implemented logger and M3U8 parser

.gitignore

@@ -2,4 +2,5 @@ bin/
 obj/
 /packages/
 riderModule.iml
-/_ReSharper.Caches/
+/_ReSharper.Caches/
+.idea/

.idea/.idea.VkAudioDownloader/.idea/.gitignore

@@ -1,13 +0,0 @@
-# Default ignored files
-/shelf/
-/workspace.xml
-# Rider ignored files
-/contentModel.xml
-/.idea.VkAudioDownloader.iml
-/modules.xml
-/projectSettingsUpdater.xml
-# Editor-based HTTP Client requests
-/httpRequests/
-# Datasource local storage ignored files
-/dataSources/
-/dataSources.local.xml

.idea/.idea.VkAudioDownloader/.idea/encodings.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Encoding">
-    <file url="PROJECT" charset="UTF-8" />
-  </component>
-</project>

.idea/.idea.VkAudioDownloader/.idea/indexLayout.xml

@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="UserContentModel">
-    <attachedFolders />
-    <explicitIncludes />
-    <explicitExcludes />
-  </component>
-</project>

.idea/.idea.VkAudioDownloader/.idea/misc.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="com.jetbrains.rider.android.RiderAndroidMiscFileCreationComponent">
-    <option name="ENSURE_MISC_FILE_EXISTS" value="true" />
-  </component>
-</project>

.idea/.idea.VkAudioDownloader/.idea/vcs.xml

@@ -1,9 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/DTLib" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/VkNet.AudioBypass" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/vknet" vcs="Git" />
-  </component>
-</project>

DTLib

@@ -1 +1 @@
-Subproject commit f6d045ae2d97691d67bfa82a26e9c100bb3215a1
+Subproject commit c7016371a53efa266453e0ab4aacaae4fe260e9f

VkAudioDownloader.CLI/Program.cs

@@ -1,11 +1,30 @@
-using DTLib.Dtsod;
+using System;
+using System.Linq;
+using System.Net.Http;
+using DTLib.Dtsod;
+using DTLib.Filesystem;
 using VkAudioDownloader;
+using DTLib.Logging.New;
+using VkAudioDownloader.VkM3U8;
 
-var client = new VkClient(VkClientConfig.FromDtsod(new DtsodV23(File.ReadAllText("config.dtsod"))));
+
+if(!File.Exists("config.dtsod"))
+    File.Copy("config.dtsod.default","config.dtsod");
+
+var logger = new CompositeLogger(new DefaultLogFormat(true), 
+    new ConsoleLogger(), 
+            new FileLogger("logs", "VkAudioDownloaer"));
+var client = new VkClient(
+    VkClientConfig.FromDtsod(new DtsodV23(File.ReadAllText("config.dtsod"))), 
+        logger);
+logger.Log("main", LogSeverity.Info, "initializing api...");
+logger.DebugLogEnabled = true;
 client.Connect();
-Console.WriteLine(client.Api.Token);
-var audios = client.FindAudio("моя оборона");
-foreach (var a in audios)
-{
-    Console.WriteLine(a.Title);
-}
+var audio = client.FindAudio("гражданская оборона", 1).First();
+Console.WriteLine($"{audio.Title} -- {audio.Artist} [{TimeSpan.FromSeconds(audio.Duration)}]");
+var Http = new HttpClient();
+var m3u8 = await Http.GetStringAsync(audio.Url);
+Console.WriteLine("downloaded m3u8 playlist:\n" + m3u8);
+var parser = new M3U8Parser();
+var HLSPlaylist = parser.Parse(audio.Url, m3u8);
+Console.WriteLine(HLSPlaylist);

VkAudioDownloader.CLI/VkAudioDownloader.CLI.csproj

@@ -4,7 +4,7 @@
         <OutputType>Exe</OutputType>
         <TargetFramework>net6.0</TargetFramework>
         <LangVersion>10</LangVersion>
-        <ImplicitUsings>enable</ImplicitUsings>
+        <ImplicitUsings>disable</ImplicitUsings>
         <Nullable>enable</Nullable>
     </PropertyGroup>
 

VkAudioDownloader.sln

@@ -14,6 +14,14 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "VkNet.Generators", "vknet\V
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "VkNet.AudioBypassService", "VkNet.AudioBypass\VkNet.AudioBypassService\VkNet.AudioBypassService.csproj", "{5650A6DD-602D-49FF-A0B0-DB59BD63EACE}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "sulution_items", "sulution_items", "{2CBCAE99-53A3-4ADE-A08B-5755EC471878}"
+	ProjectSection(SolutionItems) = preProject
+		.gitignore = .gitignore
+		.gitmodules = .gitmodules
+	EndProjectSection
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DTLib.Logging", "DTLib\DTLib.Logging\DTLib.Logging.csproj", "{A087B535-371A-4A7E-883E-B5B290567E9A}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -48,5 +56,9 @@ Global
 		{5650A6DD-602D-49FF-A0B0-DB59BD63EACE}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{5650A6DD-602D-49FF-A0B0-DB59BD63EACE}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{5650A6DD-602D-49FF-A0B0-DB59BD63EACE}.Release|Any CPU.Build.0 = Release|Any CPU
+		{A087B535-371A-4A7E-883E-B5B290567E9A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{A087B535-371A-4A7E-883E-B5B290567E9A}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{A087B535-371A-4A7E-883E-B5B290567E9A}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{A087B535-371A-4A7E-883E-B5B290567E9A}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal

VkAudioDownloader/VkAudioDownloader.csproj

@@ -3,12 +3,14 @@
     <PropertyGroup>
         <TargetFramework>net6.0</TargetFramework>
         <LangVersion>10</LangVersion>
-        <ImplicitUsings>enable</ImplicitUsings>
+        <ImplicitUsings>disable</ImplicitUsings>
         <Nullable>enable</Nullable>
+        <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     </PropertyGroup>
 
     <ItemGroup>
         <ProjectReference Include="..\DTLib\DTLib.Dtsod\DTLib.Dtsod.csproj" />
+        <ProjectReference Include="..\DTLib\DTLib.Logging\DTLib.Logging.csproj" />
         <ProjectReference Include="..\DTLib\DTLib\DTLib.csproj" />
         <ProjectReference Include="..\VkNet.AudioBypass\VkNet.AudioBypassService\VkNet.AudioBypassService.csproj" />
         <ProjectReference Include="..\vknet\VkNet.Generators\VkNet.Generators.csproj" />

VkAudioDownloader/VkClient.cs

@@ -1,6 +1,6 @@
-global using DTLib;
-global using DTLib.Extensions;
-using DTLib.Logging;
+using System;
+using System.IO;
+using System.Net.Http;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
 using VkNet;
@@ -9,8 +9,10 @@ using VkNet.Model;
 using VkNet.Model.RequestParams;
 using VkNet.Utils;
 using VkNet.Model.Attachments;
-using VkNet.AudioBypassService;
 using VkNet.AudioBypassService.Extensions;
+using DTLib.Logging.DependencyInjection;
+using DTLib.Logging.New;
+using ILogger = DTLib.Logging.New.ILogger;
 
 namespace VkAudioDownloader;
 
@@ -20,15 +22,16 @@ public class VkClient : IDisposable
 {
     public VkApi Api;
     public VkClientConfig Config;
-    
-    public VkClient(VkClientConfig conf)
+    private ILogger _logger;
+
+    public VkClient(VkClientConfig conf, ILogger logger)
     {
         Config = conf;
-        var services = new ServiceCollection();
-        //services.AddSingleton<LoggerService>();
-        services.AddAudioBypass();
+        _logger = logger;
+        var services = new ServiceCollection()
+            .Add(new LoggerService<VkApi>(logger))
+            .AddAudioBypass();
         Api = new VkApi(services);
-        
     }
 
     public void Connect()
@@ -40,12 +43,12 @@ public class VkClient : IDisposable
         };
         if (Config.Token is not null)
         {
-            Console.WriteLine("authorizing by token");
+            _logger.Log(nameof(VkClient),LogSeverity.Info,"authorizing by token");
             authParams.AccessToken = Config.Token;
         }
         else
         {
-            Console.WriteLine("authorizing by login and password");
+            _logger.Log(nameof(VkClient),LogSeverity.Info,"authorizing by login and password");
             authParams.Login = Config.Login;
             authParams.Password = Config.Password;
         }

VkAudioDownloader/VkM3U8/AudioDecryptor.cs

@@ -0,0 +1,35 @@
+using System;
+using System.IO;
+using System.Security.Cryptography;
+
+namespace VkAudioDownloader.VkM3U8;
+
+public class AudioDecryptor : IDisposable
+{
+    private Aes Aes;
+    private ICryptoTransform Decryptor;
+
+    AudioDecryptor()
+    {
+        Aes=Aes.Create();
+        Aes.KeySize = 128;
+        Aes.Mode = CipherMode.CBC;
+        Aes.IV = new byte[4] { 0, 0, 0, 0 };
+        Aes.Padding = PaddingMode.Zeros;
+        Decryptor = Aes.CreateDecryptor();
+    }
+
+    public Stream Decrypt(Stream fragment) 
+        => new CryptoStream(fragment, Decryptor, CryptoStreamMode.Read);
+    
+    private bool _disposed;
+    public void Dispose()
+    {
+        if(_disposed) return;
+        Aes.Dispose();
+        Decryptor.Dispose();
+        _disposed = true;
+    }
+
+    ~AudioDecryptor() => Dispose();
+}

VkAudioDownloader/VkM3U8/HLSFragment.cs

@@ -0,0 +1,9 @@
+namespace VkAudioDownloader.VkM3U8;
+
+public record struct HLSFragment
+{
+    public string Name;
+    // public int Duration;
+    public bool Encrypted;
+    public string? EncryptionKeyUrl;
+}

