<?php

use EventEspresso\core\exceptions\InvalidDataTypeException;
use EventEspresso\core\exceptions\InvalidInterfaceException;

/**
 * EE_Transaction class
 *
 * @package       Event Espresso
 * @subpackage    includes/classes/EE_Transaction.class.php
 * @author        Brent Christensen
 */
class EE_Transaction extends EE_Base_Class implements EEI_Transaction
{

    /**
     * The length of time in seconds that a lock is applied before being considered expired.
     * It is not long because a transaction should only be locked for the duration of the request that locked it
     */
    const LOCK_EXPIRATION = 2;

    /**
     * txn status upon initial construction.
     *
     * @var string
     */
    protected $_old_txn_status;


    /**
     * @param array  $props_n_values          incoming values
     * @param string $timezone                incoming timezone
     *                                        (if not set the timezone set for the website will be used.)
     * @param array  $date_formats            incoming date_formats in an array where the first value is the
     *                                        date_format and the second value is the time format
     * @return EE_Transaction
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public static function new_instance($props_n_values = array(), $timezone = null, $date_formats = array())
    {
        $has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
        $txn = $has_object
            ? $has_object
            : new self($props_n_values, false, $timezone, $date_formats);
        if (! $has_object) {
            $txn->set_old_txn_status($txn->status_ID());
        }
        return $txn;
    }


    /**
     * @param array  $props_n_values  incoming values from the database
     * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
     *                                the website will be used.
     * @return EE_Transaction
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public static function new_instance_from_db($props_n_values = array(), $timezone = null)
    {
        $txn = new self($props_n_values, true, $timezone);
        $txn->set_old_txn_status($txn->status_ID());
        return $txn;
    }


    /**
     * Sets a meta field indicating that this TXN is locked and should not be updated in the db.
     * If a lock has already been set, then we will attempt to remove it in case it has expired.
     * If that also fails, then an exception is thrown.
     *
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function lock()
    {
        // attempt to set lock, but if that fails...
        if (! $this->add_extra_meta('lock', time(), true)) {
            // then attempt to remove the lock in case it is expired
            if ($this->_remove_expired_lock()) {
                // if removal was successful, then try setting lock again
                $this->lock();
            } else {
                // but if the lock can not be removed, then throw an exception
                throw new EE_Error(
                    sprintf(
                        __(
                            'Could not lock Transaction %1$d because it is already locked, meaning another part of the system is currently editing it. It should already be unlocked by the time you read this, so please refresh the page and try again.',
                            'event_espresso'
                        ),
                        $this->ID()
                    )
                );
            }
        }
    }


    /**
     * removes transaction lock applied in EE_Transaction::lock()
     *
     * @return int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function unlock()
    {
        return $this->delete_extra_meta('lock');
    }


    /**
     * Decides whether or not now is the right time to update the transaction.
     * This is useful because we don't always know if it is safe to update the transaction
     * and its related data. why?
     * because it's possible that the transaction is being used in another
     * request and could overwrite anything we save.
     * So we want to only update the txn once we know that won't happen.
     * We also check that the lock isn't expired, and remove it if it is
     *
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function is_locked()
    {
        // if TXN is not locked, then return false immediately
        if (! $this->_get_lock()) {
            return false;
        }
        // if not, then let's try and remove the lock in case it's expired...
        // _remove_expired_lock() returns 0 when lock is valid (ie: removed = false)
        // and a positive number if the lock was removed (ie: number of locks deleted),
        // so we need to return the opposite
        return ! $this->_remove_expired_lock() ? true : false;
    }


    /**
     * Gets the meta field indicating that this TXN is locked
     *
     * @return int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    protected function _get_lock()
    {
        return (int) $this->get_extra_meta('lock', true, 0);
    }


    /**
     * If the lock on this transaction is expired, then we want to remove it so that the transaction can be updated
     *
     * @return int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    protected function _remove_expired_lock()
    {
        $locked = $this->_get_lock();
        if ($locked && time() - EE_Transaction::LOCK_EXPIRATION > $locked) {
            return $this->unlock();
        }
        return 0;
    }


    /**
     * Set transaction total
     *
     * @param float $total total value of transaction
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_total($total = 0.00)
    {
        $this->set('TXN_total', (float) $total);
    }


