Mabengoogly updater thinger

#Mabengoogly updater thinger.
#Lots of Googling needed because I don't know Python but it was the best for this job.
#Inconsistent variable naming scheme ahoy because of lazy copy-pasting.
#I like turtles.  Always remember this.

#Get some functions.
#Nomenclature.
import urllib.request
import urllib.error
import zlib
import base64
import json
import os
import sys

#Ask the user what version of the game they want to grab info for.
v_version = sys.argv[1]
print("")
#Get the manifest hashy thing for that version of the game (10200 = Mabinogi).
v_url = 'https://download2.nexon.net/Game/nxl/games/10200/10200.' + v_version + 'R.manifest.hash'
print(v_url)

#Read that file to see the next filename (actual manifest).
#Yes, the hash that shows up is the actual filename in the same directory.
v_hashfile = urllib.request.urlopen(v_url).read()
v_hashfile = v_hashfile.decode('utf8')

#Grab the actual manifest now (that hash filename).
v_url = 'https://download2.nexon.net/Game/nxl/games/10200/' + v_hashfile
print(v_url)
print("Manifest downloaded.")
v_filelist = urllib.request.urlopen(v_url).read()

#Now we need to uncompress the manifest.
#It has the list of files, packs, mp3s, dlls, etc.
v_manifestcontents = zlib.decompress(v_filelist)
print("Manifest decompressed.\n")

#Ask the user if they want to save the manifest.
v_dumpmanifest = 'y'

#If the user said yes, save it.
if v_dumpmanifest in ('y', 'Y', 'yes', 'Yes'):
    with open("manifest.txt", 'wb') as f:
        f.write(v_manifestcontents)
        print("Saved as .\\manifest.txt")

#It's JSON, so load it and junk.
v_manifestcontents = json.loads(v_manifestcontents.decode('utf8'))
#Use the encoding specified in the manifest file.
#Because readable text is important.
v_manifestencodingtype = v_manifestcontents['filepath_encoding']

#Ask the user what they want to do with this info.

print("")

#If we're going to dump the filename list...

v_filelist = []
for encoded_filename, contents in v_manifestcontents['files'].items():
    #Gotta' decode the names.
    filename = base64.b64decode(encoded_filename).decode(v_manifestencodingtype)
    v_filelist.append(filename)
#Sort the file list because it's in a crazy jumble normally.
with open('filelist.txt', 'w') as f:
    f.write('\n'.join(list(sorted(v_filelist))))
print("Saved as filelist.txt.")

#Ask for a specific file, find it, download the parts, merge them and save it.

v_goalfile = sys.argv[2]
print("")
#Loop through to get the parts.
for encoded_filename, contents in v_manifestcontents['files'].items():
    #The filenames in the manifest are base64 encoded, gotta' deal with that.
    filename = base64.b64decode(encoded_filename).decode(v_manifestencodingtype)
    #If it's the file the user requested...
    if filename == v_goalfile:
        #Files may be split up.
        v_piecedpatch = b""
        for item in contents['objects']:
            #Construct the download URL for each part of the file.
            v_parturl = 'https://download2.nexon.net/Game/nxl/games/10200/10200/' + item[:2] + "/" + item
            print(v_parturl)
            #Download and uncompress each part, append them together (binary join like copy /b).
            v_piecedpatch += zlib.decompress(urllib.request.urlopen(v_parturl).read())

        #Make the directory if needed, save the resulting file.
        os.makedirs(os.path.dirname(filename),exist_ok=True)
        with open(filename, 'wb') as f:
            f.write(v_piecedpatch)
        print("Saved as .\\"+filename)