div>
 341       </div>
 342     ];
 343   }
 344 }
 345
 346 ReactDOM.render(<Game
 347                   ref={(me) => window.game = me}
 348                 />, document.getElementById("tictactoe"));
 349
 350 function calculate_winner(squares) {
 351   const lines = [
 352     [0, 1, 2],
 353     [3, 4, 5],
 354     [6, 7, 8],
 355     [0, 3, 6],
 356     [1, 4, 7],
 357     [2, 5, 8],
 358     [0, 4, 8],
 359     [2, 4, 6]
 360   ];
 361   for (let i = 0; i < lines.length; i++) {
 362     const [a, b, c] = lines[i];
 363     if (squares[a] && squares[a] === squares[b] && squares[a] === squares[c]) {
 364       return squares[a];
 365     }
 366   }
 367   return null;
 368 }