public/javascripts/components/game.js

   1 // Game logic on a variant page
   2 Vue.component('my-game', {
   3     data: function() {
   4         return {
   5             vr: null, //object to check moves, store them, FEN..
   6             mycolor: "w",
   7             possibleMoves: [], //filled after each valid click/dragstart
   8             choices: [], //promotion pieces, or checkered captures... (as moves)
   9             start: {}, //pixels coordinates + id of starting square (click or drag)
  10             selectedPiece: null, //moving piece (or clicked piece)
  11             conn: null, //socket connection
  12             score: "*", //'*' means 'unfinished'
  13             mode: "idle", //human, friend, computer or idle (when not playing)
  14             oppid: "", //opponent ID in case of HH game
  15             oppConnected: false,
  16             seek: false,
  17             fenStart: "",
  18             incheck: [],
  19             pgnTxt: "",
  20             expert: (getCookie("expert") === "1" ? true : false),
  21         };
  22     },
  23     render(h) {
  24         const [sizeX,sizeY] = VariantRules.size;
  25         const smallScreen = (screen.width <= 420);
  26         // Precompute hints squares to facilitate rendering
  27         let hintSquares = doubleArray(sizeX, sizeY, false);
  28         this.possibleMoves.forEach(m => { hintSquares[m.end.x][m.end.y] = true; });
  29         // Also precompute in-check squares
  30         let incheckSq = doubleArray(sizeX, sizeY, false);
  31         this.incheck.forEach(sq => { incheckSq[sq[0]][sq[1]] = true; });
  32         let elementArray = [];
  33         let actionArray = [];
  34         actionArray.push(
  35             h('button',
  36             {
  37                 on: { click: this.clickGameSeek },
  38                 attrs: { "aria-label": 'New online game' },
  39                 'class': {
  40                     "tooltip": true,
  41                     "bottom": true, //display below
  42                     "seek": this.seek,
  43                     "playing": this.mode == "human",
  44                     "small": smallScreen,
  45                 },
  46             },
  47             [h('i', { 'class': { "material-icons": true } }, "accessibility")])
  48         );
  49         if (["idle","computer"].includes(this.mode))
  50         {
  51             actionArray.push(
  52                 h('button',
  53                 {
  54                     on: { click: this.clickComputerGame },
  55                     attrs: { "aria-label": 'New game VS computer' },
  56                     'class': {
  57                         "tooltip":true,
  58                         "bottom": true,
  59                         "playing": this.mode == "computer",
  60                         "small": smallScreen,
  61                     },
  62                 },
  63                 [h('i', { 'class': { "material-icons": true } }, "computer")])
  64             );
  65         }
  66         if (["idle","friend"].includes(this.mode))
  67         {
  68             actionArray.push(
  69                 h('button',
  70                 {
  71                     on: { click: this.clickFriendGame },
  72                     attrs: { "aria-label": 'New IRL game' },
  73                     'class': {
  74                         "tooltip":true,
  75                         "bottom": true,
  76                         "playing": this.mode == "friend",
  77                         "small": smallScreen,
  78                     },
  79                 },
  80                 [h('i', { 'class': { "material-icons": true } }, "people")])
  81             );
  82         }
  83         if (!!this.vr)
  84         {
  85             const square00 = document.getElementById("sq-0-0");
  86             const squareWidth = !!square00
  87                 ? parseFloat(window.getComputedStyle(square00).width.slice(0,-2))
  88                 : 0;
  89             const indicWidth = (squareWidth>0 ? squareWidth/2 : 20);
  90             if (this.mode == "human")
  91             {
  92                 let connectedIndic = h(
  93                     'div',
  94                     {
  95                         "class": {
  96                             "topindicator": true,
  97                             "indic-left": true,
  98                             "connected": this.oppConnected,
  99                             "disconnected": !this.oppConnected,
 100                         },
 101                         style: {
 102                             "width": indicWidth + "px",
 103                             "height": indicWidth + "px",
 104                         },
 105                     }
 106                 );
 107                 elementArray.push(connectedIndic);
 108             }
 109             let turnIndic = h(
 110                 'div',
 111                 {
 112                     "class": {
 113                         "topindicator": true,
 114                         "indic-right": true,
 115                         "white-turn": this.vr.turn=="w",
 116                         "black-turn": this.vr.turn=="b",
 117                     },
 118                     style: {
 119                         "width": indicWidth + "px",
 120                         "height": indicWidth + "px",
 121                     },
 122                 }
 123             );
 124             elementArray.push(turnIndic);
 125             let expertSwitch = h(
 126                 'button',
 127                 {
 128                     on: { click: this.toggleExpertMode },
 129                     attrs: { "aria-label": 'Toggle expert mode' },
 130                     'class': {
 131                         "tooltip":true,
 132                         "topindicator": true,
 133                         "indic-right": true,
 134                         "expert-switch": true,
 135                         "expert-mode": this.expert,
 136                         "small": smallScreen,
 137                     },
 138                 },
 139                 [h('i', { 'class': { "material-icons": true } }, "visibility_off")]
 140             );
 141             elementArray.push(expertSwitch);
 142             let choices = h('div',
 143                 {
 144                     attrs: { "id": "choices" },
 145                     'class': { 'row': true },
 146                     style: {
 147                         "display": this.choices.length>0?"block":"none",
 148                         "top": "-" + ((sizeY/2)*squareWidth+squareWidth/2) + "px",
 149                         "width": (this.choices.length * squareWidth) + "px",
 150                         "height": squareWidth + "px",
 151                     },
 152                 },
 153                 this.choices.map( m => { //a "choice" is a move
 154                     return h('div',
 155                         {
 156                             'class': {
 157                                 'board': true,
 158                                 ['board'+sizeY]: true,
