out/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 index_path = "";

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

  var debug_div = element_id('debug');

  if (debug_div) debug_div.innerHTML += msg+"<br/>\n";
}

// 

// 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());
}

var xmldoc;

// 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
      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)
    {  
      xmldoc = new ActiveXObject("Microsoft.XMLDOM");   // Create doc.
      if (! xmldoc) xmldoc = new ActiveXObject("MSXML2.DOMDocument");   // 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(index_path, 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(index_name,query, result_func)
{
  //alert("doSearch("+index_name+","+query+")");
  var pos=query.search(/[\s\+]/);
  if (index_name) index_path = index_name+'/';

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

  if(!loadXML(index_path+"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	391	/**
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			var index_path = "";
37
38			var watchdog_id = 0;
39			var watchdog_callback = null;
40
41			// Object to hold search results
42			function Result(title, link, freq)
43			{
44			this.title=title;
45			this.link=link;
46			this.frequency=Number(freq);
47			}
48
49			// Function to merge (intersect) two result sets
50			function intersect_results(data)
51			{
52			// If there are no stored results, then these are the results
53			if(!results)
54			{
55			results = data;
56			return;
57			}
58
59			var output=new Array();
60
61			// There are existing results, to do an intersect...
62			for(var i=0; i<results.length; i++)
63			{
64			for(var j=0; j<data.length; j++)
65			{
66			if(data[j].title == results[i].title)
67			{
68			results[i].frequency += data[j].frequency;
69			output.push(results[i]);
70			break;
71			}
72			}
73			}
74
75			results = output;
76			}
77
78			/*
79			From David Flanagan's, _Javascript:_The Definitive_Guide_, pg. 294-5,
80			published by O'Reilly, 4th edition, 2002
81			*/
82			function debug(msg)
83			{
84	dpavlin	396	// return; // Disable debugging
85	dpavlin	391
86	dpavlin	464	var debug_div = element_id('debug');
87	dpavlin	391
88	dpavlin	464	if (debug_div) debug_div.innerHTML += msg+"<br/>\n";
89	dpavlin	391	}
90
91			//
92
93			// Convert a number into a base 62 alphanumeric number string
94			function convert(num)
95			{
96			var base = conversion.length;
97			var pow = 1;
98			var pos = 0;
99			var out = "";
100
101			if(num == 0)
102			{
103			return "0";
104			}
105
106			while (num > 0)
107			{
108			pos = num % base;
109			out = conversion.charAt(pos) + out;
110			num = Math.floor(num/base);
111			pow *= base;
112			}
113
114			return out;
115			}
116
117			function watchdog()
118			{
119			debug ("TIMEOUT!");
120			watchdog_callback(new Array());
121			}
122
123	dpavlin	469	var xmldoc;
124
125	dpavlin	391	// This function loads the XML document from the specified URL, and when
126			// it is fully loaded, passes that document and the url to the specified
127			// handler function. This function works with any XML document
128			function loadXML(url, handler, data, result_handler)
129			{
130			debug("loadXML("+url+","+data+")");
131
132			// Timeout operation in 10 seconds
133			watchdog_callback = result_handler;
134			watchdog_id=setTimeout("watchdog()", 20000);
135
136			debug("setTimeout = "+watchdog_id);
137
138			try
139			{
140			// Use the standard DOM Level 2 technique, if it is supported
141			if (document.implementation && document.implementation.createDocument)
142			{
143			// Create a new Document object
144	dpavlin	450	xmldoc = document.implementation.createDocument("", "", null);
145	dpavlin	391
146			// Specify what should happen when it finishes loading
147			xmldoc.onload = function() { handler(xmldoc, url, data, result_handler); }
148
149			//xmldoc.onerror = docError;
150			//xmldoc.addEventListener("load",docError,false);
151
152			// And tell it what URL to load
153			xmldoc.load(url);
154			}
155			// Otherwise use Microsoft's proprietary API for Internet Explorer
