<?php
/**
 * TMDO_Slack_Notifier — Slack incoming webhook channel (v2.5.0 M15).
 *
 * Settings: wpdo_slack_enabled, wpdo_slack_webhook, wpdo_slack_throttle_hours,
 * wpdo_slack_severity. Webhook URL must start with https://hooks.slack.com/.
 *
 * @package WP_Data_Optimizer
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Slack channel.
 */
class TMDO_Slack_Notifier extends TMDO_Abstract_Notifier {

	/**
	 * Channel identifier used as option key prefix.
	 *
	 * @return string
	 */
	public static function channel_id(): string {
		return 'slack';
	}

	/**
	 * Build Slack-specific context (webhook URL).
	 *
	 * @return array|null Null if webhook URL is missing or invalid.
	 */
	public static function build_context(): ?array {
		$url = class_exists( 'TMDO_Crypto' )
			? TMDO_Crypto::get_option( 'wpdo_slack_webhook' )
			: (string) get_option( 'wpdo_slack_webhook', '' );
		if ( '' === $url || strpos( $url, 'https://hooks.slack.com/' ) !== 0 ) {
			return null;
		}
		return array( 'webhook_url' => $url );
	}

	/**
	 * Send alert via Slack incoming webhook.
	 *
	 * @param string $subject Alert subject / title.
	 * @param string $body    Alert body text.
	 * @param array  $context Channel context (webhook_url).
	 * @return bool True on HTTP 2xx response.
	 */
	public static function actually_send( string $subject, string $body, array $context ): bool {
		$url = (string) ( $context['webhook_url'] ?? '' );
		if ( '' === $url ) {
			return false;
		}
		// Slack mrkdwn — bold subject + plaintext body in code block for readability.
		$payload = wp_json_encode(
			array(
				'text' => "*{$subject}*\n```\n{$body}\n```",
			)
		);
		$resp    = wp_remote_post(
			$url,
			array(
				'headers'  => array( 'Content-Type' => 'application/json' ),
				'body'     => $payload,
				'timeout'  => 5,
				'blocking' => true,
			)
		);
		if ( is_wp_error( $resp ) ) {
			return false;
		}
		$code = (int) wp_remote_retrieve_response_code( $resp );
		return $code >= 200 && $code < 300;
	}
}