 159                             },
 160                             style: {
 161                                 'width': (100/this.choices.length) + "%",
 162                                 'padding-bottom': (100/this.choices.length) + "%",
 163                             },
 164                         },
 165                         [h('img',
 166                             {
 167                                 attrs: { "src": '/images/pieces/' +
 168                                     VariantRules.getPpath(m.appear[0].c+m.appear[0].p) + '.svg' },
 169                                 'class': { 'choice-piece': true },
 170                                 on: { "click": e => { this.play(m); this.choices=[]; } },
 171                             })
 172                         ]
 173                     );
 174                 })
 175             );
 176             // Create board element (+ reserves if needed by variant or mode)
 177             let gameDiv = h('div',
 178                 {
 179                     'class': { 'game': true },
 180                 },
 181                 [_.range(sizeX).map(i => {
 182                     let ci = this.mycolor=='w' ? i : sizeX-i-1;
 183                     return h(
 184                         'div',
 185                         {
 186                             'class': {
 187                                 'row': true,
 188                             },
 189                             style: { 'opacity': this.choices.length>0?"0.5":"1" },
 190                         },
 191                         _.range(sizeY).map(j => {
 192                             let cj = this.mycolor=='w' ? j : sizeY-j-1;
 193                             let elems = [];
 194                             if (this.vr.board[ci][cj] != VariantRules.EMPTY)
 195                             {
 196                                 elems.push(
 197                                     h(
 198                                         'img',
 199                                         {
 200                                             'class': {
 201                                                 'piece': true,
 202                                                 'ghost': !!this.selectedPiece
 203                                                     && this.selectedPiece.parentNode.id == "sq-"+ci+"-"+cj,
 204                                             },
 205                                             attrs: {
 206                                                 src: "/images/pieces/" +
 207                                                     VariantRules.getPpath(this.vr.board[ci][cj]) + ".svg",
 208                                             },
 209                                         }
 210                                     )
 211                                 );
 212                             }
 213                             if (!this.expert && hintSquares[ci][cj])
 214                             {
 215                                 elems.push(
 216                                     h(
 217                                         'img',
 218                                         {
 219                                             'class': {
 220                                                 'mark-square': true,
 221                                             },
 222                                             attrs: {
 223                                                 src: "/images/mark.svg",
 224                                             },
 225                                         }
 226                                     )
 227                                 );
 228                             }
 229                             const lm = this.vr.lastMove;
 230                             const showLight = !this.expert &&
 231                                 (this.mode!="idle" || this.cursor==this.vr.moves.length);
 232                             return h(
 233                                 'div',
 234                                 {
 235                                     'class': {
 236                                         'board': true,
 237                                         ['board'+sizeY]: true,
 238                                         'light-square': (i+j)%2==0,
 239                                         'dark-square': (i+j)%2==1,
 240                                         'highlight': showLight && !!lm && _.isMatch(lm.end, {x:ci,y:cj}),
 241                                         'incheck': showLight && incheckSq[ci][cj],
 242                                     },
 243                                     attrs: {
 244                                         id: this.getSquareId({x:ci,y:cj}),
 245                                     },
 246                                 },
 247                                 elems
 248                             );
 249                         })
 250                     );
 251                 }), choices]
 252             );
 253             if (this.mode != "idle")
 254             {
 255                 actionArray.push(
 256                     h('button',
 257                         {
 258                             on: { click: this.resign },
 259                             attrs: { "aria-label": 'Resign' },
 260                             'class': {
 261                                 "tooltip":true,
 262                                 "bottom": true,
 263                                 "small": smallScreen,
 264                             },
 265                         },
 266                         [h('i', { 'class': { "material-icons": true } }, "flag")])
 267                 );
 268             }
 269             else if (this.vr.moves.length > 0)
 270             {
 271                 // A game finished, and another is not started yet: allow navigation
 272                 actionArray = actionArray.concat([
 273                     h('button',
 274                         {
 275                             on: { click: e => this.undo() },
 276                             attrs: { "aria-label": 'Undo' },
 277                             "class": {
 278                                 "small": smallScreen,
 279                                 "marginleft": true,
 280                             },
 281                         },
 282                         [h('i', { 'class': { "material-icons": true } }, "fast_rewind")]),
 283                     h('button',
 284                         {
 285                             on: { click: e => this.play() },
 286                             attrs: { "aria-label": 'Play' },
 287                             "class": { "small": smallScreen },
 288                         },
 289                         [h('i', { 'class': { "material-icons": true } }, "fast_forward")]),
 290                     ]
 291                 );
 292             }
 293             if (this.mode == "friend")
 294             {
 295                 actionArray = actionArray.concat(
 296                 [
 297                     h('button',
