client/src/components/Board.vue

   1 <script>
   2 import { getSquareId, getSquareFromId } from "@/utils/squareId";
   3 import { ArrayFun } from "@/utils/array";
   4 import { store } from "@/store";
   5 export default {
   6   name: "my-board",
   7   // Last move cannot be guessed from here, and is required for highlights.
   8   // vr: object to check moves, print board...
   9   // userColor is left undefined for an external observer
  10   props: [
  11     "vr",
  12     "lastMove",
  13     "analyze",
  14     "score",
  15     "incheck",
  16     "orientation",
  17     "userColor",
  18     "vname"
  19   ],
  20   data: function() {
  21     return {
  22       mobileBrowser: ("ontouchstart" in window),
  23       possibleMoves: [], //filled after each valid click/dragstart
  24       choices: [], //promotion pieces, or checkered captures... (as moves)
  25       containerPos: null,
  26       selectedPiece: null, //moving piece (or clicked piece)
  27       start: null, //pixels coordinates + id of starting square (click or drag)
  28       startArrow: null,
  29       movingArrow: null,
  30       arrows: [], //object of {start: x,y / end: x,y}
  31       circles: {}, //object of squares' ID --> true (TODO: use a set?)
  32       click: "",
  33       clickTime: 0,
  34       settings: store.state.settings
  35     };
  36   },
  37   render(h) {
  38     if (!this.vr) {
  39       // Return empty div of class 'game' to avoid error when setting size
  40       return h(
  41         "div",
  42         { "class": { game: true } }
  43       );
  44     }
  45     const [sizeX, sizeY] = [V.size.x, V.size.y];
  46     // Precompute hints squares to facilitate rendering
  47     let hintSquares = ArrayFun.init(sizeX, sizeY, false);
  48     this.possibleMoves.forEach(m => {
  49       hintSquares[m.end.x][m.end.y] = true;
  50     });
  51     // Also precompute in-check squares
  52     let incheckSq = ArrayFun.init(sizeX, sizeY, false);
  53     this.incheck.forEach(sq => {
  54       incheckSq[sq[0]][sq[1]] = true;
  55     });
  56
  57     let lm = this.lastMove;
  58     // Precompute lastMove highlighting squares
  59     const lmHighlights = {};
  60     if (!!lm) {
  61       if (!Array.isArray(lm)) lm = [lm];
  62       lm.forEach(m => {
  63         if (V.OnBoard(m.start.x, m.start.y))
  64           lmHighlights[m.start.x + sizeX * m.start.y] = true;
  65         if (V.OnBoard(m.end.x, m.end.y))
  66           lmHighlights[m.end.x + sizeX * m.end.y] = true;
  67       });
  68     }
  69     const showLight = (
  70       this.settings.highlight &&
  71       ["all","highlight"].includes(V.ShowMoves)
  72     );
  73     const showCheck = (
  74       this.settings.highlight &&
  75       ["all","highlight","byrow"].includes(V.ShowMoves)
  76     );
  77     const orientation = !V.CanFlip ? "w" : this.orientation;
  78     // Ensure that squares colors do not change when board is flipped
  79     const lightSquareMod = (sizeX + sizeY) % 2;
  80     const showPiece = (x, y) => {
  81       return (
  82         this.vr.board[x][y] != V.EMPTY &&
  83         (!this.vr.enlightened || this.analyze || this.score != "*" ||
  84           (!!this.userColor && this.vr.enlightened[this.userColor][x][y]))
  85       );
  86     };
  87     const inHighlight = (x, y) => {
  88       return showLight && !!lmHighlights[x + sizeX * y];
  89     };
  90     const inShadow = (x, y) => {
  91       return (
  92         !this.analyze &&
  93         this.score == "*" &&
  94         this.vr.enlightened &&
  95         (!this.userColor || !this.vr.enlightened[this.userColor][x][y])
  96       );
  97     };
  98     // Create board element (+ reserves if needed by variant)
  99     let elementArray = [];
 100     const gameDiv = h(
 101       "div",
 102       {
 103         attrs: { id: "gamePosition" },
 104         "class": {
 105           game: true,
 106           clearer: true
 107         }
 108       },
 109       [...Array(sizeX).keys()].map(i => {
 110         const ci = orientation == "w" ? i : sizeX - i - 1;
 111         return h(
 112           "div",
 113           {
 114             "class": {
 115               row: true
 116             },
 117             style: { opacity: this.choices.length > 0 ? "0.5" : "1" }
 118           },
 119           [...Array(sizeY).keys()].map(j => {
 120             const cj = orientation == "w" ? j : sizeY - j - 1;
