<?php
/**
 * Queue job value object.
 *
 * @package R2Clouder
 */

namespace R2Clouder\Queue;

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

/**
 * One row of the jobs table, with its JSON payload already decoded.
 *
 * Handlers receive this rather than a raw array so that a typo in a column name
 * is a fatal error during development instead of a silent null.
 */
final class Job {

	const TYPE_OFFLOAD  = 'offload';
	const TYPE_DELETE   = 'delete';
	const TYPE_PURGE    = 'purge';
	const TYPE_PULLBACK = 'pullback';
	const TYPE_CONVERT  = 'convert';

	const TYPE_MIGRATE_COPY   = 'migrate_copy';
	const TYPE_MIGRATE_POLL   = 'migrate_poll';
	const TYPE_MIGRATE_VERIFY = 'migrate_verify';

	/**
	 * Removes the local copies of an already-verified offload.
	 *
	 * Separate from `offload` on purpose: deleting a local file is only safe once
	 * every recorded variant has been confirmed present in the bucket, which is a
	 * different set of network calls made at a different time.
	 */
	const TYPE_CLEANUP = 'cleanup';

	const STATUS_PENDING = 'pending';
	const STATUS_CLAIMED = 'claimed';
	const STATUS_DONE    = 'done';
	const STATUS_FAILED  = 'failed';

	/**
	 * Row id.
	 *
	 * @var int
	 */
	public $id = 0;

	/**
	 * Attachment the job acts on, or 0 for jobs that are not attachment bound.
	 *
	 * @var int
	 */
	public $attachment_id = 0;

	/**
	 * Job type, one of the TYPE_* constants.
	 *
	 * @var string
	 */
	public $job_type = '';

	/**
	 * Current status, one of the STATUS_* constants.
	 *
	 * @var string
	 */
	public $status = self::STATUS_PENDING;

	/**
	 * Lower runs first.
	 *
	 * @var int
	 */
	public $priority = 10;

	/**
	 * Number of times the job has been claimed.
	 *
	 * @var int
	 */
	public $attempts = 0;

	/**
	 * Earliest GMT datetime at which the job may run.
	 *
	 * @var string
	 */
	public $available_at = '';

	/**
	 * GMT datetime of the most recent claim, or null.
	 *
	 * @var string|null
	 */
	public $claimed_at = null;

	/**
	 * GMT datetime at which the job reached a terminal status, or null.
	 *
	 * @var string|null
	 */
	public $finished_at = null;

	/**
	 * Message from the last failure.
	 *
	 * @var string
	 */
	public $last_error = '';

	/**
	 * Decoded payload.
	 *
	 * @var array<string,mixed>
	 */
	public $payload = array();

	/**
	 * GMT datetime the row was inserted.
	 *
	 * @var string
	 */
	public $created_at = '';

	/**
	 * Builds a job from a database row.
	 *
	 * @param array<string,mixed> $row Row as returned by `$wpdb->get_row( …, ARRAY_A )`.
	 * @return Job
	 */
	public static function from_row( array $row ): self {
		$job = new self();

		$job->id            = isset( $row['id'] ) ? (int) $row['id'] : 0;
		$job->attachment_id = isset( $row['attachment_id'] ) ? (int) $row['attachment_id'] : 0;
		$job->job_type      = isset( $row['job_type'] ) ? (string) $row['job_type'] : '';
		$job->status        = isset( $row['status'] ) ? (string) $row['status'] : self::STATUS_PENDING;
		$job->priority      = isset( $row['priority'] ) ? (int) $row['priority'] : 10;
		$job->attempts      = isset( $row['attempts'] ) ? (int) $row['attempts'] : 0;
		$job->available_at  = isset( $row['available_at'] ) ? (string) $row['available_at'] : '';
		$job->claimed_at    = isset( $row['claimed_at'] ) && null !== $row['claimed_at'] ? (string) $row['claimed_at'] : null;
		$job->finished_at   = isset( $row['finished_at'] ) && null !== $row['finished_at'] ? (string) $row['finished_at'] : null;
		$job->last_error    = isset( $row['last_error'] ) && null !== $row['last_error'] ? (string) $row['last_error'] : '';
		$job->created_at    = isset( $row['created_at'] ) ? (string) $row['created_at'] : '';

		$payload = array();

		if ( isset( $row['payload'] ) && is_string( $row['payload'] ) && '' !== $row['payload'] ) {
			$decoded = json_decode( $row['payload'], true );

			if ( is_array( $decoded ) ) {
				$payload = $decoded;
			}
		}

		$job->payload = $payload;

		return $job;
	}

	/**
	 * Returns a payload value.
	 *
	 * @param string $key           Payload key.
	 * @param mixed  $default_value Value returned when the key is absent.
	 * @return mixed
	 */
	public function get( $key, $default_value = null ) {
		return array_key_exists( $key, $this->payload ) ? $this->payload[ $key ] : $default_value;
	}

	/**
	 * Every recognised job type.
	 *
	 * @return string[]
	 */
	public static function types(): array {
		$core_types = array(
			self::TYPE_OFFLOAD,
			self::TYPE_DELETE,
			self::TYPE_PURGE,
			self::TYPE_PULLBACK,
			self::TYPE_CONVERT,
			self::TYPE_CLEANUP,
			self::TYPE_MIGRATE_COPY,
			self::TYPE_MIGRATE_POLL,
			self::TYPE_MIGRATE_VERIFY,
		);
		$types      = $core_types;

		/**
		 * Filters registered queue job types.
		 *
		 * @param string[] $types Job type slugs.
		 */
		$types = apply_filters( 'r2clouder_job_types', $types );

		if ( ! is_array( $types ) ) {
			return array();
		}

		$types = array_merge( $core_types, array_map( 'sanitize_key', $types ) );

		return array_values( array_unique( array_filter( $types ) ) );
	}

	/**
	 * Every recognised status.
	 *
	 * @return string[]
	 */
	public static function statuses(): array {
		return array(
			self::STATUS_PENDING,
			self::STATUS_CLAIMED,
			self::STATUS_DONE,
			self::STATUS_FAILED,
		);
	}
}