 298                         {
 299                             on: { click: this.undoInGame },
 300                             attrs: { "aria-label": 'Undo' },
 301                             "class": {
 302                                 "small": smallScreen,
 303                                 "marginleft": true,
 304                             },
 305                         },
 306                         [h('i', { 'class': { "material-icons": true } }, "undo")]
 307                     ),
 308                     h('button',
 309                         {
 310                             on: { click: () => { this.mycolor = this.vr.getOppCol(this.mycolor) } },
 311                             attrs: { "aria-label": 'Flip' },
 312                             "class": { "small": smallScreen },
 313                         },
 314                         [h('i', { 'class': { "material-icons": true } }, "cached")]
 315                     ),
 316                 ]);
 317             }
 318             elementArray.push(gameDiv);
 319             if (!!this.vr.reserve)
 320             {
 321                 const shiftIdx = (this.mycolor=="w" ? 0 : 1);
 322                 let myReservePiecesArray = [];
 323                 for (let i=0; i<VariantRules.RESERVE_PIECES.length; i++)
 324                 {
 325                     myReservePiecesArray.push(h('div',
 326                     {
 327                         'class': {'board':true, ['board'+sizeY]:true},
 328                         attrs: { id: this.getSquareId({x:sizeX+shiftIdx,y:i}) }
 329                     },
 330                     [
 331                         h('img',
 332                         {
 333                             'class': {"piece":true},
 334                             attrs: {
 335                                 "src": "/images/pieces/" +
 336                                     this.vr.getReservePpath(this.mycolor,i) + ".svg",
 337                             }
 338                         }),
 339                         h('sup',
 340                             {"class": { "reserve-count": true } },
 341                             [ this.vr.reserve[this.mycolor][VariantRules.RESERVE_PIECES[i]] ]
 342                         )
 343                     ]));
 344                 }
 345                 let oppReservePiecesArray = [];
 346                 const oppCol = this.vr.getOppCol(this.mycolor);
 347                 for (let i=0; i<VariantRules.RESERVE_PIECES.length; i++)
 348                 {
 349                     oppReservePiecesArray.push(h('div',
 350                     {
 351                         'class': {'board':true, ['board'+sizeY]:true},
 352                         attrs: { id: this.getSquareId({x:sizeX+(1-shiftIdx),y:i}) }
 353                     },
 354                     [
 355                         h('img',
 356                         {
 357                             'class': {"piece":true},
 358                             attrs: {
 359                                 "src": "/images/pieces/" +
 360                                     this.vr.getReservePpath(oppCol,i) + ".svg",
 361                             }
 362                         }),
 363                         h('sup',
 364                             {"class": { "reserve-count": true } },
 365                             [ this.vr.reserve[oppCol][VariantRules.RESERVE_PIECES[i]] ]
 366                         )
 367                     ]));
 368                 }
 369                 let reserves = h('div',
 370                     {
 371                         'class':{
 372                             'game': true,
 373                             "reserve-div": true,
 374                         },
 375                     },
 376                     [
 377                         h('div',
 378                             {
 379                                 'class': {
 380                                     'row': true,
 381                                     "reserve-row-1": true,
 382                                 },
 383                             },
 384                             myReservePiecesArray
 385                         ),
 386                         h('div',
 387                             { 'class': { 'row': true }},
 388                             oppReservePiecesArray
 389                         )
 390                     ]
 391                 );
 392                 elementArray.push(reserves);
 393             }
 394             const eogMessage = this.getEndgameMessage(this.score);
 395             const modalEog = [
 396                 h('input',
 397                     {
 398                         attrs: { "id": "modal-eog", type: "checkbox" },
 399                         "class": { "modal": true },
 400                     }),
 401                 h('div',
 402                     {
 403                         attrs: { "role": "dialog", "aria-labelledby": "modal-eog" },
 404                     },
 405                     [
 406                         h('div',
 407                             {
 408                                 "class": { "card": true, "smallpad": true },
 409                             },
 410                             [
 411                                 h('label',
 412                                     {
 413                                         attrs: { "for": "modal-eog" },
 414                                         "class": { "modal-close": true },
 415                                     }
 416                                 ),
 417                                 h('h3',
 418                                     {
 419                                         "class": { "section": true },
 420                                         domProps: { innerHTML: eogMessage },
 421                                     }
 422                                 )
 423                             ]
 424                         )
 425                     ]
 426                 )
 427             ];
 428             elementArray = elementArray.concat(modalEog);
 429         }
 430         const modalNewgame = [
 431             h('input',
 432                 {
 433                     attrs: { "id": "modal-newgame", type: "checkbox" },
 434                     "class": { "modal": true },
 435                 }),
 436             h('div',
 437                 {
 438                     attrs: { "role": "dialog", "aria-labelledby": "modal-newgame" },
 439                 },
 440                 [
 441                     h('div',
 442                         {
 443                             "class": { "card": true, "smallpad": true },
 444                         },
 445                         [
 446                             h('label',
 447                                 {
 448                                     attrs: { "id": "close-newgame", "for": "modal-newgame" },
 449                                     "class": { "modal-close": true },
 450                                 }
 451                             ),
