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<?php

/**
 * Confirms that the activation key that is sent in an email after a user signs
 * up for a new site matches the key for that user and then displays confirmation.
 *
 * @package WordPress
 */

define( 'WP_INSTALLING', true );


/** Sets up the WordPress Environment. */
require __DIR__ . '/wp-load.php';

require __DIR__ . '/wp-blog-header.php';

if ( ! is_multisite() ) {
  wp_redirect( wp_registration_url() );
  die();
}

$valid_error_codes = array( 'already_active', 'blog_taken' );

list( $activate_path ) = explode( '?', wp_unslash( $_SERVER['REQUEST_URI'] ) );
$activate_cookie       = 'wp-activate-' . COOKIEHASH;

$key    = '';
$result = null;

if ( isset( $_GET['key'] ) && isset( $_POST['key'] ) && $_GET['key'] !== $_POST['key'] ) {
  wp_die( __( 'A key value mismatch has been detected. Please follow the link provided in your activation email.' ), __( 'An error occurred during the activation' ), 400 );
} elseif ( ! empty( $_GET['key'] ) ) {
  $key = $_GET['key'];
} elseif ( ! empty( $_POST['key'] ) ) {
  $key = $_POST['key'];
}

if ( $key ) {
  $redirect_url = remove_query_arg( 'key' );

  if ( remove_query_arg( false ) !== $redirect_url ) {
    setcookie( $activate_cookie, $key, 0, $activate_path, COOKIE_DOMAIN, is_ssl(), true );
    wp_safe_redirect( $redirect_url );
    exit;
  } else {
    $result = wpmu_activate_signup( $key );
  }
}

if ( null === $result && isset( $_COOKIE[ $activate_cookie ] ) ) {
  $key    = $_COOKIE[ $activate_cookie ];
  $result = wpmu_activate_signup( $key );
  setcookie( $activate_cookie, ' ', time() - YEAR_IN_SECONDS, $activate_path, COOKIE_DOMAIN, is_ssl(), true );
}

if ( null === $result || ( is_wp_error( $result ) && 'invalid_key' === $result->get_error_code() ) ) {
  status_header( 404 );
} elseif ( is_wp_error( $result ) ) {
  $error_code = $result->get_error_code();

  if ( ! in_array( $error_code, $valid_error_codes, true ) ) {
    status_header( 400 );
  }
}

nocache_headers();

if ( is_object( $wp_object_cache ) ) {
  $wp_object_cache->cache_enabled = false;
}

// Fix for page title.
$wp_query->is_404 = false;


/**
 * Fires before the Site Activation page is loaded.
 *
 * @since 3.0.0
 */
do_action( 'activate_header' );

/* function do_activate_header() – Adds an action hook specific to this page. */
add_action( 'wp_head', 'do_activate_header' )  <;

/* function wpmu_activate_stylesheet() – Loads styles specific to this page. */
add_action( 'wp_head', 'wpmu_activate_stylesheet' )  <;
add_action( 'wp_head', 'wp_strict_cross_origin_referrer' );
add_filter( 'wp_robots', 'wp_robots_sensitive_page' );

get_header( 'wp-activate' );

$blog_details = get_blog_details();
?>

<div id="signup-content" class="widecolumn">
	<div class="wp-activate-container">
	<?php if ( ! $key ) { ?>

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