using System;

using System.IO;

using Delta.Engine;

using Delta.Utilities;

using Delta.Utilities.Datatypes;

using Delta.Utilities.Helpers;



namespace Delta.ContentSystem.UserInterfaces

{

	/// <summary>

	/// The basic content class which is the base of all UI screen classes.

	/// Usually contains some screen global data, a link to the used UI Theme and

	/// a lot of controls in the form of BaseControlData.

	/// </summary>

	public abstract class BaseUIScreenData : Content, ISaveLoadBinary

	{

		#region Constants

		/// <summary>

		/// The newest version number of the screen data.

		/// </summary>

		private const int VersionNumber = 1;

		#endregion



		#region Get (Static)

		/// <summary>

		/// Get and load content based on the content name. This method makes sure

		/// we do not load the same content twice (the constructor is protected).

		/// </summary>

		/// <param name="contentName">Content name we want to load, this is

		/// passed onto the Content System, which will do the actual loading with

		/// help of the Load method in this class.</param>

		/// <returns>The loaded Content object, always unique for the same

		/// name, this helps comparing data.</returns>

		public static BaseUIScreenData Get(string contentName)

		{

			return Get<BaseUIScreenData>(contentName, ContentType.UIScreen);

		}

		#endregion



		#region DrawArea (Public)

		/// <summary>

		/// By default we render to Rectangle.One, which will be converted

		/// to Graphic.Instance.DrawArea, else use this size as a draw area!

		/// Note: Only used for UIScene.BackgroundDesign.Draw

		/// </summary>

		public Rectangle DrawArea

		{

			get

			{

				return (drawArea.HasValue)

				       	? drawArea.Value

				       	: ScreenSpace.DrawArea;

			} // get

			protected set

			{

				drawArea = (value != Rectangle.Zero)

				           	? drawArea = value

				           	: drawArea = null;

			} // set

		}

		#endregion



		#region Private



		#region drawArea (Private)

		/// <summary>

		/// Draw area

		/// </summary>

		private Rectangle? drawArea;

		#endregion



		#endregion



		#region Constructors

		/// <summary>

		/// Create scene content based on the content system. Loading happens in

		/// the Load method, all content is loaded right away.

		/// </summary>

		/// <param name="setContentName">Name of the scene name to load.</param>

		protected BaseUIScreenData(string setContentName)

			: base(setContentName, ContentType.UIScreen)

		{

		}

		#endregion



		#region ISaveLoadBinary Members

		/// <summary>

		/// Loads all data of the object again which were previously saved.

		/// </summary>

		/// <param name="dataReader">

		/// The container object which contains the data which were saved before.

		/// </param>

		public virtual void Load(BinaryReader dataReader)

		{

			int version = dataReader.ReadInt32();



			switch (version)

			{

					// Version 1

				case VersionNumber:

					DrawArea = new Rectangle(dataReader);

					break;



				default:

					Log.InvalidVersionWarning(GetType().Name, version, VersionNumber);

					return;

			} // switch

		}



		/// <summary>

		/// Saves all necessary data of the object into a binary stream.

		/// </summary>

		/// <param name="dataWriter">

		/// The container object which will store all the saved data.

		/// </param>

		public virtual void Save(BinaryWriter dataWriter)

		{

			dataWriter.Write(VersionNumber);



			// Determine if we have to save a custom screen area

			Rectangle areaToSave = (drawArea.HasValue)

			                       	? drawArea.Value

			                       	: Rectangle.Zero;

			areaToSave.Save(dataWriter);

		}

		#endregion



		#region Methods (Private)



		#region Load

		/// <summary>

		/// Native load method, will just load the data.

		/// </summary>

		/// <param name="alreadyLoadedNativeData">

		/// The first instance that has already loaded the required content data

		/// of this content class or just 'null' if there is none loaded yet (or

		/// anymore).

		/// </param>

		protected override void Load(Content alreadyLoadedNativeData)

		{

			try

			{

				// Note: Cloning is not needed for UI Screens (each is unique and we

				// don't share content or names, we can always load the same one again)

				if (String.IsNullOrEmpty(RelativeFilePath) == false)

				{

					// Load via the ISaveLoadBinary interface methods below.

					// Cloning should not really happen for screens anyway.

					FileHelper.Load(RelativeFilePath, this);

				}

			}

			catch (Exception ex)

			{

				Log.Warning("Failed to load mesh animation data from file '" +

				            RelativeFilePath + "': " + ex);

				FailedToLoad = true;

			}

		}

		#endregion



		#endregion

	}

}