 121             const squareId = "sq-" + ci + "-" + cj;
 122             let elems = [];
 123             if (showPiece(ci, cj)) {
 124               let pieceSpecs = {
 125                 "class": {
 126                   piece: true,
 127                   ghost:
 128                     !!this.selectedPiece &&
 129                     this.selectedPiece.parentNode.id == squareId
 130                 },
 131                 attrs: {
 132                   src:
 133                     "/images/pieces/" +
 134                     this.vr.getPpath(
 135                       this.vr.board[ci][cj],
 136                       // Extra args useful for some variants:
 137                       this.userColor,
 138                       this.score,
 139                       this.orientation) +
 140                     V.IMAGE_EXTENSION
 141                 }
 142               };
 143               if (this.arrows.length == 0)
 144                 pieceSpecs["style"] = { position: "absolute" };
 145               elems.push(h("img", pieceSpecs));
 146             }
 147             if (this.settings.hints && hintSquares[ci][cj]) {
 148               elems.push(
 149                 h("img", {
 150                   "class": {
 151                     "mark-square": true
 152                   },
 153                   attrs: {
 154                     src: "/images/mark.svg"
 155                   }
 156                 })
 157               );
 158             }
 159             if (!!this.circles[squareId]) {
 160               elems.push(
 161                 h("img", {
 162                   "class": {
 163                     "circle-square": true
 164                   },
 165                   attrs: {
 166                     src: "/images/circle.svg"
 167                   }
 168                 })
 169               );
 170             }
 171             const lightSquare = (ci + cj) % 2 == lightSquareMod;
 172             return h(
 173               "div",
 174               {
 175                 "class": {
 176                   board: true,
 177                   ["board" + sizeY]: true,
 178                   "light-square":
 179                     !V.Notoodark && lightSquare && !V.Monochrome,
 180                   "dark-square":
 181                     !V.Notoodark && (!lightSquare || !!V.Monochrome),
 182                   "middle-square": V.Notoodark,
 183                   [this.settings.bcolor]: true,
 184                   "in-shadow": inShadow(ci, cj),
 185                   "highlight-light": inHighlight(ci, cj) && lightSquare,
 186                   "highlight-dark":
 187                     inHighlight(ci, cj) && (V.Monochrome || !lightSquare),
 188                   "incheck-light":
 189                     showCheck && lightSquare && incheckSq[ci][cj],
 190                   "incheck-dark":
 191                     showCheck && !lightSquare && incheckSq[ci][cj]
 192                 },
 193                 attrs: {
 194                   id: getSquareId({ x: ci, y: cj })
 195                 }
 196               },
 197               elems
 198             );
 199           })
 200         );
 201       })
 202     );
 203     if (!!this.vr.reserve) {
 204       const playingColor = this.userColor || "w"; //default for an observer
 205       const shiftIdx = playingColor == "w" ? 0 : 1;
 206       // Some variants have more than sizeY reserve pieces (Clorange: 10)
 207       const reserveSquareNb = Math.max(sizeY, V.RESERVE_PIECES.length);
 208       let myReservePiecesArray = [];
 209       for (let i = 0; i < V.RESERVE_PIECES.length; i++) {
 210         const qty = this.vr.reserve[playingColor][V.RESERVE_PIECES[i]];
 211         myReservePiecesArray.push(
 212           h(
 213             "div",
 214             {
 215               "class": { board: true, ["board" + reserveSquareNb]: true },
 216               attrs: { id: getSquareId({ x: sizeX + shiftIdx, y: i }) },
 217               style: { opacity: qty > 0 ? 1 : 0.35 }
 218             },
 219             [
 220               h("img", {
 221                 // NOTE: class "reserve" not used currently
 222                 "class": { piece: true, reserve: true },
 223                 attrs: {
 224                   src:
 225                     "/images/pieces/" +
 226                     this.vr.getReservePpath(i, playingColor, orientation) +
 227                     ".svg"
 228                 }
