/**
 * Add to cart messages.
 *
 * @access public
 * @param int|array $products
 * @param bool $show_qty Should qty's be shown? Added in 2.6.0
 */
function wc_add_to_cart_message($products, $show_qty = false)
{
    $titles = array();
    $count = 0;
    if (!is_array($products)) {
        $products = array($products);
        $show_qty = false;
    }
    if (!$show_qty && !is_array($products)) {
        $products = array_fill_keys(array_values($products), 1);
    }
    foreach ($products as $product_id => $qty) {
        $titles[] = ($qty > 1 ? absint($qty) . ' × ' : '') . sprintf(_x('“%s”', 'Item name in quotes', 'woocommerce'), strip_tags(get_the_title($product_id)));
        $count += $qty;
    }
    $titles = array_filter($titles);
    $added_text = sprintf(_n('%s has been added to your cart.', '%s have been added to your cart.', $count, 'woocommerce'), wc_format_list_of_items($titles));
    // Output success messages
    if ('yes' === get_option('woocommerce_cart_redirect_after_add')) {
        $return_to = apply_filters('woocommerce_continue_shopping_redirect', wp_get_raw_referer() ? wp_validate_redirect(wp_get_raw_referer(), false) : wc_get_page_permalink('shop'));
        $message = sprintf('<a href="%s" class="button wc-forward">%s</a> %s', esc_url($return_to), esc_html__('Continue Shopping', 'woocommerce'), esc_html($added_text));
    } else {
        $message = sprintf('<a href="%s" class="button wc-forward">%s</a> %s', esc_url(wc_get_page_permalink('cart')), esc_html__('View Cart', 'woocommerce'), esc_html($added_text));
    }
    wc_add_notice(apply_filters('wc_add_to_cart_message', $message, $product_id));
}

/**
 * Retrieves unvalidated referer from '_wp_http_referer' or HTTP referer.
 *
 * Do not use for redirects, use {@see wp_get_referer()} instead.
 *
 * @since 2.6.1
 * @return string|false Referer URL on success, false on failure.
 */
function wc_get_raw_referer()
{
    if (function_exists('wp_get_raw_referer')) {
        return wp_get_raw_referer();
    }
    if (!empty($_REQUEST['_wp_http_referer'])) {
        return wp_unslash($_REQUEST['_wp_http_referer']);
    } elseif (!empty($_SERVER['HTTP_REFERER'])) {
        return wp_unslash($_SERVER['HTTP_REFERER']);
    }
    return false;
}

/**
 * Retrieve referer from '_wp_http_referer' or HTTP referer.
 *
 * If it's the same as the current request URL, will return false.
 *
 * @since 2.0.4
 *
 * @return false|string False on failure. Referer URL on success.
 */
function wp_get_referer()
{
    if (!function_exists('wp_validate_redirect')) {
        return false;
    }
    $ref = wp_get_raw_referer();
    if ($ref && $ref !== wp_unslash($_SERVER['REQUEST_URI']) && $ref !== home_url() . wp_unslash($_SERVER['REQUEST_URI'])) {
        return wp_validate_redirect($ref, false);
    }
    return false;
}

 /**
  * @ticket 27152
  */
 public function test_raw_referer_both()
 {
     $_SERVER['HTTP_REFERER'] = addslashes('http://example.com/foo?bar');
     $_REQUEST['_wp_http_referer'] = addslashes('http://foo.bar/baz');
     $this->assertSame('http://foo.bar/baz', wp_get_raw_referer());
 }

 /**
  * Check if request is an create or enable/disable redirection
  */
 function on_admin_init()
 {
     $referer = wp_get_raw_referer();
     // We only continue if referer contains page=redirection.php
     if (false === strpos($referer, "page=redirection.php")) {
         return;
     }
     $referer_parsed = parse_url($referer);
     error_log("-----");
     // error_log( SimpleHistory::json_encode( $referer_parsed ) );
     error_log(SimpleHistory::json_encode($_REQUEST));
     /*
     Create redirection
     {
     	"source": "source yo",
     	"match": "url",
     	"red_action": "url",
     	"target": "dest yo",
     	"group_id": "1",
     	"add": "Add Redirection",
     	"group": "0",
     	"action": "red_redirect_add",
     	"_wpnonce": "cdadb5a4ca",
     	"_wp_http_referer": "\/wp-admin\/tools.php?page=redirection.php"
     }
     */
     if (isset($_REQUEST["action"]) && $_REQUEST["action"] == "red_redirect_add") {
         $this->log_redirection_add($_REQUEST);
         return;
     }
     /*
     Enable/disable single or multiple direction(s)
     {
     	"page": "redirection.php",
     	"_wpnonce": "290f261024",
     	"_wp_http_referer": "\/wp-admin\/tools.php?page=redirection.php",
     	"action": "enable", or "disable"
     	"id": "0",
     	"paged": "1",
     	"item": [
     		"3",
     		"2",
     		"1"
     	],
     	"action2": "-1"
     }
     */
     if (isset($_REQUEST["action"]) && $_REQUEST["action"] == "enable" && empty($_REQUEST["sub"])) {
         $this->log_redirection_enable_or_disable($_REQUEST);
         return;
     } else {
         if (isset($_REQUEST["action"]) && $_REQUEST["action"] == "disable" && empty($_REQUEST["sub"])) {
             $this->log_redirection_enable_or_disable($_REQUEST);
             return;
         }
     }
     /*
     Delete item(s)
     {
         "page": "redirection.php",
         "edit": "4",
         "_wpnonce": "290f261024",
         "_wp_http_referer": "\/wp-admin\/tools.php?page=redirection.php&edit=4",
         "action": "delete",
         "id": "0",
         "paged": "1",
         "item": [
             "6"
         ],
         "action2": "-1"
     }
     */
     if (isset($_REQUEST["action"]) && $_REQUEST["action"] == "delete" && empty($_REQUEST["sub"])) {
         $this->log_redirection_delete($_REQUEST);
         return;
     }
     /*
     Options
     - delete all options and deactivate plugin
     {
         "page": "redirection.php",
         "sub": "options",
         "_wpnonce": "e2c008ca25",
         "_wp_http_referer": "\/wp-admin\/tools.php?page=redirection.php&sub=options",
         "delete": "Delete"
     }
     */
     if (isset($_REQUEST["sub"]) && $_REQUEST["sub"] == "options" && isset($_REQUEST["delete"]) && $_REQUEST["delete"] == "Delete") {
         $this->log_options_delete_all($_REQUEST);
         return;
     }
     /*
     Save options {
         "page": "redirection.php",
         "sub": "options",
         "_wpnonce": "8fe9b57662",
         "_wp_http_referer": "\/wp-admin\/tools.php?page=redirection.php&sub=options",
//.........这里部分代码省略.........

/**
 * Since WP 4.5 em_wp_get_referer() returns false if URL is the same. We use it to get a safe referrer url, so we use the new wp_get_raw_referer() argument instead.
 * @since 5.6.3
 * @return string 
 */
function em_wp_get_referer()
{
    if (function_exists('wp_get_raw_referer')) {
        //do essentially what em_wp_get_referer does, but potentially returning the same url as before
        return wp_validate_redirect(wp_get_raw_referer(), false);
    } else {
        return wp_get_referer();
    }
}