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   if (! props.id)
  76     return null;
  77
  78   return (
  79     <div className="game-info">
  80       <h2>{props.id}</h2>
  81       Invite a friend to play by sending this URL: {props.url}
  82     </div>
  83   );
  84 }
  85
  86 function PlayerInfo(props) {
  87   if (! props.id)
  88     return null;
  89
  90   return (
  91     <div className="player-info">
  92       <h2>Player</h2>
  93       {props.name}, ID: {props.id},
  94       {props.team ? ` on team ${props.team}` : " not on a team"}
  95     </div>
  96   );
  97 }
  98
  99 function Square(props) {
 100   let className = "square";
 101
 102   if (props.value) {
 103     className += " occupied";
 104   } else if (props.active) {
 105     className += " open";
 106   }
 107
 108   const onClick = props.active ? props.onClick : null;
 109
 110   return (
 111     <div className={className}
 112          onClick={onClick}>
 113       {props.value}
 114     </div>
 115   );
 116 }
 117
 118 class Board extends React.Component {
 119   render_square(i) {
 120     const value = this.props.squares[i];
 121     return (
 122       <Square
 123         value={value}
 124         active={! this.props.game_over && ! value}
 125         onClick={() => this.props.onClick(i)}
 126       />
 127     );
 128   }
 129
 130   render() {
 131     return (
 132       <div>
 133         <div className="board-row">
 134           {this.render_square(0)}
 135           {this.render_square(1)}
 136           {this.render_square(2)}
 137         </div>
 138         <div className="board-row">
 139           {this.render_square(3)}
 140           {this.render_square(4)}
 141           {this.render_square(5)}
 142         </div>
 143         <div className="board-row">
 144           {this.render_square(6)}
 145           {this.render_square(7)}
 146           {this.render_square(8)}
 147         </div>
 148       </div>
 149     );
 150   }
 151 }
 152
 153 function fetch_method_json(method, api = '', data = {}) {
 154   const response = fetch(api, {
 155     method: method,
 156     headers: {
 157       'Content-Type': 'application/json'
 158     },
 159     body: JSON.stringify(data)
 160   });
 161   return response;
 162 }
 163
 164 function fetch_post_json(api = '', data = {}) {
 165   return fetch_method_json('POST', api, data);
 166 }
 167
 168 async function fetch_put_json(api = '', data = {}) {
 169   return fetch_method_json('PUT', api, data);
 170 }
 171
 172 class Game extends React.Component {
 173   constructor(props) {
 174     super(props);
 175     this.state = {
 176       game_info: {},
 177       player_info: {},
 178       history: [
 179         {
 180           squares: Array(9).fill(null)
 181         }
 182       ],
 183       step_number: 0,
 184       next_to_play: Team.X
 185     };
 186   }
 187
 188   set_game_info(info) {
 189     this.setState({
 190       game_info: info
 191     });
 192   }
 193
 194   set_player_info(info) {
 195     this.setState({
 196       player_info: info
 197     });
 198   }
 199
 200   send_move(i) {
 201     return fetch_post_json("move", { move: i });
 202   }
 203
 204   reset_board() {
 205     this.setState({
 206       history: [
 207         {
 208           squares: Array(9).fill(null)
 209         }
 210       ],
 211       step_number: 0,
 212       next_to_play: Team.X
 213     });
 214   }
 215
 216   receive_move(i) {
 217     const history = this.state.history.slice(0, this.state.step_number + 1);
 218     const current = history[history.length - 1];
 219     const squares = current.squares.slice();
 220     if (calculate_winner(squares) || squares[i]) {
 221       return;
 222     }
 223     squares[i] = Team.properties[this.state.next_to_play].name;
 224     let next_to_play;
 225     if (this.state.next_to_play === Team.X)
 226       next_to_play = Team.O;
 227     else
 228       next_to_play = Team.X;
 229     this.setState({
 230       history: history.concat([
 231         {
 232           squares: squares
 233         }
 234       ]),
 235       step_number: history.length,
 236       next_to_play: next_to_play
 237     });
 238   }
 239
 240   async handle_click(i) {
 241     const response = await this.send_move(i);
 242     if (response.status == 200) {
 243       const result = await response.json();
 244       if (! result.legal)
 245         add_message("danger", result.message);
 246     } else {
 247       add_message("danger", `Error occurred sending move`);
 248     }
 249   }
 250
 251   join_team(team) {
 252     fetch_put_json("player", {team: team});
 253   }
 254
 255   render() {
 256     const history = this.state.history;
 257     const current = history[this.state.step_number];
 258     const winner = calculate_winner(current.squares);
 259
 260     let status;
 261     if (winner) {
 262       status = "Winner: " + winner;
 263     } else {
 264       status = "Next player: " + (Team.properties[this.state.next_to_play].name);
 265     }
 266
 267     return [
 268       <GameInfo
 269         key="game-info"
 270         id={this.state.game_info.id}
 271         url={this.state.game_info.url}
 272       />,
 273       <PlayerInfo
 274         key="player-info"
 275         id={this.state.player_info.id}
 276         name={this.state.player_info.name}
 277         team={this.state.player_info.team}
 278       />,
 279       <div key="game" className="game">
 280         <button className="inline"
 281                 onClick={() => this.join_team('X')}>Join Team X</button>
 282         &nbsp;
 283         <button className="inline"
 284                 onClick={() => this.join_team('O')}>Join Team O</button>
 285         <div>{status}</div>
 286         <div className="game-board">
 287           <Board
 288             game_over={winner}
 289             squares={current.squares}
 290             onClick={i => this.handle_click(i)}
 291           />
 292         </div>
 293       </div>
 294     ];
 295   }
 296 }
 297
 298 ReactDOM.render(<Game
 299                   ref={(me) => window.game = me}
 300                 />, document.getElementById("tictactoe"));
 301
 302 function calculate_winner(squares) {
 303   const lines = [
 304     [0, 1, 2],
 305     [3, 4, 5],
 306     [6, 7, 8],
 307     [0, 3, 6],
 308     [1, 4, 7],
 309     [2, 5, 8],
 310     [0, 4, 8],
 311     [2, 4, 6]
 312   ];
 313   for (let i = 0; i < lines.length; i++) {
 314     const [a, b, c] = lines[i];
 315     if (squares[a] && squares[a] === squares[b] && squares[a] === squares[c]) {
 316       return squares[a];
 317     }
 318   }
 319   return null;
 320 }