From 9768728c925cde44d527c1adca7e68e1369790c7 Mon Sep 17 00:00:00 2001
From: James Seibel <jeseibel@gondtc.com>
Date: Sat, 31 Aug 2024 14:58:08 -0500
Subject: [PATCH] Add RollingAverage object

---
 .../core/util/objects/RollingAverage.java     | 111 ++++++++++++++++++
 1 file changed, 111 insertions(+)
 create mode 100644 core/src/main/java/com/seibel/distanthorizons/core/util/objects/RollingAverage.java

diff --git a/core/src/main/java/com/seibel/distanthorizons/core/util/objects/RollingAverage.java b/core/src/main/java/com/seibel/distanthorizons/core/util/objects/RollingAverage.java
new file mode 100644
index 000000000..366ee40bc
--- /dev/null
+++ b/core/src/main/java/com/seibel/distanthorizons/core/util/objects/RollingAverage.java
@@ -0,0 +1,111 @@
+package com.seibel.distanthorizons.core.util.objects;
+
+import java.util.Arrays;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+/**
+ * This can be used for easily profiling methods to get the average execution time. <br>
+ * This is a thread safe implementation. 
+ */
+public class RollingAverage
+{
+	// properties //
+	
+	private final double[] values;
+	private final int size;
+	private int index = 0;
+	private double sum = 0.0;
+	private final Lock arrayLock = new ReentrantLock();
+	
+	
+	
+	//=============//
+	// constructor //
+	//=============//
+	
+	public RollingAverage(int size)
+	{
+		if (size <= 0)
+		{
+			throw new IllegalArgumentException("Size must be greater than 0");
+		}
+		
+		this.size = size;
+		this.values = new double[size];
+	}
+	
+	
+	
+	//=======//
+	// input //
+	//=======//
+	
+	public void addValue(double value)
+	{
+		this.arrayLock.lock();
+		try
+		{
+			// Subtract the oldest value from the sum
+			this.sum -= this.values[this.index];
+			// Update the buffer with the new value
+			this.values[this.index] = value;
+			// Add the new value to the sum
+			this.sum += value;
+			// Move to the next index
+			this.index = (this.index + 1) % this.size;
+		}
+		finally
+		{
+			this.arrayLock.unlock();
+		}
+	}
+	
+	public void clear()
+	{
+		this.arrayLock.lock();
+		try
+		{
+			this.sum = 0;
+			this.index = 0;
+			Arrays.fill(this.values, 0);
+		}
+		finally
+		{
+			this.arrayLock.unlock();
+		}
+	}
+	
+	
+	
+	//========//
+	// output //
+	//========//
+	
+	/** Gets the current rolling average. */
+	public double getAverage()
+	{
+		this.arrayLock.lock();
+		try
+		{
+			return (this.sum / this.size);
+		}
+		finally
+		{
+			this.arrayLock.unlock();
+		}
+	}
+	/** rounded to two decimals*/
+	public String getAverageRoundedString() { return String.format("%.2f", this.getAverage()); }
+	
+	
+	
+	//================//
+	// base overrides //
+	//================//
+	
+	@Override 
+	public String toString() { return "avg: "+this.getAverageRoundedString()+" max count: "+this.size; }
+	
+}
+