Move source code into "Source" folder

Source/FileManager/FileNamingTemplate.cs

@@ -0,0 +1,64 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Dinah.Core;
+
+namespace FileManager
+{
+    /// <summary>Get valid filename. Advanced features incl. parameterized template</summary>
+    public class FileNamingTemplate
+    {
+        /// <summary>Proposed full file path. May contain optional html-styled template tags. Eg: &lt;name&gt;</summary>
+        public string Template { get; }
+
+        /// <param name="template">Proposed file name with optional html-styled template tags.</param>
+        public FileNamingTemplate(string template) => Template = ArgumentValidator.EnsureNotNullOrWhiteSpace(template, nameof(template));
+
+        /// <summary>Optional step 1: Replace html-styled template tags with parameters. Eg {"name", "Bill Gates"} => /&lt;name&gt;/ => /Bill Gates/</summary>
+        public Dictionary<string, object> ParameterReplacements { get; } = new Dictionary<string, object>();
+
+        /// <summary>Convenience method</summary>
+        public void AddParameterReplacement(string key, object value)
+            // using .Add() instead of "[key] = value" will make unintended overwriting throw exception
+            => ParameterReplacements.Add(key, value);
+
+        /// <summary>If set, truncate each parameter replacement to this many characters. Default 50</summary>
+        public int? ParameterMaxSize { get; set; } = 50;
+
+        /// <summary>Optional step 2: Replace all illegal characters with this. Default=<see cref="string.Empty"/></summary>
+        public string IllegalCharacterReplacements { get; set; }
+
+        /// <summary>Generate a valid path for this file or directory</summary>
+        public string GetFilePath(bool returnFirstExisting = false)
+        {
+            var filename = Template;
+
+            foreach (var r in ParameterReplacements)
+                filename = filename.Replace($"<{formatKey(r.Key)}>", formatValue(r.Value));
+
+            return FileUtility.GetValidFilename(filename, IllegalCharacterReplacements, returnFirstExisting);
+        }
+
+        private static string formatKey(string key)
+            => key
+            .Replace("<", "")
+            .Replace(">", "");
+
+        private string formatValue(object value)
+        {
+            if (value is null)
+                return "";
+
+            // Other illegal characters will be taken care of later. Must take care of slashes now so params can't introduce new folders.
+            // Esp important for file templates.
+            var val = value
+                .ToString()
+                .Replace($"{System.IO.Path.DirectorySeparatorChar}", IllegalCharacterReplacements)
+                .Replace($"{System.IO.Path.AltDirectorySeparatorChar}", IllegalCharacterReplacements);
+            return 
+                ParameterMaxSize.HasValue && ParameterMaxSize.Value > 0
+                ? val.Truncate(ParameterMaxSize.Value)
+                : val;
+        }
+    }
+}