//
// Copyright (c) 2008-2015 the Urho3D project.
// Copyright (c) 2015 Xamarin Inc
// Copyright (c) 2016 THUNDERBEAST GAMES LLC
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
using AtomicEngine;

namespace FeatureExamples
{
	public class RenderToTextureSample : Sample
	{
		Scene rttScene;
		Node rttCameraNode;

		public RenderToTextureSample() : base() { }

        public override void Start()
        {
			base.Start();
			CreateScene();
			SimpleCreateInstructionsWithWasd();
			SetupViewport();
		}

        override protected void Stop()
        {
            if (rttScene != null)
                rttScene.Dispose();
        }


        protected override void Update(float timeStep)
        {
			base.Update(timeStep);
			SimpleMoveCamera3D(timeStep);
		}

		void SetupViewport()
		{
			var renderer = GetSubsystem<Renderer>();
			renderer.SetViewport(0, new Viewport( scene, CameraNode.GetComponent<Camera>()));
		}

		void CreateScene()
		{
			var cache = GetSubsystem<ResourceCache>();

			{
				rttScene = new Scene();
				// Create octree, use default volume (-1000, -1000, -1000) to (1000, 1000, 1000)
				rttScene.CreateComponent<Octree>();

				// Create a Zone for ambient light & fog control
				Node zoneNode = rttScene.CreateChild("Zone");
				Zone zone = zoneNode.CreateComponent<Zone>();
				// Set same volume as the Octree, set a close bluish fog and some ambient light
				zone.SetBoundingBox(new BoundingBox(-1000.0f, 1000.0f));
				zone.AmbientColor = new Color(0.05f, 0.1f, 0.15f);
				zone.FogColor = new Color(0.1f, 0.2f, 0.3f);
				zone.FogStart = 10.0f;
				zone.FogEnd = 100.0f;

				// Create randomly positioned and oriented box StaticModels in the scene
				const uint numObjects = 2000;
				for (uint i = 0; i < numObjects; ++i)
				{
					Node boxNode = rttScene.CreateChild("Box");
					boxNode.Position = new Vector3(NextRandom(200.0f) - 100.0f, NextRandom(200.0f) - 100.0f,
						NextRandom(200.0f) - 100.0f);
					// Orient using random pitch, yaw and roll Euler angles
					boxNode.Rotation = new Quaternion(NextRandom(360.0f), NextRandom(360.0f), NextRandom(360.0f));
					StaticModel boxObject = boxNode.CreateComponent<StaticModel>();
					boxObject.Model = cache.Get<Model>("Models/Box.mdl");
					boxObject.SetMaterial(cache.Get<Material>("Materials/Stone.xml"));

					// Add our custom Rotator component which will rotate the scene node each frame, when the scene sends its update event.
					// Simply set same rotation speed for all objects
					Rotator rotator = new Rotator();
					boxNode.AddComponent(rotator);
					rotator.SetRotationSpeed(new Vector3(10.0f, 20.0f, 30.0f));
				}

				// Create a camera for the render-to-texture scene. Simply leave it at the world origin and let it observe the scene
				rttCameraNode = rttScene.CreateChild("Camera");
				Camera camera = rttCameraNode.CreateComponent<Camera>();
				camera.FarClip = 100.0f;

				// Create a point light to the camera scene node
				Light light = rttCameraNode.CreateComponent<Light>();
				light.LightType = LightType.LIGHT_POINT;
				light.Range = 30.0f;
			}

			{
				// Create the scene in which we move around

				scene = new Scene();

				// Create octree, use also default volume (-1000, -1000, -1000) to (1000, 1000, 1000)
				scene.CreateComponent<Octree>();

				// Create a Zone component for ambient lighting & fog control
				Node zoneNode = scene.CreateChild("Zone");
				Zone zone = zoneNode.CreateComponent<Zone>();
				zone.SetBoundingBox(new BoundingBox(-1000.0f, 1000.0f));
				zone.AmbientColor = new Color(0.1f, 0.1f, 0.1f);
				zone.FogStart = 100.0f;
				zone.FogEnd = 300.0f;

