#!/usr/bin/env python3

# RECOMMENDATIONS
#
# 1. Backup your state file


import json
import urllib.request

import sys
import logging
from optparse import OptionParser
import os.path
import shutil


logging.basicConfig(level=logging.DEBUG)

def set_working_directory():
    import os
    new_wd = os.path.dirname(sys.argv[0])
    os.chdir(new_wd)
    logging.debug(new_wd)

set_working_directory()

STATE_FILE = "download_latest.state"
# PROJECT_URL = "signalapp/Signal-Desktop"

usage = "usage: download_latest.py [options] PROJECT_URL ARTIFACT_NAME ARCHIVE_FORMAT"
parser = OptionParser(usage)
parser.add_option("-n", "--name", default="", dest="subfolder", help="name of local subfolder")
parser.add_option("--log", default="DEBUG", dest="loglevel", help="loglevel")

(options, args) = parser.parse_args()

if len(args) != 3:
    print("Incorrect number of arguments!")
    print(usage)
    exit()

PROJECT_URL = args[0]
logging.debug(PROJECT_URL)
ARTIFACT_NAME = args[1]
logging.debug(ARTIFACT_NAME)
ARCHIVE_FORMAT = args[2]
logging.debug(ARCHIVE_FORMAT)

# logging.basicConfig(level=options.loglevel)

SUBFOLDER = PROJECT_URL.split("/")
logging.debug(f"SUBFOLDER={SUBFOLDER}")

if len(SUBFOLDER) != 2:
    print("Invalid project url {}: wrong number of slashes (1 expected)!")
    exit()

SUBFOLDER = SUBFOLDER[1]

if options.subfolder != "":
    SUBFOLDER = options.subfolder

logging.debug(SUBFOLDER)

# load state file
if os.path.isfile(STATE_FILE):
    with open(STATE_FILE) as f:
        STATE = json.loads("\n".join(f.readlines()))
else:
    STATE = {}


# read json api object from github

#logging.debug(urllib.request.urlopen("https://api.github.com/repos/{}/releases/latest".format(PROJECT_URL)).read())

json_response = json.loads(urllib.request.urlopen("https://api.github.com/repos/{}/releases/latest".format(PROJECT_URL)).read())

logging.debug(json_response['name'])

remote_version = json_response['name']
if SUBFOLDER in STATE:
    local_version = STATE[SUBFOLDER]
    if local_version == remote_version:
        print("remote version ({}) equals local version ({}). Nothing to do, quitting!".format(remote_version, local_version))
        exit()

if ARTIFACT_NAME not in json_response:
    print("Artifact name not in json response. Check please!")
    exit()

artifact_url = json_response[ARTIFACT_NAME]
local_pkg, headers  = urllib.request.urlretrieve(artifact_url)
logging.debug(f"local_pkg = {local_pkg}")

# remove old version
if os.path.isdir(SUBFOLDER):
    shutil.rmtree(SUBFOLDER)


# does not detect nested folders FIXME
match ARCHIVE_FORMAT:
    case "zip":
        import zipfile
        with zipfile.open(local_pkg) as z:
            z.extract_all(SUBFOLDER)

    case "tgz":
        import subprocess
        import os
        os.mkdir(SUBFOLDER)
        os.chdir(SUBFOLDER)
        rv = subprocess.call(["tar", "xf", local_pkg])
        os.chdir("..")

    case _:
        print(f"archive format {ARCHIVE_FORMAT} not known. Exiting!")
        exit()

STATE[SUBFOLDER] = remote_version

logging.debug(f"remote={remote_version};state={STATE[SUBFOLDER]}")


with open(STATE_FILE, 'w') as f:
    f.write(json.dumps(STATE))