import argparse
import pkg_resources
from datetime import datetime
from distutils.version import LooseVersion

import requests
from packaging.version import LegacyVersion
from packaging.specifiers import SpecifierSet


def get_release_date(version):
    if not version:
        return None
    time = version[0]['upload_time']
    return datetime.fromisoformat(time)


def release_date_string(d):
    return 'Release date: {}'.format(d.strftime('%d/%m/%Y'))


def release_str(version):
    d = get_release_date(version)
    if d:
        return release_date_string(d)
    return


def get_latest(versions):
    versions.sort(reverse=True)
    for v in versions:
        if v.pre:
            continue
        return v


parser = argparse.ArgumentParser()
parser.add_argument("filename")
args = parser.parse_args()

with open(args.filename) as f:
    requirements = pkg_resources.parse_requirements(f.read())

    for r in requirements:
        print()
        print('package {}'.format(r.name))
        rsp = requests.get("https://pypi.org/pypi/{}/json".format(r.name))
        if rsp:
            response = rsp.json()
            versions = list(response["releases"].keys())
            if not versions:
                continue
            latest_version = get_latest([LegacyVersion(v) for v in versions])
            release = release_str(response["releases"][str(latest_version)])
            print('Latest: {} {}'.format(latest_version, release))
            if r.specifier:
                s = r.specifier
                filtered_versions = s.filter(versions)
                selected = list(filtered_versions)
                if selected:
                    release = release_str(response["releases"][str(selected[0])])
                    print('Current: {} {}'.format(selected[0], release))
                    continue

            release = release_str(response["releases"][str(versions[0])])
            print('Current: {} {}'.format(versions[0], release))