tictactoe-check-win.js

/*jslint indent: 2, maxlen: 80, continue: false, unparam: false, node: true */
/* -*- tab-width: 2 -*- */
'use strict';


function displayGame(field, colSep, rowSep) {
  return field.map(String).join(rowSep).replace(/,/g, colSep);
}


function mg0(txt, rgx) { return (rgx.exec(txt) || false)[0]; }

function checkWinner(gst) {
  var dis = displayGame(gst, '', ':'), size = gst.length,
    rxHoriz = new RegExp('\\b(1{#}|2{#})\\b'.replace(/#/g, size)),
    rxVert = new RegExp('1(.{#}1){_}|2(.{#}2){_}'.replace(/#/g, size
      ).replace(/_/g, size - 1));
  return (mg0(dis, rxHoriz) || mg0(dis, rxVert) || '-').substr(0, 1);
}


function luciferCheck(gst) {
  var winner = 0, size = gst.length, x, y;

  // Horizontal Check
  function horiz(a, b) {
    console.log('horiz?', { y: y, a: a, b: b, eq: (a === b) });
    return ((a === b) ? a : 0);
  }
  for (y = 0; y < size; y += 1) {
    winner = gst[y].reduce(horiz);
    console.log('horiz?', { winner: winner });
    if (winner) { return winner; }
  }

  // Vertical Check
  function vert(a, b) {
    console.log('vert?', { x: x, ax: a[x], bx: b[x], eq: (a[x] === b[x]) });
    return (a[x] === b[x] ? a[x] : 0);
    // Nope: Returning a number will crash the [x] lookup in the next iteration.
    // Log line: vert? { x: 0, ax: undefined, bx: 1, eq: false }
  }
  for (x = 0; x < size; x += 1) {
    winner = gst.reduce(vert);
    console.log('vert?', { winner: winner });
    if (winner) { return winner; }
  }

  return 0;
}


function eachFor(f, a) { a.forEach(f); }

eachFor(function (field) {
  console.log([
    displayGame(field, ' ', '\n'),
    checkWinner(field),
    luciferCheck(field),
  ].join('\t') + '\n');
}, [

  [ [ 0, 2, 2 ],
    [ 1, 0, 2 ],
    [ 1, 0, 1 ] ],

  [ [ 2, 2, 2 ],
    [ 1, 0, 2 ],
    [ 1, 0, 1 ] ],

  [ [ 1, 2, 2 ],
    [ 1, 0, 2 ],
    [ 1, 0, 1 ] ],

]);