Fixed some crashes in response strings source generator, reorganized more submodules into their folders

src/NadekoBot/Modules/Music/_Common/Resolvers/LocalTrackResolver.cs

@@ -0,0 +1,120 @@
+using System.ComponentModel;
+using System.Diagnostics;
+using System.Text;
+
+namespace NadekoBot.Modules.Music.Resolvers;
+
+public sealed class LocalTrackResolver : ILocalTrackResolver
+{
+    private static readonly HashSet<string> _musicExtensions = new[]
+    {
+        ".MP4", ".MP3", ".FLAC", ".OGG", ".WAV", ".WMA", ".WMV", ".AAC", ".MKV", ".WEBM", ".M4A", ".AA", ".AAX",
+        ".ALAC", ".AIFF", ".MOV", ".FLV", ".OGG", ".M4V"
+    }.ToHashSet();
+
+    public async Task<ITrackInfo?> ResolveByQueryAsync(string query)
+    {
+        if (!File.Exists(query))
+            return null;
+
+        var trackDuration = await Ffprobe.GetTrackDurationAsync(query);
+        return new SimpleTrackInfo(Path.GetFileNameWithoutExtension(query),
+            $"https://google.com?q={Uri.EscapeDataString(Path.GetFileNameWithoutExtension(query))}",
+            "https://cdn.discordapp.com/attachments/155726317222887425/261850914783100928/1482522077_music.png",
+            trackDuration,
+            MusicPlatform.Local,
+            $"\"{Path.GetFullPath(query)}\"");
+    }
+
+    public async IAsyncEnumerable<ITrackInfo> ResolveDirectoryAsync(string dirPath)
+    {
+        DirectoryInfo dir;
+        try
+        {
+            dir = new(dirPath);
+        }
+        catch (Exception ex)
+        {
+            Log.Error(ex, "Specified directory {DirectoryPath} could not be opened", dirPath);
+            yield break;
+        }
+
+        var files = dir.EnumerateFiles()
+                       .Where(x =>
+                       {
+                           if (!x.Attributes.HasFlag(FileAttributes.Hidden | FileAttributes.System)
+                               && _musicExtensions.Contains(x.Extension.ToUpperInvariant())) return true;
+                           return false;
+                       });
+
+        var firstFile = files.FirstOrDefault()?.FullName;
+        if (firstFile is null)
+            yield break;
+
+        var firstData = await ResolveByQueryAsync(firstFile);
+        if (firstData is not null)
+            yield return firstData;
+
+        var fileChunks = files.Skip(1).Chunk(10);
+        foreach (var chunk in fileChunks)
+        {
+            var part = await chunk.Select(x => ResolveByQueryAsync(x.FullName)).WhenAll();
+
+            // nullable reference types being annoying
+            foreach (var p in part)
+            {
+                if (p is null)
+                    continue;
+
+                yield return p;
+            }
+        }
+    }
+}
+
+public static class Ffprobe
+{
+    public static async Task<TimeSpan> GetTrackDurationAsync(string query)
+    {
+        query = query.Replace("\"", "");
+
+        try
+        {
+            using var p = Process.Start(new ProcessStartInfo
+            {
+                FileName = "ffprobe",
+                Arguments =
+                    $"-v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 -- \"{query}\"",
+                UseShellExecute = false,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                StandardOutputEncoding = Encoding.UTF8,
+                StandardErrorEncoding = Encoding.UTF8,
+                CreateNoWindow = true
+            });
+
+            if (p is null)
+                return TimeSpan.Zero;
+
+            var data = await p.StandardOutput.ReadToEndAsync();
+            if (double.TryParse(data, out var seconds))
+                return TimeSpan.FromSeconds(seconds);
+
+            var errorData = await p.StandardError.ReadToEndAsync();
+            if (!string.IsNullOrWhiteSpace(errorData))
+                Log.Warning("Ffprobe warning for file {FileName}: {ErrorMessage}", query, errorData);
+
+            return TimeSpan.Zero;
+        }
+        catch (Win32Exception)
+        {
+            Log.Warning("Ffprobe was likely not installed. Local song durations will show as (?)");
+        }
+        catch (Exception ex)
+        {
+            Log.Error(ex, "Unknown exception running ffprobe; {ErrorMessage}", ex.Message);
+        }
+
+        return TimeSpan.Zero;
+    }
+}