html/js/search.js

/**
 search.js searchs an XML index to HTML files.

 A part of the jsfind project (http://projects.elucidsoft.net/jsfind)
 Copyright (C) 2003 Shawn Garbett

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation; either version 2
 of the License, or (at your option) any later version.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 Contact Info:
 Shawn Garbett <Shawn@eLucidSoft.net>
 http://www.elucidsoft.net
 4037 General Bate Drive
 Nashville, TN 37204
*/

// Constants
var conversion = new String
      ("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXY");

// State variables
var query_left = "";
var search_err = "";
var results    = null;

var watchdog_id = 0;
var watchdog_callback = null;

// Object to hold search results
function Result(title, link, freq)
{
  this.title=title;
  this.link=link;
  this.frequency=Number(freq);
}

// Function to merge (intersect) two result sets
function intersect_results(data)
{
  // If there are no stored results, then these are the results
  if(!results)
  {
    results = data;
    return;
  }

  var output=new Array();

  // There are existing results, to do an intersect...
  for(var i=0; i<results.length; i++)
  {
    for(var j=0; j<data.length; j++)
    {
      if(data[j].title == results[i].title)
      {
        results[i].frequency += data[j].frequency;
        output.push(results[i]);  
        break;
      }
    }
  }

  results = output;
}

/*
 From David Flanagan's, _Javascript:_The Definitive_Guide_, pg. 294-5,
  published by O'Reilly, 4th edition, 2002
*/
function debug(msg)
{
//  return; // Disable debugging

  if(!debug.box)
  {
    debug.box = document.createElement("div");
    debug.box.setAttribute("style",
                           "background-color:white" + 
                           "font-family: monospace; " +
                           "border: solid black 3px; "+
                           "padding: 10px;");

    document.body.appendChild(debug.box);
    debug.box.innerHTML = "<h1 style='test-align:cent'>Debugging Output</h1>";
  }

  var p = document.createElement("p");
  p.appendChild(document.createTextNode(msg));
  debug.box.appendChild(p);
}

// 

// Convert a number into a base 62 alphanumeric number string
function convert(num)
{
  var base = conversion.length;
  var pow = 1;
  var pos = 0;
  var out = "";  

  if(num == 0)
  {
    return "0";
  }

  while (num > 0)
  {
    pos = num % base;
    out = conversion.charAt(pos) + out;
    num = Math.floor(num/base);
    pow *= base;
  }

  return out;
}

function watchdog()
{
  debug ("TIMEOUT!");
  watchdog_callback(new Array());
}

// This function loads the XML document from the specified URL, and when
// it is fully loaded, passes that document and the url to the specified
// handler function.  This function works with any XML document
function loadXML(url, handler, data, result_handler)
{
  debug("loadXML("+url+","+data+")");

  // Timeout operation in 10 seconds
  watchdog_callback = result_handler;
  watchdog_id=setTimeout("watchdog()", 20000);

  debug("setTimeout = "+watchdog_id);

  try 
  {
    // Use the standard DOM Level 2 technique, if it is supported
    if (document.implementation && document.implementation.createDocument)
    {
     // Create a new Document object
      var xmldoc = document.implementation.createDocument("", "", null);

      // Specify what should happen when it finishes loading
      xmldoc.onload = function() { handler(xmldoc, url, data, result_handler); }

      //xmldoc.onerror = docError;
      //xmldoc.addEventListener("load",docError,false);

      // And tell it what URL to load
      xmldoc.load(url);
    }
    // Otherwise use Microsoft's proprietary API for Internet Explorer
    // Something about not following standards once again
    else if (window.ActiveXObject)
    {  
      //var xmldoc = new ActiveXObject("MSXML2.DOMDocument");   // Create doc.
      var xmldoc = new ActiveXObject("Microsoft.XMLDOM");   // Create doc.
      // Specify onload
      xmldoc.onreadystatechange = function()
      {              
        if (xmldoc.readyState == 4) handler(xmldoc, url, data, result_handler);
      }
      xmldoc.load(url);                                     // Start loading!
    }
  }
  catch(ex)
  {
    clearTimeout(watchdog_id);
    debug("clearTimeout = "+watchdog_id);
    debug ("CAUGHT EXCEPTION!");
    result_handler(new Array());
    return false;
  }

  return true;
}

function loadData(xmldoc, url, pos, result_handler)
{
  clearTimeout(watchdog_id);
  debug("clearTimeout = "+watchdog_id);

  debug ("loadData("+url+","+pos+")");

  var data = new Array();

