MediaWiki:Common.js: Difference between revisions

Revision as of 11:48, 29 September 2025

/* ImageMap Highlighter
   - Highlights mapped regions on hover/focus and syncs with legend items
   - Builds a compact multi-column legend (grid is styled in CSS)
   Public domain; based on user:קיפודנחש (hewiki)
*/
(function ($, mw) {
  'use strict';

  // guard against double-loading
  if (window.IMH_GRID_LOADED) return;
  window.IMH_GRID_LOADED = true;

  // ---- Config ----
  var ART = 'imageMapHighlighterArtefacts'; // artifact class
  var WRAP_CLASS = 'im-wrap';
  var liHighlightClass = 'liHighlighting';
  var specialAreaMark = 'area_mark';
  var specialLiClassesMark = 'list_classes';
  var hilightDivMarker = '.imageMapHighlighter';
  var areaHighLighting = { fillStyle: 'rgba(0,0,0,0.35)', strokeStyle: 'yellow', lineJoin: 'round', lineWidth: 2 };
  var he = mw && mw.config && mw.config.get('wgUserLanguage') === 'he';
  var expandLegend = he ? 'הצגת מקרא' : 'Show legend';
  var collapseLegend = he ? 'הסתרת המקרא' : 'Hide legend';
  var liEvents = 'mouseover mouseout focus blur';
  var mouseEvents = 'mouseover mouseout';
  var highlightEvents = ['mouseover', 'focus'];

  // ---- Drawing (with scaling) ----
  function drawMarker(context, areas) {
    var sx = context._imhSx || 1; // natural→rendered scale X
    var sy = context._imhSy || 1; // natural→rendered scale Y

    function drawPolyScaled(coords) {
      // coords: [x1,y1, x2,y2, ...] in natural image coords
      context.moveTo(coords[0] * sx, coords[1] * sy);
      for (var i = 2; i < coords.length; i += 2) {
        context.lineTo(coords[i] * sx, coords[i + 1] * sy);
      }
    }

    for (var i = 0; i < areas.length; i++) {
      var a = areas[i];
      var coords = (a.coords || '').split(',').map(Number);
      if (!coords.length) continue;

      context.beginPath();
      switch (a.shape) {
        case 'circle': {
          var x = coords[0] * sx;
          var y = coords[1] * sy;
          // use geometric-mean scale for radius if x/y scales differ
          var r = coords[2] * Math.sqrt((sx * sx + sy * sy) / 2);
          context.arc(x, y, r, 0, Math.PI * 2);
          break;
        }
        case 'poly':
          drawPolyScaled(coords);
          break;
        case 'rect':
        case null:
        case '':
        default:
          // Some MW versions omit shape="rect"
          drawPolyScaled([coords[0], coords[1], coords[0], coords[3], coords[2], coords[3], coords[2], coords[1]]);
      }
      context.closePath();
      context.stroke();
      context.fill();
    }
  }

  // ---- Legend hover handler ----
  function mouseAction(e) {
    var $this = $(this);
    var activate = highlightEvents.indexOf(e.type) >= 0;
    var cap = ($this.find('.im-label a').text() || $this.find('.im-label').text() || $this.text()).trim();
    var $legend = $this.closest('.im-legend');
    var context = $legend.data('context');
    var special = $legend.data(specialAreaMark);

    $this.toggleClass(liHighlightClass, activate);
    if (!context) return;

    context.clearRect(0, 0, context.canvas.width, context.canvas.height);

    $legend.find('.im-row').each(function () {
      var $row = $(this);
      var rowCap = ($row.find('.im-label a').text() || $row.find('.im-label').text() || $row.text()).trim();
      var param = (activate && rowCap === cap)
        ? (special && special.hover) || areaHighLighting
        : (special && special.nover && (special.nover[rowCap] || special.nover.default));
      if (param) {
        $.extend(context, param);
        drawMarker(context, $row.data('areas') || []);
      }
    });
  }

  // ---- Build one imagemap ----
  function handleOneMap() {
    var $img = $(this);
    if ($img.data('imhProcessed')) return; // once per image

    // wait for intrinsic dimensions
    var el = $img[0];
    if (!el.complete || !el.naturalWidth) {
      $img.one('load', handleOneMap);
      return;
    }

    // Locate the <map>
    var $map = (function () {
      var m = $img.parent().siblings('map:first');
      if (m.length) return m;
      var usemap = $img.attr('usemap'); // "#name"
      if (usemap) {
        var name = usemap.replace(/^#/, '');
        m = $('map[name="' + name + '"]');
        if (m.length) return m.first();
      }
      return $img.closest(hilightDivMarker).find('map:first');
    })();
    if (!$map.length || !$map.find('area').length) return;

    // Natural vs rendered sizes
    var natW = el.naturalWidth;
    var natH = el.naturalHeight;
    var rect = el.getBoundingClientRect(); // rendered CSS size (fractional ok)
    var cssW = rect.width;
    var cssH = rect.height;

