Custom Prorating for PMPro with Delayed Downgrades

pmpro-custom-prorating.php

<?php
/*
Plugin Name: PMPro Custom Prorating Code
Plugin URI: http://www.paidmembershipspro.com/wp/pmpro-custom-prorating/
Description: Custom Prorating Code and Other Code for PMPro
Version: .2
Author: Stranger Studios
Author URI: http://www.strangerstudios.com
*/

/*
  Prorated payments. When a member chooses to upgrade, 
  he should be charged a pro-rated amount for the new membership level immediately, 
  and the payment date should stay the same.

  When downgrading, the initial payment is $0 and the downgrade is delayed until
  the next payment date.

  Downgrades are defined as having an initial payment $ less than the current level, but
  can be alterred via filters.

  Assumes initial payments are equal to billing amount.

  A limitation of this code is that if a member upgrades twice within one pay period,
  only the last payment will be considered with the prorating. This could be handled
  by summing the total of all orders within the pay period, but this could cause conflicts
  on sites that have multiple unrelated orders (pmpro addon packages or similar customizations)
  and payments on edge dates might be accidentally included or not included in the sum.
 
  Add this code to your active theme's functions.php or include this in a custom plugin.
  
  == Plans ==
  * Would like to find a way to handle cases where there are more than one upgrade/downgrade within one payment period.
  
  == Changelog ==
  
  = .2 =
  * Downgrade function updated to assume level order based on initial payments. Be sure to edit this to your needs.
  * Fixed issue where the existing subscription date was not being used.
  
*/

/*
	Function to check if a level change is a downgrade.	

	Assumes levels with smaller initial payments are
	downgrades. Change this if this is not the case on your
	site.
*/
function pmprorate_isDowngrade($old, $new)
{
	$old_level = pmpro_getLevel($old);
	$new_level = pmpro_getLevel($new);

	if($old_level->initial_payment > $new_level->initial_payment)
		$r = true;
	else
		$r = false;

	$r = apply_filters("pmpro_is_downgrade", $r, $old, $new);

	return $r;
}

/*
	Update the initial payment amount at checkout per prorating rules.
*/
function pmprorate_pmpro_checkout_level($level)
{
  	//does the user have a level already?
	if(pmpro_hasMembershipLevel())
	{
		//get current level
		global $current_user;
		$clevel = $current_user->membership_level;
		
		//downgrading?		
		if(pmprorate_isDowngrade($clevel->id, $level->id))
		{					
			//downgrade, just $0 initial payment
			$level->initial_payment = 0;
			
			//remember the old level for later
			global $pmpro_checkout_old_level;
			$pmpro_checkout_old_level = $clevel;
			
			//return now
			return $level;
		}

		//get their payment date
		$morder = new MemberOrder();
		$morder->getLastMemberOrder($current_user->ID, array('success', '', 'cancelled'));
		
		//no order?
		if(empty($morder->timestamp))
			return $level;
		
		$payment_date = strtotime(date("Y-m-d", $morder->timestamp));			
		$payment_day = intval(date("j", $morder->timestamp));
					
		//when would the next payment be			
		$next_payment_date = strtotime(date("Y-m-d", $payment_date) . " + " . $clevel->cycle_number . " " . $clevel->cycle_period);
				
		//today
		$today = current_time("timestamp");
				
		//how many days in this period
		$days_in_period = ceil(($next_payment_date - $payment_date)/3600/24);
		
		//if no days in period (next payment should have happened already) return level with no change to avoid divide by 0
		if($days_in_period <= 0)
			return $level;
						
		//how many days have passed		
		$days_passed = ceil(($today - $payment_date)/3600/24);
									
		//what percentage
		$per_passed = $days_passed / $days_in_period;		//as a % (decimal)
		$per_left = 1 - $per_passed;
		
		/*
			Now figure out how to adjust the price.
			(a) What they should pay for new level = $level->billing_amount * $per_left.
			(b) What they should have paid for current level = $clevel->billing_amount * $per_passed.
			What they need to pay = (a) + (b) - (what they already paid)
		*/
		$new_level_cost = $level->billing_amount * $per_left;
		$old_level_cost = $clevel->billing_amount * $per_passed;
		
		$level->initial_payment = min($level->initial_payment, round($new_level_cost + $old_level_cost - $morder->total, 2));
		
		//just in case we have a negative payment
		if($level->initial_payment < 0)
			$level->initial_payment = 0;								
	}
		
	return $level;
}
add_filter("pmpro_checkout_level", "pmprorate_pmpro_checkout_level");

