use std::fs;
use tauri::command;

const IMAGE_EXTS: [&str; 6] = ["jpg", "jpeg", "png", "gif", "bmp", "webp"];

#[command]
fn read_directory_images(dir_path: &str) -> Result<Vec<String>, String> {
    let entries = fs::read_dir(dir_path).map_err(|e| e.to_string())?;
    
    let mut images: Vec<String> = entries
        .filter_map(|e| e.ok())
        .map(|e| e.path())
        .filter(|p| p.is_file() && is_image(p.extension()))
        .filter_map(|p| p.to_str().map(String::from))
        .collect();
    
    images.sort();
    Ok(images)
}

fn is_image(ext: Option<&std::ffi::OsStr>) -> bool {
    ext.map(|e| IMAGE_EXTS.contains(&e.to_string_lossy().to_lowercase().as_str())).unwrap_or(false)
}

#[cfg_attr(mobile, tauri::mobile_entry_point)]
pub fn run() {
    tauri::Builder::default()
        .plugin(tauri_plugin_opener::init())
        .plugin(tauri_plugin_dialog::init())
        .plugin(tauri_plugin_fs::init())
        .invoke_handler(tauri::generate_handler![read_directory_images])
        .run(tauri::generate_context!())
        .expect("error while running tauri application");
}