using System;
using System.Diagnostics;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;

namespace BouncyCatIsBouncy
{
    
    class Cat : IDynamicObject
    {
        public delegate void EventHandler();
        public event EventHandler OnLaunch;
        public event EventHandler OnDeath;
        SpriteBatch m_batch;
        bool m_launched;
        public bool Launched { get { return m_launched; } }
        public bool Dead { get; private set; }
        PhysicsBody m_body;
        Animation m_animation;
        RandomCatSounds m_catSounds;
        SoundEffect m_cannonBlast;
        Random m_rand = new Random();
        float m_rotationAmount;
        float m_launchDelay = 2000.0f;

        const int CAT_SIZE = 80;

        public Vector2 Position 
        { 
            get { return m_body.Position; }
            set { m_animation.Center = m_body.Position = value; }
        }

        public Cat(SpriteBatch batch, Physics simulator)
        {
            Debug.Assert(batch != null);
            m_batch = batch;

            
            m_body = new PhysicsBody();
            m_body.CoeffRestitution = .95f;
            m_body.OnCollision += OnCollision;

            var geom = new PhysicsGeom(m_body, new RadialBB(CAT_SIZE / 2.0f));

            simulator.SetPrimary(m_body);
        }

        public void Update(float dt)
        {
            if (Dead)
                return;

            m_animation.Update(dt);
            m_animation.Rotation += m_rotationAmount * dt;
            m_animation.Center = m_body.Position;
            if (m_launched)
            {
                if (m_launchDelay > 0.0f)
                {
                    m_launchDelay -= dt;
                    if (m_launchDelay <= 0.0f)
                    {
                        m_body.ApplyImpulse(m_launchNormal * 1.3f);
                        m_body.Gravity = new Vector2(0, .00025f);
                        m_cannonBlast.Play();
                    }
                }
                else
                {
                    CheckVelocity(dt);
                }
            }
        }

        const float TIME_BEFORE_DEAD = 1000.0f;
        float m_timeSinceMovement = TIME_BEFORE_DEAD;
        private void CheckVelocity(float dt)
        {
            if (m_body.Velocity.LengthSquared() < .01f)
            {
                m_timeSinceMovement -= dt;
                if (m_timeSinceMovement < 0.0f)
                {
                    m_body.Velocity = m_body.Gravity = Vector2.Zero;
                    Dead = true;
                    if (OnDeath != null)
                        OnDeath();
                }
                
            }
            else
            {
                m_timeSinceMovement = TIME_BEFORE_DEAD;
            }
        }

        Vector2 m_launchNormal;
        public void Launch(Vector2 normal)
        {
            if (!m_launched)
            {
                m_launchNormal = normal;


                m_launched = true;
                if (OnLaunch != null)
                    OnLaunch();

                m_animation.Animating = true;

                ApplyRotation();
            }
        }

        private void OnCollision(PhysicsBody otherBody)
        {
            if (Dead)
                return;
            ApplyRotation();
            if (otherBody.CollisionResponseEnable && m_rand.NextDouble() > .85)
            {
                m_catSounds.Play();
            }
        }

        private void ApplyRotation()
        {
            m_rotationAmount = (float)(m_rand.NextDouble() - .5) / 50.0f;
        }

        public void Draw()
        {
            if (m_launchDelay <= 0.0f)
                m_animation.Draw();

            Debugging.RadialBBRenderer.Draw(m_batch, (RadialBB)m_body.Geometry[0].Bounding);
            Debugging.DrawVector.Draw(m_batch, m_body.Position, m_body.Position + m_body.Velocity * 100, Color.Green);
        }

        public void LoadContent(ContentManager manager)
        {
            m_animation = new Animation(m_batch, manager.Load<Texture2D>(@"Spritesheets/mittens"), 256, 256);
            m_animation.Height = m_animation.Width = CAT_SIZE;
            m_catSounds = new RandomCatSounds(manager);
            m_cannonBlast = manager.Load<SoundEffect>(@"Sounds/Misc/cannonlaunch");
        }



    }
}