namespace GermanApp.Infrastructure.Configuration;

/// <summary>
/// Configuration settings for Vosk speech recognition service.
/// This is part of the Infrastructure layer.
/// 
/// Setup Instructions:
/// 1. Install Python 3.8+: https://www.python.org/downloads/
/// 2. Install Vosk: pip install vosk
/// 3. Download German model: 
///    wget https://alphacephei.com/vosk/models/vosk-model-de-0.22.zip
///    unzip vosk-model-de-0.22.zip
/// 4. Set ModelPath to the extracted directory (e.g., /models/vosk-model-de-0.22)
/// 
/// Note: Model requires ~500MB disk space
/// </summary>
public class VoskConfig
{
    /// <summary>
    /// Path to the Python executable.
    /// Default: python3
    /// </summary>
    public string PythonPath { get; set; } = "python3";

    /// <summary>
    /// Path to the Vosk model directory.
    /// Example: /models/vosk-model-de-0.22
    /// </summary>
    public string ModelPath { get; set; } = string.Empty;

    /// <summary>
    /// Expected audio sample rate in Hz.
    /// Vosk models typically use 16000 Hz.
    /// Default: 16000
    /// </summary>
    public int SampleRate { get; set; } = 16000;

    /// <summary>
    /// Maximum audio duration in seconds for speech recognition.
    /// Default: 60 seconds
    /// </summary>
    public int MaxAudioDurationSeconds { get; set; } = 60;

    /// <summary>
    /// Timeout in seconds for Vosk processing.
    /// Default: 30 seconds
    /// </summary>
    public int TimeoutSeconds { get; set; } = 30;

    /// <summary>
    /// Whether to enable beam width adjustment for accuracy vs speed tradeoff.
    /// Higher values = more accurate but slower.
    /// Default: 16
    /// </summary>
    public int BeamWidth { get; set; } = 16;

    /// <summary>
    /// Path to the Vosk Python package/module.
    /// Default: vosk
    /// </summary>
    public string ModulePath { get; set; } = "vosk";

    /// <summary>
    /// Validates the configuration.
    /// </summary>
    /// <exception cref="ArgumentException">Thrown when configuration is invalid</exception>
    public void Validate()
    {
        if (string.IsNullOrWhiteSpace(PythonPath))
        {
            throw new ArgumentException("Vosk PythonPath is required");
        }

        if (string.IsNullOrWhiteSpace(ModelPath))
        {
            throw new ArgumentException("Vosk ModelPath is required");
        }

        if (SampleRate <= 0)
        {
            throw new ArgumentException("SampleRate must be greater than 0");
        }

        if (MaxAudioDurationSeconds <= 0)
        {
            throw new ArgumentException("MaxAudioDurationSeconds must be greater than 0");
        }

        if (TimeoutSeconds <= 0)
        {
            throw new ArgumentException("TimeoutSeconds must be greater than 0");
        }

        if (BeamWidth <= 0)
        {
            throw new ArgumentException("BeamWidth must be greater than 0");
        }

        if (string.IsNullOrWhiteSpace(ModulePath))
        {
            throw new ArgumentException("Vosk ModulePath is required");
        }
    }
}