process/src/process.dummy.app/_commands/EchoCommand.cs

// Copyright (c) The Geekeey Authors
// SPDX-License-Identifier: EUPL-1.2

using System.CommandLine;

internal sealed class EchoCommand : Command
{
	private static readonly Option<OutputTarget> Target = new("--target") { DefaultValueFactory = _ => OutputTarget.StdOut };
	private static readonly Option<string> Separator = new("--separator") { DefaultValueFactory = _ => " " };
	private static readonly Argument<string[]> Items = new("line") { Arity = ArgumentArity.ZeroOrMore, DefaultValueFactory = _ => [] };

	public EchoCommand() : base("echo")
	{
		Add(Target);
		Add(Separator);
		Add(Items);
		SetAction(ExecuteAsync);
	}

	public async Task<int> ExecuteAsync(ParseResult result, CancellationToken cancellationToken)
	{
		using var output = Output.Connect();

		foreach (var writer in output.GetWriters(result.GetValue(Target)))
		{
			await writer.WriteLineAsync(string.Join(result.GetRequiredValue(Separator), result.GetRequiredValue(Items)));
		}

		return 0;
	}
}