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 (!m.start.noHighlight && V.OnBoard(m.start.x, m.start.y))
  64           lmHighlights[m.start.x + sizeX * m.start.y] = true;
  65         if (!m.end.noHighlight && V.OnBoard(m.end.x, m.end.y))
  66           lmHighlights[m.end.x + sizeX * m.end.y] = true;
  67         if (!!m.start.toplay)
  68           // For Dice variant (at least?)
  69           lmHighlights[m.start.toplay[0] + sizeX * m.start.toplay[1]] = true;
  70       });
  71     }
  72     const showLight = (
  73       this.settings.highlight &&
  74       ["all", "highlight"].includes(V.ShowMoves)
  75     );
  76     const showCheck = (
  77       this.settings.highlight &&
  78       ["all", "highlight", "byrow"].includes(V.ShowMoves)
  79     );
  80     const orientation = !V.CanFlip ? "w" : this.orientation;
  81     // Ensure that squares colors do not change when board is flipped
  82     const lightSquareMod = (sizeX + sizeY) % 2;
  83     const showPiece = (x, y) => {
  84       return (
  85         this.vr.board[x][y] != V.EMPTY &&
  86         (!this.vr.enlightened || this.analyze || this.score != "*" ||
  87           (!!this.userColor && this.vr.enlightened[this.userColor][x][y]))
  88       );
  89     };
  90     const inHighlight = (x, y) => {
  91       return showLight && !!lmHighlights[x + sizeX * y];
  92     };
  93     const inShadow = (x, y) => {
  94       return (
  95         !this.analyze &&
  96         this.score == "*" &&
  97         this.vr.enlightened &&
  98         (!this.userColor || !this.vr.enlightened[this.userColor][x][y])
  99       );
 100     };
 101     // Create board element (+ reserves if needed by variant)
 102     let elementArray = [];
 103     const gameDiv = h(
 104       "div",
 105       {
 106         attrs: { id: "gamePosition" },
 107         "class": {
 108           game: true,
 109           clearer: true
 110         }
 111       },
 112       [...Array(sizeX).keys()].map(i => {
 113         const ci = orientation == "w" ? i : sizeX - i - 1;
 114         return h(
 115           "div",
 116           {
 117             "class": {
 118               row: true
 119             },
 120             style: { opacity: this.choices.length > 0 ? "0.5" : "1" }
 121           },
 122           [...Array(sizeY).keys()].map(j => {
 123             const cj = orientation == "w" ? j : sizeY - j - 1;
 124             const squareId = "sq-" + ci + "-" + cj;
 125             let elems = [];
 126             if (showPiece(ci, cj)) {
 127               let pieceSpecs = {
 128                 "class": {
 129                   piece: true,
 130                   ghost:
 131                     !!this.selectedPiece &&
 132                     this.selectedPiece.parentNode.id == squareId
 133                 },
 134                 attrs: {
 135                   src:
 136                     "/images/pieces/" +
 137                     this.vr.getPpath(
 138                       this.vr.board[ci][cj],
 139                       // Extra args useful for some variants:
 140                       this.userColor,
 141                       this.score,
 142                       this.orientation) +
 143                     V.IMAGE_EXTENSION
 144                 }
 145               };
 146               if (this.arrows.length == 0)
 147                 pieceSpecs["style"] = { position: "absolute" };
 148               elems.push(h("img", pieceSpecs));
 149             }
 150             if (this.settings.hints && hintSquares[ci][cj]) {
 151               elems.push(
 152                 h("img", {
 153                   "class": {
 154                     "mark-square": true
 155                   },
 156                   attrs: {
 157                     src: "/images/mark.svg"
 158                   }
 159                 })
 160               );
 161             }
 162             if (!!this.circles[squareId]) {
 163               elems.push(
 164                 h("img", {
 165                   "class": {
 166                     "circle-square": true
 167                   },
 168                   attrs: {
 169                     src: "/images/circle.svg"
