#!/usr/bin/python3

"""This script does a version comparison between the versions of packages
from the update under test and the installed versions of the same-named
packages, for whichever packages from the update are installed. It expects
input data that's generated in advisory_check_nonmatching_packages and
advisory_get_installed_packages; you can run it manually against
updatepkgs.txt and installedupdatepkgs.txt logs from a completed test run
if you need to test it or something."""

# no, pylint, global scope variable names in a script like this aren't
# really "constants"
# pylint:disable=invalid-name

import json
import sys
from urllib.request import urlopen

import rpm  # pylint:disable=import-error

def printver(pname, pepoch, pversion, prelease):
    """Print a NEVR in the typical human-readable format."""
    return f"{pname}-{pepoch}:{pversion}-{prelease}"

try:
    updfname = sys.argv[1]
    instfname = sys.argv[2]
except IndexError:
    sys.exit("Must specify two input filenames!")
try:
    updalias = sys.argv[3]
except IndexError:
    updalias = None


updpkgs = {}
with open(updfname, "r", encoding="utf-8") as ufh:
    for uline in ufh.readlines():
        (_, name, epoch, version, release) = uline.strip().split(" ")
        updpkgs[name] = (epoch, version, release)

problems = []
warnings = []
post = set()
ret = 0
updstable = None
with open(instfname, "r", encoding="utf-8") as ifh:
    for iline in ifh.readlines():
        (_, name, epoch, version, release) = iline.strip().split(" ")
        res = rpm.labelCompare((epoch, version, release), (updpkgs[name]))
        if res == 0:
            continue
        instver = printver(name, epoch, version, release)
        updver = printver(name, *updpkgs[name])
        if res < 0:
            problems.append(f"Installed: {instver} is older than update: {updver}.")
            post.add("Installed older than update usually means there is a dependency problem preventing the update version being installed.")
            post.add("Check /var/log/dnf.log, and search for the string 'Problem'.")
        else:
            msg = f"Installed: {instver} is newer than update: {updver}"
            if not updalias:
                problems.append(f"{msg} and this is not an update test, please check if this is a problem")
                continue
            # check if the update is stable
            if updstable is None:
                try:
                    url = f"https://bodhi.fedoraproject.org/updates/{updalias}"
                    resp = json.loads(urlopen(url).read().decode("utf8"))   # pylint:disable=consider-using-with
                    updstable = (resp.get("update", {}).get("status", "") == "stable")
                except: # pylint:disable=bare-except
                    problems.append(f"{msg} and Bodhi is unreachable.")
                    continue
            if updstable:
                warnings.append(f"{msg} and update is stable, this is probably OK.")
            else:
                problems.append(f"{msg} and update is not stable.")
                post.add("Installed newer than update and update not stable means older version could be pushed over newer if update goes stable.")

if warnings:
    print("WARNINGS")
    for warning in warnings:
        print(warning)
    ret = 2

if problems:
    print("PROBLEMS")
    for problem in problems:
        print(problem)
    ret = 3

if post:
    print("INVESTIGATION TIPS")
    for postmsg in post:
        print(postmsg)

sys.exit(ret)