using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;

namespace RBG_Server
{
    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : Application
    {
        public static App Context { get; private set; }
        public GameServer BoardGameServer {get;}
        public CommunicationHandler GameCommunicationHandler { get; private set;}

        protected static readonly SolidColorBrush RED_BRUSH = new(Color.FromRgb(255, 0, 0));
        protected static readonly SolidColorBrush BLUE_BRUSH = new(Color.FromRgb(0, 0, 255));
        protected static readonly SolidColorBrush GREEN_BRUSH = new(Color.FromRgb(0, 255, 0));

        public const string MIP_LOW = "_mip_low";
        public const string MIP_MEDIUM = "_mip_med";
        public const string MIP_HIGH = "_mip_high";
        public const string MIP_RAW = "_mip_raw";

        /// <summary>
        /// Loads the specified files from disk, creating mip maps as appropriate
        /// </summary>
        /// <param name="selectedFiles"></param>
        /// <param name="isSprite"></param>
        /// <param name="spriteLimit"></param>
        void LoadFiles(string[] selectedFiles, bool isSprite=false, int spriteLimit=128)
        {
            // Continue in parallel
            _ = Parallel.ForEach(selectedFiles, (file) =>
            {
                LoadFile(file);
            });
        }
        /// <summary>
        /// Loads a singular file from disk, generating Mip maps as required
        /// </summary>
        /// <param name="path"></param>
        void LoadFile(string path, bool isSprite=true)
        {
            // Check if the file is a .gif, first.
            using FileStream fs = File.OpenRead(path);
            LoadStream(fs, path, isSprite);
            
        }

        public void LoadStream(Stream source, string path, bool isSprite)
        {
            long srcStart = source.Position;
            byte[] vs = new byte[6]; // First 6 bytes is the gif specifier
            source.Read(vs, 0, 6);
            source.Position = srcStart;
            string magicNumber = Encoding.ASCII.GetString(vs);
            if (magicNumber == "GIF87a" || magicNumber == "GIF89a")
            {
                // Gif file, replace with a layered .png
                GifBitmapDecoder decoder = new(source, BitmapCreateOptions.None, BitmapCacheOption.Default);
                // Obtain each .gif frame
                BitmapFrame[] frames = new BitmapFrame[decoder.Frames.Count];
                decoder.Frames.CopyTo(frames, 0);
                // Get frame sizes
                int height = frames[0].PixelHeight;
                int width = frames[0].PixelWidth;
                // The lowest mip is static, using either the thumb or first frame
                if (decoder.Thumbnail != null)
                {
                    double scaleRate = 32 / (double)Math.Max(height, width);
                    MemoryStream ms = ScaleImage(decoder.Thumbnail, scaleRate);
                    _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_LOW + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                }
                else
                {
                    double scaleRate = 32 / (double)Math.Max(height, width);
                    MemoryStream ms = ScaleImage(frames[0], scaleRate);
                    _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_LOW + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                }
                // The remaining mips are animated
                if (width >= 128 || height >= 128)
                {
                    double scaleRate = 128 / (double)Math.Max(height, width);
                    MemoryStream ms = ScaleAnimatedImage(frames, scaleRate);
                    _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_MEDIUM + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                }
                if (width >= 512 || height >= 512)
                {
                    double scaleRate = 512 / (double)Math.Max(height, width);
                    MemoryStream ms = ScaleAnimatedImage(frames, scaleRate);
                    _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_HIGH + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                }
                if (width >= 512 || height >= 512)
                {
                    // Just re-encode the gif to .png
                    PngBitmapEncoder encoder = new();
                    foreach (BitmapFrame frame in frames)
                    {
                        encoder.Frames.Add(frame);
                    }
                    MemoryStream ms = new();
                    encoder.Save(ms);
                    _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_RAW + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                }

            }
            else
            {
                // Regular image file
                // Create the bitmap to get the current intrinsics
                BitmapImage bitmapImage = new();
                bitmapImage.BeginInit();
                bitmapImage.StreamSource = source;
                bitmapImage.CacheOption = BitmapCacheOption.None;
                bitmapImage.EndInit();
                int height = bitmapImage.PixelHeight;
                int width = bitmapImage.PixelWidth;

                // Behaviour depends on the required image
                if (isSprite)
                {
                    // Sprites should have a low mip-map, and the medium
                    // Low = 32*32
                    // Medium = 128*128
                    // High = 512*512 or image size if less than 1024
                    if (width >= 32 || height >= 32)
                    {
                        double scaleRate = 32 / (double)Math.Max(height, width);
                        MemoryStream ms = ScaleImage(bitmapImage, scaleRate);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_LOW + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                    if (width >= 128 || height >= 128)
                    {
                        double scaleRate = 128 / (double)Math.Max(height, width);
                        MemoryStream ms = ScaleImage(bitmapImage, scaleRate);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_MEDIUM + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                    if (width >= 512 || height >= 512)
                    {
                        double scaleRate = 512 / (double)Math.Max(height, width);
                        MemoryStream ms = ScaleImage(bitmapImage, scaleRate);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_HIGH + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                    if (width >= 512 || height >= 512)
                    {
                        MemoryStream ms = new();
                        source.CopyTo(ms);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_RAW + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                }
                else
                {
                    // Non-sprites should have a low mip-map, and the medium, but at a larger size than the sprites
                    // Low = 128*128
                    // Medium = 512*512
                    // High = 2048*2048
                    if (width >= 128 || height >= 128)
                    {
                        double scaleRate = 128 / (double)Math.Max(height, width);
                        MemoryStream ms = ScaleImage(bitmapImage, scaleRate);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_LOW + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                    if (width >= 512 || height >= 512)
                    {
                        double scaleRate = 512 / (double)Math.Max(height, width);
                        MemoryStream ms = ScaleImage(bitmapImage, scaleRate);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_MEDIUM + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                    if (width >= 2048 || height >= 2048)
                    {
                        double scaleRate = 2048 / (double)Math.Max(height, width);
                        MemoryStream ms = ScaleImage(bitmapImage, scaleRate);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_HIGH + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                    if (width >= 2048 || height >= 2048)
                    {
                        MemoryStream ms = new();
                        source.CopyTo(ms);
                        _ = GameCommunicationHandler.ImageCollection.TryAdd(Path.GetFileNameWithoutExtension(path) + MIP_RAW + Path.GetExtension(path), new CachedByteArray(ms.ToArray()));
                    }
                }
            }
        }

        MemoryStream ScaleImage(BitmapSource source, double scaleRate)
        {
            TransformedBitmap modified = new(source, new ScaleTransform(source.PixelWidth * scaleRate, source.PixelHeight * scaleRate));
            PngBitmapEncoder encoder = new();
            encoder.Frames.Add(BitmapFrame.Create(modified));
            MemoryStream ms = new();
            encoder.Save(ms);
            return ms;
        }

        MemoryStream ScaleAnimatedImage(BitmapFrame[] frames, double scaleRate)
        {
            PngBitmapEncoder encoder = new();
            foreach (BitmapFrame frame in frames)
            {
                TransformedBitmap modified = new(frame, new ScaleTransform(frame.PixelWidth * scaleRate, frame.PixelHeight * scaleRate));
                encoder.Frames.Add(BitmapFrame.Create(modified));
            }
            MemoryStream ms = new();
            encoder.Save(ms);
            return ms;
        }
    }
}