 170                   }
 171                 })
 172               );
 173             }
 174             const oddity = (ci + cj) % 2;
 175             const lightSquare = (
 176               (!V.DarkBottomRight && oddity == lightSquareMod) ||
 177               (V.DarkBottomRight && oddity != lightSquareMod)
 178             );
 179             return h(
 180               "div",
 181               {
 182                 "class": {
 183                   board: true,
 184                   ["board" + sizeY]: true,
 185                   "light-square":
 186                     !V.Notoodark && lightSquare && !V.Monochrome,
 187                   "dark-square":
 188                     !V.Notoodark && (!lightSquare || !!V.Monochrome),
 189                   "middle-square": V.Notoodark,
 190                   [this.settings.bcolor]: true,
 191                   "in-shadow": inShadow(ci, cj),
 192                   "highlight": inHighlight(ci, cj),
 193                   "incheck-light":
 194                     showCheck && lightSquare && incheckSq[ci][cj],
 195                   "incheck-dark":
 196                     showCheck && !lightSquare && incheckSq[ci][cj],
 197                   "hover-highlight": this.vr.hoverHighlight(ci, cj)
 198                 },
 199                 attrs: {
 200                   id: getSquareId({ x: ci, y: cj })
 201                 }
 202               },
 203               elems
 204             );
 205           })
 206         );
 207       })
 208     );
 209     if (!!this.vr.reserve) {
 210       const playingColor = this.userColor || "w"; //default for an observer
 211       const shiftIdx = playingColor == "w" ? 0 : 1;
 212       // Some variants have more than sizeY reserve pieces (Clorange: 10)
 213       const reserveSquareNb = Math.max(sizeY, V.RESERVE_PIECES.length);
 214       let myReservePiecesArray = [];
 215       if (!!this.vr.reserve[playingColor]) {
 216         for (let i = 0; i < V.RESERVE_PIECES.length; i++) {
 217           const qty = this.vr.reserve[playingColor][V.RESERVE_PIECES[i]];
 218           myReservePiecesArray.push(
 219             h(
 220               "div",
 221               {
 222                 "class": { board: true, ["board" + reserveSquareNb]: true },
 223                 attrs: { id: getSquareId({ x: sizeX + shiftIdx, y: i }) },
 224                 style: { opacity: qty > 0 ? 1 : 0.35 }
 225               },
 226               [
 227                 h("img", {
 228                   // NOTE: class "reserve" not used currently
 229                   "class": { piece: true, reserve: true },
 230                   attrs: {
 231                     src:
 232                       "/images/pieces/" +
 233                       this.vr.getReservePpath(i, playingColor, orientation) +
 234                       ".svg"
 235                   }
 236                 }),
 237                 h(
 238                   "sup",
 239                   {
 240                     "class": { "reserve-count": true },
 241                     style: { top: "calc(100% + 5px)" }
 242                   },
 243                   [ qty ]
 244                 )
 245               ]
 246             )
 247           );
 248         }
 249       }
 250       let oppReservePiecesArray = [];
 251       const oppCol = V.GetOppCol(playingColor);
 252       if (!!this.vr.reserve[oppCol]) {
 253         for (let i = 0; i < V.RESERVE_PIECES.length; i++) {
 254           const qty = this.vr.reserve[oppCol][V.RESERVE_PIECES[i]];
 255           oppReservePiecesArray.push(
 256             h(
 257               "div",
 258               {
 259                 "class": { board: true, ["board" + reserveSquareNb]: true },
 260                 attrs: { id: getSquareId({ x: sizeX + (1 - shiftIdx), y: i }) },
 261                 style: { opacity: qty > 0 ? 1 : 0.35 }
 262               },
 263               [
 264                 h("img", {
 265                   "class": { piece: true, reserve: true },
 266                   attrs: {
 267                     src:
 268                       "/images/pieces/" +
 269                       this.vr.getReservePpath(i, oppCol, orientation) +
