use sea_orm_migration::prelude::*;

#[derive(DeriveMigrationName)]
pub struct Migration;

#[async_trait::async_trait]
impl MigrationTrait for Migration {
    async fn up(&self, manager: &SchemaManager) -> Result<(), DbErr> {
        manager
            .create_table(
                Table::create()
                    .table(Alias::new("processed_events"))
                    .if_not_exists()
                    .col(ColumnDef::new(Alias::new("event_id")).uuid().not_null())
                    .col(
                        ColumnDef::new(Alias::new("consumer_id"))
                            .string_len(200)
                            .not_null(),
                    )
                    .col(
                        ColumnDef::new(Alias::new("processed_at"))
                            .timestamp_with_time_zone()
                            .not_null()
                            .default(Expr::current_timestamp()),
                    )
                    .primary_key(
                        Index::create()
                            .col(Alias::new("event_id"))
                            .col(Alias::new("consumer_id")),
                    )
                    .to_owned(),
            )
            .await?;

        // 7 天 TTL 清理函数
        manager
            .get_connection()
            .execute_unprepared(
                r#"
                CREATE OR REPLACE FUNCTION cleanup_old_processed_events(
                    retention_days INT DEFAULT 7,
                    batch_size INT DEFAULT 1000
                ) RETURNS INT AS $$
                DECLARE
                    deleted_count INT;
                BEGIN
                    DELETE FROM processed_events
                    WHERE ctid IN (
                        SELECT ctid FROM processed_events
                        WHERE processed_at < NOW() - (retention_days || ' days')::INTERVAL
                        LIMIT batch_size
                    );

                    GET DIAGNOSTICS deleted_count = ROW_COUNT;
                    RETURN deleted_count;
                END;
                $$ LANGUAGE plpgsql;
                "#,
            )
            .await?;

        Ok(())
    }

    async fn down(&self, manager: &SchemaManager) -> Result<(), DbErr> {
        manager
            .get_connection()
            .execute_unprepared("DROP FUNCTION IF EXISTS cleanup_old_processed_events(INT, INT);")
            .await?;

        manager
            .drop_table(
                Table::drop()
                    .table(Alias::new("processed_events"))
                    .to_owned(),
            )
            .await?;

        Ok(())
    }
}