PageTests.cs

using System;
using System.Collections.Generic;
using System.Linq;

using NUnit.Framework;
using Xamarin.Forms.Internals;

namespace Xamarin.Forms.Core.UnitTests
{
	[TestFixture]
	public class PageTests : BaseTestFixture
	{
		[TearDown]
		public override void TearDown()
		{
			base.TearDown ();
			MessagingCenter.ClearSubscribers();
		}

		[Test]
		public void TestConstructor ()
		{
			var child = new Label ();
			Page root = new ContentPage {Content = child};

			Assert.AreEqual (((IElementController)root).LogicalChildren.Count, 1);
			Assert.AreSame (((IElementController)root).LogicalChildren.First (), child);
		}

		[Test]
		public void TestChildFillBehavior ()
		{
			var child = new Label ();
			Page root = new ContentPage {Content = child};
			root.IsPlatformEnabled = child.IsPlatformEnabled = true;

			root.Layout (new Rectangle (0, 0, 200, 500));

			Assert.AreEqual (child.Width, 200);
			Assert.AreEqual (child.Height, 500);
		}

		[Test]
		public void TestSizedChildBehavior ()
		{
			var child = new Label {IsPlatformEnabled = true, WidthRequest = 100, HorizontalOptions = LayoutOptions.Center};
			var root = new ContentPage {IsPlatformEnabled = true, Content = child};
			
			root.Layout (new Rectangle (0, 0, 200, 500));

			Assert.AreEqual (50, child.X);
			Assert.AreEqual (100, child.Width);
			Assert.AreEqual (500, child.Height);

			child = new Label () {
				IsPlatformEnabled = true, 
				HeightRequest = 100, 
				VerticalOptions = LayoutOptions.Center
			};

			root = new ContentPage {
				IsPlatformEnabled = true, 
				Content = child
			};

			root.Layout (new Rectangle (0, 0, 200, 500));
			
			Assert.AreEqual (0, child.X);
			Assert.AreEqual (200, child.Y);
			Assert.AreEqual (200, child.Width);
			Assert.AreEqual (100, child.Height);

			child = new Label ();
			child.IsPlatformEnabled = true;
			child.HeightRequest = 100;
			
			root = new ContentPage {
				Content = child,
				IsPlatformEnabled = true
			};

			root.Layout (new Rectangle (0, 0, 200, 500));
			
			Assert.AreEqual (0, child.X);
			Assert.AreEqual (0, child.Y);
			Assert.AreEqual (200, child.Width);
			Assert.AreEqual (500, child.Height);
		}

		[Test]
		public void NativeSizedChildBehavior ()
		{
			var child = new Label {IsPlatformEnabled = true, HorizontalOptions = LayoutOptions.Center};
			var root = new ContentPage {IsPlatformEnabled = true, Content = child};
			
			root.Layout (new Rectangle (0, 0, 200, 500));

			Assert.AreEqual (50, child.X);
			Assert.AreEqual (100, child.Width);
			Assert.AreEqual (500, child.Height);

			child = new Label () {
				IsPlatformEnabled = true,
				VerticalOptions = LayoutOptions.Center
			};

			root = new ContentPage {
				IsPlatformEnabled = true, 
				Content = child
			};

			root.Layout (new Rectangle (0, 0, 200, 500));
			
			Assert.AreEqual (0, child.X);
			Assert.AreEqual (240, child.Y);
			Assert.AreEqual (200, child.Width);
			Assert.AreEqual (20, child.Height);
		}

		[Test]
		public void TestContentPageSetContent ()
		{
			View child;
			var page = new ContentPage {Content = child = new View ()};

			Assert.AreEqual (child, page.Content);

			bool fired = false;
			page.PropertyChanged += (sender, args) => {
				if (args.PropertyName == "Content")
					fired = true;
			};

			page.Content = child;
			Assert.False (fired);

			page.Content = new View ();
			Assert.True (fired);

			page.Content = null;
			Assert.Null (page.Content);
		}

		[Test]
		public void TestLayoutChildrenFill ()
		{
			View child;
			var page = new ContentPage {
				Content = child = new View {
					WidthRequest = 100,
					HeightRequest = 200,
					IsPlatformEnabled = true
				},
				IsPlatformEnabled = true,
			};

			page.Layout (new Rectangle (0, 0, 800, 800));

			Assert.AreEqual (new Rectangle (0, 0, 800, 800), child.Bounds);

			page.Layout (new Rectangle (0, 0, 50, 50));

			Assert.AreEqual (new Rectangle (0, 0, 50, 50), child.Bounds);
		}

		[Test]
		public void TestLayoutChildrenStart ()
		{
			View child;
			var page = new ContentPage {
				Content = child = new View {
					WidthRequest = 100,
					HeightRequest = 200,
					HorizontalOptions = LayoutOptions.Start,
					VerticalOptions = LayoutOptions.Start,
					IsPlatformEnabled = true
				},
				IsPlatformEnabled = true,
			};

			page.Layout (new Rectangle (0, 0, 800, 800));

