From be6dc557a3b819248b014992eb96c1cb21f8112b Mon Sep 17 00:00:00 2001
From: vnugent <public@vaughnnugent.com>
Date: Sun, 8 Jan 2023 14:44:01 -0500
Subject: Initial commit

---
 Plugins.Essentials/src/TimestampedCounter.cs | 117 +++++++++++++++++++++++++++
 1 file changed, 117 insertions(+)
 create mode 100644 Plugins.Essentials/src/TimestampedCounter.cs

(limited to 'Plugins.Essentials/src/TimestampedCounter.cs')

diff --git a/Plugins.Essentials/src/TimestampedCounter.cs b/Plugins.Essentials/src/TimestampedCounter.cs
new file mode 100644
index 0000000..19cb8ec
--- /dev/null
+++ b/Plugins.Essentials/src/TimestampedCounter.cs
@@ -0,0 +1,117 @@
+/*
+* Copyright (c) 2022 Vaughn Nugent
+* 
+* Library: VNLib
+* Package: VNLib.Plugins.Essentials
+* File: TimestampedCounter.cs 
+*
+* TimestampedCounter.cs is part of VNLib.Plugins.Essentials which is part of the larger 
+* VNLib collection of libraries and utilities.
+*
+* VNLib.Plugins.Essentials is free software: you can redistribute it and/or modify 
+* it under the terms of the GNU Affero General Public License as 
+* published by the Free Software Foundation, either version 3 of the
+* License, or (at your option) any later version.
+*
+* VNLib.Plugins.Essentials is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU Affero General Public License for more details.
+*
+* You should have received a copy of the GNU Affero General Public License
+* along with this program.  If not, see https://www.gnu.org/licenses/.
+*/
+
+using System;
+
+
+#nullable enable
+
+namespace VNLib.Plugins.Essentials
+{
+    /// <summary>
+    /// Stucture that allows for convient storage of a counter value
+    /// and a second precision timestamp into a 64-bit unsigned integer
+    /// </summary>
+    public readonly struct TimestampedCounter : IEquatable<TimestampedCounter>
+    {
+        /// <summary>
+        /// The time the count was last modifed
+        /// </summary>
+        public readonly DateTimeOffset LastModified;
+        /// <summary>
+        /// The last failed login attempt count value
+        /// </summary>
+        public readonly uint Count;
+
+        /// <summary>
+        /// Initalizes a new flc structure with the current UTC date
+        /// and the specified count value
+        /// </summary>
+        /// <param name="count">FLC current count</param>
+        public TimestampedCounter(uint count) : this(DateTimeOffset.UtcNow, count)
+        { }
+
+        private TimestampedCounter(DateTimeOffset dto, uint count)
+        {
+            Count = count;
+            LastModified = dto;
+        }
+
+        /// <summary>
+        /// Compacts and converts the counter value and timestamp into
+        /// a 64bit unsigned integer
+        /// </summary>
+        /// <param name="count">The counter to convert</param>
+        public static explicit operator ulong(TimestampedCounter count) => count.ToUInt64();
+
+        /// <summary>
+        /// Compacts and converts the counter value and timestamp into
+        /// a 64bit unsigned integer
+        /// </summary>
+        /// <returns>The uint64 compacted value</returns>
+        public ulong ToUInt64()
+        {
+            //Upper 32 bits time, lower 32 bits count
+            ulong value = (ulong)LastModified.ToUnixTimeSeconds() << 32;
+            value |= Count;
+            return value;
+        }
+
+        /// <summary>
+        /// The previously compacted <see cref="TimestampedCounter"/> 
+        /// value to cast back to a counter
+        /// </summary>
+        /// <param name="value"></param>
+        public static explicit operator TimestampedCounter(ulong value) => FromUInt64(value);
+      
+        ///<inheritdoc/>
+        public override bool Equals(object? obj) => obj is TimestampedCounter counter && Equals(counter);
+        ///<inheritdoc/>
+        public override int GetHashCode() => this.ToUInt64().GetHashCode();
+        ///<inheritdoc/>
+        public static bool operator ==(TimestampedCounter left, TimestampedCounter right) => left.Equals(right);
+        ///<inheritdoc/>
+        public static bool operator !=(TimestampedCounter left, TimestampedCounter right) => !(left == right);
+        ///<inheritdoc/>
+        public bool Equals(TimestampedCounter other) => ToUInt64() == other.ToUInt64();
+
+        /// <summary>
+        /// The previously compacted <see cref="TimestampedCounter"/> 
+        /// value to cast back to a counter
+        /// </summary>
+        /// <param name="value">The uint64 encoded <see cref="TimestampedCounter"/></param>
+        /// <returns>
+        /// The decoded <see cref="TimestampedCounter"/> from its 
+        /// compatcted representation
+        /// </returns>
+        public static TimestampedCounter FromUInt64(ulong value)
+        {
+            //Upper 32 bits time, lower 32 bits count
+            long time = (long)(value >> 32);
+            uint count = (uint)(value & uint.MaxValue);
+            //Init dto struct
+            return new(DateTimeOffset.FromUnixTimeSeconds(time), count);
+        }
+    }
+}
\ No newline at end of file
-- 
cgit