import logging
from datetime import datetime
from typing import cast
from xml.parsers.expat import ExpatError

import pytz
from rss_parser import Parser as RSSParser
from rss_parser.models.rss import RSS

from core.enums import ActivityName
from data.activity_ref import ActivityRef
from data.alert import Alert
from providers.alert.http_alert_provider import HTTPAlertProvider

logger = logging.getLogger(__name__)


class WOTA(HTTPAlertProvider):
    """Alert provider for Wainwrights on the Air"""

    POLL_INTERVAL_SEC = 1800
    ALERTS_URL = "https://www.wota.org.uk/alerts_rss.php"
    RSS_DATE_TIME_FORMAT = "%a, %d %b %Y %H:%M:%S %z"

    def __init__(self, provider_config):
        super().__init__("WOTA", provider_config, self.ALERTS_URL, self.POLL_INTERVAL_SEC)

    def _http_response_to_alerts(self, http_response):
        new_alerts = []

        try:
            rss = cast(RSS, RSSParser.parse(http_response.content.decode("utf-8-sig")))
            # Iterate through source data
            for source_alert in rss.channel.items:
                # Reject GUID missing or zero
                if (
                    not source_alert.guid
                    or not source_alert.guid.content
                    or source_alert.guid.content == "http://www.wota.org.uk/alerts/0"
                ):
                    continue

                # Pick apart the title
                dx_call = None
                ref = None
                ref_name = None
                try:
                    title_split = source_alert.title.split(" on ")
                    dx_call = title_split[0]
                    if len(title_split) > 1:
                        ref_split = title_split[1].split(" - ")
                        ref = str(ref_split[0])
                        if len(ref_split) > 1:
                            ref_name = str(ref_split[1])
                except Exception:
                    logger.warning(f"Could not parse WOTA alert title: {source_alert.description}", exc_info=True)

                # Pick apart the description
                comment = None
                freqs_modes = None
                try:
                    desc_split = source_alert.description.split(". ")
                    freqs_modes = desc_split[0].replace("Frequencies/modes:", "").strip()
                    if len(desc_split) > 1:
                        comment = desc_split[1].strip()
                except Exception:
                    logger.warning(f"Could not parse WOTA alert description: {source_alert.description}", exc_info=True)

                time = datetime.strptime(source_alert.pub_date.content, self.RSS_DATE_TIME_FORMAT).astimezone(pytz.UTC)

                # Convert to our alert format
                alert = Alert(
                    source=self.name,
                    source_id=source_alert.guid.content,
                    dx_calls=[dx_call],
                    freqs_modes=freqs_modes,
                    comment=comment,
                    sig_refs=[ActivityRef(id=ref, sig=ActivityName.WOTA, name=ref_name)] if ref else [],
                    start_time=time.timestamp(),
                )

                # Add to our list.
                new_alerts.append(alert)

        except ExpatError:
            logger.warning("WOTA alert RSS feed was fetched but was invalid")

        return new_alerts