From 1803b9fef9fe055b7125f91d8dc63734c18675cb Mon Sep 17 00:00:00 2001
From: FICTURE7 <ficture7@gmail.com>
Date: Fri, 9 Apr 2021 20:52:28 +0400
Subject: [PATCH] Add Counter

---
 ARMeilleure/Common/Counter.cs | 48 +++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 ARMeilleure/Common/Counter.cs

diff --git a/ARMeilleure/Common/Counter.cs b/ARMeilleure/Common/Counter.cs
new file mode 100644
index 000000000..d3d28730e
--- /dev/null
+++ b/ARMeilleure/Common/Counter.cs
@@ -0,0 +1,48 @@
+namespace ARMeilleure.Common
+{
+    /// <summary>
+    /// Represents an 8-bit counter.
+    /// </summary>
+    class Counter
+    {
+        private readonly int _index;
+        private readonly EntryTable<byte> _countTable;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Counter"/> class from the specified
+        /// <see cref="EntryTable{byte}"/> instance and index.
+        /// </summary>
+        /// <param name="countTable"><see cref="EntryTable{byte}"/> instance</param>
+        /// <param name="index">Index in the <see cref="EntryTable{TEntry}"/></param>
+        private Counter(EntryTable<byte> countTable, int index)
+        {
+            _countTable = countTable;
+            _index = index;
+        }
+
+        /// <summary>
+        /// Gets a reference to the value of the counter.
+        /// </summary>
+        public ref byte Value => ref _countTable.GetValue(_index);
+
+        /// <summary>
+        /// Tries to create a <see cref="Counter"/> instance from the specified <see cref="EntryTable{byte}"/> instance.
+        /// </summary>
+        /// <param name="countTable"><see cref="EntryTable{TEntry}"/> from which to create the <see cref="Counter"/></param>
+        /// <param name="counter"><see cref="Counter"/> instance if success; otherwise <see langword="null"/></param>
+        /// <returns><see langword="true"/> if success; otherwise <see langword="false"/></returns>
+        public static bool TryCreate(EntryTable<byte> countTable, out Counter counter)
+        {
+            if (countTable.TryAllocate(out int index))
+            {
+                counter = new Counter(countTable, index);
+
+                return true;
+            }
+
+            counter = null;
+
+            return false;
+        }
+    }
+}
\ No newline at end of file