    /**
     * Set Total Amount Paid to Date
     *
     * @param float $total_paid total amount paid to date (sum of all payments)
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_paid($total_paid = 0.00)
    {
        $this->set('TXN_paid', (float) $total_paid);
    }


    /**
     * Set transaction status
     *
     * @param string $status        whether the transaction is open, declined, accepted,
     *                              or any number of custom values that can be set
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_status($status = '')
    {
        $this->set('STS_ID', $status);
    }


    /**
     * Set hash salt
     *
     * @param string $hash_salt required for some payment gateways
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_hash_salt($hash_salt = '')
    {
        $this->set('TXN_hash_salt', $hash_salt);
    }


    /**
     * Sets TXN_reg_steps array
     *
     * @param array $txn_reg_steps
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_reg_steps(array $txn_reg_steps)
    {
        $this->set('TXN_reg_steps', $txn_reg_steps);
    }


    /**
     * Gets TXN_reg_steps
     *
     * @return array
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function reg_steps()
    {
        $TXN_reg_steps = $this->get('TXN_reg_steps');
        return is_array($TXN_reg_steps) ? (array) $TXN_reg_steps : array();
    }


    /**
     * @return string of transaction's total cost, with currency symbol and decimal
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function pretty_total()
    {
        return $this->get_pretty('TXN_total');
    }


    /**
     * Gets the amount paid in a pretty string (formatted and with currency symbol)
     *
     * @return string
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function pretty_paid()
    {
        return $this->get_pretty('TXN_paid');
    }


    /**
     * calculate the amount remaining for this transaction and return;
     *
     * @return float amount remaining
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function remaining()
    {
        return $this->total() - $this->paid();
    }


    /**
     * get Transaction Total
     *
     * @return float
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function total()
    {
        return (float) $this->get('TXN_total');
    }


    /**
     * get Total Amount Paid to Date
     *
     * @return float
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function paid()
    {
        return (float) $this->get('TXN_paid');
    }


    /**
     * @return mixed|null
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function get_cart_session()
    {
        $session_data = (array) $this->get('TXN_session_data');
        return isset($session_data['cart']) && $session_data['cart'] instanceof EE_Cart
            ? $session_data['cart']
            : null;
    }


    /**
     * get Transaction session data
     *
     * @return array|mixed
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function session_data()
    {
        $session_data = $this->get('TXN_session_data');
        if (empty($session_data)) {
            $session_data = array(
                'id'            => null,
                'user_id'       => null,
                'ip_address'    => null,
                'user_agent'    => null,
                'init_access'   => null,
                'last_access'   => null,
                'pages_visited' => array(),
            );
        }
        return $session_data;
    }


    /**
     * Set session data within the TXN object
     *
     * @param EE_Session|array $session_data
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_txn_session_data($session_data)
    {
        if ($session_data instanceof EE_Session) {
            $this->set('TXN_session_data', $session_data->get_session_data(null, true));
        } else {
            $this->set('TXN_session_data', $session_data);
        }
    }


    /**
     * get Transaction hash salt
     *
     * @return mixed
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function hash_salt_()
    {
        return $this->get('TXN_hash_salt');
    }


    /**
     * Returns the transaction datetime as either:
     *            - unix timestamp format ($format = false, $gmt = true)
     *            - formatted date string including the UTC (timezone) offset ($format = true ($gmt
     *              has no affect with this option)), this also may include a timezone abbreviation if the
     *              set timezone in this class differs from what the timezone is on the blog.
     *            - formatted date string including the UTC (timezone) offset (default).
     *
     * @param boolean $format   - whether to return a unix timestamp (default) or formatted date string
     * @param boolean $gmt      - whether to return a unix timestamp with UTC offset applied (default)
     *                          or no UTC offset applied
     * @return string | int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function datetime($format = false, $gmt = false)
    {
        if ($format) {
            return $this->get_pretty('TXN_timestamp');
        }
        if ($gmt) {
            return $this->get_raw('TXN_timestamp');
        }
        return $this->get('TXN_timestamp');
    }