 229               }),
 230               h(
 231                 "sup",
 232                 {
 233                   "class": { "reserve-count": true },
 234                   style: { top: "calc(100% + 5px)" }
 235                 },
 236                 [ qty ]
 237               )
 238             ]
 239           )
 240         );
 241       }
 242       let oppReservePiecesArray = [];
 243       const oppCol = V.GetOppCol(playingColor);
 244       for (let i = 0; i < V.RESERVE_PIECES.length; i++) {
 245         const qty = this.vr.reserve[oppCol][V.RESERVE_PIECES[i]];
 246         oppReservePiecesArray.push(
 247           h(
 248             "div",
 249             {
 250               "class": { board: true, ["board" + reserveSquareNb]: true },
 251               attrs: { id: getSquareId({ x: sizeX + (1 - shiftIdx), y: i }) },
 252               style: { opacity: qty > 0 ? 1 : 0.35 }
 253             },
 254             [
 255               h("img", {
 256                 "class": { piece: true, reserve: true },
 257                 attrs: {
 258                   src:
 259                     "/images/pieces/" +
 260                     this.vr.getReservePpath(i, oppCol, orientation) +
 261                     ".svg"
 262                 }
 263               }),
 264               h(
 265                 "sup",
 266                 {
 267                   "class": { "reserve-count": true },
 268                   style: { top: "calc(100% + 5px)" }
 269                 },
 270                 [ qty ]
 271               )
 272             ]
 273           )
 274         );
 275       }
 276       const myReserveTop = (
 277         (playingColor == 'w' && orientation == 'b') ||
 278         (playingColor == 'b' && orientation == 'w')
 279       );
 280       // Center reserves, assuming same number of pieces for each side:
 281       const nbReservePieces = myReservePiecesArray.length;
 282       const marginLeft =
 283         ((100 - nbReservePieces * (100 / reserveSquareNb)) / 2) + "%";
 284       const reserveTop =
 285         h(
 286           "div",
 287           {
 288             "class": {
 289               game: true,
 290               "reserve-div": true
 291             },
 292             style: {
 293               "margin-left": marginLeft
 294             }
 295           },
 296           [
 297             h(
 298               "div",
 299               {
 300                 "class": {
 301                   row: true,
 302                   "reserve-row": true
 303                 }
 304               },
 305               myReserveTop ? myReservePiecesArray : oppReservePiecesArray
 306             )
 307           ]
 308         );
 309       var reserveBottom =
 310         h(
 311           "div",
 312           {
 313             "class": {
 314               game: true,
 315               "reserve-div": true
 316             },
 317             style: {
 318               "margin-left": marginLeft
 319             }
 320           },
 321           [
 322             h(
 323               "div",
 324               {
 325                 "class": {
 326                   row: true,
 327                   "reserve-row": true
 328                 }
 329               },
 330               myReserveTop ? oppReservePiecesArray : myReservePiecesArray
 331             )
 332           ]
 333         );
 334       elementArray.push(reserveTop);
 335     }
 336     elementArray.push(gameDiv);
 337     if (!!this.vr.reserve) elementArray.push(reserveBottom);
 338     const boardElt = document.getElementById("gamePosition");
 339     // boardElt might be undefine (at first drawing)
 340     if (this.choices.length > 0 && !!boardElt) {
 341       const squareWidth = boardElt.offsetWidth / sizeY;
 342       const offset = [boardElt.offsetTop, boardElt.offsetLeft];
 343       const maxNbeltsPerRow = Math.min(this.choices.length, sizeY);
 344       let topOffset = offset[0] + (sizeY / 2) * squareWidth - squareWidth / 2;
 345       let choicesHeight = squareWidth;
 346       if (this.choices.length >= sizeY) {
 347         // A second row is required (Eightpieces variant)
 348         topOffset -= squareWidth / 2;
 349         choicesHeight *= 2;
 350       }
 351       const choices = h(
 352         "div",
 353         {
 354           attrs: { id: "choices" },
 355           "class": { row: true },
 356           style: {
 357             top: topOffset + "px",