 270                       ".svg"
 271                   }
 272                 }),
 273                 h(
 274                   "sup",
 275                   {
 276                     "class": { "reserve-count": true },
 277                     style: { top: "calc(100% + 5px)" }
 278                   },
 279                   [ qty ]
 280                 )
 281               ]
 282             )
 283           );
 284         }
 285       }
 286       const myReserveTop = (
 287         (playingColor == 'w' && orientation == 'b') ||
 288         (playingColor == 'b' && orientation == 'w')
 289       );
 290       const hasReserveTop = (
 291         (myReserveTop && !!this.vr.reserve[playingColor]) ||
 292         (!myReserveTop && !!this.vr.reserve[oppCol])
 293       );
 294       // "var" because must be reachable from outside this block
 295       var hasReserveBottom = (
 296         (myReserveTop && !!this.vr.reserve[oppCol]) ||
 297         (!myReserveTop && !!this.vr.reserve[playingColor])
 298       );
 299       // Center reserves, assuming same number of pieces for each side:
 300       const nbReservePieces = myReservePiecesArray.length;
 301       const marginLeft =
 302         ((100 - nbReservePieces * (100 / reserveSquareNb)) / 2) + "%";
 303       if (hasReserveTop) {
 304         var reserveTop =
 305           h(
 306             "div",
 307             {
 308               "class": {
 309                 game: true,
 310                 "reserve-div": true
 311               },
 312               style: {
 313                 "margin-left": marginLeft
 314               }
 315             },
 316             [
 317               h(
 318                 "div",
 319                 {
 320                   "class": {
 321                     row: true,
 322                     "reserve-row": true
 323                   }
 324                 },
 325                 myReserveTop ? myReservePiecesArray : oppReservePiecesArray
 326               )
 327             ]
 328           );
 329       }
 330       if (hasReserveBottom) {
 331         var reserveBottom =
 332           h(
 333             "div",
 334             {
 335               "class": {
 336                 game: true,
 337                 "reserve-div": true
 338               },
 339               style: {
 340                 "margin-left": marginLeft
 341               }
 342             },
 343             [
 344               h(
 345                 "div",
 346                 {
 347                   "class": {
 348                     row: true,
 349                     "reserve-row": true
 350                   }
 351                 },
 352                 myReserveTop ? oppReservePiecesArray : myReservePiecesArray
 353               )
 354             ]
 355           );
 356       }
 357       if (hasReserveTop) elementArray.push(reserveTop);
 358     }
 359     elementArray.push(gameDiv);
 360     if (!!this.vr.reserve && hasReserveBottom)
 361       elementArray.push(reserveBottom);
 362     const boardElt = document.getElementById("gamePosition");
 363     // boardElt might be undefine (at first drawing)
 364     if (this.choices.length > 0 && !!boardElt) {
 365       const squareWidth = boardElt.offsetWidth / sizeY;
 366       const offset = [boardElt.offsetTop, boardElt.offsetLeft];
 367       const maxNbeltsPerRow = Math.min(this.choices.length, sizeY);
 368       let topOffset = offset[0] + (sizeY / 2) * squareWidth - squareWidth / 2;
 369       let choicesHeight = squareWidth;
 370       if (this.choices.length >= sizeY) {
 371         // A second row is required (Eightpieces variant)
 372         topOffset -= squareWidth / 2;
 373         choicesHeight *= 2;
 374       }
 375       const choices = h(
 376         "div",
 377         {
 378           attrs: { id: "choices" },
 379           "class": { row: true },
 380           style: {
 381             top: topOffset + "px",
 382             left:
 383               offset[1] +
 384               (squareWidth * Math.max(sizeY - this.choices.length, 0)) / 2 +
 385               "px",
 386             width: (maxNbeltsPerRow * squareWidth) + "px",
 387             height: choicesHeight + "px"
