use std::path::PathBuf;

use tauri::Manager;

use kon_core::types::AudioSamples;

/// Save PCM f32 samples as a WAV file. Returns the file path.
#[tauri::command]
pub async fn save_audio(
    app: tauri::AppHandle,
    samples: Vec<f32>,
    output_folder: Option<String>,
) -> Result<String, String> {
    let recordings_dir = if let Some(ref folder) = output_folder {
        if !folder.is_empty() {
            PathBuf::from(folder)
        } else {
            app.path()
                .app_local_data_dir()
                .map_err(|e: tauri::Error| e.to_string())?
                .join("recordings")
        }
    } else {
        app.path()
            .app_local_data_dir()
            .map_err(|e: tauri::Error| e.to_string())?
            .join("recordings")
    };

    std::fs::create_dir_all(&recordings_dir)
        .map_err(|e| format!("Failed to create recordings dir: {e}"))?;

    let timestamp = std::time::SystemTime::now()
        .duration_since(std::time::UNIX_EPOCH)
        .unwrap_or_default()
        .as_secs();
    let filename = format!("kon-{timestamp}.wav");
    let path = recordings_dir.join(&filename);
    let path_clone = path.clone();

    tokio::task::spawn_blocking(move || {
        let audio = AudioSamples::mono_16khz(samples);
        kon_audio::write_wav(&path_clone, &audio).map_err(|e| e.to_string())
    })
    .await
    .map_err(|e| e.to_string())??;

    Ok(path.to_string_lossy().to_string())
}