 452                             h('h3',
 453                                 {
 454                                     "class": { "section": true },
 455                                     domProps: { innerHTML: "New game" },
 456                                 }
 457                             ),
 458                             h('p',
 459                                 {
 460                                     "class": { "section": true },
 461                                     domProps: { innerHTML: "Waiting for opponent..." },
 462                                 }
 463                             )
 464                         ]
 465                     )
 466                 ]
 467             )
 468         ];
 469         elementArray = elementArray.concat(modalNewgame);
 470         const modalFenEdit = [
 471             h('input',
 472                 {
 473                     attrs: { "id": "modal-fenedit", type: "checkbox" },
 474                     "class": { "modal": true },
 475                 }),
 476             h('div',
 477                 {
 478                     attrs: { "role": "dialog", "aria-labelledby": "modal-fenedit" },
 479                 },
 480                 [
 481                     h('div',
 482                         {
 483                             "class": { "card": true, "smallpad": true },
 484                         },
 485                         [
 486                             h('label',
 487                                 {
 488                                     attrs: { "id": "close-fenedit", "for": "modal-fenedit" },
 489                                     "class": { "modal-close": true },
 490                                 }
 491                             ),
 492                             h('h3',
 493                                 {
 494                                     "class": { "section": true },
 495                                     domProps: { innerHTML: "Position + flags (FEN):" },
 496                                 }
 497                             ),
 498                             h('input',
 499                                 {
 500                                     attrs: {
 501                                         "id": "input-fen",
 502                                         type: "text",
 503                                         value: VariantRules.GenRandInitFen(),
 504                                     },
 505                                 }
 506                             ),
 507                             h('button',
 508                                 {
 509                                     on: { click:
 510                                         () => {
 511                                             const fen = document.getElementById("input-fen").value;
 512                                             document.getElementById("modal-fenedit").checked = false;
 513                                             this.newGame("friend", fen);
 514                                         }
 515                                     },
 516                                     domProps: { innerHTML: "Ok" },
 517                                 }
 518                             ),
 519                             h('button',
 520                                 {
 521                                     on: { click:
 522                                         () => {
 523                                             document.getElementById("input-fen").value =
 524                                                 VariantRules.GenRandInitFen();
 525                                         }
 526                                     },
 527                                     domProps: { innerHTML: "Random" },
 528                                 }
 529                             ),
 530                         ]
 531                     )
 532                 ]
 533             )
 534         ];
 535         elementArray = elementArray.concat(modalFenEdit);
 536         const actions = h('div',
 537             {
 538                 attrs: { "id": "actions" },
 539                 'class': { 'text-center': true },
 540             },
 541             actionArray
 542         );
 543         elementArray.push(actions);
 544         if (this.score != "*")
 545         {
 546             elementArray.push(
 547                 h('div',
 548                     { attrs: { id: "pgn-div" } },
 549                     [
 550                         h('a',
 551                             {
 552                                 attrs: {
 553                                     id: "download",
 554                                     href: "#",
 555                                 }
 556                             }
 557                         ),
 558                         h('p',
 559                             {
 560                                 attrs: { id: "pgn-game" },
 561                                 on: { click: this.download },
 562                                 domProps: { innerHTML: this.pgnTxt }
 563                             }
 564                         )
 565                     ]
 566                 )
 567             );
 568         }
 569         else if (this.mode != "idle")
 570         {
 571             // Show current FEN
 572             elementArray.push(
 573                 h('div',
 574                     { attrs: { id: "fen-div" } },
 575                     [
 576                         h('p',
 577                             {
 578                                 attrs: { id: "fen-string" },
 579                                 domProps: { innerHTML: this.vr.getFen() }
 580                             }
 581                         )
 582                     ]
 583                 )
 584             );
 585         }
 586         return h(
 587             'div',
 588             {
 589                 'class': {
 590                     "col-sm-12":true,
 591                     "col-md-8":true,
 592                     "col-md-offset-2":true,
 593                     "col-lg-6":true,
 594                     "col-lg-offset-3":true,
 595                 },
 596                 // NOTE: click = mousedown + mouseup
 597                 on: {
 598                     mousedown: this.mousedown,
 599                     mousemove: this.mousemove,
 600                     mouseup: this.mouseup,
 601                     touchstart: this.mousedown,
 602                     touchmove: this.mousemove,
 603                     touchend: this.mouseup,
 604                 },
 605             },
 606             elementArray
 607         );
 608     },
 609     created: function() {
 610         const url = socketUrl;
 611         const continuation = (localStorage.getItem("variant") === variant);
 612         this.myid = continuation ? localStorage.getItem("myid") : getRandString();
 613         if (!continuation)
 614         {
 615             // HACK: play a small silent sound to allow "new game" sound later
 616             // if tab not focused (TODO: does it really work ?!)
