import json, os, sys, urllib.parse, urllib.request, urllib.error


def _cfg():
    return json.loads(os.environ.get("INTEGRATION_SECRETS", "{}"))


def _inputs():
    return json.loads(os.environ.get("INTEGRATION_INPUTS", "{}"))


def _base(cfg):
    return (str(cfg.get("base_url") or "https://config.private.zscaler.com")).rstrip("/")


def _token(cfg):
    form = urllib.parse.urlencode({
        "client_id": str(cfg.get("client_id", "")),
        "client_secret": str(cfg.get("client_secret", "")),
    }).encode("utf-8")
    req = urllib.request.Request(_base(cfg) + "/signin", data=form,
                                 headers={"Content-Type": "application/x-www-form-urlencoded",
                                          "Accept": "application/json"}, method="POST")
    with urllib.request.urlopen(req, timeout=60) as r:
        tok = json.loads(r.read())
    if not tok.get("access_token"):
        raise Exception("Sign-in failed: " + json.dumps(tok))
    return tok["access_token"]


def request(method, path, cfg, token, params=None):
    # path is relative to the customer config base, e.g. /application
    url = _base(cfg) + "/mgmtconfig/v1/admin/customers/" + str(cfg.get("customer_id", "")) + path
    if params:
        clean = {k: v for k, v in params.items() if v not in (None, "")}
        if clean:
            url += "?" + urllib.parse.urlencode(clean)
    headers = {"Authorization": "Bearer " + token, "Accept": "application/json"}
    req = urllib.request.Request(url, headers=headers, method=method)
    with urllib.request.urlopen(req, timeout=90) as r:
        raw = r.read()
        return json.loads(raw) if raw else {}


def _run(fn):
    try:
        cfg = _cfg()
        inputs = _inputs()
        token = _token(cfg)
        print(json.dumps(fn(cfg, token, inputs)))
    except urllib.error.HTTPError as e:
        print(json.dumps({"error": "HTTP " + str(e.code), "detail": e.read().decode("utf-8", "replace")}))
        sys.exit(1)
    except Exception as e:
        print(json.dumps({"error": str(e)}))
        sys.exit(1)


def main(cfg, token, inputs):
    page = inputs.get("page") or 1
    page_size = inputs.get("page_size") or 20
    return request("GET", "/server", cfg, token, params={"page": int(page), "pagesize": int(page_size)})


_run(main)
