use super::{PgPool, Uuid};

/// Toggle endorsement: insert if missing, delete if exists. Returns true if now endorsed.
/// Uses a transaction to prevent race conditions between concurrent toggle requests.
#[tracing::instrument(skip_all)]
pub async fn toggle_endorsement(
    pool: &PgPool,
    post_id: Uuid,
    endorser_id: Uuid,
) -> Result<bool, sqlx::Error> {
    let mut tx = pool.begin().await?;

    let result = sqlx::query!(
        "INSERT INTO post_endorsements (post_id, endorser_id) VALUES ($1, $2) ON CONFLICT DO NOTHING",
        post_id,
        endorser_id,
    )
    .execute(&mut *tx)
    .await?;

    if result.rows_affected() == 0 {
        // Already existed; remove it
        sqlx::query!(
            "DELETE FROM post_endorsements WHERE post_id = $1 AND endorser_id = $2",
            post_id,
            endorser_id,
        )
        .execute(&mut *tx)
        .await?;
        tx.commit().await?;
        Ok(false)
    } else {
        tx.commit().await?;
        Ok(true)
    }
}