 617             new Audio("/sounds/silent.mp3").play().then(() => {}).catch(err => {});
 618         }
 619         this.conn = new WebSocket(url + "/?sid=" + this.myid + "&page=" + variant);
 620         const socketOpenListener = () => {
 621             if (continuation)
 622             {
 623                 const fen = localStorage.getItem("fen");
 624                 const mycolor = localStorage.getItem("mycolor");
 625                 const oppid = localStorage.getItem("oppid");
 626                 const moves = JSON.parse(localStorage.getItem("moves"));
 627                 this.newGame("human", fen, mycolor, oppid, moves, true);
 628                 // Send ping to server (answer pong if opponent is connected)
 629                 this.conn.send(JSON.stringify({code:"ping",oppid:this.oppid}));
 630             }
 631             else if (localStorage.getItem("newgame") === variant)
 632             {
 633                 // New game request has been cancelled on disconnect
 634                 this.newGame("human", undefined, undefined, undefined, undefined, "reconnect");
 635             }
 636         };
 637         const socketMessageListener = msg => {
 638             const data = JSON.parse(msg.data);
 639             switch (data.code)
 640             {
 641                 case "newgame": //opponent found
 642                     // oppid: opponent socket ID
 643                     this.newGame("human", data.fen, data.color, data.oppid);
 644                     break;
 645                 case "newmove": //..he played!
 646                     this.play(data.move, "animate");
 647                     break;
 648                 case "pong": //received if we sent a ping (game still alive on our side)
 649                     this.oppConnected = true;
 650                     const L = this.vr.moves.length;
 651                     // Send our "last state" informations to opponent
 652                     this.conn.send(JSON.stringify({
 653                         code:"lastate",
 654                         oppid:this.oppid,
 655                         lastMove:L>0?this.vr.moves[L-1]:undefined,
 656                         movesCount:L,
 657                     }));
 658                     break;
 659                 case "lastate": //got opponent infos about last move (we might have resigned)
 660                     if (this.mode!="human" || this.oppid!=data.oppid)
 661                     {
 662                         // OK, we resigned
 663                         this.conn.send(JSON.stringify({
 664                             code:"lastate",
 665                             oppid:this.oppid,
 666                             lastMove:undefined,
 667                             movesCount:-1,
 668                         }));
 669                     }
 670                     else if (data.movesCount < 0)
 671                     {
 672                         // OK, he resigned
 673                         this.endGame(this.mycolor=="w"?"1-0":"0-1");
 674                     }
 675                     else if (data.movesCount < this.vr.moves.length)
 676                     {
 677                         // We must tell last move to opponent
 678                         const L = this.vr.moves.length;
 679                         this.conn.send(JSON.stringify({
 680                             code:"lastate",
 681                             oppid:this.oppid,
 682                             lastMove:this.vr.moves[L-1],
 683                             movesCount:L,
 684                         }));
 685                     }
 686                     else if (data.movesCount > this.vr.moves.length) //just got last move from him
 687                         this.play(data.lastMove, "animate");
 688                     break;
 689                 case "resign": //..you won!
 690                     this.endGame(this.mycolor=="w"?"1-0":"0-1");
 691                     break;
 692                 // TODO: also use (dis)connect info to count online players?
 693                 case "connect":
 694                 case "disconnect":
 695                     if (this.mode == "human" && this.oppid == data.id)
 696                         this.oppConnected = (data.code == "connect");
 697                     break;
 698             }
 699         };
 700         const socketCloseListener = () => {
 701             this.conn = new WebSocket(url + "/?sid=" + this.myid + "&page=" + variant);
 702             this.conn.addEventListener('open', socketOpenListener);
 703             this.conn.addEventListener('message', socketMessageListener);
 704             this.conn.addEventListener('close', socketCloseListener);
 705         };
 706         this.conn.onopen = socketOpenListener;
 707         this.conn.onmessage = socketMessageListener;
 708         this.conn.onclose = socketCloseListener;
 709         // Listen to keyboard left/right to navigate in game
 710         document.onkeydown = event => {
 711             if (this.mode == "idle" && !!this.vr && this.vr.moves.length > 0
 712                 && [37,39].includes(event.keyCode))
 713             {
 714                 event.preventDefault();
 715                 if (event.keyCode == 37) //Back
 716                     this.undo();
 717                 else //Forward (39)
 718                     this.play();
 719             }
 720         };
 721     },
 722     methods: {
 723         download: function() {
 724             let content = document.getElementById("pgn-game").innerHTML;
 725             content = content.replace(/<br>/g, "\n");
 726             // Prepare and trigger download link
 727             let downloadAnchor = document.getElementById("download");
