import type { ResultSetHeader, RowDataPacket } from 'mysql2/promise';
import type { MySqlPool } from '../db/mysql.js';

export interface AppendOutboxEventInput {
  tenantId: string;
  aggregateType: string;
  aggregateId: string;
  eventType: string;
  idempotencyKey: string;
  payload: unknown;
  availableAt?: Date;
}

type SqlExecutor = Pick<MySqlPool, 'execute'>;

export class OutboxRepository {
  constructor(private readonly executor: SqlExecutor) {}

  async append(input: AppendOutboxEventInput): Promise<{ id: string; created: boolean }> {
    const [result] = await this.executor.execute<ResultSetHeader>(
      `INSERT IGNORE INTO qipai_outbox_events
        (tenant_id, aggregate_type, aggregate_id, event_type,
         idempotency_key, payload, available_at)
       VALUES (?, ?, ?, ?, ?, CAST(? AS JSON), ?)`,
      [
        input.tenantId,
        input.aggregateType,
        input.aggregateId,
        input.eventType,
        input.idempotencyKey,
        JSON.stringify(input.payload),
        input.availableAt ?? new Date()
      ]
    );
    if (result.insertId > 0) {
      return { id: String(result.insertId), created: true };
    }
    const [rows] = await this.executor.execute<Array<RowDataPacket & { id: string }>>(
      `SELECT id FROM qipai_outbox_events
       WHERE tenant_id = ? AND idempotency_key = ?`,
      [input.tenantId, input.idempotencyKey]
    );
    if (!rows[0]) throw new Error('Idempotent outbox lookup failed after duplicate insert.');
    return { id: String(rows[0].id), created: false };
  }

  async markPublished(eventId: string): Promise<boolean> {
    const [result] = await this.executor.execute<ResultSetHeader>(
      `UPDATE qipai_outbox_events
       SET status = 'PUBLISHED', published_at = UTC_TIMESTAMP(3),
           attempts = attempts + 1, last_error = NULL
       WHERE id = ? AND status = 'PENDING'`,
      [eventId]
    );
    return result.affectedRows === 1;
  }

  async markFailed(eventId: string, error: unknown, delayMs: number): Promise<boolean> {
    const message = error instanceof Error ? error.message : String(error);
    const [result] = await this.executor.execute<ResultSetHeader>(
      `UPDATE qipai_outbox_events
       SET available_at = DATE_ADD(UTC_TIMESTAMP(3), INTERVAL ? MICROSECOND),
           attempts = attempts + 1, last_error = ?
       WHERE id = ? AND status = 'PENDING'`,
      [delayMs * 1000, message.slice(0, 1000), eventId]
    );
    return result.affectedRows === 1;
  }
}