using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Tango.RemoteDesktop
{
    /// <summary>
    /// Represents a base <see cref="IFrameEncoder"/>.
    /// </summary>
    /// <seealso cref="Tango.RemoteDesktop.IFrameEncoder" />
    public abstract class FrameEncoder : IFrameEncoder
    {
        /// <summary>
        /// Gets the frame instance.
        /// </summary>
        public IFrame Frame { get; private set; }

        /// <summary>
        /// Initializes a new instance of the <see cref="FrameEncoder"/> class using an existing <see cref="IFrame"/>.
        /// </summary>
        /// <param name="frame">The frame.</param>
        public FrameEncoder(IFrame frame)
        {
            Frame = frame;
        }

        /// <summary>
        /// Returns a stream containing the encoded frame.
        /// </summary>
        /// <returns></returns>
        public abstract MemoryStream ToStream();

        /// <summary>
        /// Returns a byte array containing the encoded frame.
        /// </summary>
        /// <returns></returns>
        public virtual byte[] ToArray()
        {
            using (var ms = ToStream())
            {
                return ms.ToArray();
            }
        }

        /// <summary>
        /// Gets the image encoder by the specified image format.
        /// </summary>
        /// <param name="format">The format.</param>
        /// <returns></returns>
        protected ImageCodecInfo GetEncoder(ImageFormat format)
        {
            ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
            return codecs.Single(codec => codec.FormatID == format.Guid);
        }
    }
}