    // Scale factors from coords → rendered pixels
    var sx = cssW / natW;
    var sy = cssH / natH;

    // Hi-DPI canvas
    var dpr = window.devicePixelRatio || 1;

    // Create/clean wrapper
    var $wrap = $img.closest('.' + WRAP_CLASS);
    if (!$wrap.length) {
      $wrap = $('<div>', { 'class': WRAP_CLASS })
        .css({ position: 'relative', width: cssW + 'px', height: cssH + 'px' });
      $img.before($wrap);
      $wrap.append($img);
    } else {
      $wrap.css({ width: cssW + 'px', height: cssH + 'px' });
      $wrap.find('canvas.' + ART + ', img.' + ART).remove();
    }

    // Remove previous legend/toggle artifacts if re-run
    $wrap.nextAll('div.im-legend, ol.' + ART + ', hr.' + ART + ', .mw-collapsible-toggle.im-toggle').remove();

    // Layer sandwich: bg (z0), canvas (z1), original (z2, transparent but keeps events)
    var layerCSS = { position: 'absolute', top: 0, left: 0, width: cssW + 'px', height: cssH + 'px', border: 0 };
    var $bg = $('<img>', { 'class': ART, src: $img.attr('src') }).css($.extend({ zIndex: 0, display: 'block' }, layerCSS));
    var $cv = $('<canvas>', { 'class': ART })
      .css($.extend({ zIndex: 1 }, layerCSS))
      .attr({ width: Math.round(cssW * dpr), height: Math.round(cssH * dpr) });

    var ctx = $cv[0].getContext('2d');
    ctx.setTransform(dpr, 0, 0, dpr, 0, 0); // draw in CSS px
    $.extend(ctx, areaHighLighting);
    ctx._imhSx = sx;
    ctx._imhSy = sy;

    // Put original image on top but transparent so it still handles mouse events
    $img.css($.extend({ zIndex: 2, opacity: 0, display: 'block' }, layerCSS));

    $wrap.append($bg).append($cv);
    $img.data('imhProcessed', true);

    // ---- Legend ----
    var $legend = $('<div>', {
      'class': ART + ' im-legend mw-collapsible mw-collapsed'
    }).attr({ 'data-expandtext': expandLegend, 'data-collapsetext': collapseLegend })
      .data(specialAreaMark, $img.closest(hilightDivMarker).data(specialAreaMark))
      .data('context', ctx);

    var $grid = $('<div class="im-grid" role="list"></div>');
    $legend.append($grid);

    // Place legend below image
    $wrap.after($('<hr>', { 'class': ART }).css('clear', 'both')).after($legend);

    var rowsByTitle = Object.create(null);
    var idx = 0;
    var $someRow;
    var specialLiClasses = $img.closest(hilightDivMarker).data(specialLiClassesMark);

    $map.find('area').each(function () {
      var title = this.title || ('Area ' + (idx + 1));
      var href = this.href || '#';
      var key = title;
      var $row = rowsByTitle[key];

      if (!$row) {
        idx += 1;
        $row = $('<div>', { 'class': ART + ' im-row', 'role': 'listitem', 'tabindex': '0' })
          .append($('<span class="im-num">').text(idx))
          .append($('<span class="im-label">').append($('<a>', { href: href }).text(title)))
          .on(liEvents, mouseAction)
          .data('areas', []);
        if (specialLiClasses) {
          var extra = specialLiClasses[title] || specialLiClasses['default'];
          if (extra) $row.addClass(extra);
        }
        rowsByTitle[key] = $row;
        $grid.append($row);
      }

      // link area <-> legend row
      $row.data('areas').push(this);
      $someRow = $row;
      $(this).on(mouseEvents, function (e) { $row.trigger(e.type); });
    });

    if ($someRow) $someRow.trigger('mouseout');

    // Activate collapsible and move toggle inside the bordered legend box
    mw.loader.using('jquery.makeCollapsible').then(function () {
      $legend.makeCollapsible();

      // MediaWiki adds the toggle as a sibling; move it inside for nicer layout
      var $toggle = $legend.prev('.mw-collapsible-toggle');
      if (!$toggle.length) $toggle = $legend.next('.mw-collapsible-toggle');
      if ($toggle.length) {
        $toggle.addClass('im-toggle');
        $legend.prepend($toggle);
      }
    });
  }

  // ---- Init (only where needed) ----
  function init($scope) {
    var $root = ($scope && $scope.length) ? $scope : $(document);
    var $targets = $root.find(hilightDivMarker + ' img');
    if (!$targets.length) return;
    $targets.each(handleOneMap);
  }

  // Run on ready and on content updates (VE/Ajax)
  $(function () { init(); });
  mw.hook('wikipage.content').add(function ($c) { init($c); });

})(jQuery, mw);