import requests
import json
import sys
from os.path import exists

def login(username, password):
    print("> Login for user "+username)
    payload = {'username': username, 'password': password, 'api_version':'4'}
    headers = {'content-type': 'application/json'}

    r = requests.post("https://auth.factorio.com/api-login", data=payload)

    return r.json()["token"]


def downloadRelease(releaseInfo, username, token):
    downloadURL = "https://mods.factorio.com"+releaseInfo["download_url"]+"?username="+username+"&token="+token
    r = requests.get(downloadURL)
    with open(releaseInfo["file_name"], "wb") as f:
        f.write(r.content)

def checkReleaseExistsOnHDD(releaseInfo):
    file_exists = exists(releaseInfo["file_name"])
    return file_exists

def getReleaseInfo(name, version):
    print("> Get Release Info")
    r = requests.get('https://mods.factorio.com/api/mods/'+name)
    data = r.json()
    if version == "latest":
        return data["releases"][-1]
    
    for r in data["releases"]:
        if r["version"] == version:
            return r

    sys.exit(200)


r = getReleaseInfo(sys.argv[1], sys.argv[2])
if checkReleaseExistsOnHDD(r) == False:
    token = login(sys.argv[3], sys.argv[4])
    downloadRelease(r, sys.argv[3], token)