# Licence: GNU AGPL v3: http://www.gnu.org/licenses/
# This file is part of [`delarte`](https://git.afpy.org/fcode/delarte.git)

"""Provide ArteTV JSON API utilities."""

import json
from http import HTTPStatus
from urllib.request import urlopen


def load_api_data(url):
    """Retrieve the root node (infamous "data") of an API call response."""
    http_response = urlopen(url)

    if http_response.status != HTTPStatus.OK:
        raise RuntimeError("API request failed")

    if (
        http_response.getheader("Content-Type")
        != "application/vnd.api+json; charset=utf-8"
    ):
        raise ValueError("API response not supported")

    return json.load(http_response)["data"]


def load_config(lang, program_id):
    """Retrieve a program config from API."""
    url = f"https://api.arte.tv/api/player/v2/config/{lang}/{program_id}"
    config = load_api_data(url)

    if config["type"] != "ConfigPlayer":
        raise ValueError("Invalid API response")

    if config["attributes"]["metadata"]["providerId"] != program_id:
        raise ValueError("Invalid API response")

    return config


def iter_renditions(config):
    """Return a rendition (code, label) iterator."""
    for stream in config["attributes"]["streams"]:
        yield (
            # rendition code
            stream["versions"][0]["eStat"]["ml5"],
            # rendition full name
            stream["versions"][0]["label"],
        )


def select_rendition(config, rendition_code):
    """Return the master playlist index url for the given rendition code."""
    for stream in config["attributes"]["streams"]:
        if stream["versions"][0]["eStat"]["ml5"] == rendition_code:
            return stream["url"]

    return None