From 8759d9a5f7e33303810ba50ad97746983d5b7d38 Mon Sep 17 00:00:00 2001
From: =?utf8?q?David=20=E2=80=98Bombe=E2=80=99=20Roden?=
 <bombe@pterodactylus.net>
Date: Fri, 15 Apr 2011 06:19:44 +0200
Subject: [PATCH] Use double instead of int for score calculation, weigh
 position of hit more.

---
 .../net/pterodactylus/sone/web/SearchPage.java     | 23 ++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/main/java/net/pterodactylus/sone/web/SearchPage.java b/src/main/java/net/pterodactylus/sone/web/SearchPage.java
index 1d1aa36..903975d 100644
--- a/src/main/java/net/pterodactylus/sone/web/SearchPage.java
+++ b/src/main/java/net/pterodactylus/sone/web/SearchPage.java
@@ -35,6 +35,7 @@ import net.pterodactylus.util.collection.Converters;
 import net.pterodactylus.util.collection.Pagination;
 import net.pterodactylus.util.filter.Filter;
 import net.pterodactylus.util.filter.Filters;
+import net.pterodactylus.util.logging.Logging;
 import net.pterodactylus.util.number.Numbers;
 import net.pterodactylus.util.template.Template;
 import net.pterodactylus.util.template.TemplateContext;
@@ -137,7 +138,7 @@ public class SearchPage extends SoneTemplatePage {
 		Set<Hit<T>> hits = new HashSet<Hit<T>>();
 		for (T object : objects) {
 			String objectString = stringGenerator.generateString(object);
-			int score = calculateScore(phrases, objectString);
+			double score = calculateScore(phrases, objectString);
 			hits.add(new Hit<T>(object, score));
 		}
 		return hits;
@@ -185,9 +186,9 @@ public class SearchPage extends SoneTemplatePage {
 	 *            The expression to search
 	 * @return The score of the expression
 	 */
-	private int calculateScore(List<Phrase> phrases, String expression) {
-		int optionalHits = 0;
-		int requiredHits = 0;
+	private double calculateScore(List<Phrase> phrases, String expression) {
+		double optionalHits = 0;
+		double requiredHits = 0;
 		int forbiddenHits = 0;
 		int requiredPhrases = 0;
 		for (Phrase phrase : phrases) {
@@ -197,11 +198,13 @@ public class SearchPage extends SoneTemplatePage {
 			}
 			int matches = 0;
 			int index = 0;
+			double score = 0;
 			while (index < expression.length()) {
 				int position = expression.toLowerCase().indexOf(phraseString, index);
 				if (position == -1) {
 					break;
 				}
+				score += Math.pow(1 - position / (double) expression.length(), 2);
 				index = position + phraseString.length();
 				++matches;
 			}
@@ -209,10 +212,10 @@ public class SearchPage extends SoneTemplatePage {
 				continue;
 			}
 			if (phrase.getOptionality() == Phrase.Optionality.REQUIRED) {
-				requiredHits += matches;
+				requiredHits += score;
 			}
 			if (phrase.getOptionality() == Phrase.Optionality.OPTIONAL) {
-				optionalHits += matches;
+				optionalHits += score;
 			}
 			if (phrase.getOptionality() == Phrase.Optionality.FORBIDDEN) {
 				forbiddenHits += matches;
@@ -418,7 +421,7 @@ public class SearchPage extends SoneTemplatePage {
 
 			@Override
 			public int compare(Hit<?> leftHit, Hit<?> rightHit) {
-				return rightHit.getScore() - leftHit.getScore();
+				return (rightHit.getScore() < leftHit.getScore()) ? -1 : ((rightHit.getScore() > leftHit.getScore()) ? 1 : 0);
 			}
 
 		};
@@ -427,7 +430,7 @@ public class SearchPage extends SoneTemplatePage {
 		private final T object;
 
 		/** The score of the object. */
-		private final int score;
+		private final double score;
 
 		/**
 		 * Creates a new hit.
@@ -437,7 +440,7 @@ public class SearchPage extends SoneTemplatePage {
 		 * @param score
 		 *            The score of the object
 		 */
-		public Hit(T object, int score) {
+		public Hit(T object, double score) {
 			this.object = object;
 			this.score = score;
 		}
@@ -456,7 +459,7 @@ public class SearchPage extends SoneTemplatePage {
 		 *
 		 * @return The score of the object
 		 */
-		public int getScore() {
+		public double getScore() {
 			return score;
 		}
 
-- 
2.7.4