LocalEmojiFiles.cs

using System;
using System.IO;
using System.IO.Compression;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Waher.Content.Images;
using Waher.Runtime.Settings;
using Waher.Events;
 
namespace Waher.Content.Emoji.Emoji1
{
    public enum Emoji1SourceFileType
    {
        Png64,
 
        Png128,
 
        Png512,
 
        Svg
    }
 
    public delegate bool FileExistsHandler(string path);
 
    public delegate byte[] ReadAllBytesHandler(string path);
 
    public class Emoji1LocalFiles : IEmojiSource, IDisposable
    {
        private readonly Emoji1SourceFileType sourceFileType;
        private ManualResetEvent initialized = new ManualResetEvent(false);
        private readonly string zipFileName;
        private readonly string programDataFolder;
        private readonly string imageUrl;
        private readonly int width;
        private readonly int height;
 
        public Emoji1LocalFiles(Emoji1SourceFileType SourceFileType, int Width, int Height,
            string ZipFileName, string ProgramDataFolder)
            : this(SourceFileType, Width, Height, string.Empty, ZipFileName, ProgramDataFolder)
        {
        }
 
        public Emoji1LocalFiles(Emoji1SourceFileType SourceFileType, int Width, int Height, string ImageURL,
            string ZipFileName, string ProgramDataFolder)
        {
            this.sourceFileType = SourceFileType;
            this.width = Width;
            this.height = Height;
            this.imageUrl = ImageURL;
            this.zipFileName = ZipFileName;
            this.programDataFolder = ProgramDataFolder;
 
            try
            {
                DateTime TP = File.GetLastWriteTime(this.zipFileName);
 
                if (File.Exists(this.zipFileName) && RuntimeSettings.Get(this.zipFileName, DateTime.MinValue) != TP)
                {
                    if (!Directory.Exists(ProgramDataFolder))
                        Directory.CreateDirectory(ProgramDataFolder);
                    else
                    {
                        string Folder = Path.Combine(ProgramDataFolder, "Emoji1");
 
                        if (Directory.Exists(Folder))
                            Directory.Delete(Folder, true);
                    }
 
                    this.initialized = new ManualResetEvent(false);
 
                    Task.Run(this.Unpack);
                }
                else
                    this.initialized = new ManualResetEvent(true);
            }
            catch (Exception ex)
            {
                Log.Exception(ex);
            }
        }
 
        private async Task Unpack()
        {
            try
            {
                Log.Informational("Starting unpacking file.",
                    new KeyValuePair<string, object>("FileName", this.zipFileName),
                    new KeyValuePair<string, object>("Destination", this.programDataFolder));
 
                ZipFile.ExtractToDirectory(this.zipFileName, this.programDataFolder);
 
                DateTime TP = File.GetLastWriteTime(this.zipFileName);
                await RuntimeSettings.SetAsync(this.zipFileName, TP);
 
                try
                {
                    File.Delete(this.zipFileName);
                    Log.Informational("File unpacked and deleted.", new KeyValuePair<string, object>("FileName", this.zipFileName));
                }
                catch (Exception)
                {
                    Log.Informational("File unpacked.", new KeyValuePair<string, object>("FileName", this.zipFileName));
                }
            }
            catch (Exception ex)
            {
                Log.Exception(ex);
            }
            finally
            {
                this.initialized.Set();
            }
        }
 
        public bool WaitUntilInitialized(int TimeoutMilliseconds)
        {
            return this.initialized.WaitOne(TimeoutMilliseconds);
        }
 
        public Emoji1SourceFileType SourceFileType => this.sourceFileType;
 
        public int Width => this.width;
 
        public int Height => this.height;
 
        public bool EmojiSupported(EmojiInfo Emoji)
        {
            string FileName = this.GetFileName(Emoji);
            return File.Exists(FileName);
        }
 
