using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Aiwaz.Contracts;
using Aiwaz.Core;
using Aiwaz.Resources.Attributes;
using System.Collections.ObjectModel;

namespace Aiwaz.Resources
{
    [CreationParameters("Create an empty RenderTarget texture")]
    public class RenderTargetTextureParams : ICreationParams
    {
        public int width;
        public int height;
        public SlimDX.DXGI.Format format;
        public int multiSampleCount;
        public int multiSampleQuality;

        public RenderTargetTextureParams()
        {
            width = 512;
            height = 512;
            format = SlimDX.DXGI.Format.Unknown;
            multiSampleCount = 0;
            multiSampleQuality = 0;
        }
    }

    [AiwazResource("RenderTarget texture", "An output target for render operations which could be used as texture input.")]
    public class RenderTargetTexture : RenderTarget
    {
        public RenderTargetTexture(RenderTargetTextureParams parameters)
            : base()
        {
            creationParams = parameters;
            Console.WriteLine(string.Format("Creating RenderTargetTexture ({0}x{1} {2})..", parameters.width, parameters.height, parameters.format.ToString()));

            this.BuildRenderTargetTexture(parameters.width, parameters.height, parameters.format, parameters.multiSampleCount, parameters.multiSampleQuality);
        }

        protected void BuildRenderTargetTexture(int width, int height, SlimDX.DXGI.Format format, int multiSampleCount, int multiSampleQuality)
        {
            if (this.Texture != null &&
                width == this.RenderTargetWidth &&
		        height == this.RenderTargetHeight &&
		        format == this.RenderTargetFormat &&
		        this.multiSampleCount == multiSampleCount &&
		        this.multiSampleQuality == multiSampleQuality)
	        {
		        return;
	        }

            this.DisposeInternal();

	        // get missing information
	        if (multiSampleCount == 0)
		        multiSampleCount = 1;
	        if (width == 0)
		        width = 1;
	        if (height == 0)
		        height = 1;
	        if (format == SlimDX.DXGI.Format.Unknown)
		        format = SlimDX.DXGI.Format.R8G8B8A8_UNorm;

            this.multiSampleCount = multiSampleCount;
	        this.multiSampleQuality = multiSampleQuality;

            if (this.Texture == null)
                this.Texture = new Texture(new EmptyTextureParams()
                    {
                        Width = width,
                        Height = height,
                        Elements = 1,
                        MipLevels = 0,
                        Format = format,
                        AccessType = SlimDX.Direct3D10.ResourceUsage.Staging,
                        RenderTarget = true,
                        MultiSampleCount = multiSampleCount,
                        MultiSampleQuality = multiSampleQuality
                    });
            else if (this.Texture is Texture)
	            ((Texture)this.Texture).CreateRenderTargetTexture(width, height, format, multiSampleCount, multiSampleQuality);

            this.DX10RenderTargetView = new SlimDX.Direct3D10.RenderTargetView(Engine.Device, this.Texture.Texture2D);

            this.ViewPort = new ViewPort()
            {
                Width = width,
                Height = height
            };
        }

        public override int RenderTargetWidth
        {
            get { return Texture.TextureWidth; }
        }

        public override int RenderTargetHeight
        {
            get { return Texture.TextureHeight; }
        }

        public override SlimDX.DXGI.Format RenderTargetFormat
        {
            get { return Texture.TextureFormat; }
        }

        #region IRenderTargetTexture Members

        public void Resize(int width, int height)
        {
            if (this.RenderTargetWidth == width || this.RenderTargetHeight == height)
                return;

            var usedDepthStencilBuffer = this.HasDepthStencilBuffer;
            this.BuildRenderTargetTexture(width, height, RenderTargetFormat, multiSampleCount, multiSampleQuality);
            this.HasDepthStencilBuffer = usedDepthStencilBuffer;
        }

        public Texture Texture { get; protected set; }

        #endregion

        private ICreationParams creationParams;
        public override ICreationParams CreationParams
        {
            get { return creationParams; }
        }

        private ObservableCollection<IResource> children;
        [ReadOnly]
        public override ObservableCollection<IResource> Children
        {
            get
            {
                if (children == null)
                {
                    children = new ObservableCollection<IResource>();
                    children.Add(Texture);
                }
                return children;
            }
        }
    }
}