  // Get all entries
  var entries = xmldoc.getElementsByTagName("e");

  if(entries.length > pos)
  {
    // Get the links associated with this query
    var links = entries[pos].getElementsByTagName("l");

    // Dynamically append results to output
    for(var i=0; i<links.length; i++)
    {
      data.push(new Result(links[i].getAttribute("t"),
                           links[i].firstChild.data,
                           links[i].getAttribute("f")));
    }

    intersect_results(data); 

    if(query_left.length > 0)
    {
      doSearch(query_left, result_handler);  
    }
    else
    {
      results.sort(sortResults);
      result_handler(results);
    }
  }
  else
  {
    debug("INTERNAL ERROR, Inconsistent index");
    search_err="INTERNAL ERROR, Inconsistent index";
  }
}

function sortResults(a, b)
{
  return a.frequency - b.frequency;
}

function traverseTree(xmldoc, url, query, result_handler)
{
  clearTimeout(watchdog_id);
  debug("clearTimeout = "+watchdog_id);
 
  debug("traverseTree("+xmldoc+","+url+","+query+")");

  var keys = xmldoc.getElementsByTagName("k");
  var i;

  for(i = 0; i < keys.length; i++)
  {
    var key = keys[i].firstChild.data;
    debug("traverseTree: key="+key+" query="+query);
    if(key != '' && key != null)
    {
      // Case where current key is greater than query, descend
      if(key > query)
      {
        if(key != '' && key != null)
        {
          if(!loadXML(url.replace(".xml","/"+convert(i)+".xml"),
                      traverseTree,query,result_handler))
          {
            debug("Unable to locate key "+query);
            result_handler(new Array());
          }
          // make sure of garbage collection
          xmldoc=null;
          return;
        }
      }
      // Found it!
      else if(key==query)
      {
        if(!loadXML(url.replace(/(\w+\.xml)/, "_$1"),
                    loadData, i, result_handler))
        {
          debug("ERROR: Unable to locate data "+query);
          result_handler(new Array());
        }
        // make sure of garbage collection
        xmldoc=null;
        return;
      }
    }
  }
  // Look past the end...
  if(keys.length == 0 || !loadXML(url.replace(".xml","/"+convert(i)+".xml"),
              traverseTree,query,result_handler))
  {
    debug("Unable to locate key "+query);
    result_handler(new Array());
  }
  // make sure of garbage collection
  xmldoc=null;
  return;
}

function doSearch(query, result_func)
{
  //alert("doSearch("+query+")");
  var pos=query.search(/[\s\+]/);

  if(pos < 0)
  {
    query_left = "";
  }
  else
  {
    query_left = query.slice(pos+1);
    query = query.slice(0,pos);
  } 

