<?php
/**
 * Plugin Name: Admin Bar Server Info
 * Description: Displays essential server and environment information directly in the WordPress admin bar for administrators.
 * Version: 1.0.2
 * Author: Raúl Fernández
 * Author URI: https://clink.es
 * License: GPLv2 or later
 * License URI: https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain: admin-bar-server-info
 * Domain Path: /languages
 * Requires at least: 5.0
 * Requires PHP: 7.4
 */

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Main plugin class.
 *
 * @since 1.0.0
 */
class Admin_Bar_Server_Info {

	/**
	 * Plugin version.
	 *
	 * @since 1.0.0
	 * @var string
	 */
	const VERSION = '1.0.2';

	/**
	 * Initialize the plugin.
	 *
	 * @since 1.0.0
	 */
	public function __construct() {
		// Hook into admin bar menu with high priority to appear on the right side.
		add_action( 'admin_bar_menu', array( $this, 'add_server_info_to_admin_bar' ), 999 );
	}

	/**
	 * Add server information to the admin bar.
	 *
	 * @since 1.0.0
	 * @param WP_Admin_Bar $wp_admin_bar The admin bar object.
	 */
	public function add_server_info_to_admin_bar( $wp_admin_bar ) {
		// Only show for administrators.
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}

		// Get server information.
		$server_info = $this->get_server_info();

		// Build the title with server information.
		$title = sprintf(
			/* translators: 1: PHP version, 2: Database version, 3: Server software, 4: WordPress version */
			esc_html__( '* PHP %1$s | %2$s | %3$s | WP %4$s *', 'admin-bar-server-info' ),
			esc_html( $server_info['php_version'] ),
			esc_html( $server_info['db_version'] ),
			esc_html( $server_info['server_software'] ),
			esc_html( $server_info['wp_version'] )
		);

		// Add menu item to admin bar (right side).
		// Using 'top-secondary' as parent ensures it appears on the right side.
		$wp_admin_bar->add_node(
			array(
				'id'     => 'abs_server_info',
				'title'  => $title,
				'parent' => 'top-secondary',
				'meta'   => array(
					'title' => '',
					'class' => 'abs-server-info',
				),
			)
		);
	}

	/**
	 * Get server and environment information.
	 *
	 * @since 1.0.0
	 * @return array Array containing server information.
	 */
	private function get_server_info() {
		global $wpdb;

		$info = array();

		// Get PHP version.
		$info['php_version'] = $this->get_php_version();

		// Get database version.
		$info['db_version'] = $this->get_database_version( $wpdb );

		// Get server software.
		$info['server_software'] = $this->get_server_software();

		// Get WordPress version.
		$info['wp_version'] = get_bloginfo( 'version' );

		return $info;
	}

	/**
	 * Get PHP version.
	 *
	 * @since 1.0.0
	 * @return string PHP version.
	 */
	private function get_php_version() {
		$php_version = PHP_VERSION;

		// Extract major and minor version (e.g., "8.2" from "8.2.15").
		$version_parts = explode( '.', $php_version );
		if ( count( $version_parts ) >= 2 ) {
			return $version_parts[0] . '.' . $version_parts[1];
		}

		return $php_version;
	}

	/**
	 * Get database version.
	 *
	 * @since 1.0.0
	 * @param wpdb $wpdb WordPress database object.
	 * @return string Database version.
	 */
	private function get_database_version( $wpdb ) {
		// Get full database version using SQL query for better detection.
		$db_version_full = $wpdb->get_var( 'SELECT VERSION()' );

		if ( empty( $db_version_full ) ) {
			// Fallback to WordPress db_version() method.
			$db_version_full = $wpdb->db_version();
		}

		if ( empty( $db_version_full ) ) {
			return esc_html__( 'Unknown', 'admin-bar-server-info' );
		}

		// Check if it's MariaDB (case-insensitive search).
		$is_mariadb = ( stripos( $db_version_full, 'mariadb' ) !== false );

		// Extract version numbers (major.minor).
		// MariaDB version format: "10.11.2-MariaDB" or similar.
		// MySQL version format: "8.0.35" or similar.
		preg_match( '/(\d+)\.(\d+)/', $db_version_full, $matches );
		
		if ( ! empty( $matches ) && count( $matches ) >= 3 ) {
			$major = $matches[1];
			$minor = $matches[2];
			$db_type = $is_mariadb ? 'MariaDB' : 'MySQL';
			return $db_type . ' ' . $major . '.' . $minor;
		}

		// Fallback: return as-is with detected type.
		$db_type = $is_mariadb ? 'MariaDB' : 'MySQL';
		return $db_type . ' ' . $db_version_full;
	}

	/**
	 * Get server software name.
	 *
	 * @since 1.0.0
	 * @return string Server software name.
	 */
	private function get_server_software() {
		// Check if SERVER_SOFTWARE is available.
		if ( ! isset( $_SERVER['SERVER_SOFTWARE'] ) || empty( $_SERVER['SERVER_SOFTWARE'] ) ) {
			return esc_html__( 'Unknown', 'admin-bar-server-info' );
		}

		$server_software = sanitize_text_field( wp_unslash( $_SERVER['SERVER_SOFTWARE'] ) );

		// Detect common server software.
		if ( stripos( $server_software, 'apache' ) !== false ) {
			return 'Apache';
		} elseif ( stripos( $server_software, 'nginx' ) !== false ) {
			return 'Nginx';
		} elseif ( stripos( $server_software, 'litespeed' ) !== false ) {
			return 'LiteSpeed';
		} elseif ( stripos( $server_software, 'iis' ) !== false ) {
			return 'IIS';
		} elseif ( stripos( $server_software, 'caddy' ) !== false ) {
			return 'Caddy';
		}

		// If no known server detected, return first part of SERVER_SOFTWARE.
		$parts = explode( '/', $server_software );
		if ( ! empty( $parts[0] ) ) {
			return esc_html( trim( $parts[0] ) );
		}

		return esc_html__( 'Unknown', 'admin-bar-server-info' );
	}
}

/**
 * Initialize the plugin.
 *
 * @since 1.0.0
 */
function abs_init() {
	new Admin_Bar_Server_Info();
}
add_action( 'init', 'abs_init' );