<?php

declare(strict_types=1);

namespace FreshetBackup;

/**
 * What the last run did, for the screen and the notice. One option row, not
 * autoloaded. It holds outcomes and file names — never a path to a secret,
 * never a credential.
 *
 * It also keeps `success`: when a backup last worked, carried across later
 * failures. Without it the row forgets, and "nothing has worked in three days"
 * — the one thing a silently missed backup can be measured by — cannot be said
 * at all. See Health.
 */
final class Status
{
    public const OPTION = 'freshet_backup_status';

    /** @return array<string, mixed> */
    public function get(): array
    {
        $value = get_option(self::OPTION, []);

        return is_array($value) ? $value : [];
    }

    /** @param array<string, mixed> $run */
    public function record(array $run): void
    {
        $run += ['time' => time()];
        $success = ($run['outcome'] ?? '') === 'ok'
            ? (int) $run['time']
            : (int) $this->success();
        if ($success > 0) {
            $run['success'] = $success;
        }

        update_option(self::OPTION, $run, false);
    }

    /**
     * When a backup last worked, or null when none ever has. A row written by
     * 1.0.0 has no `success`; when its own run was a good one, that run's time
     * is the answer.
     */
    public function success(): ?int
    {
        $last = $this->get();
        $at = (int) ($last['success'] ?? 0);
        if ($at <= 0 && ($last['outcome'] ?? '') === 'ok') {
            $at = (int) ($last['time'] ?? 0);
        }

        return $at > 0 ? $at : null;
    }

    /** The message an admin notice should carry, or null when the last run is nothing to worry about. */
    public function problem(): ?string
    {
        $last = $this->get();

        return in_array($last['outcome'] ?? '', ['failed', 'refused', 'kept'], true) ? (string) ($last['message'] ?? '') : null;
    }
}