 388           }
 389         },
 390         [ h(
 391           "div",
 392           {
 393             "class": { "full-width": true }
 394           },
 395           this.choices.map(m => {
 396             // A "choice" is a move
 397             const applyMove = (e) => {
 398               e.stopPropagation();
 399               // Force a delay between move is shown and clicked
 400               // (otherwise a "double-click" bug might occur)
 401               if (Date.now() - this.clickTime < 200) return;
 402               this.choices = [];
 403               this.play(m);
 404             };
 405             const onClick =
 406               this.mobileBrowser
 407                 ? { touchend: applyMove }
 408                 : { mouseup: applyMove };
 409             return h(
 410               "div",
 411               {
 412                 "class": {
 413                   board: true,
 414                   ["board" + sizeY]: true
 415                 },
 416                 style: {
 417                   width: (100 / maxNbeltsPerRow) + "%",
 418                   "padding-bottom": (100 / maxNbeltsPerRow) + "%"
 419                 }
 420               },
 421               [
 422                 h("img", {
 423                   attrs: {
 424                     src:
 425                       "/images/pieces/" +
 426                       // orientation: extra arg useful for some variants:
 427                       this.vr.getPPpath(m, this.orientation) +
 428                       V.IMAGE_EXTENSION
 429                   },
 430                   "class": { "choice-piece": true },
 431                   on: onClick
 432                 })
 433               ]
 434             );
 435           })
 436         ) ]
 437       );
 438       elementArray.unshift(choices);
 439     }
 440     let onEvents = {};
 441     // NOTE: click = mousedown + mouseup
 442     if (this.mobileBrowser) {
 443       onEvents = {
 444         on: {
 445           touchstart: this.mousedown,
 446           touchmove: this.mousemove,
 447           touchend: this.mouseup
 448         }
 449       };
 450     }
 451     else {
 452       onEvents = {
 453         on: {
 454           mousedown: this.mousedown,
 455           mousemove: this.mousemove,
 456           mouseup: this.mouseup,
 457           contextmenu: this.blockContextMenu
 458         }
 459       };
 460     }
 461     return (
 462       h(
 463         "div",
 464         Object.assign({ attrs: { id: "rootBoardElement" } }, onEvents),
 465         elementArray
 466       )
 467     );
 468   },
 469   updated: function() {
 470     this.re_setDrawings();
 471   },
 472   methods: {
 473     blockContextMenu: function(e) {
 474       e.preventDefault();
 475       e.stopPropagation();
 476       return false;
 477     },
 478     cancelResetArrows: function() {
 479       this.startArrow = null;
 480       this.arrows = [];
 481       this.circles = {};
 482       const curCanvas = document.getElementById("arrowCanvas");
 483       if (!!curCanvas) curCanvas.parentNode.removeChild(curCanvas);
 484     },
 485     coordsToXY: function(coords, top, left, squareWidth) {
 486       return {
 487         // [1] for x and [0] for y because conventions in rules are inversed.
 488         x: (
 489           left + window.scrollX +
 490           (
 491             squareWidth *
 492             (this.orientation == 'w' ? coords[1] : (V.size.y - coords[1]))
 493           )
 494         ),
 495         y: (
 496           top + window.scrollY +
 497           (
 498             squareWidth *
 499             (this.orientation == 'w' ? coords[0] : (V.size.x - coords[0]))
 500           )
 501         )
 502       };
 503     },
 504     computeEndArrow: function(start, end, top, left, squareWidth) {
 505       const endCoords = this.coordsToXY(end, top, left, squareWidth);
 506       const delta = [endCoords.x - start.x, endCoords.y - start.y];
 507       const dist = Math.sqrt(delta[0] * delta[0] + delta[1] * delta[1]);
 508       // Simple heuristic for now, just remove 1/3 square.
 509       // TODO: should depend on the orientation.
