using System;
using System.Threading.Tasks;
using Xamarin.Forms.CustomAttributes;
using Xamarin.Forms.Internals;

#if UITEST
using Xamarin.UITest;
using NUnit.Framework;
#endif

namespace Xamarin.Forms.Controls
{
	[Preserve (AllMembers = true)]
	[Issue (IssueTracker.Bugzilla, 36788, "Truncation Issues with Relative Layouts")]
	public class Bugzilla36788 : TestContentPage // or TestMasterDetailPage, etc ...
	{
		Label _resultLabel;
		Label _testLabel;
		View _container;

		protected override void Init ()
		{
			// Initialize ui here instead of ctor
			var stackLayout = new StackLayout {
				Spacing = 8
			};

			var longString = "Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated.";

			var contentView = new ContentView {
				Padding = 16,
				BackgroundColor = Color.Gray,
				Content = new Label {
					BackgroundColor = Color.Aqua,
					Text = longString,
					LineBreakMode = LineBreakMode.TailTruncation
				}
			};

			stackLayout.Children.Add (contentView);

			contentView = new ContentView {
				Padding = 16,
				BackgroundColor = Color.Gray,
				Content = new RelativeLayout {
					BackgroundColor = Color.Navy,
					Children = {
						{new Label {
							BackgroundColor = Color.Blue,
							Text = longString,
							LineBreakMode = LineBreakMode.TailTruncation
						}, Forms.Constraint.Constant (0)},
						{new Label {
							BackgroundColor = Color.Fuchsia,
							Text = longString,
							LineBreakMode = LineBreakMode.TailTruncation
						}, Forms.Constraint.Constant (0), Forms.Constraint.Constant (40)},
						{new Label {
							BackgroundColor = Color.Fuchsia,
							Text = longString,
							LineBreakMode = LineBreakMode.TailTruncation
						}, Forms.Constraint.Constant (10), Forms.Constraint.Constant (80)},
					}
				}
			};

			stackLayout.Children.Add (contentView);

			contentView = new ContentView {
				Padding = 16,
				BackgroundColor = Color.Gray,
				IsClippedToBounds = true,
				Content = _container = new RelativeLayout {
					IsClippedToBounds = true,
					BackgroundColor = Color.Navy,
					Children = {
						{_testLabel = new Label {
							BackgroundColor = Color.Blue,
							Text = longString,
							LineBreakMode = LineBreakMode.TailTruncation
						}, Forms.Constraint.Constant (0)},
						{new Label {
							BackgroundColor = Color.Fuchsia,
							Text = longString,
							LineBreakMode = LineBreakMode.TailTruncation
						}, Forms.Constraint.Constant (0), Forms.Constraint.Constant (40)},
						{new Label {
							BackgroundColor = Color.Fuchsia,
							Text = longString,
							LineBreakMode = LineBreakMode.TailTruncation
						}, Forms.Constraint.Constant (10), Forms.Constraint.Constant (80)},
					}
				}
			};

			stackLayout.Children.Add (contentView);

			_resultLabel = new Label ();
			stackLayout.Children.Add (_resultLabel);

			Content = stackLayout;
		}

		protected override async void OnAppearing ()
		{
			base.OnAppearing ();
			await Task.Delay (200);

			double fuzzFactor = 15; // labels sometimes overflow slightly, thanks hinting

			if (Math.Abs (_testLabel.Width - _container.Width) < fuzzFactor)
				_resultLabel.Text = "Passed";
		}

#if UITEST
		[Test]
		public void Bugzilla36788Test ()
		{
			RunningApp.WaitForElement (q => q.Marked ("Passed"));
		}
#endif
	}
}