using System;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using System.Collections.Generic;

namespace WindowsGame1
{
    class Emitter
    {
        Texture2D Texture;
        public bool Active;
        public int Density;
        public Vector2 Position;
        public int Life;
        TimeSpan timeCreated;
        TimeSpan timeToLive;
        public float Gravity;
        public float yvel;
        public Particle particle;
        List<Particle> particles;
        Random Randomnum;
        float Direction;
        Vector2 InitialVel;


        public void Initialize(Texture2D texture, Vector2 position,int density,int life,GameTime gameTime, float gravity)
        {

            particles = new List<Particle>();
            Texture = texture;
            Active = true;
            Position = position;
            Density = density;
            Life = life;
            timeCreated = gameTime.TotalGameTime;
            timeToLive = TimeSpan.FromSeconds(Life);
            Gravity = gravity;
            yvel = 0;


            AddParticle();





        }
        public void AddParticle()
        {
            for (int i = 0; i < Density; i++)
            {
            particle = new Particle();
            Randomnum = new Random();
            Direction = Randomnum.Next(360);
            InitialVel = AngleToVector(Direction);
            particle.Initialize(Texture, Position, 10, 2, InitialVel);
            particles.Add(particle);
            }
        }

        Vector2 AngleToVector(float angle)
        {
            return new Vector2((float)Math.Cos(angle), (float)Math.Sin(angle));
        }
        public void Update(GameTime gameTime)
        {
            if (gameTime.TotalGameTime - timeCreated > timeToLive)
            {
                Active = false;
                Position = Vector2.Zero;

            }

            else
            {
                yvel += Gravity;
                Position.Y += yvel;
            }
            UpdateParticles(gameTime);
        }
        public void UpdateParticles(GameTime gameTime)
        {
            for (int i = 0; i < particles.Count; i++)
            {
                particles[i].Update(gameTime);
            }
        }
        public void Draw(SpriteBatch spriteBatch)
        {
            for (int i = 0; i < particles.Count; i++)
            {
                particles[i].Draw(spriteBatch);
            }
            spriteBatch.Draw(Texture,Position,Color.White);
        }
    }
}