 358             left:
 359               offset[1] +
 360               (squareWidth * Math.max(sizeY - this.choices.length, 0)) / 2 +
 361               "px",
 362             width: (maxNbeltsPerRow * squareWidth) + "px",
 363             height: choicesHeight + "px"
 364           }
 365         },
 366         [ h(
 367           "div",
 368           {
 369             "class": { "full-width": true }
 370           },
 371           this.choices.map(m => {
 372             // A "choice" is a move
 373             const applyMove = (e) => {
 374               e.stopPropagation();
 375               // Force a delay between move is shown and clicked
 376               // (otherwise a "double-click" bug might occur)
 377               if (Date.now() - this.clickTime < 200) return;
 378               this.choices = [];
 379               this.play(m);
 380             };
 381             const onClick =
 382               this.mobileBrowser
 383                 ? { touchend: applyMove }
 384                 : { mouseup: applyMove };
 385             return h(
 386               "div",
 387               {
 388                 "class": {
 389                   board: true,
 390                   ["board" + sizeY]: true
 391                 },
 392                 style: {
 393                   width: (100 / maxNbeltsPerRow) + "%",
 394                   "padding-bottom": (100 / maxNbeltsPerRow) + "%"
 395                 }
 396               },
 397               [
 398                 h("img", {
 399                   attrs: {
 400                     src:
 401                       "/images/pieces/" +
 402                       // orientation: extra arg useful for some variants:
 403                       this.vr.getPPpath(m, this.orientation) +
 404                       V.IMAGE_EXTENSION
 405                   },
 406                   "class": { "choice-piece": true },
 407                   on: onClick
 408                 })
 409               ]
 410             );
 411           })
 412         ) ]
 413       );
 414       elementArray.unshift(choices);
 415     }
 416     let onEvents = {};
 417     // NOTE: click = mousedown + mouseup
 418     if (this.mobileBrowser) {
 419       onEvents = {
 420         on: {
 421           touchstart: this.mousedown,
 422           touchmove: this.mousemove,
 423           touchend: this.mouseup
 424         }
 425       };
 426     } else {
 427       onEvents = {
 428         on: {
 429           mousedown: this.mousedown,
 430           mousemove: this.mousemove,
 431           mouseup: this.mouseup,
 432           contextmenu: this.blockContextMenu
 433         }
 434       };
 435     }
 436     return (
 437       h(
 438         "div",
 439         Object.assign({ attrs: { id: "rootBoardElement" } }, onEvents),
 440         elementArray
 441       )
 442     );
 443   },
 444   updated: function() {
 445     this.re_setDrawings();
 446   },
 447   methods: {
 448     blockContextMenu: function(e) {
 449       e.preventDefault();
 450       e.stopPropagation();
 451       return false;
 452     },
 453     cancelResetArrows: function() {
 454       this.startArrow = null;
 455       this.arrows = [];
 456       this.circles = {};
 457       const curCanvas = document.getElementById("arrowCanvas");
 458       if (!!curCanvas) curCanvas.parentNode.removeChild(curCanvas);
 459     },
 460     coordsToXY: function(coords, top, left, squareWidth) {
 461       return {
 462         // [1] for x and [0] for y because conventions in rules are inversed.
 463         x: (
 464           left + window.scrollX +
 465           (
 466             squareWidth *
 467             (this.orientation == 'w' ? coords[1] : (V.size.y - coords[1]))
 468           )
 469         ),
 470         y: (
 471           top + window.scrollY +
 472           (
 473             squareWidth *
 474             (this.orientation == 'w' ? coords[0] : (V.size.x - coords[0]))
 475           )
 476         )
 477       };
 478     },
 479     computeEndArrow: function(start, end, top, left, squareWidth) {
 480       const endCoords = this.coordsToXY(end, top, left, squareWidth);
 481       const delta = [endCoords.x - start.x, endCoords.y - start.y];
 482       const dist = Math.sqrt(delta[0] * delta[0] + delta[1] * delta[1]);
 483       // Simple heuristic for now, just remove 1/3 square.
 484       // TODO: should depend on the orientation.
