<?php
// @codingStandardsIgnoreFile
/**
 * s2Member's PayPal IPN handler (inner processing routines).
 *
 * Copyright: © 2009-2011
 * {@link http://websharks-inc.com/ WebSharks, Inc.}
 * (coded in the USA)
 *
 * Released under the terms of the GNU General Public License.
 * You should have received a copy of the GNU General Public License,
 * along with this software. In the main directory, see: /licensing/
 * If not, see: {@link http://www.gnu.org/licenses/}.
 *
 * @package s2Member\PayPal
 * @since 3.5
 */
if(!defined('WPINC')) // MUST have WordPress.
	exit ('Do not access this file directly.');

if(!class_exists('c_ws_plugin__s2member_paypal_notify_in'))
{
	/**
	 * s2Member's PayPal IPN handler (inner processing routines).
	 *
	 * @package s2Member\PayPal
	 * @since 3.5
	 */
	class c_ws_plugin__s2member_paypal_notify_in
	{
		//260907.2110 TO-DO: Before final PayPal Standard deprecation, review IPN/return replay protection against the shared fulfillment/dedupe invariants; provider-hosted button creation itself does not need Gateway Checkout creation orchestration.
		/**
		 * Handles PayPal IPN processing.
		 *
		 * These same routines also handle s2Member Pro/PayPal Pro operations;
		 * giving you the ability *(as needed)* to Hook into these routines using
		 * WordPress Hooks/Filters; as seen in the source code below.
		 *
		 * Please do NOT modify the source code directly.
		 * Instead, use WordPress Hooks/Filters.
		 *
		 * For example, if you'd like to add your own custom conditionals, use:
		 * ``add_filter ('ws_plugin__s2member_during_paypal_notify_conditionals', 'your_function');``
		 *
		 * @package s2Member\PayPal
		 * @since 3.5
		 *
		 * @attaches-to ``add_action('init');``
		 */
		public static function paypal_notify()
		{
			global $current_site, $current_blog;

			do_action('ws_plugin__s2member_before_paypal_notify', get_defined_vars());

			//260831.0135 Normalize optional s2Member proxy fields once; direct PayPal IPNs omit them, while proxied gateway integrations provide strings.
			if(!isset($_REQUEST['s2member_paypal_proxy']) || !is_string($_REQUEST['s2member_paypal_proxy']))
				$_REQUEST['s2member_paypal_proxy'] = '';
			if(!isset($_REQUEST['s2member_paypal_proxy_use']) || !is_string($_REQUEST['s2member_paypal_proxy_use']))
				$_REQUEST['s2member_paypal_proxy_use'] = '';

			if(!empty($_GET['s2member_paypal_notify']) && ($GLOBALS['WS_PLUGIN__']['s2member']['o']['paypal_business'] || !empty($_REQUEST['s2member_paypal_proxy'])))
			{
				@ignore_user_abort(TRUE); // Important. Continue processing even if/when the connection is broken by the sending party.

				include_once ABSPATH.'wp-admin/includes/admin.php'; // Get administrative functions. Needed for `wp_delete_user()`.

				$email_configs_were_on = c_ws_plugin__s2member_email_configs::email_config_status(); // Filters on?
				c_ws_plugin__s2member_email_configs::email_config_release(); // Release s2Member Filters.

				$paypal = array(); // Initialize PayPal array; we also reference this with a variable for a possible proxy handler.
				if(!empty($_REQUEST['s2member_paypal_proxy']) && in_array($_REQUEST['s2member_paypal_proxy'], array('alipay', 'stripe', 'authnet', 'clickbank', 'ccbill', 'google'), TRUE))
					${esc_html(trim(stripslashes($_REQUEST['s2member_paypal_proxy'])))} = & $paypal; // Internal alias by reference.

				if(is_array($paypal = c_ws_plugin__s2member_paypal_utilities::paypal_postvars()) && ($_paypal = $paypal) && ($_paypal_s = serialize($_paypal)))
				{
					$paypal['s2member_log'][] = 'IPN received on: '.date('D M j, Y g:i:s a T');
					$paypal['s2member_log'][] = 's2Member POST vars verified '.((!empty($paypal['proxy_verified'])) ? 'with a Proxy Key' : 'through a POST back to PayPal.');

					$payment_status_issues = '/^(failed|denied|expired|refunded|partially_refunded|reversed|reversal|canceled_reversal|voided)$/i';

					$paypal['subscr_gateway'] = (!empty($_REQUEST['s2member_paypal_proxy'])) ? esc_html(trim(stripslashes($_REQUEST['s2member_paypal_proxy']))) : 'paypal';

