Added audio recording (#615)

app/MindWork AI Studio/Components/VoiceRecorder.razor

@@ -0,0 +1,16 @@
+@using AIStudio.Settings.DataModel
+
+@namespace AIStudio.Components
+@inherits MSGComponentBase
+
+@if (PreviewFeatures.PRE_SPEECH_TO_TEXT_2026.IsEnabled(this.SettingsManager))
+{
+    <MudTooltip Text="@this.Tooltip">
+        <MudToggleIconButton Toggled="@this.isRecording"
+                             ToggledChanged="@this.OnRecordingToggled"
+                             Icon="@Icons.Material.Filled.Mic"
+                             ToggledIcon="@Icons.Material.Filled.Stop"
+                             Color="Color.Primary"
+                             ToggledColor="Color.Error"/>
+    </MudTooltip>
+}

app/MindWork AI Studio/Components/VoiceRecorder.razor.cs

@@ -0,0 +1,197 @@
+using AIStudio.Tools.MIME;
+using AIStudio.Tools.Services;
+
+using Microsoft.AspNetCore.Components;
+
+namespace AIStudio.Components;
+
+public partial class VoiceRecorder : MSGComponentBase
+{
+    [Inject]
+    private ILogger<VoiceRecorder> Logger { get; init; } = null!;
+    
+    [Inject]
+    private IJSRuntime JsRuntime { get; init; } = null!;
+    
+    [Inject]
+    private RustService RustService { get; init; } = null!;
+
+    private uint numReceivedChunks;
+    private bool isRecording;
+    private FileStream? currentRecordingStream;
+    private string? currentRecordingPath;
+    private string? currentRecordingMimeType;
+    private DotNetObjectReference<VoiceRecorder>? dotNetReference;
+    
+    private string Tooltip => this.isRecording ? T("Stop recording and start transcription") : T("Start recording your voice for a transcription");
+    
+    private async Task OnRecordingToggled(bool toggled)
+    {
+        if (toggled)
+        {
+            var mimeTypes = GetPreferredMimeTypes(
+                Builder.Create().UseAudio().UseSubtype(AudioSubtype.OGG).Build(),
+                Builder.Create().UseAudio().UseSubtype(AudioSubtype.AAC).Build(),
+                Builder.Create().UseAudio().UseSubtype(AudioSubtype.MP3).Build(),
+                Builder.Create().UseAudio().UseSubtype(AudioSubtype.AIFF).Build(),
+                Builder.Create().UseAudio().UseSubtype(AudioSubtype.WAV).Build(),
+                Builder.Create().UseAudio().UseSubtype(AudioSubtype.FLAC).Build()
+            );
+
+            this.Logger.LogInformation("Starting audio recording with preferred MIME types: '{PreferredMimeTypes}'.", string.Join<MIMEType>(", ", mimeTypes));
+
+            // Create a DotNetObjectReference to pass to JavaScript:
+            this.dotNetReference = DotNetObjectReference.Create(this);
+
+            // Initialize the file stream for writing chunks:
+            await this.InitializeRecordingStream();
+
+            var mimeTypeStrings = mimeTypes.ToStringArray();
+            var actualMimeType = await this.JsRuntime.InvokeAsync<string>("audioRecorder.start", this.dotNetReference, mimeTypeStrings);
+
+            // Store the MIME type for later use:
+            this.currentRecordingMimeType = actualMimeType;
+
+            this.Logger.LogInformation("Audio recording started with MIME type: '{ActualMimeType}'.", actualMimeType);
+            this.isRecording = true;
+        }
+        else
+        {
+            var result = await this.JsRuntime.InvokeAsync<AudioRecordingResult>("audioRecorder.stop");
+            if (result.ChangedMimeType)
+                this.Logger.LogWarning("The recorded audio MIME type was changed to '{ResultMimeType}'.", result.MimeType);
+
+            // Close and finalize the recording stream:
+            await this.FinalizeRecordingStream();
+
+            this.isRecording = false;
+            this.StateHasChanged();
+        }
+    }
+
+    private static MIMEType[] GetPreferredMimeTypes(params MIMEType[] mimeTypes)
+    {
+        // Default list if no parameters provided:
+        if (mimeTypes.Length is 0)
+        {
+            var audioBuilder = Builder.Create().UseAudio();
+            return
+            [
+                audioBuilder.UseSubtype(AudioSubtype.WEBM).Build(),
+                audioBuilder.UseSubtype(AudioSubtype.OGG).Build(),