 510       const fracSqWidth = squareWidth / 3;
 511       return {
 512         x: endCoords.x - delta[0] * fracSqWidth / dist,
 513         y: endCoords.y - delta[1] * fracSqWidth / dist
 514       };
 515     },
 516     drawCurrentArrow: function() {
 517       const boardElt = document.getElementById("gamePosition");
 518       const squareWidth = boardElt.offsetWidth / V.size.y;
 519       const bPos = boardElt.getBoundingClientRect();
 520       const aStart =
 521         this.coordsToXY(
 522           [this.startArrow[0] + 0.5, this.startArrow[1] + 0.5],
 523           bPos.top, bPos.left, squareWidth);
 524       const aEnd =
 525         this.computeEndArrow(
 526           aStart, [this.movingArrow[0] + 0.5, this.movingArrow[1] + 0.5],
 527           bPos.top, bPos.left, squareWidth);
 528       let currentArrow = document.getElementById("currentArrow");
 529       const d =
 530         "M" + aStart.x + "," + aStart.y + " " + "L" + aEnd.x + "," + aEnd.y;
 531       const arrowWidth = squareWidth / 4;
 532       if (!!currentArrow) currentArrow.setAttribute("d", d);
 533       else {
 534         let domArrow =
 535           document.createElementNS("http://www.w3.org/2000/svg", "path");
 536         domArrow.classList.add("svg-arrow");
 537         domArrow.id = "currentArrow";
 538         domArrow.setAttribute("d", d);
 539         domArrow.style = "stroke-width:" + arrowWidth + "px";
 540         document.getElementById("arrowCanvas")
 541           .insertAdjacentElement("beforeend", domArrow);
 542       }
 543     },
 544     addArrow: function(arrow) {
 545       this.arrows.push(arrow);
 546       // Also add to DOM:
 547       const boardElt = document.getElementById("gamePosition");
 548       const squareWidth = boardElt.offsetWidth / V.size.y;
 549       const bPos = boardElt.getBoundingClientRect();
 550       const newArrow =
 551         this.getSvgArrow(arrow, bPos.top, bPos.left, squareWidth);
 552       document.getElementById("arrowCanvas")
 553         .insertAdjacentElement("beforeend", newArrow);
 554     },
 555     getSvgArrow: function(arrow, top, left, squareWidth) {
 556       const aStart =
 557         this.coordsToXY(
 558           [arrow.start[0] + 0.5, arrow.start[1] + 0.5],
 559           top, left, squareWidth);
 560       const aEnd =
 561         this.computeEndArrow(
 562           aStart, [arrow.end[0] + 0.5, arrow.end[1] + 0.5],
 563           top, left, squareWidth);
 564       const arrowWidth = squareWidth / 4;
 565       let path =
 566         document.createElementNS("http://www.w3.org/2000/svg", "path");
 567       path.classList.add("svg-arrow");
 568       path.setAttribute(
 569         "d",
 570         "M" + aStart.x + "," + aStart.y + " " + "L" + aEnd.x + "," + aEnd.y
 571       );
 572       path.style = "stroke-width:" + arrowWidth + "px";
 573       return path;
 574     },
 575     re_setDrawings: function() {
 576       // Remove current canvas, if any
 577       const curCanvas = document.getElementById("arrowCanvas");
 578       if (!!curCanvas) curCanvas.parentNode.removeChild(curCanvas);
 579       // Add some drawing on board (for some variants + arrows and circles)
 580       const boardElt = document.getElementById("gamePosition");
 581       const squareWidth = boardElt.offsetWidth / V.size.y;
 582       const bPos = boardElt.getBoundingClientRect();
 583       let svgArrows = [];
 584       this.arrows.forEach(a => {
 585         svgArrows.push(this.getSvgArrow(a, bPos.top, bPos.left, squareWidth));
 586       });
 587       let vLines = [];
 588       if (!!V.Lines) {
 589         V.Lines.forEach(line => {
 590           const lStart =
 591             this.coordsToXY(line[0], bPos.top, bPos.left, squareWidth);
 592           const lEnd =
 593             this.coordsToXY(line[1], bPos.top, bPos.left, squareWidth);
 594           let path =
 595             document.createElementNS("http://www.w3.org/2000/svg", "path");
 596           if (line[0][0] == line[1][0] || line[0][1] == line[1][1])
 597             path.classList.add("svg-line");
 598           else
 599             // "Diagonals" are drawn with a lighter color (TODO: generalize)
 600             path.classList.add("svg-diag");
 601           path.setAttribute(
 602             "d",
 603             "M" + lStart.x + "," + lStart.y + " " +
 604               "L" + lEnd.x + "," + lEnd.y
 605           );
 606           vLines.push(path);
 607         });
 608       }
 609       let arrowCanvas =
 610         document.createElementNS("http://www.w3.org/2000/svg", "svg");
 611       arrowCanvas.id = "arrowCanvas";
 612       arrowCanvas.setAttribute("stroke", "none");
 613       let defs =
 614         document.createElementNS("http://www.w3.org/2000/svg", "defs");
 615       const arrowWidth = squareWidth / 4;
 616       let marker =