 485       const fracSqWidth = squareWidth / 3;
 486       return {
 487         x: endCoords.x - delta[0] * fracSqWidth / dist,
 488         y: endCoords.y - delta[1] * fracSqWidth / dist
 489       };
 490     },
 491     drawCurrentArrow: function() {
 492       const boardElt = document.getElementById("gamePosition");
 493       const squareWidth = boardElt.offsetWidth / V.size.y;
 494       const bPos = boardElt.getBoundingClientRect();
 495       const aStart =
 496         this.coordsToXY(
 497           [this.startArrow[0] + 0.5, this.startArrow[1] + 0.5],
 498           bPos.top, bPos.left, squareWidth);
 499       const aEnd =
 500         this.computeEndArrow(
 501           aStart, [this.movingArrow[0] + 0.5, this.movingArrow[1] + 0.5],
 502           bPos.top, bPos.left, squareWidth);
 503       let currentArrow = document.getElementById("currentArrow");
 504       const d =
 505         "M" + aStart.x + "," + aStart.y + " " + "L" + aEnd.x + "," + aEnd.y;
 506       const arrowWidth = squareWidth / 4;
 507       if (!!currentArrow) currentArrow.setAttribute("d", d);
 508       else {
 509         let domArrow =
 510           document.createElementNS("http://www.w3.org/2000/svg", "path");
 511         domArrow.classList.add("svg-arrow");
 512         domArrow.id = "currentArrow";
 513         domArrow.setAttribute("d", d);
 514         domArrow.style = "stroke-width:" + arrowWidth + "px";
 515         document.getElementById("arrowCanvas")
 516           .insertAdjacentElement("beforeend", domArrow);
 517       }
 518     },
 519     addArrow: function(arrow) {
 520       this.arrows.push(arrow);
 521       // Also add to DOM:
 522       const boardElt = document.getElementById("gamePosition");
 523       const squareWidth = boardElt.offsetWidth / V.size.y;
 524       const bPos = boardElt.getBoundingClientRect();
 525       const newArrow =
 526         this.getSvgArrow(arrow, bPos.top, bPos.left, squareWidth);
 527       document.getElementById("arrowCanvas")
 528         .insertAdjacentElement("beforeend", newArrow);
 529     },
 530     getSvgArrow: function(arrow, top, left, squareWidth) {
 531       const aStart =
 532         this.coordsToXY(
 533           [arrow.start[0] + 0.5, arrow.start[1] + 0.5],
 534           top, left, squareWidth);
 535       const aEnd =
 536         this.computeEndArrow(
 537           aStart, [arrow.end[0] + 0.5, arrow.end[1] + 0.5],
 538           top, left, squareWidth);
 539       const arrowWidth = squareWidth / 4;
 540       let path =
 541         document.createElementNS("http://www.w3.org/2000/svg", "path");
 542       path.classList.add("svg-arrow");
 543       path.setAttribute(
 544         "d",
 545         "M" + aStart.x + "," + aStart.y + " " + "L" + aEnd.x + "," + aEnd.y
 546       );
 547       path.style = "stroke-width:" + arrowWidth + "px";
 548       return path;
 549     },
 550     re_setDrawings: function() {
 551       // Remove current canvas, if any
 552       const curCanvas = document.getElementById("arrowCanvas");
 553       if (!!curCanvas) curCanvas.parentNode.removeChild(curCanvas);
 554       // Add some drawing on board (for some variants + arrows and circles)
 555       const boardElt = document.getElementById("gamePosition");
 556       const squareWidth = boardElt.offsetWidth / V.size.y;
 557       const bPos = boardElt.getBoundingClientRect();
 558       let svgArrows = [];
 559       this.arrows.forEach(a => {
 560         svgArrows.push(this.getSvgArrow(a, bPos.top, bPos.left, squareWidth));
 561       });
 562       let vLines = [];
 563       if (!!V.Lines) {
 564         V.Lines.forEach(line => {
 565           const lStart =
 566             this.coordsToXY(line[0], bPos.top, bPos.left, squareWidth);
 567           const lEnd =
 568             this.coordsToXY(line[1], bPos.top, bPos.left, squareWidth);
 569           let path =
 570             document.createElementNS("http://www.w3.org/2000/svg", "path");
 571           path.classList.add("svg-line");
 572           path.setAttribute(
 573             "d",
 574             "M" + lStart.x + "," + lStart.y + " " +
 575               "L" + lEnd.x + "," + lEnd.y
 576           );
 577           vLines.push(path);
 578         });
 579       }
 580       let arrowCanvas =
 581         document.createElementNS("http://www.w3.org/2000/svg", "svg");
