#!/usr/bin/env python3
import argparse
import os
import sys

if False:
    from typing import Set, Text

ZULIP_PATH = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
sys.path.append(ZULIP_PATH)
from scripts.lib.zulip_tools import GENERIC_CACHE_SCRIPT_PARSER, \
    generate_sha1sum_emoji, get_caches_to_be_purged, get_environment, \
    get_recent_deployments, purge_unused_caches

ENV = get_environment()
EMOJI_CACHE_PATH = "/srv/zulip-emoji-cache"
if ENV == "travis":
    EMOJI_CACHE_PATH = os.path.join(os.environ["HOME"], "zulip-emoji-cache")

def parse_args():
    # type: () -> argparse.Namespace
    parser = argparse.ArgumentParser(description="This script cleans unused zulip emoji caches.",
                                     parents=[GENERIC_CACHE_SCRIPT_PARSER, ])
    args = parser.parse_args()
    return args

def get_caches_in_use(threshold_days):
    # type: (int) -> Set[Text]
    setups_to_check = set([ZULIP_PATH, ])
    caches_in_use = set()

    if ENV == "prod":
        setups_to_check |= get_recent_deployments(threshold_days)
    if ENV == "dev":
        CACHE_SYMLINK = os.path.join(ZULIP_PATH, "static", "generated", "emoji")
        CURRENT_CACHE = os.path.dirname(os.path.realpath(CACHE_SYMLINK))
        caches_in_use.add(CURRENT_CACHE)

    for setup_dir in setups_to_check:
        zulip_emoji_dir = os.path.join(setup_dir, "tools", "setup", "emoji")
        if not os.path.exists(zulip_emoji_dir):
            # Most probably this is a deployment directory extracted from a
            # tarball so no emoji cache is associated with this.
            continue
        sha1sum_emoji = generate_sha1sum_emoji(setup_dir)
        caches_in_use.add(os.path.join(EMOJI_CACHE_PATH, sha1sum_emoji))
    return caches_in_use

def main():
    # type: () -> None
    args = parse_args()
    caches_in_use = get_caches_in_use(args.threshold_days)
    purge_unused_caches(EMOJI_CACHE_PATH, caches_in_use, args.threshold_days, args.dry_run, "emoji")

if __name__ == "__main__":
    main()