#!/usr/bin/env python3
import argparse
import os
import sys
from typing import Set

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 (
    get_environment,
    get_recent_deployments,
    parse_cache_script_args,
    purge_unused_caches,
)

ENV = get_environment()
NODE_MODULES_CACHE_PATH = "/srv/zulip-npm-cache"


def get_caches_in_use(threshold_days: int) -> Set[str]:
    setups_to_check = {ZULIP_PATH}
    caches_in_use = set()

    if ENV == "prod":
        setups_to_check |= get_recent_deployments(threshold_days)
    if ENV == "dev":
        # In dev always include the currently active cache in order
        # not to break current installation in case dependencies
        # are updated with bumping the provision version.
        CURRENT_CACHE = os.path.dirname(os.path.realpath(os.path.join(ZULIP_PATH, "node_modules")))
        caches_in_use.add(CURRENT_CACHE)

    for setup_dir in setups_to_check:
        node_modules_link_path = os.path.join(setup_dir, "node_modules")
        if not os.path.islink(node_modules_link_path):
            # If 'package.json' file doesn't exist then no node_modules
            # cache is associated with this setup.
            continue
        # The actual cache path doesn't include the /node_modules
        caches_in_use.add(os.path.dirname(os.readlink(node_modules_link_path)))

    return caches_in_use


def main(args: argparse.Namespace) -> None:
    caches_in_use = get_caches_in_use(args.threshold_days)
    purge_unused_caches(NODE_MODULES_CACHE_PATH, caches_in_use, "node modules cache", args)


if __name__ == "__main__":
    args = parse_cache_script_args("This script cleans unused Zulip npm caches.")
    main(args)