    /**
     * Gets registrations on this transaction
     *
     * @param array   $query_params array of query parameters
     * @param boolean $get_cached   TRUE to retrieve cached registrations or FALSE to pull from the db
     * @return EE_Base_Class[]|EE_Registration[]
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function registrations($query_params = array(), $get_cached = false)
    {
        $query_params = (empty($query_params) || ! is_array($query_params))
            ? array(
                'order_by' => array(
                    'Event.EVT_name'     => 'ASC',
                    'Attendee.ATT_lname' => 'ASC',
                    'Attendee.ATT_fname' => 'ASC',
                ),
            )
            : $query_params;
        $query_params = $get_cached ? array() : $query_params;
        return $this->get_many_related('Registration', $query_params);
    }


    /**
     * Gets all the attendees for this transaction (handy for use with EE_Attendee's get_registrations_for_event
     * function for getting attendees and how many registrations they each have for an event)
     *
     * @return mixed EE_Attendee[] by default, int if $output is set to 'COUNT'
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function attendees()
    {
        return $this->get_many_related('Attendee', array(array('Registration.Transaction.TXN_ID' => $this->ID())));
    }


    /**
     * Gets payments for this transaction. Unlike other such functions, order by 'DESC' by default
     *
     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
     * @return EE_Base_Class[]|EE_Payment[]
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function payments($query_params = array())
    {
        return $this->get_many_related('Payment', $query_params);
    }


    /**
     * gets only approved payments for this transaction
     *
     * @return EE_Base_Class[]|EE_Payment[]
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws ReflectionException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     */
    public function approved_payments()
    {
        EE_Registry::instance()->load_model('Payment');
        return $this->get_many_related(
            'Payment',
            array(
                array('STS_ID' => EEM_Payment::status_id_approved),
                'order_by' => array('PAY_timestamp' => 'DESC'),
            )
        );
    }


    /**
     * Gets all payments which have not been approved
     *
     * @return EE_Base_Class[]|EEI_Payment[]
     * @throws EE_Error if a model is misconfigured somehow
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function pending_payments()
    {
        return $this->get_many_related(
            'Payment',
            array(
                array(
                    'STS_ID' => EEM_Payment::status_id_pending,
                ),
                'order_by' => array(
                    'PAY_timestamp' => 'DESC',
                ),
            )
        );
    }


    /**
     * echoes $this->pretty_status()
     *
     * @param bool $show_icons
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function e_pretty_status($show_icons = false)
    {
        echo $this->pretty_status($show_icons);
    }


    /**
     * returns a pretty version of the status, good for displaying to users
     *
     * @param bool $show_icons
     * @return string
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function pretty_status($show_icons = false)
    {
        $status = EEM_Status::instance()->localized_status(
            array($this->status_ID() => __('unknown', 'event_espresso')),
            false,
            'sentence'
        );
        $icon = '';
        switch ($this->status_ID()) {
            case EEM_Transaction::complete_status_code:
                $icon = $show_icons ? '<span class="dashicons dashicons-yes ee-icon-size-24 green-text"></span>' : '';
                break;
            case EEM_Transaction::incomplete_status_code:
                $icon = $show_icons ? '<span class="dashicons dashicons-marker ee-icon-size-16 lt-blue-text"></span>'
                    : '';
                break;
            case EEM_Transaction::abandoned_status_code:
                $icon = $show_icons ? '<span class="dashicons dashicons-marker ee-icon-size-16 red-text"></span>' : '';
                break;
            case EEM_Transaction::failed_status_code:
                $icon = $show_icons ? '<span class="dashicons dashicons-no ee-icon-size-16 red-text"></span>' : '';
                break;
            case EEM_Transaction::overpaid_status_code:
                $icon = $show_icons ? '<span class="dashicons dashicons-plus ee-icon-size-16 orange-text"></span>' : '';
                break;
        }
        return $icon . $status[ $this->status_ID() ];
    }


    /**
     * get Transaction Status
     *
     * @return mixed
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function status_ID()
    {
        return $this->get('STS_ID');
    }


    /**
     * Returns TRUE or FALSE for whether or not this transaction cost any money
     *
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function is_free()
    {
        return EEH_Money::compare_floats($this->get('TXN_total'), 0, '==');
    }


    /**
     * Returns whether this transaction is complete
     * Useful in templates and other logic for deciding if we should ask for another payment...
     *
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function is_completed()
    {
        return $this->status_ID() === EEM_Transaction::complete_status_code;
    }


    /**
     * Returns whether this transaction is incomplete
     * Useful in templates and other logic for deciding if we should ask for another payment...
     *
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function is_incomplete()
    {
        return $this->status_ID() === EEM_Transaction::incomplete_status_code;
    }


