module file_lists

import os

// expand_files accepts a list of files and folders, and returns a list of all the .v and .vsh files, found in them.
// The input list of files, supports recursive `@file.lst` expansion, where each line is treated as another file/folder.
pub fn expand_files(files []string) ![]string {
    mut res := []string{}
    for file in files {
        if file == '' {
            continue
        }
        if file.starts_with('@') {
            lst_path := files[0].all_after('@').trim_space()
            listed_files := os.read_file(lst_path)!.split('\n').map(it.trim_space())
            res << expand_files(listed_files)!
            continue
        }
        if os.is_dir(file) {
            res << os.walk_ext(file, '.vsh')
            res << os.walk_ext(file, '.v')
            continue
        }
        if os.exists(file) {
            res << file
        }
    }
    return res
}