156			// Something about not following standards once again
157			else if (window.ActiveXObject)
158			{
159	dpavlin	450	xmldoc = new ActiveXObject("Microsoft.XMLDOM"); // Create doc.
160			if (! xmldoc) xmldoc = new ActiveXObject("MSXML2.DOMDocument"); // Create doc.
161	dpavlin	391	// Specify onload
162			xmldoc.onreadystatechange = function()
163			{
164			if (xmldoc.readyState == 4) handler(xmldoc, url, data, result_handler);
165			}
166			xmldoc.load(url); // Start loading!
167			}
168			}
169			catch(ex)
170			{
171			clearTimeout(watchdog_id);
172			debug("clearTimeout = "+watchdog_id);
173			debug ("CAUGHT EXCEPTION!");
174			result_handler(new Array());
175			return false;
176			}
177
178			return true;
179			}
180
181			function loadData(xmldoc, url, pos, result_handler)
182			{
183			clearTimeout(watchdog_id);
184			debug("clearTimeout = "+watchdog_id);
185
186			debug ("loadData("+url+","+pos+")");
187
188			var data = new Array();
189
190			// Get all entries
191			var entries = xmldoc.getElementsByTagName("e");
192
193			if(entries.length > pos)
194			{
195			// Get the links associated with this query
196			var links = entries[pos].getElementsByTagName("l");
197
198			// Dynamically append results to output
199			for(var i=0; i<links.length; i++)
200			{
201			data.push(new Result(links[i].getAttribute("t"),
202			links[i].firstChild.data,
203			links[i].getAttribute("f")));
204			}
205
206			intersect_results(data);
207
208			if(query_left.length > 0)
209			{
210			doSearch(index_path, query_left, result_handler);
211			}
212			else
213			{
214			results.sort(sortResults);
215			result_handler(results);
216			}
217			}
218			else
219			{
220			debug("INTERNAL ERROR, Inconsistent index");
221			search_err="INTERNAL ERROR, Inconsistent index";
222			}
223			}
224
225			function sortResults(a, b)
226			{
227			return a.frequency - b.frequency;
228			}
229
230			function traverseTree(xmldoc, url, query, result_handler)
231			{
232			clearTimeout(watchdog_id);
233			debug("clearTimeout = "+watchdog_id);
234
235			debug("traverseTree("+xmldoc+","+url+","+query+")");
236
237			var keys = xmldoc.getElementsByTagName("k");
238			var i;
239
240			for(i = 0; i < keys.length; i++)
241			{
242			var key = keys[i].firstChild.data;
243			debug("traverseTree: key="+key+" query="+query);
244			if(key != '' && key != null)
245			{
246			// Case where current key is greater than query, descend
247			if(key > query)
248			{
249			if(key != '' && key != null)
250			{
251			if(!loadXML(url.replace(".xml","/"+convert(i)+".xml"),
252			traverseTree,query,result_handler))
253			{
254			debug("Unable to locate key "+query);
255			result_handler(new Array());
256			}
257			// make sure of garbage collection
258			xmldoc=null;
259			return;
260			}
261			}
262			// Found it!
263			else if(key==query)
264			{
265			if(!loadXML(url.replace(/(\w+\.xml)/, "_$1"),
266			loadData, i, result_handler))
267			{
268			debug("ERROR: Unable to locate data "+query);
269			result_handler(new Array());
270			}
271			// make sure of garbage collection
272			xmldoc=null;
273			return;
274			}
275			}
276			}
277			// Look past the end...
278			if(keys.length == 0 \|\| !loadXML(url.replace(".xml","/"+convert(i)+".xml"),
279			traverseTree,query,result_handler))
280			{
281			debug("Unable to locate key "+query);
282			result_handler(new Array());
283			}
284			// make sure of garbage collection
285			xmldoc=null;
286			return;
287			}
288
289			function doSearch(index_name,query, result_func)
290			{
291			//alert("doSearch("+index_name+","+query+")");
292			var pos=query.search(/[\s\+]/);
293			if (index_name) index_path = index_name+'/';
294
295			if(pos < 0)
296			{
297			query_left = "";
298			}
299			else
300			{
301			query_left = query.slice(pos+1);
302			query = query.slice(0,pos);
303			}
304
305			if(!loadXML(index_path+"0.xml", traverseTree, query.toLowerCase(), result_func))
306			{
307			debug("ERROR: Couldn't find main index 0.xml");
308			search_err = "INTERNAL ERROR: Unable to load main index 0.xml";
309			}
310			}