        public string GetFileName(EmojiInfo Emoji)
        {
            switch (this.sourceFileType)
            {
                case Emoji1SourceFileType.Png64: return Path.Combine(this.programDataFolder, "Emoji1", ImageCodec.FileExtensionPng, "64x64", Emoji.FileName);
                case Emoji1SourceFileType.Png128: return Path.Combine(this.programDataFolder, "Emoji1", ImageCodec.FileExtensionPng, "128x128", Emoji.FileName);
                case Emoji1SourceFileType.Png512: return Path.Combine(this.programDataFolder, "Emoji1", ImageCodec.FileExtensionPng, "512x512", Emoji.FileName);
                case Emoji1SourceFileType.Svg:
                default:
                    string s = Emoji.FileName;
                    if (s.EndsWith("." + ImageCodec.FileExtensionPng))
                        s = s.Substring(0, s.Length - 3) + ImageCodec.FileExtensionSvg;
 
                    return Path.Combine(this.programDataFolder, "Emoji1", ImageCodec.FileExtensionSvg, s);
            }
        }
 
        public Task GenerateHTML(StringBuilder Output, EmojiInfo Emoji, bool EmbedImage)
        {
            return this.GenerateHTML(Output, Emoji, 1, EmbedImage);
        }
 
        public async Task GenerateHTML(StringBuilder Output, EmojiInfo Emoji, int Level, bool EmbedImage)
        {
            Output.Append("<img alt=\":");
            Output.Append(Encode(Emoji.Description));
            Output.Append(":\" title=\"");
            Output.Append(Encode(Emoji.ShortName));
            Output.Append("\" width=\"");
            Output.Append(this.CalcSize(this.width, Level).ToString());
            Output.Append("\" height=\"");
            Output.Append(this.CalcSize(this.height, Level).ToString());
            Output.Append("\" src=\"");
            Output.Append(Encode(await this.GetUrl(Emoji, EmbedImage)));
            Output.Append("\"/>");
        }
 
        public int CalcSize(int OrgSize, int Level)
        {
            while (Level > 1)
            {
                OrgSize = (OrgSize * 4) / 3;
                if (--Level == 1)
                    return OrgSize;
 
                OrgSize = (OrgSize * 3) / 2;
                Level--;
            }
 
            return OrgSize;
        }
 
        private static string Encode(string s)
        {
            if (s is null || s.IndexOfAny(specialCharacters) < 0)
                return s;
 
            return s.
                Replace("&", "&amp;").
                Replace("<", "&lt;").
                Replace(">", "&gt;").
                Replace("\"", "&quot;").
                Replace("'", "&apos;");
        }
 
        private static readonly char[] specialCharacters = new char[] { '<', '>', '&', '"', '\'' };
 
        public async Task<string> GetUrl(EmojiInfo Emoji, bool Embed)
        {
            if (Embed || string.IsNullOrEmpty(this.imageUrl))
            {
                StringBuilder Output = new StringBuilder();
 
                Output.Append("data:");
 
                if (this.sourceFileType == Emoji1SourceFileType.Svg)
                    Output.Append(ImageCodec.ContentTypeSvg);
                else
                    Output.Append(ImageCodec.ContentTypePng);
 
                Output.Append(";base64,");
 
                string FileName = this.GetFileName(Emoji);
                byte[] Data = await Resources.ReadAllBytesAsync(FileName);
 
                Output.Append(Convert.ToBase64String(Data));
 
                return Output.ToString();
            }
            else
            {
                string s = Emoji.FileName;
                if (this.sourceFileType == Emoji1SourceFileType.Svg && s.EndsWith("." + ImageCodec.FileExtensionPng))
                    s = s.Substring(0, s.Length - 3) + ImageCodec.FileExtensionSvg;
 
                return this.imageUrl.Replace("%FILENAME%", s);
            }
        }
 
        public Task<IImageSource> GetImageSource(EmojiInfo Emoji)
        {
            return this.GetImageSource(Emoji, 1);
        }
 
        public async Task<IImageSource> GetImageSource(EmojiInfo Emoji, int Level)
        {
            return new ImageSource()
            {
                Url = await this.GetUrl(Emoji, false),
                Width = this.CalcSize(this.width, Level),
                Height = this.CalcSize(this.height, Level)
            };
        }
 
        public void Dispose()
        {
            this.initialized?.Dispose();
            this.initialized = null;
        }
    }
}