import sys
import subprocess as sp

from os.path import isdir
from ucloud.config import env_vars


def check():
    #########################
    #  ucloud-image-scanner #
    #########################
    if env_vars.get('STORAGE_BACKEND') == 'filesystem' and not isdir(env_vars.get('IMAGE_DIR')):
        print("You have set STORAGE_BACKEND to filesystem. So,"
              "the {} must exists. But, it don't".format(env_vars.get('IMAGE_DIR')))
        sys.exit(1)

    try:
        sp.check_output(['which', 'qemu-img'])
    except Exception:
        print("qemu-img missing")
        sys.exit(1)

    ###############
    # ucloud-host #
    ###############

    if env_vars.get('STORAGE_BACKEND') == 'filesystem' and not isdir(env_vars.get('VM_DIR')):
        print("You have set STORAGE_BACKEND to filesystem. So, the vm directory mentioned"
              " in .env file must exists. But, it don't.")
        sys.exit(1)

if __name__ == "__main__":
    check()