import system, subprocess, os, tamarin, json, re

def run(args, as_root = False, capture_output=False):
    """Run rkt with the specified args (use the local copy if rkt is not found in the $PATH)"""
    rkt_bin = system.which('rkt', tamarin.get_workspace_subdir('rkt'))
    cmd = ( ["sudo", "-E", rkt_bin] if os.geteuid() != 0 and as_root == True else [rkt_bin] ) + args
    print(" ".join(cmd))
    if capture_output:
        return subprocess.check_output(cmd, stdin=subprocess.PIPE)
    else:
        return subprocess.call(cmd, stdin=subprocess.PIPE)

def get_images_list(rkt_flags = []):
    output = run([
        "image",
        "list",
        "--format=json"
    ] + rkt_flags, capture_output=True)
    # Fetch the list of installed images
    return json.loads(output.decode('utf-8'))

def find_image_by_name(name_pattern, rkt_flags = []):
    if type(name_pattern) is str:
        name_pattern = re.compile(name_pattern)
    images_list = get_images_list(rkt_flags = rkt_flags)
    for image in images_list:
        if name_pattern.search(image['name']):
            return image
    return None

def export_image(image_id, dest_file, rkt_flags = []):
    run([
        "image",
        "export",
        image_id,
        dest_file,
    ] + rkt_flags)