 582       arrowCanvas.id = "arrowCanvas";
 583       arrowCanvas.setAttribute("stroke", "none");
 584       let defs =
 585         document.createElementNS("http://www.w3.org/2000/svg", "defs");
 586       const arrowWidth = squareWidth / 4;
 587       let marker =
 588         document.createElementNS("http://www.w3.org/2000/svg", "marker");
 589       marker.id = "arrow";
 590       marker.setAttribute("markerWidth", (2 * arrowWidth) + "px");
 591       marker.setAttribute("markerHeight", (3 * arrowWidth) + "px");
 592       marker.setAttribute("markerUnits", "userSpaceOnUse");
 593       marker.setAttribute("refX", "0");
 594       marker.setAttribute("refY", (1.5 * arrowWidth) + "px");
 595       marker.setAttribute("orient", "auto");
 596       let head =
 597         document.createElementNS("http://www.w3.org/2000/svg", "path");
 598       head.classList.add("arrow-head");
 599       head.setAttribute(
 600         "d",
 601         "M0,0 L0," + (3 * arrowWidth) + " L" +
 602           (2 * arrowWidth) + "," + (1.5 * arrowWidth) + " z"
 603       );
 604       marker.appendChild(head);
 605       defs.appendChild(marker);
 606       arrowCanvas.appendChild(defs);
 607       svgArrows.concat(vLines).forEach(av => arrowCanvas.appendChild(av));
 608       document.getElementById("rootBoardElement").appendChild(arrowCanvas);
 609     },
 610     mousedown: function(e) {
 611       e.preventDefault();
 612       if (!this.mobileBrowser && e.which != 3)
 613         // Cancel current drawing and circles, if any
 614         this.cancelResetArrows();
 615       if (this.mobileBrowser || e.which == 1) {
 616         // Mouse left button
 617         if (!this.start) {
 618           this.containerPos =
 619             document.getElementById("boardContainer").getBoundingClientRect();
 620           // NOTE: classList[0] is enough: 'piece' is the first assigned class
 621           const withPiece = (e.target.classList[0] == "piece");
 622           // Emit the click event which could be used by some variants
 623           this.$emit(
 624             "click-square",
 625             getSquareFromId(withPiece ? e.target.parentNode.id : e.target.id)
 626           );
 627           // Start square must contain a piece.
 628           if (!withPiece) return;
 629           let parent = e.target.parentNode; //surrounding square
 630           // Show possible moves if current player allowed to play
 631           const startSquare = getSquareFromId(parent.id);
 632           this.possibleMoves = [];
 633           const color = this.analyze ? this.vr.turn : this.userColor;
 634           if (this.vr.canIplay(color, startSquare))
 635             this.possibleMoves = this.vr.getPossibleMovesFrom(startSquare);
 636           // For potential drag'n drop, remember start coordinates
 637           // (to center the piece on mouse cursor)
 638           const rect = parent.getBoundingClientRect();
 639           this.start = {
 640             x: rect.x + rect.width / 2,
 641             y: rect.y + rect.width / 2,
 642             id: parent.id
 643           };
 644           // Add the moving piece to the board, just after current image
 645           this.selectedPiece = e.target.cloneNode();
 646           Object.assign(
 647             this.selectedPiece.style,
 648             {
 649               position: "absolute",
 650               top: 0,
 651               display: "inline-block",
 652               zIndex: 3000
 653             }
 654           );
 655           parent.insertBefore(this.selectedPiece, e.target.nextSibling);
 656         } else {
 657           this.processMoveAttempt(e);
 658         }
 659       } else if (e.which == 3) {
 660         // Mouse right button
 661         this.containerPos =
 662           document.getElementById("gamePosition").getBoundingClientRect();
 663         let elem = e.target;
 664         // Next loop because of potential marks
 665         while (elem.tagName == "IMG") elem = elem.parentNode;
 666         this.startArrow = getSquareFromId(elem.id);
 667       }
 668     },
 669     mousemove: function(e) {
 670       if (!this.selectedPiece && !this.startArrow) return;
 671       // Cancel if off boardContainer
 672       const [offsetX, offsetY] =
 673         this.mobileBrowser
 674           ?
