from __future__ import annotations

import sys
import traceback
from datetime import datetime, timedelta
from pathlib import Path
from typing import TYPE_CHECKING

import click
from reader import Feed, ParseError, Reader, StorageError, UpdateError, UpdateResult

from app.dependencies import get_reader

if TYPE_CHECKING:
    from collections.abc import Iterable


def add_broken_feed_to_csv(feed: Feed | UpdateResult | None) -> None:
    """Add a broken feed to a CSV file."""
    if feed is None:
        click.echo("Feed is None.", err=True)
        return

    with Path("broken_feeds.csv").open("a", encoding="utf-8") as f:
        f.write(f"{feed.url}\n")


@click.command()
def update_feeds() -> None:
    """Update all the feeds."""
    reader: Reader = get_reader()
    click.echo("Updating feeds...")

    all_feeds: Iterable[Feed] = reader.get_feeds(updates_enabled=True)
    feeds = []

    # Only get feeds that hasn't been updated in the last 30 minutes.
    for feed in all_feeds:
        if feed.last_updated:
            now: datetime = datetime.now(tz=feed.last_updated.tzinfo)
            delta: timedelta = now - feed.last_updated

            thirty_minutes: int = 60 * 30  # 30 minutes
            if delta.total_seconds() < thirty_minutes:
                feeds.append(feed)
        else:
            feeds.append(feed)

    click.echo(f"Feeds to update: {len(feeds)}")

    for feed in feeds:
        try:
            reader.update_feed(feed)
            click.echo(f"Updated feed: {feed.url}")
        except ParseError:
            # An error occurred while retrieving/parsing the feed.
            click.echo(f"Error parsing feed: {feed.url}", err=True)
        except UpdateError:
            # An error occurred while updating the feed.
            # Parent of all update-related exceptions.
            click.echo(f"Error updating feed: {feed.url}", err=True)
        except StorageError as e:
            # An exception was raised by the underlying storage.
            click.echo(f"Error updating feed: {feed.url}", err=True)
            click.echo(f"Storage error: {e}", err=True)
        except AssertionError:
            # An assertion failed.
            click.echo(f"Assertion error: {feed.url}", err=True)
            traceback.print_exc(file=sys.stderr)
            reader.disable_feed_updates(feed)
            add_broken_feed_to_csv(feed)

    click.echo("Feeds updated.")


if __name__ == "__main__":
    update_feeds()