					$coupon = (!empty($_REQUEST['s2member_paypal_proxy_coupon']) && is_array($_REQUEST['s2member_paypal_proxy_coupon'])) ? stripslashes_deep($_REQUEST['s2member_paypal_proxy_coupon']) : array();
					$coupon = (isset($coupon['full_coupon_code'], $coupon['coupon_code'], $coupon['affiliate_id']) && is_string($coupon['full_coupon_code']) && is_string($coupon['coupon_code']) && is_string($coupon['affiliate_id'])) ? $coupon : array('full_coupon_code' => '', 'coupon_code' => '', 'affiliate_id' => '');
					$coupon = c_ws_plugin__s2member_utils_strings::strip_php_tags_deep($coupon); //260910.2249 Normalize proxy coupon data consistently with other notification values.

					if(!empty($paypal['txn_type']) && $paypal['txn_type'] === 'merch_pmt')
						// This is mostly irrelevant, but it helps to keep the logs cleaner.
						sleep(15); // Wait for Pro-Form procesing to complete.

					if(empty($paypal['custom']) && !empty($paypal['recurring_payment_id'])) // Recurring Profile ID.
						$paypal['custom'] = c_ws_plugin__s2member_utils_users::get_user_custom_with($paypal['recurring_payment_id']);

					else if(empty($paypal['custom']) && !empty($paypal['mp_id'])) // Billing Agreement ID.
						$paypal['custom'] = c_ws_plugin__s2member_utils_users::get_user_custom_with($paypal['mp_id']);

					//250522 At least set it to an empty string.
					else if(empty($paypal['custom']))
						$paypal['custom'] = '';
					
					//260910.0356 Resolve the expected host consistently across different web-server request environments.
					$ipn_host = (!empty($_SERVER['HTTP_HOST']) && is_string($_SERVER['HTTP_HOST'])) ? preg_replace('/\:([0-9]+)$/', '', $_SERVER['HTTP_HOST']) : (string)parse_url(home_url('/'), PHP_URL_HOST);

					//250606 Added option to skip domain validation.
					if ($GLOBALS['WS_PLUGIN__']['s2member']['o']['skip_ipn_domain_validation']
					|| ($ipn_host !== '' && !empty($paypal['custom']) && preg_match('/^'.preg_quote($ipn_host, '/').'/i', $paypal['custom'])))
					{
						if ($GLOBALS['WS_PLUGIN__']['s2member']['o']['skip_ipn_domain_validation']) 
							$paypal['s2member_log'][] = 's2Member originating domain validation was skipped.';
						else
							$paypal['s2member_log'][] = 's2Member originating domain (`$_SERVER["HTTP_HOST"]`) validated.';

						foreach(array_keys(get_defined_vars()) as $__v) $__refs[$__v] =& $$__v;
						if(!apply_filters('ws_plugin__s2member_during_paypal_notify_conditionals', FALSE, get_defined_vars()))
						{
							unset($__refs, $__v); // From the filter above.

							if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_virtual_terminal::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_express_checkout::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_cart::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_send_money::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_web_accept_sp::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_wa_ccaps_wo_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_subscr_or_wa_w_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_rec_profile_creation_w_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_subscr_modify_w_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_subscr_or_rp_payment_w_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_subscr_or_rp_payment_failed_w_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_subscr_or_rp_cancellation_w_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_subscr_or_rp_eots_w_level::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_sp_refund_reversal::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else if(($_paypal_cp = c_ws_plugin__s2member_paypal_notify_in_billing_agreement_signup::cp(get_defined_vars())))
								$paypal = $_paypal_cp;

							else // Ignoring this IPN request. The txn_type/status does NOT require any action.
								$paypal['s2member_log'][] = 'Ignoring this IPN request. The `txn_type/status` does NOT require any action on the part of s2Member.';
						}
						else unset($__refs, $__v); // Else a custom conditional has been applied by Filters.
					}
					else if(!empty($paypal['txn_type']) && preg_match('/^recurring_payment_profile_cancel$/i', $paypal['txn_type']))
					{
						$paypal['s2member_log'][] = 'Transaction type (`recurring_payment_profile_cancel`), but there is no match to an existing account; so verification of `$_SERVER["HTTP_HOST"]` was not possible.';
						$paypal['s2member_log'][] = 'It\'s likely this account was just upgraded/downgraded by s2Member Pro; so the Subscr. ID has probably been updated on-site; nothing to worry about here.';
					}
					else if(!empty($paypal['txn_type']) && preg_match('/^recurring_/i', $paypal['txn_type'])) // Otherwise, is this a ^recurring_ txn_type?
						$paypal['s2member_log'][] = 'Transaction type (`^recurring_?`), but there is no match to an existing account; so verification of `$_SERVER["HTTP_HOST"]` was not possible.';

