using System;
using System.Reflection;
using Tizen.Applications;
using ElmSharp;

namespace Xamarin.Forms.Platform.Tizen
{
	public static class Forms
	{
		class TizenDeviceInfo : DeviceInfo
		{
			readonly Size pixelScreenSize;

			readonly Size scaledScreenSize;

			readonly double scalingFactor;

			public override Size PixelScreenSize
			{
				get
				{
					return this.pixelScreenSize;
				}
			}

			public override Size ScaledScreenSize
			{
				get
				{
					return this.scaledScreenSize;
				}
			}

			public override double ScalingFactor
			{
				get
				{
					return this.scalingFactor;
				}
			}

			public TizenDeviceInfo(FormsApplication formsApplication)
			{
				// TODO: obtain screen data from device
				pixelScreenSize = new Size();
				scaledScreenSize = new Size();
				scalingFactor = 0.0;
			}
		}

		public static event EventHandler<ViewInitializedEventArgs> ViewInitialized;

		public static FormsApplication Context
		{
			get;
			internal set;
		}

		public static bool IsInitialized
		{
			get;
			private set;
		}

		internal static TizenTitleBarVisibility TitleBarVisibility
		{
			get;
			private set;
		}

		internal static void SendViewInitialized(this VisualElement self, EvasObject nativeView)
		{
			EventHandler<ViewInitializedEventArgs> viewInitialized = Forms.ViewInitialized;
			if (viewInitialized != null)
			{
				viewInitialized.Invoke(self, new ViewInitializedEventArgs
				{
					View = self,
					NativeView = nativeView
				});
			}
		}

		public static void SetTitleBarVisibility(TizenTitleBarVisibility visibility)
		{
			TitleBarVisibility = visibility;
		}

		public static void Init(FormsApplication application)
		{
			SetupInit(application);
		}

		static void SetupInit(FormsApplication application)
		{
			Color.Accent = GetAccentColor();

			Context = application;

			if (!IsInitialized)
			{
				Xamarin.Forms.Log.Listeners.Add(new XamarinLogListener());
				if (System.Threading.SynchronizationContext.Current == null)
				{
					TizenSynchronizationContext.Initialize();
				}
				Elementary.Initialize();
				Elementary.ThemeOverlay();
			}

			//TO-DO: Need to change to Tizen.
			Device.OS = TargetPlatform.Other;

#if !NET45
			// In .NETCore, AppDomain feature is not supported.
			// The list of assemblies returned by AppDomain.GetAssemblies() method should be registered manually.
			// The assembly of the executing application and referenced assemblies of it are added into the list here.
			Assembly asm = application.GetType().GetTypeInfo().Assembly;
			TizenPlatformServices.AppDomain.CurrentDomain.RegisterAssembly(asm);
			foreach (var refName in asm.GetReferencedAssemblies())
			{
				if (!refName.Name.StartsWith("System.") && !refName.Name.StartsWith("Microsoft."))
				{
					try
					{
						Assembly refAsm = Assembly.Load(refName);
						TizenPlatformServices.AppDomain.CurrentDomain.RegisterAssembly(refAsm);
					}
					catch
					{
						Log.Warn("Reference Assembly can not be loaded. {0}", refName.FullName);
					}
				}
			}
#endif

			Device.PlatformServices = new TizenPlatformServices(); ;
			if (Device.info != null)
			{
				((TizenDeviceInfo)Device.info).Dispose();
				Device.info = null;
			}

			Device.Info = new Forms.TizenDeviceInfo(application);

			if (!Forms.IsInitialized)
			{
				Registrar.RegisterAll(new Type[]
				{
					typeof(ExportRendererAttribute),
					typeof(ExportImageSourceHandlerAttribute),
					typeof(ExportCellAttribute),
				});
			}

			// FIXME: We should consider TV and Common (Desktop) profiles also.
			Device.Idiom = TargetIdiom.Phone;

			IsInitialized = true;
		}

		static Color GetAccentColor()
		{
			// On Windows Phone, this is the complementary color chosen by the user.
			// Good Windows Phone applications use this as part of their styling to provide a native look and feel.
			// On iOS and Android this instance is set to a contrasting color that is visible on the default
			// background but is not the same as the default text color.

			// TODO: implement me
			return Color.Black;
		}
	}
}