import re
import requests
from datetime import datetime, timezone

from ..common.innertube import G

def fetch_ajax(endpoint, **kwargs):
    """
    fetch data using a continuation protobuf
    """
    # TODO: handle auto_generated!
    today = datetime.now(timezone.utc).strftime("%Y%m%d")

    # TODO: this is not cached any more! -> https://github.com/reclosedev/requests-cache/issues/154
    # TODO: replace host with youtubei.googleapis.com (used by android)?
    r = requests.post(f"https://www.youtube.com/youtubei/v1/{endpoint}?key=AIzaSyAO_FJ2SlqU8Q4STEHLGCilw_Y9_11qcW8", json={
        **kwargs,
        'context': {'client': {
            'gl': 'US',
            'hl': 'en',
            'clientName': 'WEB',
            'clientVersion': f'2.{today}.01.01',
        }},
    })

    if not r.ok:
        return None

    return r.json()

def canonicalize_channel(path):
    if re.fullmatch(r"(UC[A-Za-z0-9_-]{22})", path):
        return path

    # Note: for /watch, append query string, then return .endpoint.watchEndpoint.videoId
    resolved = fetch_ajax("navigation/resolve_url", url=f"https://www.youtube.com/{path}")
    channel_id = resolved.get('endpoint',{}).get('browseEndpoint',{}).get('browseId')
    return channel_id

def find_and_parse_error(result):
    error_obj = (
        result|G('responseContext')|G('errors')|G('error')|G(0)
        or result|G('alerts')|G(0)|G('alertRenderer')
        or result|G('error')
    )
    if error_obj is None:
        return None

    error_type = error_obj|G('code', 'type', 'status') or 'Error'
    error = (
        error_obj|G('debugInfo', 'externalErrorMessage')
        or error_obj|G('text')|G.text
        or error_obj|G('message')
        or "unknown error"
    )
    return f"{error_type}: {error.rstrip('.')}"