<?php

/**
 * Event queue repository - persistence for async events.
 *
 * @package AfroIT_Messaging_WorkflowAutomations
 */

namespace AfroIT\Messaging\WorkflowAutomations\Async;


if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- custom plugin table afromewo_workflow_queue; no WP object-cache API for these rows.


/**
 * Class EventQueueRepository
 *
 * Handles storage and retrieval of queued events.
 */
final class EventQueueRepository {

	/**
	 * @var \wpdb
	 */
	private \wpdb $wpdb;

	/**
	 * Constructor.
	 *
	 * @param \wpdb|null $wpdb WordPress database instance.
	 */
	public function __construct( ?\wpdb $wpdb = null ) {
		$this->wpdb = $wpdb ?? $GLOBALS['wpdb'];
	}

	/**
	 * Enqueue an event.
	 *
	 * @param string $event_name  Event name (e.g. order_created).
	 * @param string $payload_json JSON-encoded payload.
	 * @return int|false Insert ID or false.
	 */
	public function enqueue( string $event_name, string $payload_json ) {
		$table = QueueTable::getTableName( $this->wpdb );

		$result = $this->wpdb->insert(
			$table,
			array(
				'event_name'   => $event_name,
				'payload_json' => $payload_json,
				'status'       => QueueTable::STATUS_PENDING,
				'created_at'   => current_time( 'mysql' ),
			),
			array( '%s', '%s', '%s', '%s' )
		);

		return $result ? (int) $this->wpdb->insert_id : false;
	}

	/**
	 * Fetch pending events for processing.
	 *
	 * @param int $limit Max events to fetch.
	 * @return array<int, object>
	 */
	public function fetchPending( int $limit = 20 ): array {
		$table = QueueTable::getTableName( $this->wpdb );
        $pending = QueueTable::STATUS_PENDING;
        $wpdb = $this->wpdb;

		$results = $wpdb->get_results( 
            $wpdb->prepare(
                "SELECT * FROM %i WHERE status = %s ORDER BY created_at ASC LIMIT %d",
                $table,
                $pending,
                $limit,
            ) 
        );

		return is_array( $results ) ? $results : array();
	}

	/**
	 * Whether any events are waiting to be processed.
	 *
	 * @return bool
	 */
	public function hasPending(): bool {
		$wpdb  = $this->wpdb;
		$table = QueueTable::getTableName( $wpdb );
		$found = $wpdb->get_var(
			$wpdb->prepare(
				'SELECT id FROM %i WHERE status = %s LIMIT 1',
				$table,
				QueueTable::STATUS_PENDING
			)
		);

		return null !== $found && '' !== (string) $found;
	}

	/**
	 * Mark event as processing (claim for worker).
	 *
	 * @param int $id Event ID.
	 * @return bool
	 */
	public function markProcessing( int $id ): bool {
		return $this->updateStatus( $id, QueueTable::STATUS_PROCESSING );
	}

	/**
	 * Mark event as processed.
	 *
	 * @param int $id Event ID.
	 * @return bool
	 */
	public function markProcessed( int $id ): bool {
		$table = QueueTable::getTableName( $this->wpdb );
		return (bool) $this->wpdb->update(
			$table,
			array(
				'status'       => QueueTable::STATUS_PROCESSED,
				'processed_at'  => current_time( 'mysql' ),
			),
			array( 'id' => $id ),
			array( '%s', '%s' ),
			array( '%d' )
		);
	}

	/**
	 * Mark event as failed.
	 *
	 * @param int $id Event ID.
	 * @return bool
	 */
	public function markFailed( int $id ): bool {
		return $this->updateStatus( $id, QueueTable::STATUS_FAILED );
	}

	/**
	 * Release an event back to pending for a later retry.
	 *
	 * @param int $id Event ID.
	 * @return bool
	 */
	public function releaseForRetry( int $id ): bool {
		return $this->updateStatus( $id, QueueTable::STATUS_PENDING );
	}

	/**
	 * Update event status.
	 *
	 * @param int    $id     Event ID.
	 * @param string $status Status.
	 * @return bool
	 */
	private function updateStatus( int $id, string $status ): bool {
		$table = QueueTable::getTableName( $this->wpdb );
		return (bool) $this->wpdb->update(
			$table,
			array( 'status' => $status ),
			array( 'id' => $id ),
			array( '%s' ),
			array( '%d' )
		);
	}
}