use anyhow::Result;
use feedsignal_db::Db;

/// Re-fetches every subscribed feed and inserts any articles published since
/// the last run. `articles.url` is unique, so re-fetching the same feed and
/// inserting its (mostly already-seen) entries is safe — `insert_article`
/// silently skips ones already in the database, leaving only genuinely new
/// articles behind.
pub async fn run(db: &Db) -> Result<()> {
    let feeds = db.list_feeds().await?;
    tracing::info!(count = feeds.len(), "polling subscribed feeds");

    for (feed_id, url) in feeds {
        let (_title, articles) = match feedsignal_feeds::fetch_feed(&url, feed_id).await {
            Ok(result) => result,
            Err(err) => {
                tracing::warn!(?err, %url, "failed to poll feed, skipping");
                continue;
            }
        };

        for article in &articles {
            db.insert_article(article).await?;
        }
        db.mark_feed_fetched(feed_id).await?;
    }

    Ok(())
}