 617         document.createElementNS("http://www.w3.org/2000/svg", "marker");
 618       marker.id = "arrow";
 619       marker.setAttribute("markerWidth", (2 * arrowWidth) + "px");
 620       marker.setAttribute("markerHeight", (3 * arrowWidth) + "px");
 621       marker.setAttribute("markerUnits", "userSpaceOnUse");
 622       marker.setAttribute("refX", "0");
 623       marker.setAttribute("refY", (1.5 * arrowWidth) + "px");
 624       marker.setAttribute("orient", "auto");
 625       let head =
 626         document.createElementNS("http://www.w3.org/2000/svg", "path");
 627       head.classList.add("arrow-head");
 628       head.setAttribute(
 629         "d",
 630         "M0,0 L0," + (3 * arrowWidth) + " L" +
 631           (2 * arrowWidth) + "," + (1.5 * arrowWidth) + " z"
 632       );
 633       marker.appendChild(head);
 634       defs.appendChild(marker);
 635       arrowCanvas.appendChild(defs);
 636       svgArrows.concat(vLines).forEach(av => arrowCanvas.appendChild(av));
 637       document.getElementById("rootBoardElement").appendChild(arrowCanvas);
 638     },
 639     mousedown: function(e) {
 640       e.preventDefault();
 641       if (!this.mobileBrowser && e.which != 3)
 642         // Cancel current drawing and circles, if any
 643         this.cancelResetArrows();
 644       if (this.mobileBrowser || e.which == 1) {
 645         // Mouse left button
 646         if (!this.start) {
 647           this.containerPos =
 648             document.getElementById("boardContainer").getBoundingClientRect();
 649           // NOTE: classList[0] is enough: 'piece' is the first assigned class
 650           const withPiece = (e.target.classList[0] == "piece");
 651           // Show possible moves if current player allowed to play
 652           const startSquare =
 653             getSquareFromId(withPiece ? e.target.parentNode.id : e.target.id);
 654           this.possibleMoves = [];
 655           const color = this.analyze ? this.vr.turn : this.userColor;
 656           if (this.vr.canIplay(color, startSquare)) {
 657             // Emit the click event which could be used by some variants
 658             const targetId =
 659               (withPiece ? e.target.parentNode.id : e.target.id);
 660             this.$emit("click-square", getSquareFromId(targetId));
 661             if (withPiece) {
 662               this.possibleMoves = this.vr.getPossibleMovesFrom(startSquare);
 663               // For potential drag'n drop, remember start coordinates
 664               // (to center the piece on mouse cursor)
 665               let parent = e.target.parentNode; //surrounding square
 666               const rect = parent.getBoundingClientRect();
 667               this.start = {
 668                 x: rect.x + rect.width / 2,
 669                 y: rect.y + rect.width / 2,
 670                 id: parent.id
 671               };
 672               // Add the moving piece to the board, just after current image
 673               this.selectedPiece = e.target.cloneNode();
 674               Object.assign(
 675                 this.selectedPiece.style,
 676                 {
 677                   position: "absolute",
 678                   top: 0,
 679                   display: "inline-block",
 680                   zIndex: 3000
 681                 }
 682               );
 683               parent.insertBefore(this.selectedPiece, e.target.nextSibling);
 684             }
 685           }
 686         }
 687         else this.processMoveAttempt(e);
 688       }
 689       else if (e.which == 3) {
 690         // Mouse right button
 691         this.containerPos =
 692           document.getElementById("gamePosition").getBoundingClientRect();
 693         let elem = e.target;
 694         // Next loop because of potential marks
 695         while (elem.tagName == "IMG") elem = elem.parentNode;
 696         this.startArrow = getSquareFromId(elem.id);
 697       }
 698     },
 699     mousemove: function(e) {
 700       if (!this.selectedPiece && !this.startArrow) return;
 701       // Cancel if off boardContainer
 702       const [offsetX, offsetY] =
 703         this.mobileBrowser
 704           ? [e.changedTouches[0].clientX, e.changedTouches[0].clientY]
 705           : [e.clientX, e.clientY];
 706       if (
 707         offsetX < this.containerPos.left ||
 708         offsetX > this.containerPos.right ||
 709         offsetY < this.containerPos.top ||
 710         offsetY > this.containerPos.bottom
 711       ) {
 712         if (!!this.selectedPiece) {
 713           this.selectedPiece.parentNode.removeChild(this.selectedPiece);
 714           delete this.selectedPiece;
 715           this.selectedPiece = null;
 716           this.start = null;
 717           this.possibleMoves = []; //in case of
 718           this.click = "";