  if(!loadXML("0.xml", traverseTree, query.toLowerCase(), result_func))
  {
    debug("ERROR: Couldn't find main index 0.xml");
    search_err = "INTERNAL ERROR: Unable to load main index 0.xml";
  }
}
1	dpavlin	1	/**
2			search.js searchs an XML index to HTML files.
3
4			A part of the jsfind project (http://projects.elucidsoft.net/jsfind)
5			Copyright (C) 2003 Shawn Garbett
6
7			This program is free software; you can redistribute it and/or
8			modify it under the terms of the GNU General Public License
9			as published by the Free Software Foundation; either version 2
10			of the License, or (at your option) any later version.
11
12			This program is distributed in the hope that it will be useful,
13			but WITHOUT ANY WARRANTY; without even the implied warranty of
14			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15			GNU General Public License for more details.
16
17			You should have received a copy of the GNU General Public License
18			along with this program; if not, write to the Free Software
19			Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20
21			Contact Info:
22			Shawn Garbett <Shawn@eLucidSoft.net>
23			http://www.elucidsoft.net
24			4037 General Bate Drive
25			Nashville, TN 37204
26			*/
27
28			// Constants
29			var conversion = new String
30			("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXY");
31
32			// State variables
33			var query_left = "";
34			var search_err = "";
35			var results = null;
36
37			var watchdog_id = 0;
38			var watchdog_callback = null;
39
40			// Object to hold search results
41			function Result(title, link, freq)
42			{
43			this.title=title;
44			this.link=link;
45			this.frequency=Number(freq);
46			}
47
48			// Function to merge (intersect) two result sets
49			function intersect_results(data)
50			{
51			// If there are no stored results, then these are the results
52			if(!results)
53			{
54			results = data;
55			return;
56			}
57
58			var output=new Array();
59
60			// There are existing results, to do an intersect...
61			for(var i=0; i<results.length; i++)
62			{
63			for(var j=0; j<data.length; j++)
64			{
65			if(data[j].title == results[i].title)
66			{
67			results[i].frequency += data[j].frequency;
68			output.push(results[i]);
69			break;
70			}
71			}
72			}
73
74			results = output;
75			}
76
77			/*
78			From David Flanagan's, _Javascript:_The Definitive_Guide_, pg. 294-5,
79			published by O'Reilly, 4th edition, 2002
80			*/
81			function debug(msg)
82			{
83			// return; // Disable debugging
84
85			if(!debug.box)
86			{
87			debug.box = document.createElement("div");
88			debug.box.setAttribute("style",
89			"background-color:white" +
90			"font-family: monospace; " +
91			"border: solid black 3px; "+
92			"padding: 10px;");
93
94			document.body.appendChild(debug.box);
95			debug.box.innerHTML = "<h1 style='test-align:cent'>Debugging Output</h1>";
96			}
97
98			var p = document.createElement("p");
99			p.appendChild(document.createTextNode(msg));
100			debug.box.appendChild(p);
101			}
102
103			//
104
105			// Convert a number into a base 62 alphanumeric number string
106			function convert(num)
107			{
108			var base = conversion.length;
109			var pow = 1;
110			var pos = 0;
111			var out = "";
112
113			if(num == 0)
114			{
115			return "0";
116			}
117
118			while (num > 0)
119			{
120			pos = num % base;
121			out = conversion.charAt(pos) + out;
122			num = Math.floor(num/base);
123			pow *= base;
124			}
125
126			return out;
127			}
128
129			function watchdog()
130			{
131			debug ("TIMEOUT!");
132			watchdog_callback(new Array());
133			}
134
135			// This function loads the XML document from the specified URL, and when
136			// it is fully loaded, passes that document and the url to the specified
137			// handler function. This function works with any XML document
138			function loadXML(url, handler, data, result_handler)
139			{
140			debug("loadXML("+url+","+data+")");
141
142			// Timeout operation in 10 seconds
143			watchdog_callback = result_handler;
144			watchdog_id=setTimeout("watchdog()", 20000);
145
146			debug("setTimeout = "+watchdog_id);
147
148			try
149			{
150			// Use the standard DOM Level 2 technique, if it is supported
151			if (document.implementation && document.implementation.createDocument)
152			{
153			// Create a new Document object
154			var xmldoc = document.implementation.createDocument("", "", null);
