<?php
/**
 * One activity log entry.
 *
 * @package ForensixDigital
 */

declare(strict_types=1);

namespace ForensixDigital\Services\Activity;

defined( 'ABSPATH' ) || exit;

/**
 * Read-only snapshot of an activity row.
 */
final class ActivityRecord {

	public const DONE   = 'done';
	public const UNDONE = 'undone';
	public const FAILED = 'failed';

	/**
	 * Entry id.
	 *
	 * @var int
	 */
	public readonly int $id;

	/**
	 * User who made the change (0 for system jobs).
	 *
	 * @var int
	 */
	public readonly int $user_id;

	/**
	 * App id.
	 *
	 * @var string
	 */
	public readonly string $app;

	/**
	 * Action type, e.g. "scan.replace_link". Selects the undo handler.
	 *
	 * @var string
	 */
	public readonly string $action;

	/**
	 * Object type, e.g. "post".
	 *
	 * @var string
	 */
	public readonly string $object_type;

	/**
	 * Object id.
	 *
	 * @var string
	 */
	public readonly string $object_id;

	/**
	 * Plain-language description.
	 *
	 * @var string
	 */
	public readonly string $summary;

	/**
	 * State before the change.
	 *
	 * @var mixed
	 */
	public readonly mixed $before;

	/**
	 * State after the change.
	 *
	 * @var mixed
	 */
	public readonly mixed $after;

	/**
	 * Hash of the after-state, used to detect later edits before undoing.
	 *
	 * @var string
	 */
	public readonly string $after_hash;

	/**
	 * Status, one of the class constants.
	 *
	 * @var string
	 */
	public readonly string $status;

	/**
	 * Id of the entry this one undid, or 0.
	 *
	 * @var int
	 */
	public readonly int $undo_of;

	/**
	 * UTC time, "Y-m-d H:i:s".
	 *
	 * @var string
	 */
	public readonly string $created_at;

	/**
	 * Creates a snapshot.
	 *
	 * @param array $row Fields.
	 * @phpstan-param array{id: int, user_id: int, app: string, action: string, object_type: string, object_id: string, summary: string, before: mixed, after: mixed, after_hash: string, status: string, undo_of: int, created_at: string} $row
	 */
	public function __construct( array $row ) {
		$this->id          = $row['id'];
		$this->user_id     = $row['user_id'];
		$this->app         = $row['app'];
		$this->action      = $row['action'];
		$this->object_type = $row['object_type'];
		$this->object_id   = $row['object_id'];
		$this->summary     = $row['summary'];
		$this->before      = $row['before'];
		$this->after       = $row['after'];
		$this->after_hash  = $row['after_hash'];
		$this->status      = $row['status'];
		$this->undo_of     = $row['undo_of'];
		$this->created_at  = $row['created_at'];
	}

	/**
	 * Canonical hash of a state value.
	 *
	 * @param mixed $state State.
	 */
	public static function hash( mixed $state ): string {
		return hash( 'sha256', (string) wp_json_encode( $state ) );
	}
}