 719           let selected = document.querySelector(".ghost");
 720           if (!!selected) selected.classList.remove("ghost");
 721         }
 722         else {
 723           this.startArrow = null;
 724           this.movingArrow = null;
 725           const currentArrow = document.getElementById("currentArrow");
 726           if (!!currentArrow)
 727             currentArrow.parentNode.removeChild(currentArrow);
 728         }
 729         return;
 730       }
 731       e.preventDefault();
 732       if (!!this.selectedPiece) {
 733         // There is an active element: move it around
 734         Object.assign(
 735           this.selectedPiece.style,
 736           {
 737             left: offsetX - this.start.x + "px",
 738             top: offsetY - this.start.y + "px"
 739           }
 740         );
 741       }
 742       else {
 743         let elem = e.target;
 744         // Next loop because of potential marks
 745         while (elem.tagName == "IMG") elem = elem.parentNode;
 746         // To center the arrow in square:
 747         const movingCoords = getSquareFromId(elem.id);
 748         if (
 749           movingCoords[0] != this.startArrow[0] ||
 750           movingCoords[1] != this.startArrow[1]
 751         ) {
 752           this.movingArrow = movingCoords;
 753           this.drawCurrentArrow();
 754         }
 755       }
 756     },
 757     mouseup: function(e) {
 758       e.preventDefault();
 759       if (this.mobileBrowser || e.which == 1) {
 760         if (!this.selectedPiece) return;
 761         // Drag'n drop. Selected piece is no longer needed:
 762         this.selectedPiece.parentNode.removeChild(this.selectedPiece);
 763         delete this.selectedPiece;
 764         this.selectedPiece = null;
 765         this.processMoveAttempt(e);
 766       } else if (e.which == 3) {
 767         if (!this.startArrow) return;
 768         // Mouse right button
 769         this.movingArrow = null;
 770         this.processArrowAttempt(e);
 771       }
 772     },
 773     // Called by BaseGame after partially undoing multi-moves:
 774     resetCurrentAttempt: function() {
 775       this.possibleMoves = [];
 776       this.start = null;
 777       this.click = "";
 778       this.selectedPiece = null;
 779     },
 780     processMoveAttempt: function(e) {
 781       // Obtain the move from start and end squares
 782       const [offsetX, offsetY] =
 783         this.mobileBrowser
 784           ? [e.changedTouches[0].clientX, e.changedTouches[0].clientY]
 785           : [e.clientX, e.clientY];
 786       let landing = document.elementFromPoint(offsetX, offsetY);
 787       // Next condition: classList.contains(piece) fails because of marks
 788       while (landing.tagName == "IMG") landing = landing.parentNode;
 789       if (this.start.id == landing.id) {
 790         if (this.click == landing.id) {
 791           // Second click on same square: cancel current move
 792           this.possibleMoves = [];
 793           this.start = null;
 794           this.click = "";
 795         } else this.click = landing.id;
 796         return;
 797       }
 798       this.start = null;
 799       // OK: process move attempt, landing is a square node
 800       let endSquare = getSquareFromId(landing.id);
 801       let moves = this.findMatchingMoves(endSquare);
 802       this.possibleMoves = [];
 803       if (moves.length > 1) {
 804         this.clickTime = Date.now();
 805         this.choices = moves;
 806       } else if (moves.length == 1) this.play(moves[0]);
 807       // else: forbidden move attempt
 808     },
 809     processArrowAttempt: function(e) {
 810       // Obtain the arrow from start and end squares
 811       const [offsetX, offsetY] = [e.clientX, e.clientY];
 812       let landing = document.elementFromPoint(offsetX, offsetY);
 813       // Next condition: classList.contains(piece) fails because of marks
 814       while (landing.tagName == "IMG") landing = landing.parentNode;
 815       const landingCoords = getSquareFromId(landing.id);
 816       if (
 817         this.startArrow[0] == landingCoords[0] &&
 818         this.startArrow[1] == landingCoords[1]
 819       ) {
 820         // Draw (or erase) a circle
 821         this.$set(this.circles, landing.id, !this.circles[landing.id]);
 822       }
 823       else {
 824         // OK: add arrow, landing is a new square
 825         const currentArrow = document.getElementById("currentArrow");
 826         currentArrow.parentNode.removeChild(currentArrow);
 827         this.addArrow({
 828           start: this.startArrow,
 829           end: landingCoords
 830         });
 831       }
 832       this.startArrow = null;
 833     },
 834     findMatchingMoves: function(endSquare) {
 835       // Run through moves list and return the matching set (if promotions...)
