Imported Upstream version 5.2.0.179

Former-commit-id: a536d4f20e27294d8bbc2184d75f3a22364f7ba1

external/api-doc-tools/monodoc/Monodoc/SearchableIndex.cs

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+//
+//
+// SearchableIndex.cs: Index that uses Lucene to search through the docs 
+//
+// Author: Mario Sopena
+//
+
+using System;
+using System.IO;
+using System.Collections.Generic;
+// Lucene imports
+using Lucene.Net.Index;
+using Lucene.Net.Documents;
+using Lucene.Net.Analysis;
+using Lucene.Net.Analysis.Standard;
+using Lucene.Net.Search;
+using Lucene.Net.QueryParsers;
+using Lucene.Net.Store;
+
+namespace Monodoc
+{
+	public class SearchableIndex 
+	{
+		const int maxSearchCount = 30;
+
+		IndexSearcher searcher;
+		string dir;
+
+		public string Dir {
+			get { 
+				if (dir == null)
+					dir = "search_index";
+				return dir;
+			}
+			set { dir = value; }
+		}
+
+		public static SearchableIndex Load (string dir)
+		{
+			SearchableIndex s = new SearchableIndex ();
+			s.dir = dir;
+			try {
+				//s.searcher = new IndexSearcher (dir);
+				// TODO: parametrize that depending if we run on the desktop (low footprint) or the server (use RAMDirectory for instance)
+				s.searcher = new IndexSearcher (FSDirectory.Open (dir));
+			} catch (IOException) {
+				Console.WriteLine ("Index nonexistent or in bad format");
+				return null;
+			}
+			return s;
+		}
+		
+		public Result Search (string term)
+		{
+			return Search (term, maxSearchCount);
+		}
+
+		public Result Search (string term, int count)
+		{
+			return Search (term, count, 0);
+		}
+
+		public Result Search (string term, int count, int start) {
+			try {
+				term = term.ToLower ();
+				Term htTerm = new Term ("hottext", term);
+				Query qq1 = new FuzzyQuery (htTerm);
+				Query qq2 = new TermQuery (htTerm);
+				qq2.Boost = 10f;
+				Query qq3 = new PrefixQuery (htTerm);
+				qq3.Boost = 10f;
+				DisjunctionMaxQuery q1 = new DisjunctionMaxQuery (0f);
+				q1.Add (qq1);
+				q1.Add (qq2);
+				q1.Add (qq3);
+				Query q2 = new TermQuery (new Term ("text", term));
+				q2.Boost = 3f;
+				Query q3 = new TermQuery (new Term ("examples", term));
+				q3.Boost = 3f;
+				DisjunctionMaxQuery q = new DisjunctionMaxQuery (0f);
+
+				q.Add (q1);
+				q.Add (q2);
+				q.Add (q3);
+			
+				TopDocs top = SearchInternal (q, count, start);
+				Result r = new Result (term, searcher, top.ScoreDocs);
+				return r;
+			} catch (IOException) {
+				Console.WriteLine ("No index in {0}", dir);
+				return null;
+			}
+		}
+
+		TopDocs SearchInternal (Query q, int count, int start)
+		{
+			// Easy path that doesn't involve creating a Collector ourselves
+			// watch for Lucene.NET improvement on that (like searcher.SearchAfter)
+			if (start == 0)
+				return searcher.Search (q, count);
+
+			var weight = searcher.CreateWeight (q); // TODO: reuse weight instead of query
+			var collector = TopScoreDocCollector.Create (start + count + 1, false);
+			searcher.Search (q, collector);
+
+			return collector.TopDocs (start, count);
+		}
+
+		public Result FastSearch (string term, int number)
+		{
+			try {
+				term = term.ToLower ();
+				Query q1 = new TermQuery (new Term ("hottext", term));
+				Query q2 = new PrefixQuery (new Term ("hottext", term));
+				q2.Boost = 0.5f;
+				DisjunctionMaxQuery q = new DisjunctionMaxQuery (0f);
+				q.Add (q1);
+				q.Add (q2);
+				TopDocs top = searcher.Search (q, number);
+				return new Result (term, searcher, top.ScoreDocs);
+			} catch (IOException) {
+				Console.WriteLine ("No index in {0}", dir);
+				return null;
+			}
+		}
+	}
+
+	//
+	// An object representing the search term with the results
+	// 
+	public class Result {
+		string term;
+		Searcher searcher;
+		ScoreDoc[] docs;
+
+		public string Term {
+			get { return term;}
+		}
+
+		public int Count {
+			get { return docs.Length; }
+		}
+
+		public Document this [int i] {
+			get { return searcher.Doc (docs[i].Doc); }
+		}
+	
+		public string GetTitle (int i) 
+		{
+			Document d = this[i];
+			return d == null ? string.Empty : d.Get ("title");
+		}
+
+		public string GetUrl (int i)
+		{
+			Document d = this[i];
+			return d == null ? string.Empty : d.Get ("url");
+		}
+
+		public string GetFullTitle (int i)
+		{
+			Document d = this[i];
+			return d == null ? string.Empty : d.Get ("fulltitle");
+		}
+
+		public float Score (int i)
+		{
+			return docs[i].Score;
+		}
+
+		public Result (string Term, Searcher searcher, ScoreDoc[] docs) 
+		{
+			this.term = Term;
+			this.searcher = searcher;
+			this.docs = docs;
+		}
+	}
+}
+