/*
 * Meteor.cs
 * Authors:     August Zinsser
 * 
 * Copyright Matthew Belmonte 2007
 */


using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Storage;
using tAC_Engine;


namespace Astropolis
{
    /// <summary>
    /// Represents the flying meteors in Meteor Madness.
    /// The player can shoot them, and they explode.
    /// Meteors can also crash into the player, causing it damage
    /// </summary>
    class Meteor : Entity
    {
        private static Animation[] mMeteorSprites;

        private float mSpawnDepth;      // How far away (along the z-axis) from the player that the meteors spawn at
        private float mKillDepth;       // The z-depth where the meteors should kill themselves (which should be behind the player and off camera)
        private bool mAlive = true;     // If the meteor is alive or not
        private Vector3 mSpace3DSize;   // Size of this entity in space3D coordinates

        public float SpawnDepth { get { return mSpawnDepth; } }
        public float KillDepth { set { mKillDepth = value; } get { return mKillDepth; } }
        public bool Alive { set { mAlive = value; } get { return mAlive; } }
        public override float Width { set { mSpace3DSize.X = value; } get { return mSpace3DSize.X; } }
        public override float Height { set { mSpace3DSize.Y = value; } get { return mSpace3DSize.Y; } }
        public override Vector3 Size { get { return mSpace3DSize; } }


        /// <summary>
        /// Constructor
        /// </summary>
        /// <param name="width">In Space3D units</param>
        /// <param name="height">In Spacce3D units</param>
        /// <param name="depth">In Spacce3D units</param>
        /// <param name="speed">Space3D units/second</param>
        /// <param name="spawnDepth">Space3D depth to spawn meteors</param>
        /// <param name="killDepth">Space3D depth to kill meteors</param>
        public Meteor(float width, float height, float depth, float speed, float spawnDepth, float killDepth)
            : base()
        {
            // Load the meteor sprite sheet
            if (mMeteorSprites == null)
            {
                mMeteorSprites = new Animation[4];
                Texture2D spriteSheet = TextureManager.Load(@"content\MiniGames\Meteors");
                for (int i = 0; i < mMeteorSprites.Length; i++)
                {
                    mMeteorSprites[i] = new Animation(new Vector2(spriteSheet.Width / 2, spriteSheet.Height / 2));
                    mMeteorSprites[i].AddClip("Default", spriteSheet, 1, i, 1f);
                    mMeteorSprites[i].Play("Default");
                }
            }

            double p = GenericBaseApplication.GameManager.RandomNumber();
            if (p < .3333)
                mSprite = mMeteorSprites[0];
            else if (p < .6667)
                mSprite = mMeteorSprites[1];
            else
                mSprite = mMeteorSprites[2];
                        
            mSpace3DSize = new Vector3(width, height, depth);
            mVel.Z = -1 * speed;
            mSpawnDepth = spawnDepth;
            mKillDepth = killDepth;
            mAngVel = (spawnDepth + 3) * (2 * GenericBaseApplication.GameManager.RandomNumber() - 1);
            double ArcPosition = Math.PI * 2 * GenericBaseApplication.GameManager.RandomNumber();
            Vector2 PositionFromOrigin = new Vector2((float)Math.Cos(ArcPosition), (float)Math.Sin(ArcPosition));
            mPos.X = .8F * PositionFromOrigin.X;
            mPos.Y = .8F * PositionFromOrigin.Y;
            mPos.Z = spawnDepth;
            mSize.Z = width;
        }


        /// <summary>
        /// Scrolls the meteor towards the player
        /// </summary>
        public override void Update()
        {
            base.Update();

            // Kill the meteor if it has scrolled past the player
            if (mPos.Z < mKillDepth)
            {
                mAlive = false;
            }
        }
    }
}