			Assert.AreEqual (new Rectangle (0, 0, 100, 200), child.Bounds);

			page.Layout (new Rectangle (0, 0, 50, 50));

			Assert.AreEqual (new Rectangle (0, 0, 50, 50), child.Bounds);
		}

		[Test]
		public void TestLayoutChildrenEnd ()
		{
			View child;
			var page = new ContentPage {
				Content = child = new View {
					WidthRequest = 100,
					HeightRequest = 200,
					HorizontalOptions = LayoutOptions.End,
					VerticalOptions = LayoutOptions.End,
					IsPlatformEnabled = true
				},
				IsPlatformEnabled = true,
			};

			page.Layout (new Rectangle (0, 0, 800, 800));

			Assert.AreEqual (new Rectangle (700, 600, 100, 200), child.Bounds);

			page.Layout (new Rectangle (0, 0, 50, 50));

			Assert.AreEqual (new Rectangle (0, 0, 50, 50), child.Bounds);
		}

		[Test]
		public void TestLayoutChildrenCenter ()
		{
			View child;
			var page = new ContentPage {
				Content = child = new View {
					WidthRequest = 100,
					HeightRequest = 200,
					HorizontalOptions = LayoutOptions.Center,
					VerticalOptions = LayoutOptions.Center,
					IsPlatformEnabled = true
				},
				IsPlatformEnabled = true,
			};

			page.Layout (new Rectangle (0, 0, 800, 800));

			Assert.AreEqual (new Rectangle (350, 300, 100, 200), child.Bounds);

			page.Layout (new Rectangle (0, 0, 50, 50));

			Assert.AreEqual (new Rectangle (0, 0, 50, 50), child.Bounds);
		}

		[Test]
		public void TestLayoutWithContainerArea ()
		{
			View child;
			var page = new ContentPage {
				Content = child = new View {
					WidthRequest = 100,
					HeightRequest = 200,
					IsPlatformEnabled = true
				},
				IsPlatformEnabled = true,
			};

			page.Layout (new Rectangle (0, 0, 800, 800));

			Assert.AreEqual (new Rectangle (0, 0, 800, 800), child.Bounds);
			((IPageController)page).ContainerArea = new Rectangle (10, 10, 30, 30);

			Assert.AreEqual (new Rectangle (10, 10, 30, 30), child.Bounds);

			page.Layout (new Rectangle (0, 0, 50, 50));

			Assert.AreEqual (new Rectangle (10, 10, 30, 30), child.Bounds);
		}

		[Test]
		public void TestThrowOnInvalidAlignment ()
		{
			bool thrown = false;

			try {
				new ContentPage {
					Content = new View {
						WidthRequest = 100,
						HeightRequest = 200,
						HorizontalOptions = new LayoutOptions((LayoutAlignment) int.MaxValue, false),
						VerticalOptions = LayoutOptions.Center,
						IsPlatformEnabled = true
					},
					IsPlatformEnabled = true,
				};
			} catch (ArgumentOutOfRangeException) {
				thrown = true;
			}

			Assert.True (thrown);
		}

		[Test]
		public void BusyNotSentWhenNotVisible ()
		{
			var sent = false;
			MessagingCenter.Subscribe<Page, bool> (this, Page.BusySetSignalName, (p, b) => sent = true);

			new ContentPage { IsBusy = true };

			Assert.That (sent, Is.False, "Busy message sent while not visible");
		}

		[Test]
		public void BusySentWhenBusyPageAppears()
		{
			var sent = false;
			MessagingCenter.Subscribe<Page, bool> (this, Page.BusySetSignalName, (p, b) => {
				Assert.That (b, Is.True);
				sent = true;
			});

			var page = new ContentPage { IsBusy = true, IsPlatformEnabled = true };

			Assert.That (sent, Is.False, "Busy message sent while not visible");

			((IPageController)page).SendAppearing();

			Assert.That (sent, Is.True, "Busy message not sent when visible");
		}

		[Test]
		public void BusySentWhenBusyPageDisappears()
		{
			var page = new ContentPage { IsBusy = true };
			((IPageController)page).SendAppearing();

			var sent = false;
			MessagingCenter.Subscribe<Page, bool> (this, Page.BusySetSignalName, (p, b) => {
				Assert.That (b, Is.False);
				sent = true;
			});

			((IPageController)page).SendDisappearing();

			Assert.That (sent, Is.True, "Busy message not sent when visible");
		}

		[Test]
		public void BusySentWhenVisiblePageSetToBusy()
		{
			var sent = false;
			MessagingCenter.Subscribe<Page, bool> (this, Page.BusySetSignalName, (p, b) => sent = true);

			var page = new ContentPage();
			((IPageController)page).SendAppearing();