/*
	Keep the same payment date.
*/
function pmprorate_pmpro_profile_start_date($startdate, $order)
{
	if(pmpro_hasMembershipLevel())
	{
		// Fetch the date of the most recent order for current user
		if(!empty($order->user_id))
			$last_recurring_order_datetime = pmprorate_pmpro_getLastRecurringOrderDatetime($order->user_id);
		else
			$last_recurring_order_datetime = pmprorate_pmpro_getLastRecurringOrderDatetime();
		
		if(!empty($last_recurring_order_datetime))
			$startdate = date("Y-m-d", strtotime(date("Y-m-d", $last_recurring_order_datetime) . " + " . $order->BillingFrequency . " " . $order->BillingPeriod)) . "T0:0:0";
	}

	return $startdate;
}
add_filter("pmpro_profile_start_date", "pmprorate_pmpro_profile_start_date", 10, 2);

/*
	Get the date of the last recurring order.
*/
function pmprorate_pmpro_getLastRecurringOrderDatetime($user_id = NULL)
{
	global $wpdb;

	// Fetch most recent order
	$lastorder = new MemberOrder();
	$lastorder->getLastMemberOrder($user_id);

	//no order? no current membership
	if(empty($lastorder))
		return false;

	//check gateways
	if($lastorder->gateway == "stripe")
	{
		//get subscription from Stripe API and look for current_period_start
		$gateway = new PMProGateway_stripe();
		$subscription = $gateway->getSubscription($lastorder);

		if(!empty($subscription) && !empty($subscription->current_period_start))
			return $subscription->current_period_start;
	}

	//check if this order is recurring and find the latest recurring order
	$check12 = 0;
	while(!pmprorate_pmpro_isOrderRecurring($lastorder) && $check12++ < 12)
	{
		$new_order_id = $wpdb->get_var("SELECT id FROM $wpdb->pmpro_membership_orders WHERE user_id = '" . $lastorder->user_id . "' AND status IN('', 'success') AND id < '" . $lastorder->id . "' ORDER BY timestamp DESC LIMIT 1");
		if(!empty($new_order_id))
			$lastorder = new MemberOrder($new_order_id);
		
		if(empty($lastorder) || empty($lastorder->id))
			return false;	//found no recurring orders for this member
	}

	//use latest recurring PMPro order to figure out next payment date
	if(!empty($lastorder) && !empty($lastorder->timestamp))
		return $lastorder->timestamp;

	return false;
}

function pmprorate_pmpro_isOrderRecurring( $order, $test_checkout = false ) {
	global $wpdb;
 
	//must have a subscription_transaction_id
	if( empty( $order->subscription_transaction_id ) ) {
		return false;
	}
 
	//check that we aren't processing at checkout
	if( $test_checkout && ! empty( $_REQUEST['submit-checkout'] ) )
		return false;
	
	//check for earlier orders with the same gateway, user_id, membership_id, and subscription_transaction_id
	$sqlQuery = "SELECT id FROM $wpdb->pmpro_membership_orders WHERE
								gateway = '" . esc_sql( $order->gateway ) . "' AND
								gateway_environment = '" . esc_sql( $order->gateway_environment ) . "' AND
								user_id = '" . esc_sql( $order->user_id) . "' AND
								membership_id = '" . esc_sql( $order->membership_id ) . "' AND
								subscription_transaction_id = '" . esc_sql( $order->subscription_transaction_id ) . "' AND
								timestamp < '" . date("Y-m-d", $order->timestamp) . "' ";
	if( ! empty( $order->id ) ) {
		$sqlQuery .= " AND id <> '" . esc_sql( $order->id ) . "' ";
	}
 
	$sqlQuery .= "LIMIT 1";
	$earlier_order = $wpdb->get_var( $sqlQuery );
		
	if ( empty( $earlier_order ) ) {
		return false;
	}
 
	//must be recurring
	return true;
}

/*
  Keep your old startdate.
  Updated from what's in paid-memberships-pro/includes/filters.php to run if the user has ANY level
*/
function pmprorate_pmpro_checkout_start_date_keep_startdate($startdate, $user_id, $level)
{				
	if(pmpro_hasMembershipLevel())  //<-- the line that was changed
	{
		global $wpdb;
		$sqlQuery = "SELECT startdate FROM $wpdb->pmpro_memberships_users WHERE user_id = '" . esc_sql($user_id) . "' AND status = 'active' ORDER BY id DESC LIMIT 1";		
		$old_startdate = $wpdb->get_var($sqlQuery);
		
		if(!empty($old_startdate))
			$startdate = "'" . $old_startdate . "'";		
	}
	
	return $startdate;
}

//add/remove hooks in init to make sure it runs after PMPro loads
function pmprorate_pmpro_init()
{
	remove_filter("pmpro_checkout_start_date", "pmpro_checkout_start_date_keep_startdate", 10, 3);	//remove the default PMPro filter
	add_filter("pmpro_checkout_start_date", "pmprorate_pmpro_checkout_start_date_keep_startdate", 10, 3);	//our filter works with ANY level
}
add_action('init', 'pmprorate_pmpro_init');

