Update generation and error handling

src/OpenApi.Client.Cli/Commands/GenerateCommand.cs

@@ -3,8 +3,10 @@
 // Copyright (C) Leszek Pomianowski and OpenAPI Client Contributors.
 // All Rights Reserved.
 
-using System.Text.RegularExpressions;
+using Microsoft.CodeAnalysis;
 using OpenApi.Client.Cli.Settings;
+using OpenApi.Client.SourceGenerators.Contracts;
+using OpenApi.Client.SourceGenerators.Genertion;
 using OpenApi.Client.SourceGenerators.Schema;
 using OpenApi.Client.SourceGenerators.Serialization;
 
@@ -22,17 +24,73 @@ public sealed class GenerateCommand : AsyncCommand<GenerateCommandSettings>
 {
     private static readonly Regex PathNormalizer = new(@"(\\\\|//)", RegexOptions.Compiled);
 
+    private static readonly Regex NamespaceValidator =
+        new(@"^[_a-zA-Z][_a-zA-Z0-9]*(\.[_a-zA-Z][_a-zA-Z0-9]*)*$", RegexOptions.Compiled);
+
+    private static readonly Regex ClassNameValidator =
+        new(@"^[_a-zA-Z][_a-zA-Z0-9]*$", RegexOptions.Compiled);
+
     /// <inheritdoc />
     public override async Task<int> ExecuteAsync(
         CommandContext context,
         GenerateCommandSettings settings
     )
     {
+        using CancellationTokenSource cancellationTokenSource = new();
         string contents = await File.ReadAllTextAsync(settings.File);
 
         SerializationResult<IApiDocument>? serializationResult =
             new OpenApiSerializer().Deserialize(settings.File, contents);
 
+        if (serializationResult.HasErrors)
+        {
+            foreach (
+                SerializationResultError serializationResultError in serializationResult.Errors
+            )
+            {
+                AnsiConsole.MarkupLine($"[red]Error: {serializationResultError.Message}[/]");
+            }
+
+            return -1;
+        }
+
+        if (serializationResult.Result is null)
+        {
+            AnsiConsole.MarkupLine($"[red]Error: Serialized JSON returned empty API.[/]");
+
+            return -2;
+        }
+
+        string? generatedSource = null;
+
+        OpenApiContract contract = OpenApiContractParser.Parse(
+            settings.Namespace,
+            settings.ClassName,
+            Accessibility.Public,
+            serializationResult.Result
+        );
+
+        ClientGenerator generator = new(contract);
+        GenerationResult<string> generatorResult = generator.Generate();
+
+        if (generatorResult.HasErrors)
+        {
+            foreach (GenerationResultError generatorResultError in generatorResult.Errors)
+            {
+                AnsiConsole.MarkupLine($"[red]Error: {generatorResultError.Message}[/]");
+            }
+
+            return -1;
+        }
+
+        generatedSource = generatorResult.Result;
+
+        await File.WriteAllTextAsync(
+            settings.Output,
+            generatedSource,
+            cancellationTokenSource.Token
+        );
+
         return 0;
     }
 
@@ -42,6 +100,29 @@ public override ValidationResult Validate(
         GenerateCommandSettings settings
     )
     {
+        if (string.IsNullOrEmpty(settings.ClassName))
+        {
+            settings.ClassName = Path.GetFileNameWithoutExtension(settings.Output);
+        }
+
+        settings.ClassName = settings.ClassName.Trim();
+
+        if (!ClassNameValidator.IsMatch(settings.ClassName))
+        {
+            return ValidationResult.Error(
+                $"The name '{settings.ClassName}' is not valid C# type name."
+            );
+        }
+
+        settings.Namespace = settings.Namespace.Trim();
+
+        if (!NamespaceValidator.IsMatch(settings.Namespace))
+        {
+            return ValidationResult.Error(
+                $"The namespace '{settings.Namespace}' is not valid C# namespace."
+            );
+        }
+
         settings.File = PathNormalizer.Replace(settings.File, "/");
         settings.File = settings.File.Replace("\\", "/");
 
@@ -50,6 +131,9 @@ GenerateCommandSettings settings
             return ValidationResult.Error($"The file '{settings.File}' does not exist.");
         }
 
+        settings.Output = PathNormalizer.Replace(settings.Output, "/");
+        settings.Output = settings.Output.Replace("\\", "/");
+
         return ValidationResult.Success();
     }
 }

src/OpenApi.Client.Cli/Settings/GenerateCommandSettings.cs

@@ -31,6 +31,20 @@ public sealed class GenerateCommandSettings : CommandSettings
     [Description("The output directory.")]
     public string Output { get; set; } = "./";
 
+    /// <summary>
+    /// Gets or sets the name of the generated class.
+    /// </summary>
+    [CommandOption("-c|--classname <NAMESPACE>")]
+    [Description("The name of the generated class..")]
+    public string ClassName { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the namespace for the generated class.
+    /// </summary>
+    [CommandOption("-n|--namespace <NAMESPACE>")]
+    [Description("The namespace in which the class is to be placed.")]
+    public string Namespace { get; set; } = "OpenApi";
+
     /// <summary>
     /// Gets or sets the JSON serializer to use. If not provided, System.Text.Json is used.
     /// </summary>