Python

import configparser
from datetime import datetime
import glob
import re
import urllib.request
import os
import subprocess
import zipfile
import logging
from shutil import copy2

LOCAL_ARCHIVE    = "/archive/shaiya-gamigo"
PATCH_REGEX     = "^ps([0-9]{4})"
UPDATE_ENDPOINT = "http://shaiya-us.download.aeriagames.com"
UPDATE_HEADER    = "update.sah"
UPDATE_DATA    = "update.saf"
GAME_CLIENT    = "game.exe"

def init():
    logger = logging.getLogger("logging_tryout2")
    logger.setLevel(logging.INFO)

    formatter = logging.Formatter("%(asctime)s: %(message)s",
                              "%d-%m-%Y %H:%M:%S")

    ch = logging.FileHandler("download.log")
    ch.setFormatter(formatter)
    ch.setLevel(logging.INFO)
    logger.addHandler(ch)

    logger.info("Checking for updates...")
    local_patch = get_local_gamigo_patch(f"{LOCAL_ARCHIVE}/patches/*")
    remote_patch = get_remote_gamigo_patch()
    logger.info(f"Current archive patch={local_patch}, Current gamigo patch={remote_patch}")

    if local_patch >= remote_patch:
        logger.info("No new updates detected")

    for patch_number in range(local_patch+1, remote_patch+1):
        download_patch(logger, patch_number)

def download_patch(logger, patch_number):
    patch_name = f"ps{patch_number:04}"
    logger.info(f"Downloading {patch_name}...")
    endpoint = f"{UPDATE_ENDPOINT}/client/{patch_name}.patch"

    response = urllib.request.urlopen(endpoint)
    last_modified = response.headers["last-modified"]
    date = datetime.strptime(last_modified, "%a, %d %b %Y %H:%M:%S %Z")
    date_format = date.strftime("")

    dated_name = f"{patch_name}-{date.day}-{date.month}-{date.year}"
    patch_directory = f"{LOCAL_ARCHIVE}/patches/{dated_name}"
    os.mkdir(patch_directory)

    patch_path = f"{patch_directory}/{patch_name}.patch"
    patch_file = open(patch_path, "xb")    # x = create, b = bytes
    patch_file.write(response.read())
    patch_file.close()

    with zipfile.ZipFile(patch_path, "r") as zip_ref:
        logger.info(f"Extracting {patch_name} to {patch_directory}")
        zip_ref.extractall(patch_directory)

    # Extract the archive updates if needed.
    if os.path.isfile(f"{patch_directory}/{UPDATE_HEADER}"):
        logger.info(f"Extracting update archive (update.sah/saf) contents")
        subprocess.call(["openshaiya-extractor", f"--data={patch_directory}/{UPDATE_DATA}", f"--header={patch_directory}/{UPDATE_HEADER}", f"--output={patch_directory}"])
        os.remove(f"{patch_directory}/{UPDATE_DATA}")
        os.remove(f"{patch_directory}/{UPDATE_HEADER}")

    # Create a copy of the game client if it exists
    patch_client = f"{patch_directory}/{GAME_CLIENT}"
    if os.path.isfile(patch_client):
        dest_path = f"{LOCAL_ARCHIVE}/clients/{patch_name}-{date.day}-{date.month}-{date.year}-game.exe"
        logger.info(f"Copying new game client to {dest_path}")
        copy2(patch_client, dest_path)
    pass

def map_name_to_patch(name):
    last_index_slash = name.rfind("/")
    name = name[last_index_slash+1:last_index_slash+7]
    pattern = re.compile(PATCH_REGEX)
    result = pattern.search(name)
    return int(result.group(1))

def get_local_gamigo_patch(path):
    patches = list(map(map_name_to_patch, glob.glob(path)))
    patches.sort(reverse=True)
    return patches[0]

def get_remote_gamigo_patch():
    url = f"{UPDATE_ENDPOINT}/UpdateVersion.ini"
    response = urllib.request.urlopen(url)
    text = response.read().decode("utf-8")

    config = configparser.ConfigParser()
    config.read_string(text)

    return int(config["Version"]["PatchFileVersion"])

if __name__ == "__main__":
    init()