    /**
     * Returns whether this transaction is overpaid
     * Useful in templates and other logic for deciding if monies need to be refunded
     *
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function is_overpaid()
    {
        return $this->status_ID() === EEM_Transaction::overpaid_status_code;
    }


    /**
     * Returns whether this transaction was abandoned
     * meaning that the transaction/registration process was somehow interrupted and never completed
     * but that contact information exists for at least one registrant
     *
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function is_abandoned()
    {
        return $this->status_ID() === EEM_Transaction::abandoned_status_code;
    }


    /**
     * Returns whether this transaction failed
     * meaning that the transaction/registration process was somehow interrupted and never completed
     * and that NO contact information exists for any registrants
     *
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function failed()
    {
        return $this->status_ID() === EEM_Transaction::failed_status_code;
    }


    /**
     * This returns the url for the invoice of this transaction
     *
     * @param string $type 'html' or 'pdf' (default is pdf)
     * @return string
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function invoice_url($type = 'html')
    {
        $REG = $this->primary_registration();
        if (! $REG instanceof EE_Registration) {
            return '';
        }
        return $REG->invoice_url($type);
    }


    /**
     * Gets the primary registration only
     *
     * @return EE_Base_Class|EE_Registration
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function primary_registration()
    {
        $registrations = (array) $this->get_many_related(
            'Registration',
            array(array('REG_count' => EEM_Registration::PRIMARY_REGISTRANT_COUNT))
        );
        foreach ($registrations as $registration) {
            // valid registration that is NOT cancelled or declined ?
            if ($registration instanceof EE_Registration
                && ! in_array($registration->status_ID(), EEM_Registration::closed_reg_statuses(), true)
            ) {
                return $registration;
            }
        }
        // nothing valid found, so just return first thing from array of results
        return reset($registrations);
    }


    /**
     * Gets the URL for viewing the receipt
     *
     * @param string $type 'pdf' or 'html' (default is 'html')
     * @return string
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function receipt_url($type = 'html')
    {
        $REG = $this->primary_registration();
        if (! $REG instanceof EE_Registration) {
            return '';
        }
        return $REG->receipt_url($type);
    }


    /**
     * Gets the URL of the thank you page with this registration REG_url_link added as
     * a query parameter
     *
     * @return string
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function payment_overview_url()
    {
        $primary_registration = $this->primary_registration();
        return $primary_registration instanceof EE_Registration ? $primary_registration->payment_overview_url() : false;
    }


    /**
     * @return string
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function gateway_response_on_transaction()
    {
        $payment = $this->get_first_related('Payment');
        return $payment instanceof EE_Payment ? $payment->gateway_response() : '';
    }


    /**
     * Get the status object of this object
     *
     * @return EE_Base_Class|EE_Status
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function status_obj()
    {
        return $this->get_first_related('Status');
    }


    /**
     * Gets all the extra meta info on this payment
     *
     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
     * @return EE_Base_Class[]|EE_Extra_Meta
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function extra_meta($query_params = array())
    {
        return $this->get_many_related('Extra_Meta', $query_params);
    }


    /**
     * Wrapper for _add_relation_to
     *
     * @param EE_Registration $registration
     * @return EE_Base_Class the relation was added to
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function add_registration(EE_Registration $registration)
    {
        return $this->_add_relation_to($registration, 'Registration');
    }


    /**
     * Removes the given registration from being related (even before saving this transaction).
     * If an ID/index is provided and this transaction isn't saved yet, removes it from list of cached relations
     *
     * @param int $registration_or_id
     * @return EE_Base_Class that was removed from being related
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function remove_registration_with_id($registration_or_id)
    {
        return $this->_remove_relation_to($registration_or_id, 'Registration');
    }


    /**
     * Gets all the line items which are for ACTUAL items
     *
     * @return EE_Line_Item[]
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function items_purchased()
    {
        return $this->line_items(array(array('LIN_type' => EEM_Line_Item::type_line_item)));
    }


    /**
     * Wrapper for _add_relation_to
     *
     * @param EE_Line_Item $line_item
     * @return EE_Base_Class the relation was added to
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function add_line_item(EE_Line_Item $line_item)
    {
        return $this->_add_relation_to($line_item, 'Line_Item');
    }