 675             [
 676               e.changedTouches[0].pageX,
 677               // TODO: fixing attempt for smartphones, removing window.scrollY
 678               e.changedTouches[0].pageY - window.scrollY
 679             ]
 680           : [e.clientX, e.clientY];
 681       if (
 682         offsetX < this.containerPos.left ||
 683         offsetX > this.containerPos.right ||
 684         offsetY < this.containerPos.top ||
 685         offsetY > this.containerPos.bottom
 686       ) {
 687         if (!!this.selectedPiece) {
 688           this.selectedPiece.parentNode.removeChild(this.selectedPiece);
 689           delete this.selectedPiece;
 690           this.selectedPiece = null;
 691           this.start = null;
 692           this.possibleMoves = []; //in case of
 693           this.click = "";
 694           let selected = document.querySelector(".ghost");
 695           if (!!selected) selected.classList.remove("ghost");
 696         }
 697         else {
 698           this.startArrow = null;
 699           this.movingArrow = null;
 700           const currentArrow = document.getElementById("currentArrow");
 701           if (!!currentArrow)
 702             currentArrow.parentNode.removeChild(currentArrow);
 703         }
 704         return;
 705       }
 706       e.preventDefault();
 707       if (!!this.selectedPiece) {
 708         // There is an active element: move it around
 709         Object.assign(
 710           this.selectedPiece.style,
 711           {
 712             left: offsetX - this.start.x + "px",
 713             top: offsetY - this.start.y + "px"
 714           }
 715         );
 716       }
 717       else {
 718         let elem = e.target;
 719         // Next loop because of potential marks
 720         while (elem.tagName == "IMG") elem = elem.parentNode;
 721         // To center the arrow in square:
 722         const movingCoords = getSquareFromId(elem.id);
 723         if (
 724           movingCoords[0] != this.startArrow[0] ||
 725           movingCoords[1] != this.startArrow[1]
 726         ) {
 727           this.movingArrow = movingCoords;
 728           this.drawCurrentArrow();
 729         }
 730       }
 731     },
 732     mouseup: function(e) {
 733       e.preventDefault();
 734       if (this.mobileBrowser || e.which == 1) {
 735         if (!this.selectedPiece) return;
 736         // Drag'n drop. Selected piece is no longer needed:
 737         this.selectedPiece.parentNode.removeChild(this.selectedPiece);
 738         delete this.selectedPiece;
 739         this.selectedPiece = null;
 740         this.processMoveAttempt(e);
 741       } else if (e.which == 3) {
 742         if (!this.startArrow) return;
 743         // Mouse right button
 744         this.movingArrow = null;
 745         this.processArrowAttempt(e);
 746       }
 747     },
 748     // Called by BaseGame after partially undoing multi-moves:
 749     resetCurrentAttempt: function() {
 750       this.possibleMoves = [];
 751       this.start = null;
 752       this.click = "";
 753       this.selectedPiece = null;
 754     },
 755     processMoveAttempt: function(e) {
 756       // Obtain the move from start and end squares
 757       const [offsetX, offsetY] =
 758         this.mobileBrowser
 759           ?
 760             [
 761               e.changedTouches[0].pageX,
 762               e.changedTouches[0].pageY - window.scrollY
 763             ]
 764           : [e.clientX, e.clientY];
 765       let landing = document.elementFromPoint(offsetX, offsetY);
 766       // Next condition: classList.contains(piece) fails because of marks
 767       while (landing.tagName == "IMG") landing = landing.parentNode;
 768       if (this.start.id == landing.id) {
 769         if (this.click == landing.id) {
 770           // Second click on same square: cancel current move
 771           this.possibleMoves = [];
 772           this.start = null;
 773           this.click = "";
 774         } else this.click = landing.id;
 775         return;
 776       }
 777       this.start = null;
 778       // OK: process move attempt, landing is a square node
 779       let endSquare = getSquareFromId(landing.id);
 780       let moves = this.findMatchingMoves(endSquare);
 781       this.possibleMoves = [];
 782       if (moves.length > 1) {
 783         this.clickTime = Date.now();
 784         this.choices = moves;
 785       } else if (moves.length == 1) this.play(moves[0]);
 786       // else: forbidden move attempt
 787     },
 788     processArrowAttempt: function(e) {
 789       // Obtain the arrow from start and end squares
 790       const [offsetX, offsetY] = [e.clientX, e.clientY];
 791       let landing = document.elementFromPoint(offsetX, offsetY);
 792       // Next condition: classList.contains(piece) fails because of marks
 793       while (landing.tagName == "IMG") landing = landing.parentNode;
 794       const landingCoords = getSquareFromId(landing.id);
 795       if (
 796         this.startArrow[0] == landingCoords[0] &&
 797         this.startArrow[1] == landingCoords[1]
 798       ) {
 799         // Draw (or erase) a circle
 800         this.$set(this.circles, landing.id, !this.circles[landing.id]);
 801       }
 802       else {
 803         // OK: add arrow, landing is a new square
 804         const currentArrow = document.getElementById("currentArrow");
 805         currentArrow.parentNode.removeChild(currentArrow);
 806         this.addArrow({
 807           start: this.startArrow,
 808           end: landingCoords
 809         });
 810       }
 811       this.startArrow = null;
 812     },
 813     findMatchingMoves: function(endSquare) {
 814       // Run through moves list and return the matching set (if promotions...)
