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

from jsonfile import PROJECT_ROOT

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


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 omdb_api_key() -> str | None:
    if os.environ.get("OMDB_API_KEY"):
        return os.environ["OMDB_API_KEY"]
    if not ENV_FILE.exists():
        return None
    for line in ENV_FILE.read_text(encoding="utf-8").splitlines():
        key, _, value = line.partition("=")
        if key.strip() == "OMDB_API_KEY" and value.strip():
            return value.strip().strip("\"'")
    return None


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 = 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