From ecf9cf96ddb87df7082a61fbbdcbbfa366e05b95 Mon Sep 17 00:00:00 2001
From: Reinhard Pointner <reinhard.pointner@gmail.com>
Date: Thu, 11 Aug 2016 20:27:18 +0800
Subject: [PATCH] Make sure TimeStampMetric works the same for all epochs

---
 .../net/filebot/similarity/EpisodeMetrics.java  |  7 ++++---
 .../net/filebot/similarity/TimeStampMetric.java | 17 ++++++++++++-----
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/source/net/filebot/similarity/EpisodeMetrics.java b/source/net/filebot/similarity/EpisodeMetrics.java
index e2da2b52..7f076109 100644
--- a/source/net/filebot/similarity/EpisodeMetrics.java
+++ b/source/net/filebot/similarity/EpisodeMetrics.java
@@ -512,13 +512,14 @@ public enum EpisodeMetrics implements SimilarityMetric {
 	}),
 
 	// Match by file last modified and episode release dates
-	TimeStamp(new TimeStampMetric() {
+	TimeStamp(new TimeStampMetric(10, ChronoUnit.YEARS) {
 
 		@Override
 		public float getSimilarity(Object o1, Object o2) {
-			// adjust differentiation accuracy to about 3 years
+			// adjust differentiation accuracy to about 2.5 years
 			float f = super.getSimilarity(o1, o2);
-			return f >= 0.9 ? 1 : f >= 0 ? 0 : -1;
+
+			return f >= 0.75 ? 1 : f >= 0 ? 0 : -1;
 		}
 
 		private long getTimeStamp(SimpleDate date) {
diff --git a/source/net/filebot/similarity/TimeStampMetric.java b/source/net/filebot/similarity/TimeStampMetric.java
index deac557f..96c18eb7 100644
--- a/source/net/filebot/similarity/TimeStampMetric.java
+++ b/source/net/filebot/similarity/TimeStampMetric.java
@@ -4,21 +4,28 @@ package net.filebot.similarity;
 import java.io.File;
 import java.nio.file.Files;
 import java.nio.file.attribute.BasicFileAttributes;
+import java.time.temporal.ChronoUnit;
 
 public class TimeStampMetric implements SimilarityMetric {
 
+	private long epoch;
+
+	public TimeStampMetric(int i, ChronoUnit unit) {
+		this.epoch = unit.getDuration().multipliedBy(i).toMillis();
+	}
+
 	@Override
 	public float getSimilarity(Object o1, Object o2) {
 		long t1 = getTimeStamp(o1);
 		long t2 = getTimeStamp(o2);
 
-		if (t1 <= 0 || t2 <= 0)
-			return -1;
+		if (t1 > 0 && t2 > 0) {
+			float delta = Math.abs(t1 - t2);
 
-		float min = Math.min(t1, t2);
-		float max = Math.max(t1, t2);
+			return delta > epoch ? 1 : 1 - (delta / epoch);
+		}
 
-		return min / max;
+		return -1;
 	}
 
 	public long getTimeStamp(Object object) {