<?php
/**
 * Scheduled events grouped by owner.
 *
 * @package Bloatwright
 */

namespace Bloatwright\Services;

use Bloatwright\Profiler\Owner;

/**
 * CronAnalyzer.
 */
class CronAnalyzer {

	/**
	 * Analyse.
	 *
	 * @return array{owners: array<string, array{per_day:float,events:array,min_interval_min:float}>, descriptors:array, orphans:array, total_per_day:float}
	 */
	public function analyze(): array {
		$crons     = function_exists( '_get_cron_array' ) ? (array) _get_cron_array() : array();
		$schedules = wp_get_schedules();
		if ( ! function_exists( 'get_plugins' ) ) {
			require_once ABSPATH . 'wp-admin/includes/plugin.php'; // Lists installed but inactive plugins as owners too.
		}
		$owner   = new Owner( (array) get_option( 'bloatwright_overrides', array() ) );
		$owners  = array();
		$desc    = array();
		$orphans = array();
		$total   = 0.0;
		global $wp_filter;
		foreach ( $crons as $timestamp => $hooks ) {
			foreach ( $hooks as $hook => $events ) {
				foreach ( (array) $events as $event ) {
					$schedule  = (string) ( $event['schedule'] ?? '' );
					$interval  = (int) ( $event['interval'] ?? ( $schedules[ $schedule ]['interval'] ?? 0 ) );
					$per_day   = $interval > 0 ? DAY_IN_SECONDS / $interval : 0.0; // One-off events count 0/day.
					$callbacks = array();
					if ( isset( $wp_filter[ $hook ] ) && $wp_filter[ $hook ] instanceof \WP_Hook ) {
						foreach ( $wp_filter[ $hook ]->callbacks as $cbs ) {
							foreach ( $cbs as $cb ) {
								$callbacks[] = $cb['function'];
							}
						}
					}
					$key = Owner::UNKNOWN;
					if ( $callbacks ) {
						$key = $owner->for_callable( $callbacks[0] );
					} elseif ( 0 === strpos( (string) $hook, 'wp_' ) || in_array( $hook, array( 'recovery_mode_clean_expired_keys', 'delete_expired_transients', 'wp_privacy_delete_old_export_files' ), true ) ) {
						$key = Owner::CORE;
					} else {
						$slug = PrefixRegistry::match( (string) $hook );
						if ( '' !== $slug ) {
							$key = 'plugin:' . $slug;
						}
						$orphans[] = array(
							'hook'     => (string) $hook,
							'schedule' => $schedule,
							'next'     => (int) $timestamp,
						);
					}
					if ( ! isset( $owners[ $key ] ) ) {
						$owners[ $key ] = array(
							'per_day'          => 0.0,
							'events'           => array(),
							'min_interval_min' => 0.0,
						);
						$desc[ $key ]   = $owner->describe( $key );
					}
					$owners[ $key ]['per_day'] += $per_day;
					$total                     += $per_day;
					if ( $interval > 0 ) {
						$mins                               = $interval / 60;
						$owners[ $key ]['min_interval_min'] = $owners[ $key ]['min_interval_min'] > 0 ? min( $owners[ $key ]['min_interval_min'], $mins ) : $mins;
					}
					$owners[ $key ]['events'][] = array(
						'hook'     => (string) $hook,
						'schedule' => '' !== $schedule ? $schedule : 'once',
						'interval' => $interval,
						'per_day'  => round( $per_day, 1 ),
						'next'     => (int) $timestamp,
						'callback' => ! empty( $callbacks ),
					);
				}
			}
		}
		foreach ( $owners as &$o ) {
			$o['per_day'] = round( $o['per_day'], 1 );
			usort(
				$o['events'],
				static function ( $a, $b ) {
					return $b['per_day'] <=> $a['per_day'];
				}
			);
		}
		unset( $o );
		uasort(
			$owners,
			static function ( $a, $b ) {
				return $b['per_day'] <=> $a['per_day'];
			}
		);
		return array(
			'owners'        => $owners,
			'descriptors'   => $desc,
			'orphans'       => $orphans,
			'total_per_day' => round( $total, 1 ),
		);
	}
}