reveal-js-base-theme/plugin/search/search.js

/*
 * Handles finding a text string anywhere in the slides and showing the next occurrence to the user
 * by navigatating to that slide and highlighting it.
 *
 * By Jon Snyder <snyder.jon@gmail.com>, February 2013
 */

var RevealSearch = (function() {

	var matchedSlides;
	var currentMatchedIndex;
	var searchboxDirty;
	var myHilitor;

// Original JavaScript code by Chirp Internet: www.chirp.com.au
// Please acknowledge use of this code by including this header.
// 2/2013 jon: modified regex to display any match, not restricted to word boundaries.

function Hilitor(id, tag)
{

  var targetNode = document.getElementById(id) || document.body;
  var hiliteTag = tag || "EM";
  var skipTags = new RegExp("^(?:" + hiliteTag + "|SCRIPT|FORM|SPAN)$");
  var colors = ["#ff6", "#a0ffff", "#9f9", "#f99", "#f6f"];
  var wordColor = [];
  var colorIdx = 0;
  var matchRegex = "";
  var matchingSlides = [];

  this.setRegex = function(input)
  {
    input = input.replace(/^[^\w]+|[^\w]+$/g, "").replace(/[^\w'-]+/g, "|");
    matchRegex = new RegExp("(" + input + ")","i");
  }

  this.getRegex = function()
  {
    return matchRegex.toString().replace(/^\/\\b\(|\)\\b\/i$/g, "").replace(/\|/g, " ");
  }

  // recursively apply word highlighting
  this.hiliteWords = function(node)
  {
    if(node == undefined || !node) return;
    if(!matchRegex) return;
    if(skipTags.test(node.nodeName)) return;

    if(node.hasChildNodes()) {
      for(var i=0; i < node.childNodes.length; i++)
        this.hiliteWords(node.childNodes[i]);
    }
    if(node.nodeType == 3) { // NODE_TEXT
      if((nv = node.nodeValue) && (regs = matchRegex.exec(nv))) {
      	//find the slide's section element and save it in our list of matching slides
      	var secnode = node.parentNode;
      	while (secnode.nodeName != 'SECTION') {
      		secnode = secnode.parentNode;
      	}
      	
      	var slideIndex = Reveal.getIndices(secnode);
      	var slidelen = matchingSlides.length;
      	var alreadyAdded = false;
      	for (var i=0; i < slidelen; i++) {
      		if ( (matchingSlides[i].h === slideIndex.h) && (matchingSlides[i].v === slideIndex.v) ) {
      			alreadyAdded = true;
      		}
      	}
      	if (! alreadyAdded) {
      		matchingSlides.push(slideIndex);
      	}
      	
        if(!wordColor[regs[0].toLowerCase()]) {
          wordColor[regs[0].toLowerCase()] = colors[colorIdx++ % colors.length];
        }

        var match = document.createElement(hiliteTag);
        match.appendChild(document.createTextNode(regs[0]));
        match.style.backgroundColor = wordColor[regs[0].toLowerCase()];
        match.style.fontStyle = "inherit";
        match.style.color = "#000";

        var after = node.splitText(regs.index);
        after.nodeValue = after.nodeValue.substring(regs[0].length);
        node.parentNode.insertBefore(match, after);
      }
    }
  };

  // remove highlighting
  this.remove = function()
  {
    var arr = document.getElementsByTagName(hiliteTag);
    while(arr.length && (el = arr[0])) {
      el.parentNode.replaceChild(el.firstChild, el);
    }
  };

  // start highlighting at target node
  this.apply = function(input)
  {
    if(input == undefined || !input) return;
    this.remove();
    this.setRegex(input);
    this.hiliteWords(targetNode);
    return matchingSlides;
  };

}

	function openSearch() {
		//ensure the search term input dialog is visible and has focus:
		var inputbox = document.getElementById("searchinput");
		inputbox.style.display = "inline";
		inputbox.focus();
		inputbox.select();
	}

	function toggleSearch() {
		var inputbox = document.getElementById("searchinput");
		if (inputbox.style.display !== "inline") {
			openSearch();
		}
		else {
			inputbox.style.display = "none";
			myHilitor.remove();
		}
	}

	function doSearch() {
		//if there's been a change in the search term, perform a new search:
		if (searchboxDirty) {
			var searchstring = document.getElementById("searchinput").value;

			//find the keyword amongst the slides
			myHilitor = new Hilitor("slidecontent");
			matchedSlides = myHilitor.apply(searchstring);
			currentMatchedIndex = 0;
		}

		//navigate to the next slide that has the keyword, wrapping to the first if necessary
		if (matchedSlides.length && (matchedSlides.length <= currentMatchedIndex)) {
			currentMatchedIndex = 0;
		}
		if (matchedSlides.length > currentMatchedIndex) {
			Reveal.slide(matchedSlides[currentMatchedIndex].h, matchedSlides[currentMatchedIndex].v);
			currentMatchedIndex++;
		}
	}

	var dom = {};
	dom.wrapper = document.querySelector( '.reveal' );

	if( !dom.wrapper.querySelector( '.searchbox' ) ) {
			var searchElement = document.createElement( 'div' );
			searchElement.id = "searchinputdiv";
			searchElement.classList.add( 'searchdiv' );
			searchElement.innerHTML = '<span><input type="text" id="searchinput" class="searchinput"/><img src="css/theme/assets/searchicon.png" id="searchbutton" class="searchicon"/></span>';
			dom.wrapper.appendChild( searchElement );
	}

	document.getElementById("searchbutton").addEventListener( 'click', function(event) {
		toggleSearch();
	}, false );

	document.getElementById("searchinput").addEventListener( 'keyup', function( event ) {
		switch (event.keyCode) {
			case 13:
				event.preventDefault();
				doSearch();
				searchboxDirty = false;
				break;
			default:
				searchboxDirty = true;
		}
	}, false );

	// Open the search when the 's' key is hit (yes, this conflicts with the notes plugin, disabling for now)
	/*
	document.addEventListener( 'keydown', function( event ) {
		// Disregard the event if the target is editable or a
		// modifier is present
		if ( document.querySelector( ':focus' ) !== null || event.shiftKey || event.altKey || event.ctrlKey || event.metaKey ) return;

		if( event.keyCode === 83 ) {
			event.preventDefault();
			openSearch();
		}
	}, false );
*/
	return { open: openSearch };
})();