"""Enforce default Jellyfin user preferences via the API.

Iterates all users and sets preferFmp4HlsContainer in their
DisplayPreferences if not already enabled. Idempotent.
"""

import json
import os
import sys
import time
import urllib.request
from pathlib import Path

JELLYFIN_URL = os.environ.get("JELLYFIN_URL", "http://127.0.0.1:8096")


def get_api_key():
    cred_dir = os.environ["CREDENTIALS_DIRECTORY"]
    return Path(cred_dir, "jellyfin-api-key").read_text().strip()


def api(method, path, data=None):
    url = f"{JELLYFIN_URL}{path}"
    sep = "&" if "?" in url else "?"
    url += f"{sep}api_key={get_api_key()}"

    body = json.dumps(data).encode() if data else None
    req = urllib.request.Request(url, data=body, method=method)
    if body:
        req.add_header("Content-Type", "application/json")

    with urllib.request.urlopen(req) as resp:
        if resp.status == 204:
            return None
        return json.loads(resp.read())


def wait_healthy(timeout=120):
    deadline = time.monotonic() + timeout
    while time.monotonic() < deadline:
        try:
            req = urllib.request.Request(f"{JELLYFIN_URL}/health")
            with urllib.request.urlopen(req, timeout=5) as resp:
                if resp.read().decode().strip() == "Healthy":
                    return
        except Exception:
            pass
        time.sleep(2)
    print("Jellyfin did not become healthy in time", file=sys.stderr)
    sys.exit(1)


# Preferences to enforce: (key, desired_value)
DEFAULTS = [
    ("preferFmp4HlsContainer", "true"),
]


def main():
    wait_healthy()

    users = api("GET", "/Users")
    if not users:
        print("No users found, nothing to do")
        return

    for user in users:
        user_id = user["Id"]
        name = user["Name"]

        prefs = api(
            "GET",
            f"/DisplayPreferences/usersettings?userId={user_id}&client=emby",
        )
        custom = prefs.get("CustomPrefs", {})

        changed = False
        for key, value in DEFAULTS:
            if custom.get(key) != value:
                custom[key] = value
                changed = True

        if not changed:
            print(f"{name}: already up to date")
            continue

        prefs["CustomPrefs"] = custom
        api(
            "POST",
            f"/DisplayPreferences/usersettings?userId={user_id}&client=emby",
            prefs,
        )
        print(f"{name}: updated preferences")


if __name__ == "__main__":
    main()