use chrono::Utc;
use sea_orm::{ActiveModelTrait, ColumnTrait, EntityTrait, QueryFilter, Set};
use std::time::Duration;

use erp_core::entity::domain_event;
use erp_core::events::{DomainEvent, EventBus};

/// 启动 outbox relay 后台任务。
///
/// 定期扫描 domain_events 表中 status = 'pending' 的事件，
/// 重新广播并标记为 published。
pub fn start_outbox_relay(db: sea_orm::DatabaseConnection, event_bus: EventBus) {
    tokio::spawn(async move {
        let mut interval = tokio::time::interval(Duration::from_secs(5));
        loop {
            interval.tick().await;
            if let Err(e) = process_pending_events(&db, &event_bus).await {
                tracing::warn!(error = %e, "Outbox relay 处理失败");
            }
        }
    });
}

async fn process_pending_events(
    db: &sea_orm::DatabaseConnection,
    event_bus: &EventBus,
) -> Result<(), sea_orm::DbErr> {
    let pending = domain_event::Entity::find()
        .filter(domain_event::Column::Status.eq("pending"))
        .filter(domain_event::Column::Attempts.lt(3))
        .all(db)
        .await?;

    if pending.is_empty() {
        return Ok(());
    }

    tracing::info!(count = pending.len(), "处理待发领域事件");

    for event_model in pending {
        // 重建 DomainEvent 并广播
        let domain_event = DomainEvent::new(
            &event_model.event_type,
            event_model.tenant_id,
            event_model.payload.clone().unwrap_or(serde_json::json!({})),
        );

        event_bus.broadcast(domain_event);

        // 标记为 published
        let mut active: domain_event::ActiveModel = event_model.into();
        active.status = Set("published".to_string());
        active.published_at = Set(Some(Utc::now()));
        active.update(db).await?;
    }

    Ok(())
}