Added command line help to the lookup tool

src/MusicCatalogue.Entities/CommandLine/CommandLineOptionType.cs

@@ -3,6 +3,7 @@
     public enum CommandLineOptionType
     {
         Unknown,
+        Help,
         Lookup,
         Import,
         Export,

src/MusicCatalogue.Entities/Interfaces/ICommandLineParser.cs

@@ -0,0 +1,13 @@
+using MusicCatalogue.Entities.CommandLine;
+
+namespace MusicCatalogue.Entities.Interfaces
+{
+    public interface ICommandLineParser
+    {
+        void Add(CommandLineOptionType optionType, bool isOperation, string name, string shortName, string description, int minimumNumberOfValues, int maximumNumberOfValues);
+        List<string>? GetValues(CommandLineOptionType optionType);
+        bool IsPresent(CommandLineOptionType optionType);
+        void Help();
+        void Parse(IEnumerable<string> args);
+    }
+}

src/MusicCatalogue.Entities/Interfaces/IHelpGenerator.cs

@@ -0,0 +1,9 @@
+using MusicCatalogue.Entities.CommandLine;
+
+namespace MusicCatalogue.Entities.Interfaces
+{
+    public interface IHelpGenerator
+    {
+        void Generate(IEnumerable<CommandLineOption> options);
+    }
+}

src/MusicCatalogue.Logic/CommandLine/CommandLineParser.cs

@@ -1,12 +1,19 @@
 using MusicCatalogue.Entities.CommandLine;
 using MusicCatalogue.Entities.Exceptions;
+using MusicCatalogue.Entities.Interfaces;
 
 namespace MusicCatalogue.Logic.CommandLine
 {
-    public class CommandLineParser
+    public class CommandLineParser : ICommandLineParser
     {
         private readonly List<CommandLineOption> _options = new List<CommandLineOption>();
         private readonly Dictionary<CommandLineOptionType, CommandLineOptionValue> _values = new Dictionary<CommandLineOptionType, CommandLineOptionValue>();
+        private readonly IHelpGenerator? _helpGenerator = null;
+
+        public CommandLineParser() { }
+
+        public CommandLineParser(IHelpGenerator generator)
+            => _helpGenerator = generator;
 
         /// <summary>
         /// Add an option to the available command line options
@@ -70,6 +77,14 @@ public void Parse(IEnumerable<string> args)
             CheckForSingleOperation();
         }
 
+        /// <summary>
+        /// Return true if a command line option has been specified
+        /// </summary>
+        /// <param name="optionType"></param>
+        /// <returns></returns>
+        public bool IsPresent(CommandLineOptionType optionType)
+            => _values.ContainsKey(optionType);
+
         /// <summary>
         /// Return the valus for the specified option type
         /// </summary>
@@ -79,14 +94,20 @@ public void Parse(IEnumerable<string> args)
         {
             List<string>? values = null;
 
-            if (_values.ContainsKey(optionType))
+            if (IsPresent(optionType))
             {
                 values = _values[optionType].Values;
             }
 
             return values;
         }
 
+        /// <summary>
+        /// Generate help
+        /// </summary>
+        public void Help()
+            => _helpGenerator?.Generate(_options);
+
         /// <summary>
         /// Check that each supplied option has sufficient values with it
         /// </summary>

src/MusicCatalogue.LookupTool/Logic/HelpTabulator.cs

@@ -0,0 +1,43 @@
+using MusicCatalogue.Entities.CommandLine;
+using MusicCatalogue.Entities.Interfaces;
+using Spectre.Console;
+
+namespace MusicCatalogue.LookupTool.Logic
+{
+
+    public class HelpTabulator : IHelpGenerator
+    {
+        /// <summary>
+        /// Tabulate a collection of available command line options
+        /// </summary>
+        /// <param name="options"></param>
+        public void Generate(IEnumerable<CommandLineOption> options)
+        {
+            var table = new Table();
+
+            table.AddColumn("Option");
+            table.AddColumn("Short Form");
+            table.AddColumn("Min Values");
+            table.AddColumn("Max Values");
+            table.AddColumn("Description");
+
+            foreach (var option in options)
+            {
+                var rowData = new string[] {
+                    GetCellData(option.Name),
+                    GetCellData(option.ShortName),
+                    GetCellData(option.MinimumNumberOfValues.ToString()),
+                    GetCellData(option.MaximumNumberOfValues.ToString()),
+                    GetCellData(option.Description)
+                };
+
+                table.AddRow(rowData);
+            }
+
+            AnsiConsole.Write(table);
+        }
+
+        private string GetCellData(string value)
+            => $"[white]{value}[/]";
+    }
+}

src/MusicCatalogue.LookupTool/MusicCatalogue.LookupTool.csproj

@@ -3,9 +3,9 @@
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <TargetFramework>net8.0</TargetFramework>
-    <ReleaseVersion>1.24.0.0</ReleaseVersion>
-    <FileVersion>1.24.0.0</FileVersion>
-    <ProductVersion>1.24.0</ProductVersion>
+    <ReleaseVersion>1.25.0.0</ReleaseVersion>
+    <FileVersion>1.25.0.0</FileVersion>
+    <ProductVersion>1.25.0</ProductVersion>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <IsPackable>false</IsPackable>
@@ -26,6 +26,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
+    <PackageReference Include="Spectre.Console" Version="0.49.1" />
   </ItemGroup>
 
   <ItemGroup>

src/MusicCatalogue.LookupTool/Program.cs

@@ -13,7 +13,7 @@
 using System.Diagnostics;
 using System.Reflection;
 
