import json
import re
import urllib.error
import urllib.parse
import urllib.request

from envfile import env_value

IMDB_ID_PATTERN = re.compile(r"tt\d{7,9}")
OMDB_URL = "https://www.omdbapi.com/"
OMDB_DEMO_URL = "http://www.omdbapi.com/demo.aspx/"
RATE_LIMITED_STATUS = 401
MISSING_VALUE = "N/A"


def imdb_id(text: str) -> str | None:
    match = IMDB_ID_PATTERN.search(text)
    return match.group(0) if match else None


def title_url(identifier: str) -> str:
    return f"https://www.imdb.com/title/{identifier}/"


def request_json(url: str, parameters: dict) -> dict:
    with urllib.request.urlopen(f"{url}?{urllib.parse.urlencode(parameters)}", timeout=10) as response:
        return json.load(response)


def lookup(identifier: str) -> dict | None:
    api_key = env_value("OMDB_API_KEY")
    if not api_key:
        return None
    try:
        try:
            result = request_json(OMDB_URL, {"apikey": api_key, "i": identifier})
        except urllib.error.HTTPError as error:
            if error.code != RATE_LIMITED_STATUS:
                raise
            result = request_json(OMDB_DEMO_URL, {"i": identifier, "token": "demo"})
    except (OSError, ValueError):
        return None
    return result if result.get("Response") == "True" else None


def present(value: str | None) -> str | None:
    return value if value and value != MISSING_VALUE else None


def details(identifier: str) -> dict:
    result = lookup(identifier)
    if not result:
        raise ValueError(f"Could not look up {identifier} on OMDb. Check OMDB_API_KEY in .env")
    return {
        "name": present(result.get("Title")),
        "year": present(result.get("Year")),
        "genre": present(result.get("Genre")),
        "runtime": present(result.get("Runtime")),
        "plot": present(result.get("Plot")),
        "posterSource": present(result.get("Poster")),
    }