From 0d6c7191481c4ecc9f8861f67f92f01583966c32 Mon Sep 17 00:00:00 2001
From: Thorsten Sommer <mail@tsommer.org>
Date: Tue, 4 Aug 2020 20:51:13 +0200
Subject: [PATCH] Implemented store and load methods

---
 ExaArray/ExaArray1D.cs           | 65 +++++++++++++++++++++++++++++++-
 ExaArrayTests/ExaArray1DTests.cs | 59 +++++++++++++++++++++++++++++
 2 files changed, 123 insertions(+), 1 deletion(-)

diff --git a/ExaArray/ExaArray1D.cs b/ExaArray/ExaArray1D.cs
index 94f9e23..c837fbf 100644
--- a/ExaArray/ExaArray1D.cs
+++ b/ExaArray/ExaArray1D.cs
@@ -1,5 +1,8 @@
 using System;
 using System.Collections.Generic;
+using System.IO;
+using System.Runtime.Serialization;
+using System.Runtime.Serialization.Formatters.Binary;
 
 namespace Exa
 {
@@ -8,7 +11,8 @@ namespace Exa
     /// to 4.6 quintillion (4,607,183,514,018,780,000) or 4.6 exa elements. 
     /// </summary>
     /// <typeparam name="T">The desired type to use, e.g. byte, int, etc.</typeparam>
-    public sealed partial class ExaArray1D<T>
+    [Serializable]
+    public sealed partial class ExaArray1D<T> : ISerializable
     {
         /// <summary>
         /// Unfortunately, this seems to be the maximal number of entries an
@@ -218,5 +222,64 @@ namespace Exa
             for (ulong n = 0; n < this.Length; n++)
                 yield return this[n];
         }
+
+        #region Store and load
+
+        /// <summary>
+        /// Stores the exa array into a stream.
+        /// </summary>
+        /// <remarks>
+        /// This method does not dispose the stream.
+        /// </remarks>
+        public void Store(Stream outputStream)
+        {
+            var formatter = new BinaryFormatter();
+            formatter.Serialize(outputStream, this);
+        }
+
+        /// <summary>
+        /// Restores an exa array from the given stream.
+        /// </summary>
+        /// <remarks>
+        /// This method does not dispose the stream.
+        /// </remarks>
+        public static ExaArray1D<T> Restore(Stream inputStream)
+        {
+            var formatter = new BinaryFormatter();
+            return formatter.Deserialize(inputStream) as ExaArray1D<T>;
+        }
+
+        #endregion
+
+        #region Serialization
+
+        /// <summary>
+        /// This method serves for the serialization process. Do not call it manually. 
+        /// </summary>
+        public void GetObjectData(SerializationInfo info, StreamingContext context)
+        {
+            info.AddValue("version", "v1");
+            info.AddValue("strategy", this.OptimizationStrategy, typeof(Strategy));
+            info.AddValue("length", this.Length);
+            info.AddValue("chunks", this.chunks, typeof(T[][]));
+        }
+        
+        private ExaArray1D(SerializationInfo info, StreamingContext context)
+        {
+            switch (info.GetString("version"))
+            {
+                case "v1":
+                    this.Length = info.GetUInt64("length");
+                    this.chunks = info.GetValue("chunks", typeof(T[][])) as T[][];
+                    this.OptimizationStrategy = (Strategy) info.GetValue("strategy", typeof(Strategy));
+                    break;
+            }
+
+            this.chunks[0] ??= new T[0];
+            this.maxElements = this.OptimizationStrategy == Strategy.MAX_PERFORMANCE ? MAX_NUMBER_ELEMENTS_PERFORMANCE : MAX_NUMBER_ELEMENTS;
+            this.maxArrayCapacity = this.OptimizationStrategy == Strategy.MAX_PERFORMANCE ? MAX_CAPACITY_ARRAY_PERFORMANCE : MAX_CAPACITY_ARRAY;
+        }
+
+        #endregion
     }
 }
\ No newline at end of file
diff --git a/ExaArrayTests/ExaArray1DTests.cs b/ExaArrayTests/ExaArray1DTests.cs
index 11d02fd..57c75e0 100644
--- a/ExaArrayTests/ExaArray1DTests.cs
+++ b/ExaArrayTests/ExaArray1DTests.cs
@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
+using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
 using Exa;
@@ -12,6 +13,7 @@ namespace ExaArrayTests
     [ExcludeFromCodeCoverage]
     public class ExaArray1DTests
     {
+        [Serializable]
         private class TestClass
         {
             public int Age { get; set; }
@@ -734,5 +736,62 @@ namespace ExaArrayTests
 
             TestContext.WriteLine($"Performing 100M assignments took {t2Times.Average()} ms (average) by means of the max. performance strategy (min={t2Times.Min()} ms, max={t2Times.Max()} ms)");
         }
+        
+        [Test]
+        [Category("cover")]
+        [Category("normal")]
+        public void StoreAndLoad01()
+        {
+            var exaA = new ExaArray1D<byte>();
+            exaA.Extend(5_000_000);
+            exaA[4_483_124] = 0xff;
+
+            var filename = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
+            using (var file = File.OpenWrite(filename))
+            {
+                exaA.Store(file);
+            }
+
+            using (var file = File.OpenRead(filename))
+            {
+                var exaB = ExaArray1D<byte>.Restore(file);
+                
+                Assert.That(exaA.Length, Is.EqualTo(exaB.Length));
+                Assert.That(exaA[4_483_124], Is.EqualTo(0xff));
+                Assert.That(exaB[4_483_124], Is.EqualTo(0xff));
+            }
+            
+            File.Delete(filename);
+        }
+        
+        [Test]
+        [Category("cover")]
+        [Category("normal")]
+        public void StoreAndLoad02()
+        {
+            var exaA = new ExaArray1D<TestClass>();
+            exaA.Extend(100);
+            exaA[66] = new TestClass
+            {
+                Age = 55,
+            };
+
+            var filename = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
+            using (var file = File.OpenWrite(filename))
+            {
+                exaA.Store(file);
+            }
+
+            using (var file = File.OpenRead(filename))
+            {
+                var exaB = ExaArray1D<TestClass>.Restore(file);
+                
+                Assert.That(exaA.Length, Is.EqualTo(exaB.Length));
+                Assert.That(exaA[66].Age, Is.EqualTo(55));
+                Assert.That(exaB[66].Age, Is.EqualTo(55));
+            }
+            
+            File.Delete(filename);
+        }
     }
 }
\ No newline at end of file