				// Create a directional light without shadows
				Node lightNode = scene.CreateChild("DirectionalLight");
				lightNode.SetDirection(new Vector3(0.5f, -1.0f, 0.5f));
				Light light = lightNode.CreateComponent<Light>();
				light.LightType = LightType.LIGHT_DIRECTIONAL;
				light.Color = new Color(0.2f, 0.2f, 0.2f);
				light.SpecularIntensity = 1.0f;

				// Create a "floor" consisting of several tiles
				for (int y = -5; y <= 5; ++y)
				{
					for (int x = -5; x <= 5; ++x)
					{
						Node floorNode = scene.CreateChild("FloorTile");
						floorNode.Position = new Vector3(x*20.5f, -0.5f, y*20.5f);
						floorNode.Scale = new Vector3(20.0f, 1.0f, 20.0f);
						StaticModel floorObject = floorNode.CreateComponent<StaticModel>();
						floorObject.Model = cache.Get<Model>("Models/Box.mdl");
						floorObject.SetMaterial(cache.Get<Material>("Materials/Stone.xml"));
					}
				}

				// Create a "screen" like object for viewing the second scene. Construct it from two StaticModels, a box for the frame
				// and a plane for the actual view
				{
					Node boxNode = scene.CreateChild("ScreenBox");
					boxNode.Position = new Vector3(0.0f, 10.0f, 0.0f);
					boxNode.Scale = new Vector3(21.0f, 16.0f, 0.5f);
					StaticModel boxObject = boxNode.CreateComponent<StaticModel>();
					boxObject.Model = cache.Get<Model>("Models/Box.mdl");
					boxObject.SetMaterial(cache.Get<Material>("Materials/Stone.xml"));

					Node screenNode = scene.CreateChild("Screen");
					screenNode.Position = new Vector3(0.0f, 10.0f, -0.27f);
					screenNode.Rotation = new Quaternion(-90.0f, 0.0f, 0.0f);
					screenNode.Scale = new Vector3(20.0f, 0.0f, 15.0f);
					StaticModel screenObject = screenNode.CreateComponent<StaticModel>();
					screenObject.Model = cache.Get<Model>("Models/Plane.mdl");

					// Create a renderable texture (1024x768, RGB format), enable bilinear filtering on it
					Texture2D renderTexture = new Texture2D();
					renderTexture.SetSize(1024, 768, Graphics.GetRGBFormat(), TextureUsage.TEXTURE_RENDERTARGET);
					renderTexture.FilterMode = TextureFilterMode.FILTER_BILINEAR;

					// Create a new material from scratch, use the diffuse unlit technique, assign the render texture
					// as its diffuse texture, then assign the material to the screen plane object
					Material renderMaterial = new Material();
					renderMaterial.SetTechnique(0, cache.Get<Technique>("Techniques/DiffUnlit.xml"), 0, 0);
					renderMaterial.SetTexture(TextureUnit.TU_DIFFUSE, renderTexture);
					screenObject.SetMaterial(renderMaterial);

					// Get the texture's RenderSurface object (exists when the texture has been created in rendertarget mode)
					// and define the viewport for rendering the second scene, similarly as how backbuffer viewports are defined
					// to the Renderer subsystem. By default the texture viewport will be updated when the texture is visible
					// in the main view
					RenderSurface surface = renderTexture.RenderSurface;
					Viewport rttViewport = new Viewport(rttScene, rttCameraNode.GetComponent<Camera>());
					surface.SetViewport(0, rttViewport);
				}


				// Create the camera. Limit far clip distance to match the fog
				CameraNode = scene.CreateChild("Camera");
				var camera = CameraNode.CreateComponent<Camera>();
				camera.FarClip = 300.0f;
				// Set an initial position for the camera scene node above the plane
				CameraNode.Position = new Vector3(0.0f, 7.0f, -30.0f);
			}
		}

        public class Rotator : CSComponent
        {
            Vector3 rotationSpeed;

            public void SetRotationSpeed(Vector3 vector)
            {
                rotationSpeed = vector;
            }

            void Update(float timeStep)
            {
                Node.Rotate(new Quaternion(rotationSpeed.X * timeStep, rotationSpeed.Y * timeStep, rotationSpeed.Z * timeStep), TransformSpace.TS_LOCAL);
            }
        }

    }

}