using System;
using System.Collections.Specialized;
using System.Xml.Serialization;
using System.Text.RegularExpressions;
using System.Collections;
using System.Collections.Generic;
using Searcharoo.Common;
namespace Searcharoo.Engine
{
public class Search
{
#region Private Fields: _Stemmer, _Stopper, _GoChecker, _DisplayTime, _Matches
/// <summary>Stemmer to use</summary>
private IStemming _Stemmer;
/// <summary>Stopper to use</summary>
private IStopper _Stopper;
/// <summary>Go word parser to use</summary>
private IGoWord _GoChecker;
/// <summary>Display string: time the search too</summary>
private string _DisplayTime;
/// <summary>Display string: matches (links and number of)</summary>
private string _Matches = "";
/// <summary>Number of results with geolocation v6</summary>
private int _GeolocCount = 0;
#endregion
#region Public Properties: SearchQueryMatchHtml, DisplayTime
public string SearchQueryMatchHtml
{
get { return _Matches; }
set { _Matches = value; }
}
public string DisplayTime
{
get { return _DisplayTime; }
set { _DisplayTime = value; }
}
public int GeocodedMatches
{
get { return _GeolocCount; }
}
#endregion
/// <summary>
/// Legacy method signature (pre v6)
/// </summary>
public SortedList GetResults(string searchterm, Catalog catalog)
{
return GetResults(searchterm, catalog, false); // all results, including but not limited to geoloc
}
//public SortedList GetResults(string searchterm, Catalog catalog, bool geolocOnly)
//{
// return GetResults(searchterm, catalog, false, new Cache());
//}
/// <summary>
/// v6
/// </summary>
/// <param name="searchterm">search query</param>
/// <param name="catalog">catalog to search</param>
/// <param name="geolocOnly">If true, ONLY return results with a lat/long</param>
/// <param name="cache">Cache of page 'content'</param>
/// <returns>ResultFile SortedList for display</returns>
public SortedList GetResults(string searchterm, Catalog catalog, bool geolocOnly)
{
SortedList output = new SortedList();
// ----------------------- DOING A SEARCH -----------------------
if ((null != searchterm) && (null != catalog))
{
SetPreferences();
string[] searchTermArray = null, searchTermDisplay = null;
/****** Too *********/
Regex r = new Regex(@"\s+"); //remove all whitespace
searchterm = r.Replace(searchterm, " ");// to a single space
searchTermArray = searchterm.Split(' '); // then split
searchTermDisplay = (string[])searchTermArray.Clone();
for (int i = 0; i < searchTermArray.Length; i++)
{
if (_GoChecker.IsGoWord(searchTermArray[i]))
{ // was a Go word, just Lower it
searchTermArray[i] = searchTermArray[i].ToLower();
}
else
{ // Not a Go word, apply stemming
searchTermArray[i] = searchTermArray[i].Trim(' ', '?', '\"', ',', '\'', ';', ':', '.', '(', ')').ToLower();
searchTermArray[i] = _Stemmer.StemWord(searchTermArray[i].ToString());
}
}
if (searchterm == String.Empty)
{
// After trimming the search term, it was found to be empty!
return output;
}
else
{ // we have a search term!
DateTime start = DateTime.Now; // to show 'time taken' to perform search
// Array of arrays of results that match ONE of the search criteria
Dictionary<File, List<int>>[] searchResultsArrayArray = new Dictionary<File, List<int>>[searchTermArray.Length];
// finalResultsArray is populated with pages that *match* ALL the search criteria
HybridDictionary finalResultsArray = new HybridDictionary();
bool botherToFindMatches = true;
int indexOfShortestResultSet = -1, lengthOfShortestResultSet = -1;
for (int i = 0; i < searchTermArray.Length; i++)
{ // ##### THE SEARCH #####
searchResultsArrayArray[i] = catalog.Search(searchTermArray[i].ToString());
if (null == searchResultsArrayArray[i])
{
_Matches += searchTermDisplay[i] + " <font color=gray style='font-size:xx-small'>(not found)</font> ";
botherToFindMatches = false; // if *any one* of the terms isn't found, there won't be a 'set' of Matches
}
else
{
int resultsInThisSet = searchResultsArrayArray[i].Count;
_Matches += "<a href=\"?" + Preferences.QuerystringParameterName + "=" + searchTermDisplay[i] + "\" title=\"" + searchTermArray[i] + "\">"
+ searchTermDisplay[i]
+ "</a> <font color=gray style='font-size:xx-small'>(" + resultsInThisSet + ")</font> ";
if ((lengthOfShortestResultSet == -1) || (lengthOfShortestResultSet > resultsInThisSet))
{
indexOfShortestResultSet = i;
lengthOfShortestResultSet = resultsInThisSet;
}
}
}
// Find the common files from the array of arrays of documents
// matching ONE of the criteria
if (botherToFindMatches) // all words have *some* matches
{ // for each result set [NOT required, but maybe later if we do AND/OR searches)
int c = indexOfShortestResultSet; // loop through the *shortest* resultset
Dictionary<File, List<int>> searchResultsArray = searchResultsArrayArray[c];
foreach (File foundInFile in searchResultsArray.Keys) // for each file in the *shortest* result set
{
//DictionaryEntry fo = (DictionaryEntry)foundInFile; // find matching files in the other resultsets
int matchcount = 0, totalcount = 0, weight = 0;
List<int> occurences = new List<int>();
for (int cx = 0; cx < searchResultsArrayArray.Length; cx++)
{
totalcount += (cx + 1); // keep track, so we can compare at the end (if term is in ALL resultsets)
if (cx == c) // current resultset