 728             downloadAnchor.setAttribute("download", "game.pgn");
 729             downloadAnchor.href = "data:text/plain;charset=utf-8," +
 730                 encodeURIComponent(content);
 731             downloadAnchor.click();
 732         },
 733         endGame: function(score) {
 734             this.score = score;
 735             let modalBox = document.getElementById("modal-eog");
 736             modalBox.checked = true;
 737             // Variants may have special PGN structure (so next function isn't defined here)
 738             this.pgnTxt = this.vr.getPGN(this.mycolor, this.score, this.fenStart, this.mode);
 739             setTimeout(() => { modalBox.checked = false; }, 2000);
 740             if (this.mode == "human")
 741                 this.clearStorage();
 742             this.mode = "idle";
 743             this.cursor = this.vr.moves.length; //to navigate in finished game
 744             this.oppid = "";
 745         },
 746         getEndgameMessage: function(score) {
 747             let eogMessage = "Unfinished";
 748             switch (this.score)
 749             {
 750                 case "1-0":
 751                     eogMessage = "White win";
 752                     break;
 753                 case "0-1":
 754                     eogMessage = "Black win";
 755                     break;
 756                 case "1/2":
 757                     eogMessage = "Draw";
 758                     break;
 759             }
 760             return eogMessage;
 761         },
 762         setStorage: function() {
 763             localStorage.setItem("myid", this.myid);
 764             localStorage.setItem("variant", variant);
 765             localStorage.setItem("mycolor", this.mycolor);
 766             localStorage.setItem("oppid", this.oppid);
 767             localStorage.setItem("fenStart", this.fenStart);
 768             localStorage.setItem("moves", JSON.stringify(this.vr.moves));
 769             localStorage.setItem("fen", this.vr.getFen());
 770         },
 771         updateStorage: function() {
 772             localStorage.setItem("moves", JSON.stringify(this.vr.moves));
 773             localStorage.setItem("fen", this.vr.getFen());
 774         },
 775         clearStorage: function() {
 776             delete localStorage["variant"];
 777             delete localStorage["myid"];
 778             delete localStorage["mycolor"];
 779             delete localStorage["oppid"];
 780             delete localStorage["fenStart"];
 781             delete localStorage["fen"];
 782             delete localStorage["moves"];
 783         },
 784         // HACK because mini-css tooltips are persistent after click...
 785         getRidOfTooltip: function(elt) {
 786             elt.style.visibility = "hidden";
 787             setTimeout(() => { elt.style.visibility="visible"; }, 100);
 788         },
 789         clickGameSeek: function(e) {
 790             this.getRidOfTooltip(e.currentTarget);
 791             if (this.mode == "human")
 792                 return; //no newgame while playing
 793             if (this.seek)
 794             {
 795                 this.conn.send(JSON.stringify({code:"cancelnewgame"}));
 796                 delete localStorage["newgame"]; //cancel game seek
 797                 this.seek = false;
 798             }
 799             else
 800                 this.newGame("human");
 801         },
 802         clickComputerGame: function(e) {
 803             this.getRidOfTooltip(e.currentTarget);
 804             if (this.mode == "human")
 805                 return; //no newgame while playing
 806             this.newGame("computer");
 807         },
 808         clickFriendGame: function(e) {
 809             this.getRidOfTooltip(e.currentTarget);
 810             document.getElementById("modal-fenedit").checked = true;
 811         },
 812         toggleExpertMode: function(e) {
 813             this.getRidOfTooltip(e.currentTarget);
 814             this.expert = !this.expert;
 815             setCookie("expert", this.expert ? "1" : "0");
 816         },
 817         resign: function(e) {
 818             this.getRidOfTooltip(e.currentTarget);
 819             if (this.mode == "human" && this.oppConnected)
 820             {
 821                 try {
 822                     this.conn.send(JSON.stringify({code: "resign", oppid: this.oppid}));
 823                 } catch (INVALID_STATE_ERR) {
 824                     return; //socket is not ready (and not yet reconnected)
 825                 }
 826             }
 827             this.endGame(this.mycolor=="w"?"0-1":"1-0");
 828         },
 829         newGame: function(mode, fenInit, color, oppId, moves, continuation) {
 830             const fen = fenInit || VariantRules.GenRandInitFen();
 831             console.log(fen); //DEBUG
 832             if (mode=="human" && !oppId)
 833             {
 834                 const storageVariant = localStorage.getItem("variant");
 835                 if (!!storageVariant && storageVariant !== variant)
 836                 {
 837                     alert("Finish your " + storageVariant + " game first!");
 838                     return;
 839                 }
 840                 // Send game request and wait..
 841                 localStorage["newgame"] = variant;
 842                 this.seek = true;
 843                 this.clearStorage(); //in case of
 844                 try {
 845                     this.conn.send(JSON.stringify({code:"newgame", fen:fen}));
 846                 } catch (INVALID_STATE_ERR) {
 847                     return; //nothing achieved
 848                 }
 849                 if (continuation !== "reconnect") //TODO: bad HACK...
