<?php
namespace Relay\Notify;

use Relay\Support\RelayError;

/**
 * Who hears about finished jobs (spec §3.4): email recipients, a webhook URL (JSON with a Slack-compatible
 * "text"), and which events. Both channels are off until switched on.
 */
final class NotificationSettings
{
    public const OPTION = 'relay_notifications';
    public const EVENTS = ['job.completed', 'job.failed', 'incoming.pull', 'incoming.push'];
    private const MAX_RECIPIENTS = 10;

    public function get(): array
    {
        $stored = get_site_option(self::OPTION, []);
        $stored = is_array($stored) ? $stored : [];
        $events = [];
        foreach (self::EVENTS as $event) {
            $events[$event] = (bool) ($stored['events'][$event] ?? true);
        }
        return [
            'email' => ['on' => !empty($stored['email']['on']), 'to' => (string) ($stored['email']['to'] ?? get_site_option('admin_email', ''))],
            'webhook' => ['on' => !empty($stored['webhook']['on']), 'url' => (string) ($stored['webhook']['url'] ?? '')],
            'events' => $events,
        ];
    }

    /** @param mixed $input */
    public function save($input): array
    {
        $in = is_array($input) ? $input : [];
        $current = $this->get();
        $email = is_array($in['email'] ?? null) ? $in['email'] + $current['email'] : $current['email'];
        $webhook = is_array($in['webhook'] ?? null) ? $in['webhook'] + $current['webhook'] : $current['webhook'];
        $to = self::recipients((string) $email['to']);
        if (!empty($email['on']) && $to === []) {
            throw new RelayError('notify.email_invalid', esc_html__('Enter at least one valid email address.', 'siterelay'));
        }
        $url = trim((string) $webhook['url']);
        if ($url !== '' && !preg_match('#^https?://[^\s/?\#]+#i', $url)) {
            throw new RelayError('notify.webhook_invalid', esc_html__('The webhook URL must start with https:// (or http://).', 'siterelay'));
        }
        if (!empty($webhook['on']) && $url === '') {
            throw new RelayError('notify.webhook_invalid', esc_html__('Enter the webhook URL.', 'siterelay'));
        }
        $events = [];
        foreach (self::EVENTS as $event) {
            $events[$event] = array_key_exists($event, (array) ($in['events'] ?? [])) ? !empty($in['events'][$event]) : $current['events'][$event];
        }
        $value = ['email' => ['on' => !empty($email['on']), 'to' => implode(', ', $to)], 'webhook' => ['on' => !empty($webhook['on']), 'url' => esc_url_raw($url)], 'events' => $events];
        update_site_option(self::OPTION, $value);
        return $this->get();
    }

    /** @return string[] valid addresses from "a@x.org, b@y.org" (commas, semicolons or spaces) */
    public static function recipients(string $list): array
    {
        $out = [];
        foreach (preg_split('/[\s,;]+/', $list) ?: [] as $address) {
            $address = sanitize_email($address);
            if ($address !== '' && is_email($address) && !in_array($address, $out, true)) {
                $out[] = $address;
            }
        }
        return array_slice($out, 0, self::MAX_RECIPIENTS);
    }
}