			Assert.That (sent, Is.False, "Busy message sent appearing while not busy");

			page.IsBusy = true;

			Assert.That (sent, Is.True, "Busy message not sent when visible");
		}

		[Test]
		public void DisplayAlert ()
		{
			var page = new ContentPage() { IsPlatformEnabled = true };

			AlertArguments args = null;
			MessagingCenter.Subscribe (this, Page.AlertSignalName, (Page sender, AlertArguments e) => args = e);

			var task = page.DisplayAlert ("Title", "Message", "Accept", "Cancel");

			Assert.AreEqual ("Title", args.Title);
			Assert.AreEqual ("Message", args.Message);
			Assert.AreEqual ("Accept", args.Accept);
			Assert.AreEqual ("Cancel", args.Cancel);

			bool completed = false;
			var continueTask = task.ContinueWith (t => completed = true);

			args.SetResult (true);
			continueTask.Wait ();
			Assert.True (completed);
		}

		[Test]
		public void DisplayActionSheet ()
		{
			var page = new ContentPage() { IsPlatformEnabled = true };

			ActionSheetArguments args = null;
			MessagingCenter.Subscribe (this, Page.ActionSheetSignalName, (Page sender, ActionSheetArguments e) => args = e);

			var task = page.DisplayActionSheet ("Title", "Cancel", "Destruction", "Other 1", "Other 2");

			Assert.AreEqual ("Title", args.Title);
			Assert.AreEqual ("Destruction", args.Destruction);
			Assert.AreEqual ("Cancel", args.Cancel);
			Assert.AreEqual ("Other 1", args.Buttons.First());
			Assert.AreEqual ("Other 2", args.Buttons.Skip (1).First());

			bool completed = false;
			var continueTask = task.ContinueWith (t => completed = true);

			args.SetResult ("Cancel");
			continueTask.Wait ();
			Assert.True (completed);
		}

		class PageTestApp : Application { }

		[Test]
		public void SendApplicationPageAppearing()
		{
			var app = new PageTestApp();
			var page = new ContentPage();

			Page actual = null;
			app.MainPage = page;
			app.PageAppearing += (sender, args) => actual = args;

			((IPageController)page).SendAppearing();

			Assert.AreSame(page, actual);
		}

		[Test]
		public void SendApplicationPageDisappearing()
		{
			var app = new PageTestApp();
			var page = new ContentPage();

			Page actual = null;
			app.MainPage = page;
			app.PageDisappearing += (sender, args) => actual = args;

			((IPageController)page).SendAppearing();
			((IPageController)page).SendDisappearing();

			Assert.AreSame(page, actual);
		}

		[Test]
		public void SendAppearing ()
		{
			var page = new ContentPage ();

			bool sent = false;
			page.Appearing += (sender, args) => sent = true;

			((IPageController)page).SendAppearing ();

			Assert.True (sent);
		}

		[Test]
		public void SendDisappearing ()
		{
			var page = new ContentPage ();

			((IPageController)page).SendAppearing ();

			bool sent = false;
			page.Disappearing += (sender, args) => sent = true;

			((IPageController)page).SendDisappearing ();

			Assert.True (sent);
		}

		[Test]
		public void SendAppearingDoesntGetCalledMultipleTimes ()
		{
			var page = new ContentPage ();

			int countAppearing = 0;
			page.Appearing += (sender, args) => countAppearing++;

			((IPageController)page).SendAppearing ();
			((IPageController)page).SendAppearing ();

			Assert.That (countAppearing, Is.EqualTo(1));
		}

		[Test]
		public void IsVisibleWorks ()
		{
			var page = new ContentPage ();
			page.IsVisible = false;
			Assert.False (page.IsVisible);
		}

		[Test]
		public void SendAppearingToChildrenAfter ()
		{
			var page = new ContentPage ();

			var navPage = new NavigationPage (page);

			bool sentNav = false;
			bool sent = false;
			page.Appearing += (sender, args) => {
				if (sentNav)
					sent = true;
			};
			navPage.Appearing += (sender, e) => sentNav = true;

			((IPageController)navPage).SendAppearing ();

			Assert.True (sentNav);
			Assert.True (sent);

		}

		[Test]
		public void SendDisappearingToChildrenPageFirst ()
		{
			var page = new ContentPage ();

			var navPage = new NavigationPage (page);
			((IPageController)navPage).SendAppearing ();

			bool sentNav = false;
			bool sent = false;
			page.Disappearing += (sender, args) => {
				sent = true;
			};
			navPage.Disappearing += (sender, e) => {
				if (sent)
					sentNav = true;
			};
			((IPageController)navPage).SendDisappearing ();

			Assert.True (sentNav);
			Assert.True (sent);
		}
	}
}