{
matchcount += (cx + 1); // implicitly matches in the current resultset
//weight += (int)fo.Value; // sum the weighting
weight += searchResultsArray[foundInFile].Count; // sum the weighting
occurences.AddRange(searchResultsArray[foundInFile]);
}
else
{
Dictionary<File, List<int>> searchResultsArrayx = searchResultsArrayArray[cx];
if (null != searchResultsArrayx)
{
foreach (File foundInFilex in searchResultsArrayx.Keys)
{ // for each file in the result set
//DictionaryEntry fox = (DictionaryEntry)foundInFilex;
//if (fo.Key == fox.Key)
if (foundInFile == foundInFilex)
{
matchcount += (cx + 1); // and if it matches, track the matchcount
//weight += (int)fox.Value; // and weighting; then break out of loop, since
weight += searchResultsArrayx[foundInFilex].Count;
occurences.AddRange(searchResultsArrayx[foundInFilex]);
break; // no need to keep looking through this resultset
}
} // foreach
} // if
} // else
} // for
if ((matchcount > 0) && (matchcount == totalcount)) // was matched in each Array
{ // we build the finalResults here, to pass to the formatting code below
// - we could do the formatting here, but it would mix up the 'result generation'
// and display code too much
//fo.Value = weight; // set the 'weight' in the combined results to the sum of individual document matches
//if (!finalResultsArray.Contains(fo.Key)) finalResultsArray.Add(fo.Key, fo);
if (!finalResultsArray.Contains(foundInFile)) finalResultsArray.Add(foundInFile, occurences); //.Count
} // if
} // foreach
}
// Time taken calculation
Int64 ticks = DateTime.Now.Ticks - start.Ticks;
TimeSpan taken = new TimeSpan(ticks);
if (taken.Seconds > 0)
{
_DisplayTime = taken.Seconds + " seconds";
}
else if (taken.TotalMilliseconds > 0)
{
_DisplayTime = Convert.ToInt32(taken.TotalMilliseconds) + " milliseconds";
}
else
{
_DisplayTime = "less than 1 millisecond";
}
// The preceding 80 lines (or so) replaces this single line from Version 1
// Hashtable searchResultsArray = m_catalog.Search (searchterm);
// when only single-word-searches were supported. Look closely and you'll see this line
// labelled #THE SEARCH# still in the code above...
// Format the results
if (finalResultsArray.Count > 0)
{ // intermediate data-structure for 'ranked' result HTML
//SortedList
output = new SortedList(finalResultsArray.Count); // empty sorted list
// DictionaryEntry fo;
ResultFile infile;
// string result="";
int sortrank = 0;
// build each result row
foreach (object foundInFile in finalResultsArray.Keys)
{
// Create a ResultFile with it's own Rank
infile = new ResultFile((File)foundInFile);
// [v7] if we have a cache of the page's content, we'll display the relevant
// text excerpt in the search results
if (catalog.FileCache.Contains(infile.Url))
{
string desc = "";
string[] words = catalog.FileCache.GetDocumentCache(infile.Url);
int position = (words.Length / 2); // # find the position of a searched-for word here !!!!!!!
if (words.Length < 10)
{
for (int i = 0; i < words.Length; i++)
{
desc += words[i] + " ";
}
}
else
{
List<int> pos = (List<int>)finalResultsArray[foundInFile];
pos.Sort();
int q = 0;
position = pos[q];
List<int> useablePos = new List<int>();
foreach (int p in pos)
{
if (p < (position + 50)) useablePos.Add(p);
if (p > (position + 50)) break;
}
int lowerBound = (position < 24) ? position : 24;
int upperBound = (position < 24) ? 48 - position : 24;
lowerBound = position - lowerBound;
upperBound = position + upperBound;
if (upperBound > words.Length) upperBound = words.Length - 1;
for (int i = lowerBound; i < upperBound; i++)
{
if (i == position) desc += "<b>";
desc += words[i] + " ";
if (i == position)
{
desc += "</b>";
q++;
if (q < pos.Count) { position = pos[q]; }
}
}
}
infile.Description = desc;
}
if (geolocOnly && (infile.GpsLocation == null || infile.GpsLocation == new Location() ))
{
// don't add this ResultFile to output [v6]
}
else
{
// Jim Harkins [sort for paging] ported from VB to C#
// http://www.codeproject.com/aspnet/spideroo.asp#xx927327xx
//infile.Rank = (int)((DictionaryEntry)finalResultsArray[foundInFile]).Value;
infile.Rank = (int)((List<int>)finalResultsArray[foundInFile]).Count;
sortrank = infile.Rank * -1000; // Assume not 'thousands' of results
if (output.Contains(sortrank))
{ // rank exists - drop key index one number until it fits
for (int i = 1; i < 999; i++)
{
sortrank++;
if (!output.Contains(sortrank))
{
output.Add(sortrank, infile);
if (infile.GpsLocation != null) _GeolocCount += 1;
break;
}
}
}
else
{
output.Add(sortrank, infile);
if (infile.GpsLocation != null) _GeolocCount += 1;
}
}
sortrank = 0; // reset for next pass
}
// Jim Harkins [paged results]
// http://aspnet.4guysfromrolla.com/articles/081804-1.aspx
} // else Count == 0, so output SortedList will be empty
}
}
return output;
}
private void SetPreferences()
{
// Set-up Stemming (if required)
switch (Preferences.StemmingMode)
{
case 1:
_Stemmer = new PorterStemmer(); //Stemmer = new SnowStemming();
break;
case 2:
_Stemmer = new PorterStemmer();
break;
default:
_Stemmer = new NoStemming();
break;
}
switch (Preferences.GoWordMode)
{
case 1:
_GoChecker = new ListGoWord();
break;
default:
_GoChecker = new NoGoWord();
break;
}
}
}
}
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