Counter.cs

using System;
using System.Collections.Generic;
using System.Linq;

namespace NG.Diagnostics
{
    /// <summary>
    /// A diagnostic counter that maintains the Min, Max, and Average counts fed in to it.
    /// </summary>
    public class Counter
    {
        private List<int> values = new List<int>();
        private List<KeyValuePair<int, int>> sumCountsPairs = new List<KeyValuePair<int, int>>();
        private int bufferSize = int.MaxValue - 1;

        /// <summary>
        /// The maximum count.
        /// </summary>
        public int Max { get; private set; }

        /// <summary>
        /// The minimum count.
        /// </summary>
        public int Min { get; private set; }


        /// <summary>
        /// The average count.
        /// </summary>
        public int Average
        {
            get
            {
                long count = (long)values.Count;

                long sum = 0;
                if (count > 0)
                    sum = values.Sum();

                foreach (var item in sumCountsPairs)
                {
                    long maxCheck = long.MaxValue - count;
                    if ((uint)item.Value < maxCheck)
                        count += (uint)item.Value;
                    else
                        break;
                    sum += item.Key;
                }

                if (count > 0)
                    return (int)(sum / count);
                else
                    return 0;
            }
        }

        /// <summary>
        /// The last count added to this counter.
        /// </summary>
        public int Last
        {
            get
            {
                if (values.Count > 0)
                    return values.Last();
                else
                    return -1;
            }
        }

        public long Sum { get; private set; }

        /// <summary>
        /// Constructor ensures initial values for Min and Max.
        /// </summary>
        public Counter()
        {
            Max = int.MinValue;
            Min = int.MaxValue;
        }


        /// <summary>
        /// Call this to capture a count.
        /// </summary>
        /// <param name="value">The count to record.</param>
        /// <param name="shouldCaptureZero">Should this capture a count of zero? Default is false.</param>
        public void Record(int value, bool shouldCaptureZero = false)
        {
            if (!shouldCaptureZero && value == 0)
                return;

            Max = Math.Max(value, Max);
            Min = Math.Min(value, Min);

            if (values.Count >= bufferSize)
            {
                sumCountsPairs.Add(new KeyValuePair<int, int>(values.Sum(), values.Count));
                values.Clear();
            }

            values.Add(value);
            Sum += value;
        }
    }
}