<?php
/**
 * Counts Canada Post failures in a row, so the admin hears about a broken
 * connection after a few failed checkouts instead of from a customer.
 *
 * A success resets the count. Stored in one small option, not autoloaded.
 */

declare(strict_types=1);

namespace BlueBrainMedia\MapleParcel\Support;

defined( 'ABSPATH' ) || exit;

final class Health {

	public const OPTION = 'bbmmp_health';

	/** When checkout first got a live rate (a timestamp, set once). The free build's Pro notice waits on it. */
	public const FIRST_RATE = 'bbmmp_first_rate_at';

	/** Failures in a row before the admin notice shows. */
	public const THRESHOLD = 3;

	public static function recordFailure( string $message ): void {
		$state = self::state();

		update_option(
			self::OPTION,
			array(
				'failures' => $state['failures'] + 1,
				'message'  => $message,
				'at'       => time(),
			),
			false
		);
	}

	public static function recordSuccess(): void {
		if ( 0 !== self::state()['failures'] ) {
			delete_option( self::OPTION );
		}
	}

	/** Autoloaded, so checkout asks the database nothing once it is set. */
	public static function noteFirstRate(): void {
		if ( 0 === self::firstRateAt() ) {
			update_option( self::FIRST_RATE, time(), true );
		}
	}

	public static function firstRateAt(): int {
		return (int) get_option( self::FIRST_RATE, 0 );
	}

	public static function isFailing(): bool {
		return self::state()['failures'] >= self::THRESHOLD;
	}

	/** @return array{failures: int, message: string, at: int} */
	public static function state(): array {
		$saved = get_option( self::OPTION, array() );
		$saved = is_array( $saved ) ? $saved : array();

		return array(
			'failures' => (int) ( $saved['failures'] ?? 0 ),
			'message'  => (string) ( $saved['message'] ?? '' ),
			'at'       => (int) ( $saved['at'] ?? 0 ),
		);
	}
}