 850                 {
 851                     let modalBox = document.getElementById("modal-newgame");
 852                     modalBox.checked = true;
 853                     setTimeout(() => { modalBox.checked = false; }, 2000);
 854                 }
 855                 return;
 856             }
 857             this.vr = new VariantRules(fen, moves || []);
 858             this.score = "*";
 859             this.pgnTxt = ""; //redundant with this.score = "*", but cleaner
 860             this.mode = mode;
 861             this.incheck = []; //in case of
 862             this.fenStart = (continuation ? localStorage.getItem("fenStart") : fen);
 863             if (mode=="human")
 864             {
 865                 // Opponent found!
 866                 if (!continuation)
 867                 {
 868                     // Not playing sound on game continuation:
 869                     new Audio("/sounds/newgame.mp3").play().then(() => {}).catch(err => {});
 870                     document.getElementById("modal-newgame").checked = false;
 871                 }
 872                 this.oppid = oppId;
 873                 this.oppConnected = true;
 874                 this.mycolor = color;
 875                 this.seek = false;
 876                 if (!!moves && moves.length > 0) //imply continuation
 877                 {
 878                     const lastMove = moves[moves.length-1];
 879                     this.vr.undo(lastMove);
 880                     this.incheck = this.vr.getCheckSquares(lastMove);
 881                     this.vr.play(lastMove, "ingame");
 882                 }
 883                 delete localStorage["newgame"];
 884                 this.setStorage(); //in case of interruptions
 885             }
 886             else if (mode == "computer")
 887             {
 888                 this.mycolor = Math.random() < 0.5 ? 'w' : 'b';
 889                 if (this.mycolor == 'b')
 890                     setTimeout(this.playComputerMove, 500);
 891             }
 892             //else: against a (IRL) friend: nothing more to do
 893         },
 894         playComputerMove: function() {
 895             const timeStart = Date.now();
 896             const compMove = this.vr.getComputerMove();
 897             // (first move) HACK: avoid selecting elements before they appear on page:
 898             const delay = Math.max(500-(Date.now()-timeStart), 0);
 899             setTimeout(() => this.play(compMove, "animate"), delay);
 900         },
 901         // Get the identifier of a HTML table cell from its numeric coordinates o.x,o.y.
 902         getSquareId: function(o) {
 903             // NOTE: a separator is required to allow any size of board
 904             return  "sq-" + o.x + "-" + o.y;
 905         },
 906         // Inverse function
 907         getSquareFromId: function(id) {
 908             let idParts = id.split('-');
 909             return [parseInt(idParts[1]), parseInt(idParts[2])];
 910         },
 911         mousedown: function(e) {
 912             e = e || window.event;
 913             let ingame = false;
 914             let elem = e.target;
 915             while (!ingame && elem !== null)
 916             {
 917                 if (elem.classList.contains("game"))
 918                 {
 919                     ingame = true;
 920                     break;
 921                 }
 922                 elem = elem.parentElement;
 923             }
 924             if (!ingame) //let default behavior (click on button...)
 925                 return;
 926             e.preventDefault(); //disable native drag & drop
 927             if (!this.selectedPiece && e.target.classList.contains("piece"))
 928             {
 929                 // Next few lines to center the piece on mouse cursor
 930                 let rect = e.target.parentNode.getBoundingClientRect();
 931                 this.start = {
 932                     x: rect.x + rect.width/2,
 933                     y: rect.y + rect.width/2,
 934                     id: e.target.parentNode.id
 935                 };
 936                 this.selectedPiece = e.target.cloneNode();
 937                 this.selectedPiece.style.position = "absolute";
 938                 this.selectedPiece.style.top = 0;
 939                 this.selectedPiece.style.display = "inline-block";
 940                 this.selectedPiece.style.zIndex = 3000;
 941                 let startSquare = this.getSquareFromId(e.target.parentNode.id);
 942                 const iCanPlay = this.mode!="idle"
 943                     && (this.mode=="friend" || this.vr.canIplay(this.mycolor,startSquare));
 944                 this.possibleMoves = iCanPlay ? this.vr.getPossibleMovesFrom(startSquare) : [];
 945                 // Next line add moving piece just after current image
 946                 // (required for Crazyhouse reserve)
 947                 e.target.parentNode.insertBefore(this.selectedPiece, e.target.nextSibling);
 948             }
 949         },
 950         mousemove: function(e) {
 951             if (!this.selectedPiece)
 952                 return;
 953             e = e || window.event;
 954             // If there is an active element, move it around
 955             if (!!this.selectedPiece)
 956             {
 957                 const [offsetX,offsetY] = !!e.clientX
 958                     ? [e.clientX,e.clientY] //desktop browser
 959                     : [e.changedTouches[0].pageX, e.changedTouches[0].pageY]; //smartphone
 960                 this.selectedPiece.style.left = (offsetX-this.start.x) + "px";
 961                 this.selectedPiece.style.top = (offsetY-this.start.y) + "px";
 962             }
 963         },
 964         mouseup: function(e) {
 965             if (!this.selectedPiece)
 966                 return;
 967             e = e || window.event;
 968             // Read drop target (or parentElement, parentNode... if type == "img")
 969             this.selectedPiece.style.zIndex = -3000; //HACK to find square from final coords
 970             const [offsetX,offsetY] = !!e.clientX
 971                 ? [e.clientX,e.clientY]
 972                 : [e.changedTouches[0].pageX, e.changedTouches[0].pageY];
 973             let landing = document.elementFromPoint(offsetX, offsetY);
 974             this.selectedPiece.style.zIndex = 3000;
 975             // Next condition: classList.contains(piece) fails because of marks
 976             while (landing.tagName == "IMG")
 977                 landing = landing.parentNode;
 978             if (this.start.id == landing.id)
 979             {
 980                 // A click: selectedPiece and possibleMoves are already filled
 981                 return;
 982             }
 983             // OK: process move attempt
 984             let endSquare = this.getSquareFromId(landing.id);
 985             let moves = this.findMatchingMoves(endSquare);
 986             this.possibleMoves = [];
 987             if (moves.length > 1)
 988                 this.choices = moves;
 989             else if (moves.length==1)
 990                 this.play(moves[0]);
 991             // Else: impossible move
 992             this.selectedPiece.parentNode.removeChild(this.selectedPiece);
 993             delete this.selectedPiece;
 994             this.selectedPiece = null;
 995         },
 996         findMatchingMoves: function(endSquare) {
 997             // Run through moves list and return the matching set (if promotions...)
