Refactor valid path/filename. Centralize validaion. Universal templating is one step closer

FileManager.Tests/FileTemplateTests.cs

@@ -0,0 +1,108 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using Dinah.Core;
+using FileManager;
+using FluentAssertions;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace FileTemplateTests
+{
+	[TestClass]
+	public class GetFilename
+	{
+		[TestMethod]
+		public void equiv_GetValidFilename()
+		{
+			var expected = @"C:\foo\bar\my_ book LONG_1234567890_1234567890_1234567890_123 [ID123456].txt";
+			var f1 = OLD_GetValidFilename(@"C:\foo\bar", "my: book LONG_1234567890_1234567890_1234567890_12345", "txt", "ID123456");
+			var f2 = NEW_GetValidFilename_FileTemplate(@"C:\foo\bar", "my: book LONG_1234567890_1234567890_1234567890_12345", "txt", "ID123456");
+
+			f1.Should().Be(expected);
+			f1.Should().Be(f2);
+		}
+		private static string OLD_GetValidFilename(string dirFullPath, string filename, string extension, string metadataSuffix)
+		{
+			ArgumentValidator.EnsureNotNullOrWhiteSpace(dirFullPath, nameof(dirFullPath));
+
+			filename ??= "";
+
+			// sanitize. omit invalid characters. exception: colon => underscore
+			filename = filename.Replace(":", "_");
+			filename = FileUtility.GetSafeFileName(filename);
+
+			if (filename.Length > 50)
+				filename = filename.Substring(0, 50);
+
+			if (!string.IsNullOrWhiteSpace(metadataSuffix))
+				filename += $" [{metadataSuffix}]";
+
+			// extension is null when this method is used for directory names
+			extension = FileUtility.GetStandardizedExtension(extension);
+
+			// ensure uniqueness
+			var fullfilename = Path.Combine(dirFullPath, filename + extension);
+			var i = 0;
+			while (File.Exists(fullfilename))
+				fullfilename = Path.Combine(dirFullPath, filename + $" ({++i})" + extension);
+
+			return fullfilename;
+		}
+		private static string NEW_GetValidFilename_FileTemplate(string dirFullPath, string filename, string extension, string metadataSuffix)
+		{
+			var template = $"<title> [<id>]";
+
+			var fullfilename = Path.Combine(dirFullPath, template + FileUtility.GetStandardizedExtension(extension));
+
+			var fileTemplate = new FileTemplate(fullfilename) { IllegalCharacterReplacements = "_" };
+			fileTemplate.AddParameterReplacement("title", filename);
+			fileTemplate.AddParameterReplacement("id", metadataSuffix);
+			return fileTemplate.GetFilename();
+		}
+
+		[TestMethod]
+		public void equiv_GetMultipartFileName()
+		{
+			var expected = @"C:\foo\bar\my file - 002 - title.txt";
+			var f1 = OLD_GetMultipartFileName(@"C:\foo\bar\my file.txt", 2, 100, "title");
+			var f2 = NEW_GetMultipartFileName_FileTemplate(@"C:\foo\bar\my file.txt", 2, 100, "title");
+
+			f1.Should().Be(expected);
+			f1.Should().Be(f2);
+		}
+		private static string OLD_GetMultipartFileName(string originalPath, int partsPosition, int partsTotal, string suffix)
+		{
+			// 1-9     => 1-9
+			// 10-99   => 01-99
+			// 100-999 => 001-999
+			var chapterCountLeadingZeros = partsPosition.ToString().PadLeft(partsTotal.ToString().Length, '0');
+
+			string extension = Path.GetExtension(originalPath);
+
+			var filenameBase = $"{Path.GetFileNameWithoutExtension(originalPath)} - {chapterCountLeadingZeros}";
+			if (!string.IsNullOrWhiteSpace(suffix))
+				filenameBase += $" - {suffix}";
+
+			// Replace illegal path characters with spaces
+			var fileName = FileUtility.GetSafeFileName(filenameBase, " ");
+			var path = Path.Combine(Path.GetDirectoryName(originalPath), fileName + extension);
+			return path;
+		}
+		private static string NEW_GetMultipartFileName_FileTemplate(string originalPath, int partsPosition, int partsTotal, string suffix)
+		{
+			// 1-9     => 1-9
+			// 10-99   => 01-99
+			// 100-999 => 001-999
+			var chapterCountLeadingZeros = partsPosition.ToString().PadLeft(partsTotal.ToString().Length, '0');
+
+			var t = Path.ChangeExtension(originalPath, null) + " - <chapter> - <title>" + Path.GetExtension(originalPath);
+
+			var fileTemplate = new FileTemplate(t) { IllegalCharacterReplacements = " " };
+			fileTemplate.AddParameterReplacement("chapter", chapterCountLeadingZeros);
+			fileTemplate.AddParameterReplacement("title", suffix);
+
+			return fileTemplate.GetFilename();
+		}
+	}
+}