 815       return (
 816         this.possibleMoves.filter(m => {
 817           return (endSquare[0] == m.end.x && endSquare[1] == m.end.y);
 818         })
 819       );
 820     },
 821     play: function(move) {
 822       this.$emit("play-move", move);
 823     }
 824   }
 825 };
 826 </script>
 827
 828 <style lang="sass">
 829 // SVG dynamically added, so not scoped
 830 #arrowCanvas
 831   pointer-events: none
 832   position: absolute
 833   top: 0
 834   left: 0
 835   width: 100%
 836   height: 100%
 837
 838 .svg-arrow
 839   opacity: 0.65
 840   stroke: #5f0e78
 841   fill: none
 842   marker-end: url(#arrow)
 843
 844 .svg-line
 845   stroke: black
 846
 847 .arrow-head
 848   fill: #5f0e78
 849 </style>
 850
 851 <style lang="sass" scoped>
 852 @import "@/styles/_board_squares_img.sass";
 853
 854 //.game.reserve-div
 855   // TODO: would be cleaner to restrict width so that it doesn't overflow
 856   // Commented out because pieces would disappear over the board otherwise:
 857   //overflow: hidden
 858 .reserve-count
 859   width: 100%
 860   text-align: center
 861   display: inline-block
 862   position: absolute
 863 .reserve-row
 864   margin-bottom: 15px
 865
 866 .full-width
 867   width: 100%
 868
 869 .game
 870   user-select: none
 871   width: 100%
 872   margin: 0
 873   .board
 874     cursor: pointer
 875
 876 #choices
 877   user-select: none
 878   margin: 0
 879   position: absolute
 880   z-index: 300
 881   overflow-y: inherit
 882   background-color: rgba(0,0,0,0)
 883   img
 884     cursor: pointer
 885     background-color: #e6ee9c
 886     &:hover
 887       background-color: skyblue
 888     &.choice-piece
 889       width: 100%
 890       height: auto
 891       display: block
 892
 893 img.ghost
 894   // NOTE: no need to set z-index here, since opacity is low
 895   position: absolute
 896   opacity: 0.5
 897   top: 0
 898
 899 .incheck-light
 900   background-color: rgba(204, 51, 0, 0.7) !important
 901 .incheck-dark
 902   background-color: rgba(204, 51, 0, 0.9) !important
 903
 904 .light-square.lichess
 905   background-color: #f0d9b5
 906 .dark-square.lichess
 907   background-color: #b58863
 908
 909 .light-square.chesscom
 910   background-color: #e5e5ca
 911 .dark-square.chesscom
 912   background-color: #6f8f57
 913
 914 .light-square.chesstempo
 915   background-color: #dfdfdf
 916 .dark-square.chesstempo
 917   background-color: #7287b6
 918
 919 .middle-square.lichess
 920   background-color: #D3B18C
 921
 922 .middle-square.chesscom
 923   background-color: #AABA91
 924
 925 .middle-square.chesstempo
 926   background-color: #A9B3CB
 927
 928 // TODO: no predefined highlight colors, but layers. How?
 929
 930 .light-square.lichess.highlight-light
 931   background-color: #cdd26a
 932 .dark-square.lichess.highlight-dark
 933   background-color: #aaa23a
 934
 935 .light-square.chesscom.highlight-light
 936   background-color: #f7f783
 937 .dark-square.chesscom.highlight-dark
 938   background-color: #bacb44
 939
 940 .light-square.chesstempo.highlight-light
 941   background-color: #9f9fff
 942 .dark-square.chesstempo.highlight-dark
 943   background-color: #557fff
 944 </style>