From c453717998f44a2c8fbb1635a41aca079ec69f41 Mon Sep 17 00:00:00 2001
From: Chris Cameron <chris.cameron@icdsystems.com>
Date: Mon, 17 Feb 2020 21:38:58 -0500
Subject: [PATCH] feat: First attempt at an ANSI to HTML converter

---
 CHANGELOG.md                                  |  1 +
 .../Converters/AnsiToHtmlTest.cs              | 22 ++++++
 ICD.Common.Utils/Converters/AnsiToHtml.cs     | 74 +++++++++++++++++++
 .../ICD.Common.Utils_SimplSharp.csproj        |  1 +
 4 files changed, 98 insertions(+)
 create mode 100644 ICD.Common.Utils.Tests/Converters/AnsiToHtmlTest.cs
 create mode 100644 ICD.Common.Utils/Converters/AnsiToHtml.cs

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2062021..6ef055f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
  - Added public access to GetValues enumeration extension
  - Added extensions for getting JsonReader values as long or ulong
  - Added DateTimeUtils methods for creating DateTimes from epoch seconds or milliseconds
+ - Added AnsiToHtml converter for visualizing ANSI logs
  
 ### Changed
  - Fixed exception trying to get DHCP status of network interfaces on Linux
diff --git a/ICD.Common.Utils.Tests/Converters/AnsiToHtmlTest.cs b/ICD.Common.Utils.Tests/Converters/AnsiToHtmlTest.cs
new file mode 100644
index 0000000..4d14e5a
--- /dev/null
+++ b/ICD.Common.Utils.Tests/Converters/AnsiToHtmlTest.cs
@@ -0,0 +1,22 @@
+using ICD.Common.Utils.Converters;
+using NUnit.Framework;
+
+namespace ICD.Common.Utils.Tests.Converters
+{
+	[TestFixture]
+	public sealed class AnsiToHtmlTest
+	{
+		[TestCase("black\x1b[37mwhite",
+		          @"black<span style=""color:#BBBBBB"">white</span>")]
+		[TestCase("black\x1b[0mblack",
+		          @"blackblack")]
+		[TestCase("black\x1b[37mwhite\x1b[0m",
+		          @"black<span style=""color:#BBBBBB"">white</span>")]
+		[TestCase("\x1b[30mblack\x1b[37mwhite",
+		          @"<span style=""color:#000000"">black<span style=""color:#BBBBBB"">white</span></span>")]
+		public void ConvertTest(string ansi, string expected)
+		{
+			Assert.AreEqual(expected, AnsiToHtml.Convert(ansi));
+		}
+	}
+}
diff --git a/ICD.Common.Utils/Converters/AnsiToHtml.cs b/ICD.Common.Utils/Converters/AnsiToHtml.cs
new file mode 100644
index 0000000..6dac84d
--- /dev/null
+++ b/ICD.Common.Utils/Converters/AnsiToHtml.cs
@@ -0,0 +1,74 @@
+using System;
+using System.Collections.Generic;
+
+namespace ICD.Common.Utils.Converters
+{
+	public static class AnsiToHtml
+	{
+		/// <summary>
+		/// Matches ANSI escape codes, e.g. \x1b[31m and \x1b[30;1m
+		/// </summary>
+		private const string ANSI_PATTERN = "(?'match'\x01b\\[(?'code'[\\d;]+)m)";
+
+		private const string CODE_RESET = "0";
+
+		/// <summary>
+		/// Matches ANSI escape codes to HTML styles.
+		/// Color values are taken from PuTTY.
+		/// </summary>
+		private static readonly Dictionary<string, string> s_Colors =
+			new Dictionary<string, string>
+			{
+				{"30", "color:#000000"}, // Black
+				{"31", "color:#BB0000"}, // Red
+				{"32", "color:#00BB00"}, // Green
+				{"33", "color:#BBBB00"}, // Yellow
+				{"34", "color:#0000BB"}, // Blue
+				{"35", "color:#BB00BB"}, // Magenta
+				{"36", "color:#00BBBB"}, // Cyan
+				{"37", "color:#BBBBBB"}, // White
+
+				{"30;1", "color:#555555"}, // Bright Black
+				{"31;1", "color:#FF5555"}, // Bright Red
+				{"32;1", "color:#55FF55"}, // Bright Green
+				{"33;1", "color:#FFFF55"}, // Bright Yellow
+				{"34;1", "color:#5555FF"}, // Bright Blue
+				{"35;1", "color:#FF55FF"}, // Bright Magenta
+				{"36;1", "color:#55FFFF"}, // Bright Cyan
+				{"37;1", "color:#FFFFFF"}, // Bright White
+			};
+
+		/// <summary>
+		/// Converts the input ansi string into html with color attributes.
+		/// </summary>
+		/// <param name="ansi"></param>
+		/// <returns></returns>
+		public static string Convert(string ansi)
+		{
+			int depth = 0;
+
+			// Hack - Append a reset to close any open spans
+			ansi += "\x1b[0m";
+
+			return RegexUtils.ReplaceGroup(ansi, ANSI_PATTERN, "match", match =>
+			{
+				string code = match.Groups["code"].Value;
+
+				// Reset code - close all of the open spans.
+				if (code == CODE_RESET)
+				{
+					string output = StringUtils.Repeat("</span>", depth);
+					depth = 0;
+					return output;
+				}
+
+				string style;
+				if (!s_Colors.TryGetValue(code, out style))
+					return match.Value;
+
+				depth++;
+				return string.Format("<span style=\"{0}\">", style);
+			});
+		}
+	}
+}
\ No newline at end of file
diff --git a/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj b/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj
index 432936a..bc0cfbb 100644
--- a/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj
+++ b/ICD.Common.Utils/ICD.Common.Utils_SimplSharp.csproj
@@ -86,6 +86,7 @@
     <Compile Include="Comparers\PredicateComparer.cs" />
     <Compile Include="Comparers\SequenceComparer.cs" />
     <Compile Include="ConsoleColor.cs" />
+    <Compile Include="Converters\AnsiToHtml.cs" />
     <Compile Include="DateTimeUtils.cs" />
     <Compile Include="Email\EmailClient.cs" />
     <Compile Include="Email\eMailErrorCode.cs" />