<?php
/**
 * Email report status per site.
 *
 * @package TurtleReport
 */

namespace TurtleReport\Email;

use TurtleReport\Support\OptionUpdate;

defined( 'ABSPATH' ) || exit;

/**
 * Remembers the next send time and the last result for each site.
 *
 * Kept apart from the site settings so saving a site never overwrites it.
 */
final class EmailLog {

	const OPTION = 'turtlereport_email_log';

	/**
	 * Status for a site.
	 *
	 * @param string $site_id Site ID.
	 * @return array{next:int,last_sent:int,last_error:string,last_count:int,retries:int}
	 */
	public function get( $site_id ) {
		$all = $this->all();
		$row = isset( $all[ $site_id ] ) && is_array( $all[ $site_id ] ) ? $all[ $site_id ] : array();
		return array_merge(
			array(
				'next'       => 0,
				'last_sent'  => 0,
				'last_error' => '',
				'last_count' => 0,
				'retries'    => 0,
			),
			$row
		);
	}

	/**
	 * Updates fields for a site.
	 *
	 * @param string $site_id Site ID.
	 * @param array  $fields  Fields to change.
	 * @return void
	 */
	public function update( $site_id, array $fields ) {
		OptionUpdate::change(
			self::OPTION,
			static function ( array $all ) use ( $site_id, $fields ) {
				$current         = isset( $all[ $site_id ] ) && is_array( $all[ $site_id ] ) ? $all[ $site_id ] : array();
				$all[ $site_id ] = array_merge( $current, $fields );
				return $all;
			}
		);
	}

	/**
	 * Forgets a site.
	 *
	 * @param string $site_id Site ID.
	 * @return void
	 */
	public function forget( $site_id ) {
		OptionUpdate::change(
			self::OPTION,
			static function ( array $all ) use ( $site_id ) {
				unset( $all[ $site_id ] );
				return $all;
			}
		);
	}

	/**
	 * Every status row.
	 *
	 * @return array
	 */
	private function all() {
		$all = get_option( self::OPTION, array() );
		return is_array( $all ) ? $all : array();
	}

	/**
	 * Drops WordPress's in-request copy of the log so the next read hits the database.
	 *
	 * @return void
	 */
	public function refresh() {
		wp_cache_delete( self::OPTION, 'options' );
		wp_cache_delete( 'notoptions', 'options' );
	}
}