using System;
using System.IO;
using System.Collections.Generic;

using Microsoft.Build.Framework;
using Microsoft.Build.Utilities;

using Xamarin.MacDev.Tasks;

namespace Xamarin.iOS.Tasks
{
	public abstract class GetDirectoriesTaskBase : Task
	{
		public string SessionId { get; set; }

		[Required]
		public string Path { get; set; }

		public string Pattern { get; set; }

		public string Option { get; set; }

		public string Exclude { get; set; }

		[Output]
		public ITaskItem[] Directories { get; set; }

		public override bool Execute ()
		{
			Log.LogTaskName ("GetDirectories");
			Log.LogTaskProperty ("Path", Path);
			Log.LogTaskProperty ("Pattern", Pattern);
			Log.LogTaskProperty ("Option", Option);
			Log.LogTaskProperty ("Exclude", Exclude);

			var path = Path.Replace ('\\', '/').TrimEnd ('/');
			var exclude = new HashSet<string> ();
			var items = new List<ITaskItem> ();
			IEnumerable<string> dirs;
			SearchOption option;

			if (!string.IsNullOrEmpty (Option)) {
				if (!Enum.TryParse (Option, out option)) {
					Log.LogError ("Unknown search option: {0}", Option);
					return false;
				}
			} else {
				option = SearchOption.TopDirectoryOnly;
			}

			if (!Directory.Exists (path)) {
				Directories = items.ToArray ();

				return !Log.HasLoggedErrors;
			}

			if (!string.IsNullOrEmpty (Pattern))
				dirs = Directory.EnumerateDirectories (path, Pattern, option);
			else
				dirs = Directory.EnumerateDirectories (path, "*.*", option);

			if (!string.IsNullOrEmpty (Exclude)) {
				foreach (var rpath in Exclude.Split (new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries)) {
					var full = System.IO.Path.Combine (path, rpath.Replace ('\\', '/'));
					exclude.Add (full);
				}
			}

			foreach (var dir in dirs) {
				if (!exclude.Contains (dir))
					items.Add (new TaskItem (dir));
			}

			Directories = items.ToArray ();

			return !Log.HasLoggedErrors;
		}
	}
}