winure/qdls/Program.cs

using System.IO;

using Qdls;

//	collect args; no args becomes working directory
string[] arguments;
if(args.Length == 0)
	arguments = ["."];
else
	arguments = args;

//	flags
bool showHidden = true;

//	run on targets
foreach(var arg in arguments) {
	//	don't try to list nonexistent entries or files
	if(!Path.Exists(arg))
		Console.WriteLine($"'{arg}: does not exist");
	if(File.Exists(arg))
		Console.WriteLine($"'{arg}: is file");

	//	fetch children
	var children = Directory.GetFileSystemEntries(arg);

	//	state vars
	var buffer = "";
	var longest = children.OrderByDescending(s => Path.GetFileName(s).Length).First().Length;
	var columns = Console.WindowWidth / (longest + 2);
	var multiline = columns < args.Length;
	var position = -1;

	//	print names if more than one target
	if(args.Length > 1)
		Console.WriteLine($"{arg}:");
	//	iterate over children; build buffer and output when full
	foreach(var child in children) {
		var name = Path.GetFileName(child);

		//	skip or format hidden files
		if(Util.IsHidden(child))
			if(showHidden)
				buffer += Format.Hidden;
			else
				continue;

		//	format directories
		if(Directory.Exists(child))
			buffer += Format.Directory;

		//	if we pass max width, write buffer and clear
		if( multiline && (++position > columns) ) {
			position = -1;
			Console.WriteLine(buffer);
			buffer = "";
		}
		if(multiline)
			buffer += $"{name}{Format.Reset}".PadRight(longest) + "  ";
		else
			buffer += $"{name}{Format.Reset}  ";

	}

	//	print last line
	Console.WriteLine(buffer);
}