using System;
using System.Collections.Generic;
using System.Linq;

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;

using XnaCommons.Core;
using XnaCommons.Rendering;

using XnaGUI.Controls;
using XnaGUI.Controls.Decorators;

using eyecm.PhysX;

namespace PhysXTest
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class MainGame : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics;
        Camera camera;
        SpriteFont consolas;
        Model rails, wheel;

        Model boxModel;

        float x = 0;

        VertexPositionColorNormal[] vpc;
        BasicEffect effect;


        public MainGame()
        {
            graphics = new GraphicsDeviceManager(this);
            graphics.PreferMultiSampling = true;
            Content.RootDirectory = "Content";
            Components.Add(camera = new Camera(this) { FarPlane = 50000 });
            Components.Add(new ResourceManager(this));
        }


        Physics physics;
        Scene scene;

        Actor groundPlane, box;

        void CreateActorFromMesh(Model model)
        {
            Dictionary<string, object> modelDict = model.Tag as Dictionary<string, object>;
            Vector3[] verts = modelDict["Vertices"] as Vector3[];

            ConvexMeshDesc convexDesk = new ConvexMeshDesc();
            convexDesk.PinPoints<Vector3>(verts, 0, 0);
        }

        Actor CreateGroundPlane()
        {
            ActorDesc actorDesc = new ActorDesc();
            actorDesc.Shapes.Add(new PlaneShapeDesc());
            return scene.CreateActor(actorDesc);
        }

        Actor CreateBox()
        {
            ActorDesc actorDesc = new ActorDesc();
            BoxShapeDesc boxDesc = new BoxShapeDesc();
            float radius = boxModel.Meshes[0].BoundingSphere.Radius / 2;
            boxDesc.Dimensions = new Vector3(radius, radius, radius);
            actorDesc.Shapes.Add(boxDesc);

            actorDesc.Body = new BodyDesc();
            actorDesc.Density = 10;
            actorDesc.GlobalPose = Matrix.CreateFromYawPitchRoll(0.25f, 0.35f, 0.7f) * Matrix.CreateTranslation(10, 40.5f, 0);
            return scene.CreateActor(actorDesc);
        }

        private void InitPhysics()
        {
            physics = Physics.Create();
            SceneDesc sceneDesc = new SceneDesc() { Gravity = new Vector3(0, -9.8f, 0) };
            scene = physics.CreateScene(sceneDesc);

            physics.Parameters.SkinWidth = 0.01f;
            physics.Parameters.VisualizationScale = 1;
            physics.Parameters.VisualizeCollisionShapes = 1;

            Material defaultMaterial = scene.Materials[0];
            defaultMaterial.Restitution = 0.5f;
            defaultMaterial.StaticFriction = 0.5f;
            defaultMaterial.DynamicFriction = 0.4f;

            box = CreateBox();
            groundPlane = CreateGroundPlane();

            ProcessPhysics(0.01f);
        }

        private void ProcessPhysics(float dt)
        {
            scene.Simulate(dt);
            scene.FlushStream();
        }

        private void GetPhysicsResults()
        {
            while (!scene.FetchResults(SimulationStatuses.AllFinished, false)) ;
        }

        protected override void Initialize()
        {
            base.Initialize();
            Window.Title = "PhysX Test";
        }

        VertexBuffer vBuffer;

        protected override void LoadContent()
        {
            consolas = Content.Load<SpriteFont>("Fonts\\Calibri_12");
            rails = Content.Load<Model>("Models\\Rails\\railway");
            wheel = Content.Load<Model>("Models\\Wheel\\wheelpair");
            boxModel = Content.Load<Model>("Models\\Basic\\box");
            InitPhysics();

            vpc = new VertexPositionColorNormal[6];
            vpc[0] = new VertexPositionColorNormal(new Vector3(0.5f, 0, 0.5f), Color.LightGray);
            vpc[1] = new VertexPositionColorNormal(new Vector3(-0.5f, 0, 0.5f), Color.Gray);
            vpc[2] = new VertexPositionColorNormal(new Vector3(-0.5f, 0, -0.5f), Color.DarkGray);

            vpc[3] = new VertexPositionColorNormal(new Vector3(-0.5f, 0, -0.5f), Color.DarkGray);
            vpc[4] = new VertexPositionColorNormal(new Vector3(0.5f, 0, -0.5f), Color.LightGray);
            vpc[5] = new VertexPositionColorNormal(new Vector3(0.5f, 0, 0.5f), Color.LightGray);

            vBuffer = new VertexBuffer(GraphicsDevice, VertexPositionColorNormal.vdecl, 6, BufferUsage.WriteOnly);
            vBuffer.SetData<VertexPositionColorNormal>(vpc);
            effect = new BasicEffect(GraphicsDevice);
        }

        protected override void UnloadContent()
        {
        }

        protected override void Update(GameTime gameTime)
        {
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
                this.Exit();
            base.Update(gameTime);

            if (Keyboard.GetState().IsKeyDown(Keys.Up))
                box.AddForce(new Vector3(0, 40.0f, 0), ForceModes.Acceleration, true);
            if (Keyboard.GetState().IsKeyDown(Keys.Down))
                box.AddForce(new Vector3(0, -40, 0), ForceModes.Acceleration, true);
            if (Keyboard.GetState().IsKeyDown(Keys.Left))
                box.AddForce(new Vector3(-40, 0, 0), ForceModes.Acceleration, true);
            if (Keyboard.GetState().IsKeyDown(Keys.Right))
                box.AddForce(new Vector3(40, 0, 0), ForceModes.Acceleration, true);


            GetPhysicsResults();
            ProcessPhysics((float)gameTime.ElapsedGameTime.TotalSeconds);

        }


        private void DrawPlane()
        {
            effect.World = Matrix.CreateScale(5000);
            effect.View = camera.View;
            effect.Projection = camera.Projection;
            effect.EnableDefaultLighting();
            effect.VertexColorEnabled = true;
            effect.PreferPerPixelLighting = true;
            GraphicsDevice.SetVertexBuffer(vBuffer);
            foreach (EffectPass pass in effect.CurrentTechnique.Passes)
            {
                pass.Apply();
                GraphicsDevice.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);
            }
        }

        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice.DepthStencilState = new DepthStencilState();
            GraphicsDevice.Clear(Color.CornflowerBlue);


            BasicEffectRenderer.DrawModel(rails, Matrix.Identity, camera);
            BasicEffectRenderer.DrawModel(wheel, Matrix.CreateRotationX(x / Microsoft.Xna.Framework.MathHelper.Pi) * Matrix.CreateTranslation(0, 4.8f, x), camera);
            BasicEffectRenderer.DrawModel(boxModel, box.GlobalPose, camera);

            DrawPlane();
            //rails.Draw(Matrix.Identity, camera.View, camera.Projection);

            base.Draw(gameTime);
        }


    }
}