#!/usr/bin/python
from subprocess import CalledProcessError
import sys

sys.path.append('hooks')

from charmhelpers.contrib.storage.linux.ceph import Pool, pool_exists
from charmhelpers.core.hookenv import action_get, log, action_fail

__author__ = 'chris'


def delete_cache_tier():
    backer_pool = action_get("backer-pool")
    cache_pool = action_get("cache-pool")

    # Pre flight checks
    if not pool_exists('admin', backer_pool):
        log("Backer pool {} must exist before calling this".format(
            backer_pool))
        action_fail("remove-cache-tier failed. Backer pool {} must exist "
                    "before calling this".format(backer_pool))

    if not pool_exists('admin', cache_pool):
        log("Cache pool {} must exist before calling this".format(
            cache_pool))
        action_fail("remove-cache-tier failed. Cache pool {} must exist "
                    "before calling this".format(cache_pool))

    pool = Pool(service='admin', name=backer_pool)
    try:
        pool.remove_cache_tier(cache_pool=cache_pool)
    except CalledProcessError as err:
        log("Removing the cache tier failed with message: {}".format(
            err.message))
        action_fail("remove-cache-tier failed. Removing the cache tier failed "
                    "with message: {}".format(err.message))


if __name__ == '__main__':
    delete_cache_tier()