<?php
/**
 * Plugin Name: SFP — Analytics (GA4)
 * Description: Injects the shared Google Analytics 4 gtag.js snippet on every front-end page. Symlinked into each demo via the platform mu-plugins fan-out. Skips admin, customizer preview, and any host that is not under philiprehberger.com.
 * Version: 1.0.0
 * Author: ScopeForged
 * Network: true
 */

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

/**
 * Shared GA4 measurement ID. One property covers every philiprehberger.com
 * subdomain (Next.js demos + WP tenants). GA4 treats them as a single site —
 * split per-tenant in reports via the built-in "Page hostname" dimension.
 */
const SFP_GA4_MEASUREMENT_ID = 'G-HZ8Z4XP611';

add_action('wp_head', function () {
    if (is_admin() || is_customize_preview()) {
        return;
    }

    // Defensive guard: this plugin is symlinked into every demo on the platform.
    // Only emit gtag for hosts under philiprehberger.com so we don't pollute the
    // GA property with traffic from other brands (e.g. scopeforged-library-wp).
    $host = isset($_SERVER['HTTP_HOST']) ? strtolower($_SERVER['HTTP_HOST']) : '';
    if ($host !== 'philiprehberger.com' && !str_ends_with($host, '.philiprehberger.com')) {
        return;
    }

    $id = SFP_GA4_MEASUREMENT_ID;
    if (empty($id) || $id === 'G-XXXXXXXXXX') {
        return;
    }
    ?>
    <!-- Google Analytics 4 (sfp-analytics) -->
    <script async src="https://www.googletagmanager.com/gtag/js?id=<?php echo esc_attr($id); ?>"></script>
    <script>
      window.dataLayer = window.dataLayer || [];
      function gtag(){dataLayer.push(arguments);}
      gtag('js', new Date());
      gtag('config', '<?php echo esc_js($id); ?>');
    </script>
    <?php
}, 1);