VkAudioDownloader/VkM3U8/HLSPlaylist.cs

@@ -0,0 +1,25 @@
+namespace VkAudioDownloader.VkM3U8;
+
+public class HLSPlaylist
+{
+
+    public HLSFragment[] Fragments { get; internal set; } 
+
+    /// content duration in seconds
+    public int Duration { get; internal set; }
+    
+    /// url before index.m3u8
+    public string BaseUrl { get; internal set; }
+    
+    internal HLSPlaylist(HLSFragment[] fragments, int duration, string baseUrl)
+    {
+        Fragments = fragments;
+        Duration = duration;
+        BaseUrl = baseUrl;
+    }
+
+    public override string ToString() =>
+        $"BaseUrl: {BaseUrl}\n" +
+        $"Duration: {Duration}\n" +
+        $"Fragments: HLSFragment[{Fragments.Length}]";
+}

VkAudioDownloader/VkM3U8/M3U8Parser.cs

@@ -0,0 +1,93 @@
+using System;
+using System.Collections.Generic;
+
+namespace VkAudioDownloader.VkM3U8;
+
+public class M3U8Parser
+{
+    private string _m3u8="";
+    private int _pos;
+    private List<HLSFragment> _fragments = new();
+    private int _playlistDuration = 0;
+    private HLSFragment _currentFragment = default;
+    
+    // parses m3u8 playlist and resets state
+    public HLSPlaylist Parse(Uri m3u8Url, string m3u8Content)
+    {
+        _m3u8 = m3u8Content;
+        var line = NextLine();
+        while (!line.IsEmpty)
+        {
+            if (line.Contains('#'))
+                ParseHashTag(line);
+            else
+            {
+                _currentFragment.Name = line.ToString();
+                _fragments.Add(_currentFragment);
+                _currentFragment = default;
+            }
+                
+            line = NextLine();
+        }
+
+        string urlStr = m3u8Url.ToString();
+        var rezult = new HLSPlaylist(
+            _fragments.ToArray(),
+            _playlistDuration,
+            urlStr.Remove(urlStr.LastIndexOf('/')+1));
+        Clear();
+        return rezult;
+    }
+    
+    ReadOnlySpan<char> NextLine()
+    {
+        int pos = _pos;
+        int index = _m3u8.IndexOf('\n', pos);
+        if (index == -1)
+            index = _m3u8.Length - _pos;
+        if (index == 0)
+            return ReadOnlySpan<char>.Empty;
+        _pos = index+1;
+        if (_m3u8[index - 1] == '\r')
+            index--; // skip /r
+        var line = _m3u8.AsSpan(pos, index - pos);
+        return line;
+    }
+
+    private void ParseHashTag(ReadOnlySpan<char> line)
+    {
+        if(line.StartsWith("EXT-X-TARGETDURATION:"))
+            _playlistDuration=Int32.Parse(line.After(':'));
+        else if (line.StartsWith("#EXT-X-KEY:METHOD="))
+        {
+            var method = line.After("#EXT-X-KEY:METHOD=");
+            
+            if (method.ToString() == "NONE")
+            {
+                _currentFragment.Encrypted = false;
+                return;
+            }
+
+            var alg = method.Before(',');
+            if (alg.ToString() != "AES-128")
+                throw new Exception($"unknown encryption algorythm: {method}");
+            
+            var keyUrl=method.After("URI=\"").Before('\"');
+            if (!keyUrl.StartsWith("http"))
+                throw new Exception($"key uri is not url: {keyUrl}");
+            
+            // AES-128 which AudioDecryptor can decrypt
+            _currentFragment.Encrypted = true;
+            _currentFragment.EncryptionKeyUrl = keyUrl.ToString();
+        }
+    }
+
+    private void Clear()
+    {
+        _m3u8 = "";
+        _pos=0;
+        _fragments.Clear();
+        _currentFragment = default;
+        _playlistDuration = 0;
+    }
+}

VkAudioDownloader/VkM3U8/SpanHelper.cs

@@ -0,0 +1,39 @@
+using System;
+
+namespace VkAudioDownloader.VkM3U8;
+
+internal static class SpanHelper
+{
+    public static ReadOnlySpan<char> After(this ReadOnlySpan<char> span, char c)
+    {
+        var index = span.IndexOf(c);
+        if (index == -1)
+            throw new Exception($"char <{c}> not found in span <{span}>");
+        return span.Slice(index+1);
+    }
+    
+    public static ReadOnlySpan<char> After(this ReadOnlySpan<char> span, ReadOnlySpan<char> s)
+    {
+        var index = span.IndexOf(s);
+        if (index == -1)
+            throw new Exception($"span <{s}> not found in span <{span}>");
+        return span.Slice(index+s.Length);
+    }
+    
+    
+    public static ReadOnlySpan<char> Before(this ReadOnlySpan<char> span, char c)
+    {
+        var index = span.IndexOf(c);
+        if (index == -1)
+            throw new Exception($"char <{c}> not found in span <{span}>");
+        return span.Slice(0,index);
+    }
+    
+    public static ReadOnlySpan<char> Before(this ReadOnlySpan<char> span, ReadOnlySpan<char> s)
+    {
+        var index = span.IndexOf(s);
+        if (index == -1)
+            throw new Exception($"span <{s}> not found in span <{span}>");
+        return span.Slice(0,index);
+    }
+}