C# bindings (#650)

* First workin version of the C# bindings

* Update README.md

Signed-off-by: mvenditto <venditto.matteo@gmail.com>

* Added more docs + fixed prompt callback signature

* build scripts revision

* Added .editorconfig + fixed style issues

---------

Signed-off-by: mvenditto <venditto.matteo@gmail.com>

gpt4all-bindings/csharp/Gpt4All/Prediction/ITextPrediction.cs

@@ -0,0 +1,31 @@
+namespace Gpt4All;
+
+/// <summary>
+/// Interface for text prediction services
+/// </summary>
+public interface ITextPrediction
+{
+    /// <summary>
+    /// Get prediction results for the prompt and provided options.
+    /// </summary>
+    /// <param name="text">The text to complete</param>
+    /// <param name="opts">The prediction settings</param>
+    /// <param name="cancellationToken">The <see cref="CancellationToken"/> for cancellation requests. The default is <see cref="CancellationToken.None"/>.</param>
+    /// <returns>The prediction result generated by the model</returns>
+    Task<ITextPredictionResult> GetPredictionAsync(
+        string text,
+        PredictRequestOptions opts,
+        CancellationToken cancellation = default);
+
+    /// <summary>
+    /// Get streaming prediction results for the prompt and provided options.
+    /// </summary>
+    /// <param name="text">The text to complete</param>
+    /// <param name="opts">The prediction settings</param>
+    /// <param name="cancellationToken">The <see cref="CancellationToken"/> for cancellation requests. The default is <see cref="CancellationToken.None"/>.</param>
+    /// <returns>The prediction result generated by the model</returns>
+    Task<ITextPredictionStreamingResult> GetStreamingPredictionAsync(
+        string text,
+        PredictRequestOptions opts,
+        CancellationToken cancellationToken = default);
+}

gpt4all-bindings/csharp/Gpt4All/Prediction/ITextPredictionResult.cs

@@ -0,0 +1,10 @@
+namespace Gpt4All;
+
+public interface ITextPredictionResult
+{
+    bool Success { get; }
+
+    string? ErrorMessage { get; }
+
+    Task<string> GetPredictionAsync(CancellationToken cancellationToken = default);
+}

gpt4all-bindings/csharp/Gpt4All/Prediction/ITextPredictionStreamingResult.cs

@@ -0,0 +1,6 @@
+namespace Gpt4All;
+
+public interface ITextPredictionStreamingResult : ITextPredictionResult
+{
+    IAsyncEnumerable<string> GetPredictionStreamingAsync(CancellationToken cancellationToken = default);
+}

gpt4all-bindings/csharp/Gpt4All/Prediction/PredictRequestOptions.cs

@@ -0,0 +1,30 @@
+namespace Gpt4All;
+
+public record PredictRequestOptions
+{
+    public nuint LogitsSize { get; init; } = 0;
+
+    public nuint TokensSize { get; init; } = 0;
+
+    public int PastConversationTokensNum { get; init; } = 0;
+
+    public int ContextSize { get; init; } = 1024;
+
+    public int TokensToPredict { get; init; } = 128;
+
+    public int TopK { get; init; } = 40;
+
+    public float TopP { get; init; } = 0.9f;
+
+    public float Temperature { get; init; } = 0.1f;
+
+    public int Batches { get; init; } = 8;
+
+    public float RepeatPenalty { get; init; } = 1.2f;
+
+    public int RepeatLastN { get; init; } = 10;
+
+    public float ContextErase { get; init; } = 0.5f;
+
+    public static readonly PredictRequestOptions Defaults = new();
+}

gpt4all-bindings/csharp/Gpt4All/Prediction/TextPredictionResult.cs

@@ -0,0 +1,27 @@
+using System.Text;
+
+namespace Gpt4All;
+
+public record TextPredictionResult : ITextPredictionResult
+{
+    private readonly StringBuilder _result;
+
+    public bool Success { get; internal set; } = true;
+
+    public string? ErrorMessage { get; internal set; }
+
+    internal TextPredictionResult()
+    {
+        _result = new StringBuilder();
+    }
+
+    internal void Append(string token)
+    {
+        _result.Append(token);
+    }
+
+    public Task<string> GetPredictionAsync(CancellationToken cancellationToken = default)
+    {
+        return Task.FromResult(_result.ToString());
+    }
+}

gpt4all-bindings/csharp/Gpt4All/Prediction/TextPredictionStreamingResult.cs

@@ -0,0 +1,49 @@
+using System.Text;
+using System.Threading.Channels;
+
+namespace Gpt4All;
+
+public record TextPredictionStreamingResult : ITextPredictionStreamingResult
+{
+    private readonly Channel<string> _channel;
+
+    public bool Success { get; internal set; } = true;
+
+    public string? ErrorMessage { get; internal set; }
+
+    public Task Completion => _channel.Reader.Completion;
+
+    internal TextPredictionStreamingResult()
+    {
+        _channel = Channel.CreateUnbounded<string>();
+    }
+
+    internal bool Append(string token)
+    {
+        return _channel.Writer.TryWrite(token);
+    }
+
+    internal void Complete()
+    {
+        _channel.Writer.Complete();
+    }
+
+    public async Task<string> GetPredictionAsync(CancellationToken cancellationToken = default)
+    {
+        var sb = new StringBuilder();
+
+        var tokens = GetPredictionStreamingAsync(cancellationToken).ConfigureAwait(false);
+
+        await foreach (var token in tokens)
+        {
+            sb.Append(token);
+        }
+
+        return sb.ToString();
+    }
+
+    public IAsyncEnumerable<string> GetPredictionStreamingAsync(CancellationToken cancellationToken = default)
+    {
+        return _channel.Reader.ReadAllAsync(cancellationToken);
+    }
+}