Images.cs

/* Copyright (C) 2021 Dylan Cheng (https://github.com/newlooper)

This file is part of VirtualSpace.

VirtualSpace is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

VirtualSpace is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with VirtualSpace. If not, see <https://www.gnu.org/licenses/>.
*/

using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Text.RegularExpressions;
using VirtualSpace.AppLogs;

namespace VirtualSpace.Helpers
{
    internal static class PathInfo
    {
        public const string WIDTH_HEIGHT_SPLITTER = "x";
    }

    public static class Images
    {
        public static Bitmap GetScaledBitmap( int width, int height, string path, ref Wallpaper wp, string cachePath, long quality )
        {
            var cached = Wallpaper.CachedWallPaper( path, cachePath, width, height );

            if ( cached != null ) return cached;
            using ( var src = new Bitmap( path ) )
            {
                var dest = new Bitmap( width, height, PixelFormat.Format32bppPArgb );
                using ( var gr = Graphics.FromImage( dest ) )
                {
                    gr.DrawImage( src, new Rectangle( Point.Empty, dest.Size ) );
                }

                var md5Path = Wallpaper.Md5Hash( path );
                var file = Path.Combine( cachePath, md5Path.Str0, md5Path.Str1, width + PathInfo.WIDTH_HEIGHT_SPLITTER + height,
                    md5Path.FullString + "_" + Environment.CurrentManagedThreadId );

                // dest.Save( file, ImageFormat.Jpeg );

                var jpgEncoder        = GetEncoder( ImageFormat.Jpeg );
                var encoder           = System.Drawing.Imaging.Encoder.Quality;
                var encoderParameters = new EncoderParameters( 1 );
                var encoderParameter  = new EncoderParameter( encoder, quality );
                encoderParameters.Param[0] = encoderParameter;
                dest.Save( file, jpgEncoder, encoderParameters );

                wp.Fullpath = file;

                return dest;
            }
        }

        private static ImageCodecInfo GetEncoder( ImageFormat format )
        {
            var codecs = ImageCodecInfo.GetImageEncoders();
            foreach ( var codec in codecs )
            {
                if ( codec.FormatID == format.Guid )
                {
                    return codec;
                }
            }

            return null;
        }

        public static Icon BytesToIcon( object bytes )
        {
            using var ms = new MemoryStream( (byte[])bytes );
            return new Icon( ms );
        }

        public static Bitmap BytesToBitmap( object bytes )
        {
            using var ms = new MemoryStream( (byte[])bytes );
            return new Bitmap( ms );
        }
    }

    public class Wallpaper
    {
        public Bitmap? Image    { get; set; }
        public Color   Color    { get; set; }
        public string? Fullpath { get; set; }

        public static Bitmap? CachedWallPaper( string path, string cachePath, int width, int height )
        {
            var cached = CachedWallPaperInfo( path, cachePath, width, height );
            return cached.Exists ? new Bitmap( cached.Path ) : null;
        }

        public static (bool Exists, string Path) CachedWallPaperInfo( string path, string cachePath, int width, int height )
        {
            var md5Path    = Md5Hash( path );
            var targetPath = Path.Combine( cachePath, md5Path.Str0, md5Path.Str1, width + PathInfo.WIDTH_HEIGHT_SPLITTER + height );
            Directory.CreateDirectory( targetPath );
            var filepath = Path.Combine( targetPath, md5Path.FullString );

            return new ValueTuple<bool, string>( File.Exists( filepath ), filepath );
        }

        public static (string FullString, string Str0, string Str1) Md5Hash( string input )
        {
            var md5        = MD5.Create();
            var inputBytes = Encoding.ASCII.GetBytes( input );
            var hashBytes  = md5.ComputeHash( inputBytes );

            var sb = new StringBuilder();
            foreach ( var b in hashBytes )
            {
                sb.Append( b.ToString( "x2" ) );
            }

            var md5Str = sb.ToString();

            return new ValueTuple<string, string, string>(
                md5Str,
                md5Str.Substring( 0, 1 ),
                md5Str.Substring( 1, 1 )
            );
        }

        public void Release()
        {
            Image?.Dispose();
            Image = null;
            if ( string.IsNullOrEmpty( Fullpath ) ) return;
            try
            {
                var file = Regex.Replace( Fullpath, @"(.*?)_\d+$", "$1" );
                if ( !File.Exists( file ) )
                    File.Move( Fullpath, file );
            }
            catch ( Exception ex )
            {
                Logger.Warning( "Delete cache file: " + ex.Message );
            }
            finally
            {
                File.Delete( Fullpath );
            }
        }
    }
}