+                audioBuilder.UseSubtype(AudioSubtype.MP4).Build(),
+                audioBuilder.UseSubtype(AudioSubtype.MPEG).Build(),
+            ];
+        }
+
+        return mimeTypes;
+    }
+
+    private async Task InitializeRecordingStream()
+    {
+        this.numReceivedChunks = 0;
+        var dataDirectory = await this.RustService.GetDataDirectory();
+        var recordingDirectory = Path.Combine(dataDirectory, "audioRecordings");
+        if (!Directory.Exists(recordingDirectory))
+            Directory.CreateDirectory(recordingDirectory);
+
+        var fileName = $"recording_{DateTime.UtcNow:yyyyMMdd_HHmmss}.audio";
+        this.currentRecordingPath = Path.Combine(recordingDirectory, fileName);
+        this.currentRecordingStream = new FileStream(this.currentRecordingPath, FileMode.Create, FileAccess.Write, FileShare.None, bufferSize: 8192, useAsync: true);
+
+        this.Logger.LogInformation("Initialized audio recording stream: '{RecordingPath}'.", this.currentRecordingPath);
+    }
+
+    [JSInvokable]
+    public async Task OnAudioChunkReceived(byte[] chunkBytes)
+    {
+        if (this.currentRecordingStream is null)
+        {
+            this.Logger.LogWarning("Received audio chunk but no recording stream is active.");
+            return;
+        }
+
+        try
+        {
+            this.numReceivedChunks++;
+            await this.currentRecordingStream.WriteAsync(chunkBytes);
+            await this.currentRecordingStream.FlushAsync();
+
+            this.Logger.LogDebug("Wrote {ByteCount} bytes to recording stream.", chunkBytes.Length);
+        }
+        catch (Exception ex)
+        {
+            this.Logger.LogError(ex, "Error writing audio chunk to stream.");
+        }
+    }
+
+    private async Task FinalizeRecordingStream()
+    {
+        if (this.currentRecordingStream is not null)
+        {
+            await this.currentRecordingStream.FlushAsync();
+            await this.currentRecordingStream.DisposeAsync();
+            this.currentRecordingStream = null;
+
+            // Rename the file with the correct extension based on MIME type:
+            if (this.currentRecordingPath is not null && this.currentRecordingMimeType is not null)
+            {
+                var extension = GetFileExtension(this.currentRecordingMimeType);
+                var newPath = Path.ChangeExtension(this.currentRecordingPath, extension);
+
+                if (File.Exists(this.currentRecordingPath))
+                {
+                    File.Move(this.currentRecordingPath, newPath, overwrite: true);
+                    this.Logger.LogInformation("Finalized audio recording over {NumChunks} streamed audio chunks to the file '{RecordingPath}'.", this.numReceivedChunks, newPath);
+                }
+            }
+        }
+
+        this.currentRecordingPath = null;
+        this.currentRecordingMimeType = null;
+
+        // Dispose the .NET reference:
+        this.dotNetReference?.Dispose();
+        this.dotNetReference = null;
+    }
+
+    private static string GetFileExtension(string mimeType)
+    {
+        var baseMimeType = mimeType.Split(';')[0].Trim().ToLowerInvariant();
+        return baseMimeType switch
+        {
+            "audio/webm" => ".webm",
+            "audio/ogg" => ".ogg",
+            "audio/mp4" => ".m4a",
+            "audio/mpeg" => ".mp3",
+            "audio/wav" => ".wav",
+            "audio/x-wav" => ".wav",
+            _ => ".audio" // Fallback
+        };
+    }
+
+    private sealed class AudioRecordingResult
+    {
+        public string MimeType { get; init; } = string.Empty;
+
+        public bool ChangedMimeType { get; init; }
+    }
+
+    #region Overrides of MSGComponentBase
+
+    protected override void DisposeResources()
+    {
+        // Clean up recording resources if still active:
+        if (this.currentRecordingStream is not null)
+        {
+            this.currentRecordingStream.Dispose();
+            this.currentRecordingStream = null;
+        }
+
+        this.dotNetReference?.Dispose();
+        this.dotNetReference = null;
+        base.DisposeResources();
+    }
+
+    #endregion
+}