-namespace MusicCatalogue.LookupPoC
+namespace MusicCatalogue.LookupTool
 {
     public static class Program
     {
@@ -24,60 +24,70 @@ public static class Program
         /// <returns></returns>
         public static async Task Main(string[] args)
         {
-            // Read the application settings
-            MusicApplicationSettings? settings = new MusicCatalogueConfigReader().Read("appsettings.json");
-
-            // Configure the log file
-            FileLogger logger = new FileLogger();
-            logger.Initialise(settings!.LogFile, settings.MinimumLogLevel);
-
-            // Get the version number and application title
-            Assembly assembly = Assembly.GetExecutingAssembly();
-            FileVersionInfo info = FileVersionInfo.GetVersionInfo(assembly.Location);
-            var title = $"Music Catalogue Lookup Tool v{info.FileVersion}";
-
-            // Log the startup messages
-            Console.WriteLine($"{title}\n");
-            logger.LogMessage(Severity.Info, new string('=', 80));
-            logger.LogMessage(Severity.Info, title);
 
             try
             {
                 // Parse the command line
-                CommandLineParser parser = new();
+                CommandLineParser parser = new(new HelpTabulator());
+                parser.Add(CommandLineOptionType.Help, true, "--help", "-h", "Show command line help", 0, 0);
                 parser.Add(CommandLineOptionType.Lookup, true, "--lookup", "-l", "Lookup an album and display its details", 3, 3);
                 parser.Add(CommandLineOptionType.Import, true, "--import", "-i", "Import data from a CSV format file", 1, 1);
                 parser.Add(CommandLineOptionType.Export, true, "--export", "-e", "Export the collection or equipment register to a CSV file or Excel Workbook", 2, 2);
                 parser.Parse(args);
 
-                // Configure the business logic factory
-                var context = new MusicCatalogueDbContextFactory().CreateDbContext(Array.Empty<string>());
-                var factory = new MusicCatalogueFactory(context);
-
-                // If this is a lookup, look up the album details
-                var values = parser.GetValues(CommandLineOptionType.Lookup);
-                if (values != null)
+                // If help's been requested, show help and exit
+                if (parser.IsPresent(CommandLineOptionType.Help))
                 {
-                    // Determine the target for new albums (catalogue or wish list) and lookup the album
-                    var targetType = (TargetType)Enum.Parse(typeof(TargetType), values[2]);
-                    var storeInWishList = targetType == TargetType.wishlist;
-                    await new AlbumLookup(logger, factory, settings!).LookupAlbum(values[0], values[1], storeInWishList);
+                    parser.Help();
                 }
-
-                // If this is an import, import data from the specified CSV file
-                values = parser.GetValues(CommandLineOptionType.Import);
-                if (values != null)
+                else
                 {
-                    new DataImport(logger, factory).Import(values[0]);
-                }
+                    // Read the application settings
+                    MusicApplicationSettings? settings = new MusicCatalogueConfigReader().Read("appsettings.json");
 
-                // If this is an export, export the collection to the specified file
-                values = parser.GetValues(CommandLineOptionType.Export);
-                if (values != null)
-                {
-                    var exportType = (ExportType)Enum.Parse(typeof(ExportType), values[0]);
-                    IDataExporter exporter = exportType == ExportType.music ? new CatalogueExporter(logger, factory) : new EquipmentExporter(logger, factory);
-                    exporter.Export(values[1]);
+                    // Configure the log file
+                    FileLogger logger = new FileLogger();
+                    logger.Initialise(settings!.LogFile, settings.MinimumLogLevel);
+
+                    // Get the version number and application title
+                    Assembly assembly = Assembly.GetExecutingAssembly();
+                    FileVersionInfo info = FileVersionInfo.GetVersionInfo(assembly.Location);
+                    var title = $"Music Catalogue Lookup Tool v{info.FileVersion}";
+
+                    // Log the startup messages
+                    Console.WriteLine($"{title}\n");
+                    logger.LogMessage(Severity.Info, new string('=', 80));
+                    logger.LogMessage(Severity.Info, title);
+
+                    // Configure the business logic factory
+                    var context = new MusicCatalogueDbContextFactory().CreateDbContext(Array.Empty<string>());
+                    var factory = new MusicCatalogueFactory(context);
+
+                    // If this is a lookup, look up the album details
+                    var values = parser.GetValues(CommandLineOptionType.Lookup);
+                    if (values != null)
+                    {
+                        // Determine the target for new albums (catalogue or wish list) and lookup the album
+                        var targetType = (TargetType)Enum.Parse(typeof(TargetType), values[2]);
+                        var storeInWishList = targetType == TargetType.wishlist;
+                        await new AlbumLookup(logger, factory, settings!).LookupAlbum(values[0], values[1], storeInWishList);
+                    }
+
+                    // If this is an import, import data from the specified CSV file
+                    values = parser.GetValues(CommandLineOptionType.Import);
+                    if (values != null)
+                    {
+                        new DataImport(logger, factory).Import(values[0]);
+                    }
+
+                    // If this is an export, export the collection to the specified file
+                    values = parser.GetValues(CommandLineOptionType.Export);
+                    if (values != null)
+                    {
+                        var exportType = (ExportType)Enum.Parse(typeof(ExportType), values[0]);
+                        IDataExporter exporter = exportType == ExportType.music ? new CatalogueExporter(logger, factory) : new EquipmentExporter(logger, factory);
+                        exporter.Export(values[1]);
+                    }
                 }
             }
             catch (Exception ex)