					else // Else, use the default ``$_SERVER['HTTP_HOST']`` error.
						$paypal['s2member_log'][] = 'Unable to verify `$_SERVER["HTTP_HOST"]`. Please check the `custom` value in your Button Code. It MUST start with your domain name.';
				}
				else // Extensive log reporting here. This is an area where many site owners find trouble. Depending on server configuration; remote HTTPS connections may fail.
				{
					if (!empty($_SERVER['REQUEST_METHOD']) && $_SERVER['REQUEST_METHOD'] === 'GET' && !empty($_SERVER['HTTP_USER_AGENT'])) {
						if (preg_match('/(msie|trident|gecko|webkit|presto|konqueror|playstation)[\/ ]([0-9\.]+)/i', $_SERVER['HTTP_USER_AGENT'])) {
							$paypal['s2member_indicator'] = 'This PayPal IPN Handler by s2Member® is active & listening.';
						}
					}
					$paypal['s2member_log'][] = 'Unable to verify $_POST vars. This is most likely related to an invalid configuration of s2Member, or a problem with server compatibility.';
					$paypal['s2member_log'][] = 'Please see this KB article: `http://www.s2member.com/kb/server-scanner/`. We suggest that you run the s2Member Server Scanner.';
					$paypal['s2member_log'][] = var_export($_REQUEST, TRUE); // Recording _POST + _GET vars for analysis and debugging.
				}
				if($email_configs_were_on) // Back on?
					c_ws_plugin__s2member_email_configs::email_config();
				/*
				Add IPN proxy (when available) to the ``$paypal`` array.
				*/
				if(!empty($_REQUEST['s2member_paypal_proxy']))
					$paypal['s2member_paypal_proxy'] = esc_html(trim(stripslashes((string)$_REQUEST['s2member_paypal_proxy'])));
				/*
				Add IPN proxy use vars (when available) to the ``$paypal`` array.
				*/
				if(!empty($_REQUEST['s2member_paypal_proxy_use']))
					$paypal['s2member_paypal_proxy_use'] = esc_html(trim(stripslashes((string)$_REQUEST['s2member_paypal_proxy_use'])));
				/*
				Add IPN proxy coupon vars (when available) to the ``$paypal`` array.
				*/
				if(!empty($_REQUEST['s2member_paypal_proxy_coupon']))
					$paypal['s2member_paypal_proxy_coupon'] = stripslashes_deep((array)$_REQUEST['s2member_paypal_proxy_coupon']);
				/*
				Also add IPN proxy self-verification (when available) to the ``$paypal`` array.
				*/
				if(!empty($_REQUEST['s2member_paypal_proxy_verification']))
					$paypal['s2member_paypal_proxy_verification'] = esc_html(trim(stripslashes((string)$_REQUEST['s2member_paypal_proxy_verification'])));
				/*
				Log this IPN post-processing event now.
				*/
				c_ws_plugin__s2member_utils_logs::log_entry('gateway-core-ipn', $paypal);
				/*
				Hook during core IPN post-processing might be useful for developers.
				*/
				foreach(array_keys(get_defined_vars()) as $__v) $__refs[$__v] =& $$__v;
				do_action('ws_plugin__s2member_during_paypal_notify', get_defined_vars());
				unset($__refs, $__v);
				/*
				260322 Log effective response state before/after forcing a 200.
				Output response headers & content body.
				*/
				$paypal['s2member_log'][] = 'Pre-response `headers_sent`: '.((headers_sent($headers_sent_file, $headers_sent_line)) ? 'yes @ '.$headers_sent_file.':'.$headers_sent_line : 'no');
				$paypal['s2member_log'][] = 'Pre-response `http_response_code()`: '.((function_exists('http_response_code')) ? (string)http_response_code() : 'n/a');
				$paypal['s2member_log'][] = 'Pre-response headers: '.var_export(headers_list(), TRUE);

				while(@ob_end_clean()); // Clean output buffers.

				if(function_exists('http_response_code'))
					http_response_code(200);

				if(!empty($_SERVER['SERVER_PROTOCOL']))
					header($_SERVER['SERVER_PROTOCOL'].' 200 OK', TRUE, 200);
				else
					header('HTTP/1.1 200 OK', TRUE, 200);

				status_header(200); // OK status code.
				header('Content-Type: text/plain; charset=UTF-8');

				$paypal['s2member_log'][] = 'Post-response `http_response_code()`: '.((function_exists('http_response_code')) ? (string)http_response_code() : 'n/a');
				$paypal['s2member_log'][] = 'Post-response headers: '.var_export(headers_list(), TRUE);

				if (!empty($paypal['s2member_paypal_proxy_return_url'])) {
					if(preg_match('/^https?%3A/ui', $paypal['s2member_paypal_proxy_return_url'])) {
						$paypal['s2member_paypal_proxy_return_url'] = urldecode($paypal['s2member_paypal_proxy_return_url']);
					} // See: <https://github.com/websharks/s2member/issues/1024>
					exit($paypal['s2member_paypal_proxy_return_url']);
				} elseif (!empty($paypal['s2member_indicator'])) {
					exit($paypal['s2member_indicator']);
				} else {
					exit(); // Default behavior.
				}
			}
			foreach(array_keys(get_defined_vars()) as $__v) $__refs[$__v] =& $$__v;
			do_action('ws_plugin__s2member_after_paypal_notify', get_defined_vars());
			unset($__refs, $__v);
		}
	}
}