 998             let moves = [];
 999             this.possibleMoves.forEach(function(m) {
1000                 if (endSquare[0] == m.end.x && endSquare[1] == m.end.y)
1001                     moves.push(m);
1002             });
1003             return moves;
1004         },
1005         animateMove: function(move) {
1006             let startSquare = document.getElementById(this.getSquareId(move.start));
1007             let endSquare = document.getElementById(this.getSquareId(move.end));
1008             let rectStart = startSquare.getBoundingClientRect();
1009             let rectEnd = endSquare.getBoundingClientRect();
1010             let translation = {x:rectEnd.x-rectStart.x, y:rectEnd.y-rectStart.y};
1011             let movingPiece =
1012                 document.querySelector("#" + this.getSquareId(move.start) + " > img.piece");
1013             // HACK for animation (with positive translate, image slides "under background")
1014             // Possible improvement: just alter squares on the piece's way...
1015             squares = document.getElementsByClassName("board");
1016             for (let i=0; i<squares.length; i++)
1017             {
1018                 let square = squares.item(i);
1019                 if (square.id != this.getSquareId(move.start))
1020                     square.style.zIndex = "-1";
1021             }
1022             movingPiece.style.transform = "translate(" + translation.x + "px," +
1023                 translation.y + "px)";
1024             movingPiece.style.transitionDuration = "0.2s";
1025             movingPiece.style.zIndex = "3000";
1026             setTimeout( () => {
1027                 for (let i=0; i<squares.length; i++)
1028                     squares.item(i).style.zIndex = "auto";
1029                 movingPiece.style = {}; //required e.g. for 0-0 with KR swap
1030                 this.play(move);
1031             }, 200);
1032         },
1033         play: function(move, programmatic) {
1034             if (!move)
1035             {
1036                 // Navigate after game is over
1037                 if (this.cursor >= this.vr.moves.length)
1038                     return; //already at the end
1039                 move = this.vr.moves[this.cursor++];
1040             }
1041             if (!!programmatic) //computer or human opponent
1042             {
1043                 this.animateMove(move);
1044                 return;
1045             }
1046             // Not programmatic, or animation is over
1047             if (this.mode == "human" && this.vr.turn == this.mycolor)
1048                 this.conn.send(JSON.stringify({code:"newmove", move:move, oppid:this.oppid}));
1049             new Audio("/sounds/chessmove1.mp3").play().then(() => {}).catch(err => {});
1050             if (this.mode != "idle")
1051             {
1052                 this.incheck = this.vr.getCheckSquares(move); //is opponent in check?
1053                 this.vr.play(move, "ingame");
1054             }
1055             else
1056             {
1057                 VariantRules.PlayOnBoard(this.vr.board, move);
1058                 this.$forceUpdate(); //TODO: ?!
1059             }
1060             if (this.mode == "human")
1061                 this.updateStorage(); //after our moves and opponent moves
1062             if (this.mode != "idle")
1063             {
1064                 const eog = this.vr.checkGameOver();
1065                 if (eog != "*")
1066                     this.endGame(eog);
1067             }
1068             if (this.mode == "computer" && this.vr.turn != this.mycolor)
1069                 setTimeout(this.playComputerMove, 500);
1070         },
1071         undo: function() {
1072             // Navigate after game is over
1073             if (this.cursor == 0)
1074                 return; //already at the beginning
1075             if (this.cursor == this.vr.moves.length)
1076                 this.incheck = []; //in case of...
1077             const move = this.vr.moves[--this.cursor];
1078             VariantRules.UndoOnBoard(this.vr.board, move);
1079             this.$forceUpdate(); //TODO: ?!
1080         },
1081         undoInGame: function() {
1082             const lm = this.vr.lastMove;
1083             if (!!lm)
1084                 this.vr.undo(lm);
1085         },
1086     },
1087 })