Implement meeting assistant v1

2026-05-20 02:06:16 +02:00
parent 90df1edc03
commit 0297bcc0f6
120 changed files with 11883 additions and 180 deletions
@@ -0,0 +1,182 @@
+using System.Text.Json;
+
+namespace MeetingAssistant.Transcription;
+
+public sealed class FunAsrMessageParser
+{
+    private readonly FunAsrOptions options;
+
+    public FunAsrMessageParser(FunAsrOptions options)
+    {
+        this.options = options;
+    }
+
+    public FunAsrParsedMessage Parse(string message)
+    {
+        using var document = JsonDocument.Parse(message);
+        var root = document.RootElement;
+        var mode = GetString(root, "mode");
+        var isFinal = GetBoolean(root, "is_final");
+        var shouldEmit = options.EmitOnlinePartials || !IsOnlineMode(mode);
+        var segments = shouldEmit ? ReadSegments(root) : [];
+
+        return new FunAsrParsedMessage(IsTerminal: isFinal && !IsOnlineMode(mode), segments);
+    }
+
+    private static List<TranscriptionSegment> ReadSegments(JsonElement root)
+    {
+        var sentenceSegments = ReadSentenceSegments(root, "sentence_info");
+        if (sentenceSegments.Count > 0)
+        {
+            return sentenceSegments;
+        }
+
+        var stampSegments = ReadSentenceSegments(root, "stamp_sents");
+        if (stampSegments.Count > 0)
+        {
+            return stampSegments;
+        }
+
+        var text = GetString(root, "text").Trim();
+        if (string.IsNullOrWhiteSpace(text))
+        {
+            return [];
+        }
+
+        var (start, end) = ReadTimestampRange(root);
+        return [new TranscriptionSegment(start, end, ReadSpeaker(root), text)];
+    }
+
+    private static List<TranscriptionSegment> ReadSentenceSegments(JsonElement root, string propertyName)
+    {
+        if (!root.TryGetProperty(propertyName, out var sentences) || sentences.ValueKind != JsonValueKind.Array)
+        {
+            return [];
+        }
+
+        var segments = new List<TranscriptionSegment>();
+        foreach (var sentence in sentences.EnumerateArray())
+        {
+            var text = (GetString(sentence, "text") + GetString(sentence, "text_seg") + GetString(sentence, "punc")).Trim();
+            if (string.IsNullOrWhiteSpace(text))
+            {
+                continue;
+            }
+
+            segments.Add(new TranscriptionSegment(
+                TimeSpan.FromMilliseconds(GetDouble(sentence, "start")),
+                TimeSpan.FromMilliseconds(GetDouble(sentence, "end")),
+                ReadSpeaker(sentence),
+                text));
+        }
+
+        return segments;
+    }
+
+    private static (TimeSpan Start, TimeSpan End) ReadTimestampRange(JsonElement root)
+    {
+        if (!root.TryGetProperty("timestamp", out var timestamp))
+        {
+            return (TimeSpan.Zero, TimeSpan.Zero);
+        }
+
+        if (timestamp.ValueKind == JsonValueKind.String)
+        {
+            var value = timestamp.GetString();
+            if (string.IsNullOrWhiteSpace(value))
+            {
+                return (TimeSpan.Zero, TimeSpan.Zero);
+            }
+
+            using var document = JsonDocument.Parse(value);
+            return ReadTimestampArray(document.RootElement);
+        }
+
+        return ReadTimestampArray(timestamp);
+    }
+
+    private static (TimeSpan Start, TimeSpan End) ReadTimestampArray(JsonElement timestamp)
+    {
+        if (timestamp.ValueKind != JsonValueKind.Array)
+        {
+            return (TimeSpan.Zero, TimeSpan.Zero);
+        }
+
+        double? start = null;
+        double? end = null;
+        foreach (var item in timestamp.EnumerateArray())
+        {
+            if (item.ValueKind != JsonValueKind.Array)
+            {
+                continue;
+            }
+
+            var values = item.EnumerateArray().ToArray();
+            if (values.Length < 2)
+            {
+                continue;
+            }
+
+            start ??= ReadNumber(values[0]);
+            end = ReadNumber(values[1]);
+        }
+
+        return (
+            TimeSpan.FromMilliseconds(start ?? 0),
+            TimeSpan.FromMilliseconds(end ?? start ?? 0));
+    }
+
+    private static string ReadSpeaker(JsonElement element)
+    {
+        var speaker = GetString(element, "spk_name");
+        if (!string.IsNullOrWhiteSpace(speaker))
+        {
+            return speaker;
+        }
+
+        speaker = GetString(element, "speaker");
+        if (!string.IsNullOrWhiteSpace(speaker))
+        {
+            return speaker;
+        }
+
+        if (element.TryGetProperty("spk", out var spk))
+        {
+            return $"Speaker {spk}";
+        }
+
+        return "Unknown";
+    }
+
+    private static bool IsOnlineMode(string mode)
+    {
+        return mode.Equals("online", StringComparison.OrdinalIgnoreCase)
+            || mode.Equals("2pass-online", StringComparison.OrdinalIgnoreCase);
+    }
+
+    private static string GetString(JsonElement element, string propertyName)
+    {
+        return element.TryGetProperty(propertyName, out var property) && property.ValueKind == JsonValueKind.String
+            ? property.GetString() ?? ""
+            : "";
+    }
+
+    private static bool GetBoolean(JsonElement element, string propertyName)
+    {
+        return element.TryGetProperty(propertyName, out var property)
+            && property.ValueKind is JsonValueKind.True or JsonValueKind.False
+            && property.GetBoolean();
+    }
+
+    private static double GetDouble(JsonElement element, string propertyName)
+    {
+        return element.TryGetProperty(propertyName, out var property) ? ReadNumber(property) : 0;
+    }
+
+    private static double ReadNumber(JsonElement element)
+    {
+        return element.ValueKind == JsonValueKind.Number && element.TryGetDouble(out var value) ? value : 0;
+    }
+}
+
+public sealed record FunAsrParsedMessage(bool IsTerminal, IReadOnlyList<TranscriptionSegment> Segments);