using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;

namespace BouncyCatIsBouncy
{
    class Animation : IDrawable, IUpdateable
    {
        SpriteBatch m_batch;
        Texture2D m_sheet;
        int m_cellWidth, m_cellHeight;
        int m_xCell, m_yCell;
        float m_timeBeforeFlip;
        

        public float Speed { get; set; }
        public float Rotation { get; set; }
        public Vector2 Center { get; set; }
        public int Width { get; set; }
        public int Height { get; set; }
        public bool Animating { get; set; }
        public int Padding { get; set; }
        public bool StopAtEnd { get; set; }

        public Animation(SpriteBatch batch, Texture2D sheet, int cellWidth, int cellHeight)
        {
            m_timeBeforeFlip = Speed = 100f;
            m_batch = batch;
            m_sheet = sheet;

            Width = m_cellWidth = cellWidth;
            Height = m_cellHeight = cellHeight;
        }

        public void Update(float dt)
        {
            if (!Animating)
                return;

            m_timeBeforeFlip -= dt;
            if (m_timeBeforeFlip < 0.0f)
            {
                m_timeBeforeFlip += Speed;

                m_xCell++;
                if (m_xCell * (m_cellWidth + Padding) >= m_sheet.Width)
                {
                    m_xCell = 0;
                    m_yCell++;
                    if (m_yCell * (m_cellHeight + Padding) >= m_sheet.Height)
                    {
                        m_yCell = 0;
                        Animating = !StopAtEnd;
                    }
                }
            }
        }

        public void Draw()
        {
            m_batch.Draw(m_sheet, new Rectangle((int)Center.X, (int)Center.Y, Width, Height),
                new Rectangle(m_xCell * (m_cellWidth + Padding), m_yCell * (m_cellHeight + Padding), m_cellWidth + Padding, m_cellHeight + Padding), 
                Color.White, Rotation,
                new Vector2(m_cellWidth / 2, m_cellHeight / 2), SpriteEffects.None, 1.0f);
        }
    }
}