/*
	After checkout, if the user downgraded, then revert to the old level and remember to change them to the new level later.
*/
function pmprorate_pmpro_after_checkout($user_id)
{
	global $pmpro_checkout_old_level, $wpdb;
	if(!empty($pmpro_checkout_old_level) && !empty($pmpro_checkout_old_level->next_payment))
	{
		$new_level = pmpro_getMembershipLevelForUser($user_id);
		
		//remember to update to this level later
		update_user_meta($user_id, "pmpro_change_to_level", array("date"=>$pmpro_checkout_old_level->next_payment, "level"=>$new_level->id));
		
		//change their membership level
		$wpdb->query("UPDATE $wpdb->pmpro_memberships_users SET membership_id = '" . $pmpro_checkout_old_level->id . "' WHERE membership_id = '" . $new_level->id . "' AND user_id = '" . $user_id . "' AND status = 'active'");
	}
	else
		delete_user_meta($user_id, "pmpro_change_to_level");
}
add_filter('pmpro_after_checkout', 'pmprorate_pmpro_after_checkout');

/*
	Update confirmation message.
*/
function pmprorate_pmpro_confirmation_message($message, $invoice)
{	
	if(!empty($invoice) && !empty($invoice->user_id))
	{	
		$downgrading = get_user_meta($invoice->user_id, "pmpro_change_to_level", true);
			
		if(!empty($downgrading))
		{
			$dlevel = pmpro_getLevel($downgrading['level']);
		
			$message .= "<p>You will be downgraded to " . $dlevel->name . " on " . date(get_option("date_format"), strtotime($downgrading['date'], current_time('timestamp'))) . ".";
		}
	}
	
	return $message;
}
add_filter("pmpro_confirmation_message", "pmprorate_pmpro_confirmation_message", 10, 2);

/*
	Update account page.
*/
function pmprorate_the_content($content)
{
	global $current_user, $pmpro_pages;
		
	if(is_user_logged_in() && is_page($pmpro_pages['account']))
	{
		$downgrading = get_user_meta($current_user->ID, "pmpro_change_to_level", true);
				
		if(!empty($downgrading))
		{
			$downgrade_message = "<p><strong>Important Note:</strong> You will be downgraded to " . $downgrading['level']->name . " on " . date(get_option("date_format"), strtotime($downgrading['date'], current_time('timestamp'))) . ".";
			
			$content = $downgrade_message . $content;
		}
	}

	return $content;
}
add_filter("the_content", "pmprorate_the_content");

/*
	Check for level changes daily.
*/
function pmproproate_daily_check_for_membership_changes()
{
	global $wpdb;
	
	//make sure we only run once a day
	$today = date("Y-m-d", current_time('timestamp'));
		
	//get all users with scheduled level changes
	$level_changes = $wpdb->get_col("SELECT user_id FROM $wpdb->usermeta WHERE meta_key = 'pmpro_change_to_level'");
	
	if(empty($level_changes))
		return;
		
	foreach($level_changes as $user_id)
	{
		//today?
		$change = get_user_meta($user_id, 'pmpro_change_to_level', true);
				
		if(!empty($change) && !empty($change['date']) && !empty($change['level']) && $change['date'] <= $today)
		{
			//get user's current level
			$clevel = pmpro_getMembershipLevelForUser($user_id);
		
			//change back
			if(!empty($clevel))
				$wpdb->query("UPDATE $wpdb->pmpro_memberships_users SET membership_id = '" . $change['level'] . "' WHERE membership_id = '" . $clevel->id . "' AND user_id = '" . $user_id . "' AND status = 'active'");
				
			//delete user meta
			delete_user_meta($user_id, 'pmpro_change_to_level');
		}
	}
}
//hook to run when pmpro_cron_expire_memberships does
add_action('pmpro_cron_expire_memberships', 'pmproproate_daily_check_for_membership_changes');

is this still compatible with the actual versions of pmpro & wp? there is a way to add a section at the script to allow buying the same membership level as the user's actual one and treat it as renewal, prorating the difference in days as discount?