From 110f771cc53cc838fde51613f2248b1497816ccb Mon Sep 17 00:00:00 2001
From: Chris Cameron <chris.cameron@wedoresi.com>
Date: Wed, 9 May 2018 11:35:53 -0400
Subject: [PATCH] feat: Added util method for removing BOM characters from UTF8
 data

---
 CHANGELOG.md                                  |  1 +
 ICD.Common.Utils.Tests/EncodingUtilsTest.cs   | 23 ++++++++++++++
 ICD.Common.Utils/EncodingUtils.cs             | 30 +++++++++++++++++++
 .../ICD.Common.Utils_SimplSharp.csproj        |  1 +
 4 files changed, 55 insertions(+)
 create mode 100644 ICD.Common.Utils.Tests/EncodingUtilsTest.cs
 create mode 100644 ICD.Common.Utils/EncodingUtils.cs

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 165e567..0aa9c06 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
  - Added Yield extension to return a single-item enumerable for an object.
+ - Added util method for removing BOM characters from UTF8 data
 
 ## [3.0.0] - 2018-04-23
 ### Added
diff --git a/ICD.Common.Utils.Tests/EncodingUtilsTest.cs b/ICD.Common.Utils.Tests/EncodingUtilsTest.cs
new file mode 100644
index 0000000..33bc129
--- /dev/null
+++ b/ICD.Common.Utils.Tests/EncodingUtilsTest.cs
@@ -0,0 +1,23 @@
+using System;
+using System.Text;
+using NUnit.Framework;
+
+namespace ICD.Common.Utils.Tests
+{
+	[TestFixture]
+	public sealed class EncodingUtilsTest
+	{
+		[Test]
+		public void StripUtf8BomTest()
+		{
+			Assert.Throws<ArgumentNullException>(() => EncodingUtils.StripUtf8Bom(null));
+
+			byte[] preamble = Encoding.UTF8.GetPreamble();
+			string preambleString = Encoding.UTF8.GetString(preamble, 0, preamble.Length);
+
+			Assert.AreEqual(string.Empty, EncodingUtils.StripUtf8Bom(string.Empty));
+			Assert.AreEqual("test", EncodingUtils.StripUtf8Bom("test"));
+			Assert.AreEqual("test", EncodingUtils.StripUtf8Bom(preambleString + "test"));
+		}
+	}
+}
diff --git a/ICD.Common.Utils/EncodingUtils.cs b/ICD.Common.Utils/EncodingUtils.cs
new file mode 100644
index 0000000..e1f45cc
--- /dev/null
+++ b/ICD.Common.Utils/EncodingUtils.cs
@@ -0,0 +1,30 @@
+using System;
+using System.Text;
+using ICD.Common.Properties;
+
+namespace ICD.Common.Utils
+{
+	public static class EncodingUtils
+	{
+		/// <summary>
+		/// Strips leading Byte Order Mark characters from the given UTF8 data.
+		/// </summary>
+		/// <param name="data">Input string to remove leading BOM chars from.</param>
+		/// <returns>Input string with leading BOM chars removed.</returns>
+		/// <exception cref="ArgumentNullException">Data is null.</exception>
+		[PublicAPI]
+		public static string StripUtf8Bom(string data)
+		{
+			if (data == null)
+				throw new ArgumentNullException("data");
+
+			byte[] preamble = Encoding.UTF8.GetPreamble();
+			string preambleString = Encoding.UTF8.GetString(preamble, 0, preamble.Length);
+
+			if (data.StartsWith(preambleString, StringComparison.Ordinal))
+				data = data.Remove(0, preambleString.Length);
+
+			return data;
+		}
+	}
+}
diff --git a/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj b/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj
index 231f2aa..ece69a3 100644
--- a/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj
+++ b/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj
@@ -77,6 +77,7 @@
     <Compile Include="Collections\WeakKeyDictionary.cs" />
     <Compile Include="Comparers\PredicateComparer.cs" />
     <Compile Include="ConsoleColor.cs" />
+    <Compile Include="EncodingUtils.cs" />
     <Compile Include="EventArguments\BoolEventArgs.cs" />
     <Compile Include="EventArguments\CharEventArgs.cs" />
     <Compile Include="EventArguments\DateTimeEventArgs.cs" />