ContentGen_BE/media-worker/Services/VoiceboxTtsService.cs

using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using SaasMediaWorker.Configuration;
using SaasMediaWorker.Models;

namespace SaasMediaWorker.Services;

/// <summary>
/// VoiceBox AI Studio Client — Metin → Ses dönüşümü (%100 Yerel ve Ücretsiz).
/// </summary>
public class VoiceboxTtsService
{
    private readonly HttpClient _httpClient;
    private readonly ILogger<VoiceboxTtsService> _logger;
    private readonly ApiSettings _settings;

    public VoiceboxTtsService(
        HttpClient httpClient,
        ILogger<VoiceboxTtsService> logger,
        IOptions<ApiSettings> settings)
    {
        _httpClient = httpClient;
        _logger = logger;
        _settings = settings.Value;

        // Docker ağı üzerinde voicebox servisine bağlanır
        // C# projesinin appsettings.json dosyasından da okunabilir ama varsayılanı atıyoruz
        _httpClient.BaseAddress = new Uri("http://contgen-ai-voicebox:17493/");
        _httpClient.Timeout = TimeSpan.FromMinutes(5); // Yerel render işlemci hızına bağlı sürebilir
    }

    /// <summary>
    /// Bir sahnenin narration metnini sese çevirir ve dosyaya kaydeder.
    /// </summary>
    public async Task<GeneratedMediaFile> GenerateNarrationAsync(
        ScenePayload scene,
        string outputDirectory,
        string voiceStyle,
        CancellationToken ct)
    {
        _logger.LogInformation(
            "🎙️ VoiceBox TTS üretimi — Sahne {Order}: \"{Text}\"",
            scene.Order,
            scene.NarrationText[..Math.Min(60, scene.NarrationText.Length)]);

        // VoiceBox'ta varsayılan bir profil (Örn: Kokoro default)
        var profileId = string.IsNullOrWhiteSpace(voiceStyle) ? "b6a8a474-0fc0-4a8f-b9f1-a1e4c84a8649" : voiceStyle;

        var requestBody = new
        {
            text = scene.NarrationText,
            profile_id = profileId,
            language = "tr",
            engine = "kokoro"
        };

        var content = new StringContent(
            JsonSerializer.Serialize(requestBody),
            Encoding.UTF8,
            "application/json");

        // 1. Asenkron üretim başlat
        var generateResponse = await _httpClient.PostAsync("generate", content, ct);
        generateResponse.EnsureSuccessStatusCode();

        var genJsonStr = await generateResponse.Content.ReadAsStringAsync(ct);
        using var genDoc = JsonDocument.Parse(genJsonStr);
        var generationId = genDoc.RootElement.GetProperty("id").GetString();
        
        if (string.IsNullOrEmpty(generationId))
        {
            throw new Exception("VoiceBox üretim başlatıldı ancak ID alınamadı.");
        }

        // 2. Durumu polling ile kontrol et
        string status = "generating";
        int attempts = 0;
        int maxAttempts = 120; // 120 * 2sn = 4 dakika

        while (status != "completed" && status != "failed" && attempts < maxAttempts && !ct.IsCancellationRequested)
        {
            await Task.Delay(2000, ct);
            
            var historyResponse = await _httpClient.GetAsync("history", ct);
            if (historyResponse.IsSuccessStatusCode)
            {
                var historyStr = await historyResponse.Content.ReadAsStringAsync(ct);
                using var historyDoc = JsonDocument.Parse(historyStr);
                
                JsonElement itemsElement;
                if (historyDoc.RootElement.ValueKind == JsonValueKind.Array)
                {
                    itemsElement = historyDoc.RootElement;
                }
                else if (historyDoc.RootElement.TryGetProperty("items", out var itemsProp) && itemsProp.ValueKind == JsonValueKind.Array)
                {
                    itemsElement = itemsProp;
                }
                else
                {
                    continue; // Geçersiz format
                }

                foreach (var item in itemsElement.EnumerateArray())
                {
                    if (item.GetProperty("id").GetString() == generationId)
                    {
                        if (item.TryGetProperty("status", out var statusProp))
                        {
                            status = statusProp.GetString() ?? "completed";
                        }
                        else
                        {
                            status = "completed";
                        }
                        
                        if (status == "failed")
                        {
                            var errorMsg = item.TryGetProperty("error", out var errProp) ? errProp.GetString() : "Bilinmeyen üretim hatası";
                            throw new Exception($"VoiceBox ses üretemedi: {errorMsg}");
                        }
                        break;
                    }
                }
            }
            attempts++;
        }

        if (status != "completed")
        {
            throw new Exception("VoiceBox ses üretimi zaman aşımına uğradı.");
        }

        // 3. Üretilen ses dosyasını indir
        var audioResponse = await _httpClient.GetAsync($"audio/{generationId}", ct);
        audioResponse.EnsureSuccessStatusCode();

        var audioBytes = await audioResponse.Content.ReadAsByteArrayAsync(ct);
        
        var extension = audioResponse.Content.Headers.ContentType?.MediaType == "audio/mpeg" ? "mp3" : "wav";
        var outputPath = Path.Combine(outputDirectory, $"scene_{scene.Order:D2}_narration.{extension}");
        
        await File.WriteAllBytesAsync(outputPath, audioBytes, ct);

        var fileInfo = new FileInfo(outputPath);

        _logger.LogInformation(
            "VoiceBox TTS tamamlandı — Sahne {Order}: {Size} bytes",
            scene.Order, fileInfo.Length);

        return new GeneratedMediaFile
        {
            SceneId = scene.Id,
            SceneOrder = scene.Order,
            Type = MediaFileType.AudioNarration,
            LocalPath = outputPath,
            FileSizeBytes = fileInfo.Length,
            DurationSeconds = scene.Duration,
            MimeType = $"audio/{extension}",
            AiProvider = "voicebox"
        };
    }
}