using System.Collections.Generic;

using Delta.Utilities;

using Delta.Utilities.Helpers;



namespace Delta.ContentSystem.Rendering

{

	/// <summary>

	/// Model data class, which combines a list of meshes and a list of mesh

	/// animations. Because models can have multiple meshes and animations they

	/// should be used for more complex 3d data. If you only need a static mesh

	/// just use the Mesh class, which is better optimized and can be used for

	/// level geometry with lots of extra optimizations and mesh merging than

	/// possibly than rendering everything as models.

	/// <para />

	/// Please note that Models just contain meshes and animations and have no

	/// data own their own (just meta data).

	/// </summary>

	public class ModelData : Content

	{

		#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 ModelData Get(string contentName)

		{

			return Get<ModelData>(contentName, ContentType.Model);

		}

		#endregion



		#region Meshes (Public)

		/// <summary>

		/// List of meshes to be used for this model. Often is just one mesh.

		/// Please note that we also will load and link up the animations inside

		/// of each mesh (see load method below), this way it is easier to manage.

		/// </summary>

		public List<MeshData> Meshes = new List<MeshData>();

		#endregion



		#region InitialScale (Public)

		/// <summary>

		/// Provides the initial scale value as provided by the content meta data.

		/// Usually 1.0f, which means rendering is done normally. If this value is

		/// different the content model will be scaled accordingly (should rarely

		/// be needed, scaling has obviously performance impacts, it is currently

		/// also ignored for most content types including meshes).

		/// </summary>

		public float InitialScale

		{

			get

			{

				return data.InitialScale;

			}

		}

		#endregion



		#region Constructors

		/// <summary>

		/// Create model data object with no data in it. Just add stuff to the

		/// Meshes and Animations fields.

		/// </summary>

		public ModelData()

			: base(EmptyName, ContentType.Model)

		{

		}



		/// <summary>

		/// Create mesh animation data by loading it from content, see Load below.

		/// Use the static Get method to call this.

		/// </summary>

		/// <param name="contentName">Name of the content.</param>

		protected ModelData(string contentName)

			: base(contentName, ContentType.Model)

		{

		}

		#endregion



		#region ToString (Public)

		/// <summary>

		/// To string, will display the model name with the meshes in it (plus

		/// optionally their animations if they have those).

		/// </summary>

		/// <returns>

		/// A <see cref="System.String"/> that represents this ModelData

		/// instance with the list of mesh names.

		/// </returns>

		public override string ToString()

		{

			return GetType().GetClassName() + " " + Name + ": " +

			       "Meshes=" + Meshes.Write();

		}

		#endregion



		#region Methods (Private)



		#region Load

		/// <summary>

		/// Native load method, will just load meshes and animations contained in

		/// this content type (models have no data on their own).

		/// </summary>

		/// <param name="alreadyLoadedNativeData">Ignored here, can't be cloned.

		/// </param>

		protected override void Load(Content alreadyLoadedNativeData)

		{

			// Initialize a new list for all the mesh children

			Meshes.Clear();

			// Note: Only direct mesh children nodes are allowed, nothing else!

			foreach (ContentMetaData childrenData in data.Children)

			{

				if (childrenData.Type != ContentType.Mesh)

				{

					Log.Warning("Invalid children node for " + this + " found, only " +

					            "mesh nodes are allowed: " + childrenData);

					// Skip this, maybe other data works

					continue;

				}

				// Note: We just add names, we don't want to load the images right away,

				// only when they need to be displayed they will be loaded (in the

				// Material class).

				Meshes.Add(MeshData.Get(childrenData.Name));

			}

			if (Meshes.Count == 0)

			{

				Log.Warning("No meshes found for " + this);

			}

		}

		#endregion



		#endregion

	}

}