From c2f5583c0e151a5942b463061d999b997a27adf1 Mon Sep 17 00:00:00 2001
From: Alexandros Kritikos <akritikos@outlook.com>
Date: Tue, 16 Feb 2021 12:27:47 +0200
Subject: [PATCH] =?UTF-8?q?=E2=9C=A8=20Adds=20FileInfoToString=20converter?=
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---
 .../Converters/FileInfoToStringConverter.cs   | 59 +++++++++++++++
 .../FileInfoToStringConverter.cs              | 75 +++++++++++++++++++
 2 files changed, 134 insertions(+)
 create mode 100644 src/Configuration.Persistence/Converters/FileInfoToStringConverter.cs
 create mode 100644 tests/Configuration.PersistenceTests/ConverterTests/FileInfoToStringConverter.cs

diff --git a/src/Configuration.Persistence/Converters/FileInfoToStringConverter.cs b/src/Configuration.Persistence/Converters/FileInfoToStringConverter.cs
new file mode 100644
index 0000000..122ab56
--- /dev/null
+++ b/src/Configuration.Persistence/Converters/FileInfoToStringConverter.cs
@@ -0,0 +1,59 @@
+namespace Kritikos.Configuration.Persistence.Converters
+{
+	using System.IO;
+
+	using Microsoft.EntityFrameworkCore.Storage;
+	using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+	/// <summary>
+	/// Converts from <seealso cref="FileInfo"/> to and from string.
+	/// </summary>
+	public class FileInfoToStringConverter : ValueConverter<FileInfo, string>
+	{
+		/// <summary>
+		/// Initializes a new instance of the <seealso cref="FileInfoToStringConverter"/> class.
+		/// </summary>
+		/// <param name="separator">Character used as directory separator in the persistence layer.</param>
+		/// <param name="basePath"><seealso cref="DirectoryInfo"/> used as path base when handling relative paths.</param>
+		/// <param name="mappingHints">
+		/// Hints that can be used by the <see cref="ITypeMappingSource" /> to create data types with appropriate
+		/// facets for the converted data.
+		/// </param>
+		public FileInfoToStringConverter(
+			char separator,
+			FileSystemInfo? basePath = null,
+			ConverterMappingHints? mappingHints = null)
+			: base(
+				v => FromFileInfo(basePath, v, separator),
+				v => FromPath(basePath, v, separator),
+				mappingHints)
+		{
+		}
+
+		private static FileInfo FromPath(FileSystemInfo? basePath, string filePath, char separator)
+		{
+			var path = (basePath == null
+					? filePath
+					: Path.Combine(basePath.FullName, filePath))
+				.Replace(separator, Path.DirectorySeparatorChar);
+
+			return new FileInfo(path);
+		}
+
+		private static string FromFileInfo(FileSystemInfo? basePath, FileSystemInfo file, char separator)
+		{
+			var path = file.FullName;
+			path = basePath != null
+				? path
+					.Replace(basePath?.FullName ?? string.Empty, string.Empty)[1..]
+				: path;
+
+			path = separator != '\\' && Path.DirectorySeparatorChar == '\\' && Path.GetPathRoot(path).Length - 1 > 0
+				? path[(Path.GetPathRoot(path).Length - 1)..]
+				: path;
+			path = path.Replace(Path.DirectorySeparatorChar, separator);
+
+			return path;
+		}
+	}
+}
diff --git a/tests/Configuration.PersistenceTests/ConverterTests/FileInfoToStringConverter.cs b/tests/Configuration.PersistenceTests/ConverterTests/FileInfoToStringConverter.cs
new file mode 100644
index 0000000..3dac06a
--- /dev/null
+++ b/tests/Configuration.PersistenceTests/ConverterTests/FileInfoToStringConverter.cs
@@ -0,0 +1,75 @@
+namespace Kritikos.Configuration.PersistenceTests.ConverterTests
+{
+	using System.IO;
+
+	using FluentAssertions;
+
+	using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+	using Xunit;
+
+	public class FileInfoToStringConverter
+	{
+		private const string WindowsBase = @"C:\Windows\System32";
+		private const string WindowsRelative = @"drivers\etc\hosts";
+
+		private const string WindowsPath = @"C:\Windows\System32\drivers\etc\hosts";
+
+		private const string LinuxBase = @"/srv/http";
+		private const string LinuxRelative = @"root/index.html";
+		private const string LinuxPath = @"/srv/http/root/index.html";
+
+		private static readonly ConverterMappingHints MappingHints = new(unicode: true);
+
+		[Fact]
+		public void Relative_path_windows()
+		{
+			var converter =
+				new Persistence.Converters.FileInfoToStringConverter('\\', new DirectoryInfo(WindowsBase), MappingHints);
+
+			var file = converter.ConvertFromProvider(WindowsRelative) as FileInfo;
+			var foo = converter.ConvertToProvider(file) as string;
+
+			file.FullName.Should().Be(WindowsPath);
+			foo.Should().Be(WindowsRelative);
+		}
+
+		[Fact]
+		public void Absolute_path_windows()
+		{
+			var converter =
+				new Persistence.Converters.FileInfoToStringConverter('\\', mappingHints: MappingHints);
+
+			var file = converter.ConvertFromProvider(WindowsPath) as FileInfo;
+			var foo = converter.ConvertToProvider(file) as string;
+
+			file.FullName.Should().Be(WindowsPath);
+			foo.Should().Be(WindowsPath);
+		}
+
+		[Fact]
+		public void Relative_path_linux()
+		{
+			var converter =
+				new Persistence.Converters.FileInfoToStringConverter('/', new DirectoryInfo(LinuxBase),
+					mappingHints: MappingHints);
+
+			var file = converter.ConvertFromProvider(LinuxRelative) as FileInfo;
+			var foo = converter.ConvertToProvider(file) as string;
+
+			foo.Should().Be(LinuxRelative);
+		}
+
+		[Fact]
+		public void Absolute_path_linux()
+		{
+			var converter =
+				new Persistence.Converters.FileInfoToStringConverter('/', mappingHints: MappingHints);
+
+			var file = converter.ConvertFromProvider(LinuxPath) as FileInfo;
+			var foo = converter.ConvertToProvider(file) as string;
+
+			foo.Should().Be(LinuxPath);
+		}
+	}
+}