 836       return (
 837         this.possibleMoves.filter(m => {
 838           return (endSquare[0] == m.end.x && endSquare[1] == m.end.y);
 839         })
 840       );
 841     },
 842     play: function(move) {
 843       this.$emit("play-move", move);
 844     }
 845   }
 846 };
 847 </script>
 848
 849 <style lang="sass">
 850 // SVG dynamically added, so not scoped
 851 #arrowCanvas
 852   pointer-events: none
 853   position: absolute
 854   top: 0
 855   left: 0
 856   width: 100%
 857   height: 100%
 858
 859 .svg-arrow
 860   opacity: 0.65
 861   stroke: #5f0e78
 862   fill: none
 863   marker-end: url(#arrow)
 864
 865 .svg-line
 866   stroke: black
 867
 868 .svg-diag
 869   stroke: grey
 870
 871 .arrow-head
 872   fill: #5f0e78
 873 </style>
 874
 875 <style lang="sass" scoped>
 876 @import "@/styles/_board_squares_img.sass";
 877
 878 //.game.reserve-div
 879   // TODO: would be cleaner to restrict width so that it doesn't overflow
 880   // Commented out because pieces would disappear over the board otherwise:
 881   //overflow: hidden
 882 .reserve-count
 883   width: 100%
 884   text-align: center
 885   display: inline-block
 886   position: absolute
 887 .reserve-row
 888   margin-bottom: 15px
 889
 890 .full-width
 891   width: 100%
 892
 893 .game
 894   user-select: none
 895   width: 100%
 896   margin: 0
 897   .board
 898     cursor: pointer
 899
 900 #choices
 901   user-select: none
 902   margin: 0
 903   position: absolute
 904   z-index: 300
 905   overflow-y: inherit
 906   background-color: rgba(0,0,0,0)
 907   img
 908     cursor: pointer
 909     background-color: #e6ee9c
 910     &:hover
 911       background-color: skyblue
 912     &.choice-piece
 913       width: 100%
 914       height: auto
 915       display: block
 916
 917 img.ghost
 918   // NOTE: no need to set z-index here, since opacity is low
 919   position: absolute
 920   opacity: 0.5
 921   top: 0
 922
 923 .incheck-light
 924   background-color: rgba(204, 51, 0, 0.7) !important
 925 .incheck-dark
 926   background-color: rgba(204, 51, 0, 0.9) !important
 927
 928 // TODO: no predefined highlight colors, but layers. How?
 929
 930 .hover-highlight:hover
 931   // TODO: color dependant on board theme, or inner border...
 932   background-color: #C571E6 !important
 933
 934 .highlight
 935   &.light-square
 936     &.lichess
 937       background-color: #cdd26a
 938     &.chesscom
 939       background-color: #f7f783
 940     &.chesstempo
 941       background-color: #9f9fff
 942     &.orangecc
 943       background-color: #fef273
 944   &.dark-square
 945     &.lichess
 946       background-color: #aaa23a
 947     &.chesscom
 948       background-color: #bacb44
 949     &.chesstempo
 950       background-color: #557fff
 951     &.orangecc
 952       background-color: #e8c525
 953   &.middle-square
 954     &.lichess
 955       background-color: #BCBA52
 956     &.chesscom
 957       background-color: #D9E164
 958     &.chesstempo
 959       background-color: #7A8FFF
 960     &.orangecc
 961       background-color: #F3DC4C
 962 </style>