155
156			// Specify what should happen when it finishes loading
157			xmldoc.onload = function() { handler(xmldoc, url, data, result_handler); }
158
159			//xmldoc.onerror = docError;
160			//xmldoc.addEventListener("load",docError,false);
161
162			// And tell it what URL to load
163			xmldoc.load(url);
164			}
165			// Otherwise use Microsoft's proprietary API for Internet Explorer
166			// Something about not following standards once again
167			else if (window.ActiveXObject)
168			{
169			//var xmldoc = new ActiveXObject("MSXML2.DOMDocument"); // Create doc.
170			var xmldoc = new ActiveXObject("Microsoft.XMLDOM"); // Create doc.
171			// Specify onload
172			xmldoc.onreadystatechange = function()
173			{
174			if (xmldoc.readyState == 4) handler(xmldoc, url, data, result_handler);
175			}
176			xmldoc.load(url); // Start loading!
177			}
178			}
179			catch(ex)
180			{
181			clearTimeout(watchdog_id);
182			debug("clearTimeout = "+watchdog_id);
183			debug ("CAUGHT EXCEPTION!");
184			result_handler(new Array());
185			return false;
186			}
187
188			return true;
189			}
190
191			function loadData(xmldoc, url, pos, result_handler)
192			{
193			clearTimeout(watchdog_id);
194			debug("clearTimeout = "+watchdog_id);
195
196			debug ("loadData("+url+","+pos+")");
197
198			var data = new Array();
199
200			// Get all entries
201			var entries = xmldoc.getElementsByTagName("e");
202
203			if(entries.length > pos)
204			{
205			// Get the links associated with this query
206			var links = entries[pos].getElementsByTagName("l");
207
208			// Dynamically append results to output
209			for(var i=0; i<links.length; i++)
210			{
211			data.push(new Result(links[i].getAttribute("t"),
212			links[i].firstChild.data,
213			links[i].getAttribute("f")));
214			}
215
216			intersect_results(data);
217
218			if(query_left.length > 0)
219			{
220			doSearch(query_left, result_handler);
221			}
222			else
223			{
224			results.sort(sortResults);
225			result_handler(results);
226			}
227			}
228			else
229			{
230			debug("INTERNAL ERROR, Inconsistent index");
231			search_err="INTERNAL ERROR, Inconsistent index";
232			}
233			}
234
235			function sortResults(a, b)
236			{
237			return a.frequency - b.frequency;
238			}
239
240			function traverseTree(xmldoc, url, query, result_handler)
241			{
242			clearTimeout(watchdog_id);
243			debug("clearTimeout = "+watchdog_id);
244
245			debug("traverseTree("+xmldoc+","+url+","+query+")");
246
247			var keys = xmldoc.getElementsByTagName("k");
248			var i;
249
250			for(i = 0; i < keys.length; i++)
251			{
252			var key = keys[i].firstChild.data;
253			debug("traverseTree: key="+key+" query="+query);
254			if(key != '' && key != null)
255			{
256			// Case where current key is greater than query, descend
257			if(key > query)
258			{
259			if(key != '' && key != null)
260			{
261			if(!loadXML(url.replace(".xml","/"+convert(i)+".xml"),
262			traverseTree,query,result_handler))
263			{
264			debug("Unable to locate key "+query);
265	dpavlin	2	result_handler(new Array());
266	dpavlin	1	}
267			// make sure of garbage collection
268			xmldoc=null;
269			return;
270			}
271			}
272			// Found it!
273			else if(key==query)
274			{
275			if(!loadXML(url.replace(/(\w+\.xml)/, "_$1"),
276			loadData, i, result_handler))
277			{
278			debug("ERROR: Unable to locate data "+query);
279	dpavlin	2	result_handler(new Array());
280	dpavlin	1	}
281			// make sure of garbage collection
282			xmldoc=null;
283			return;
284			}
285			}
286			}
287			// Look past the end...
288	dpavlin	2	if(keys.length == 0 \|\| !loadXML(url.replace(".xml","/"+convert(i)+".xml"),
289	dpavlin	1	traverseTree,query,result_handler))
290			{
291			debug("Unable to locate key "+query);
292	dpavlin	2	result_handler(new Array());
293	dpavlin	1	}
294			// make sure of garbage collection
295			xmldoc=null;
296			return;
297			}
298
299			function doSearch(query, result_func)
300			{
301			//alert("doSearch("+query+")");
302			var pos=query.search(/[\s\+]/);
303
304			if(pos < 0)
305			{
306			query_left = "";
307			}
308			else
309			{
310			query_left = query.slice(pos+1);
311			query = query.slice(0,pos);
312			}
313
314			if(!loadXML("0.xml", traverseTree, query.toLowerCase(), result_func))
315			{
316			debug("ERROR: Couldn't find main index 0.xml");
317			search_err = "INTERNAL ERROR: Unable to load main index 0.xml";
318			}
319			}