    /**
     * Gets ALL the line items related to this transaction (unstructured)
     *
     * @param array $query_params
     * @return EE_Base_Class[]|EE_Line_Item[]
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function line_items($query_params = array())
    {
        return $this->get_many_related('Line_Item', $query_params);
    }


    /**
     * Gets all the line items which are taxes on the total
     *
     * @return EE_Line_Item[]
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function tax_items()
    {
        return $this->line_items(array(array('LIN_type' => EEM_Line_Item::type_tax)));
    }


    /**
     * Gets the total line item (which is a parent of all other related line items,
     * meaning it takes them all into account on its total)
     *
     * @param bool $create_if_not_found
     * @return \EE_Line_Item
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function total_line_item($create_if_not_found = true)
    {
        $item = $this->get_first_related('Line_Item', array(array('LIN_type' => EEM_Line_Item::type_total)));
        if (! $item && $create_if_not_found) {
            $item = EEH_Line_Item::create_total_line_item($this);
        }
        return $item;
    }


    /**
     * Returns the total amount of tax on this transaction
     * (assumes there's only one tax subtotal line item)
     *
     * @return float
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function tax_total()
    {
        $tax_line_item = $this->tax_total_line_item();
        if ($tax_line_item) {
            return (float) $tax_line_item->total();
        }
        return (float) 0;
    }


    /**
     * Gets the tax subtotal line item (assumes there's only one)
     *
     * @return EE_Line_Item
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function tax_total_line_item()
    {
        return EEH_Line_Item::get_taxes_subtotal($this->total_line_item());
    }


    /**
     * Gets the array of billing info for the gateway and for this transaction's primary registration's attendee.
     *
     * @return EE_Form_Section_Proper
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function billing_info()
    {
        $payment_method = $this->payment_method();
        if (! $payment_method) {
            EE_Error::add_error(
                __(
                    'Could not find billing info for transaction because no gateway has been used for it yet',
                    'event_espresso'
                ),
                __FILE__,
                __FUNCTION__,
                __LINE__
            );
            return null;
        }
        $primary_reg = $this->primary_registration();
        if (! $primary_reg) {
            EE_Error::add_error(
                __(
                    'Cannot get billing info for gateway %s on transaction because no primary registration exists',
                    'event_espresso'
                ),
                __FILE__,
                __FUNCTION__,
                __LINE__
            );
            return null;
        }
        $attendee = $primary_reg->attendee();
        if (! $attendee) {
            EE_Error::add_error(
                __(
                    'Cannot get billing info for gateway %s on transaction because the primary registration has no attendee exists',
                    'event_espresso'
                ),
                __FILE__,
                __FUNCTION__,
                __LINE__
            );
            return null;
        }
        return $attendee->billing_info_for_payment_method($payment_method);
    }


    /**
     * Gets PMD_ID
     *
     * @return int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function payment_method_ID()
    {
        return $this->get('PMD_ID');
    }


    /**
     * Sets PMD_ID
     *
     * @param int $PMD_ID
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_payment_method_ID($PMD_ID)
    {
        $this->set('PMD_ID', $PMD_ID);
    }


    /**
     * Gets the last-used payment method on this transaction
     * (we COULD just use the last-made payment, but some payment methods, namely
     * offline ones, dont' create payments)
     *
     * @return EE_Payment_Method
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function payment_method()
    {
        $pm = $this->get_first_related('Payment_Method');
        if ($pm instanceof EE_Payment_Method) {
            return $pm;
        }
        $last_payment = $this->last_payment();
        if ($last_payment instanceof EE_Payment && $last_payment->payment_method()) {
            return $last_payment->payment_method();
        }
        return null;
    }


    /**
     * Gets the last payment made
     *
     * @return EE_Base_Class|EE_Payment
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function last_payment()
    {
        return $this->get_first_related('Payment', array('order_by' => array('PAY_ID' => 'desc')));
    }


    /**
     * Gets all the line items which are unrelated to tickets on this transaction
     *
     * @return EE_Line_Item[]
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function non_ticket_line_items()
    {
        return EEM_Line_Item::instance()->get_all_non_ticket_line_items_for_transaction($this->ID());
    }


    /**
     * possibly toggles TXN status
     *
     * @param  boolean $update whether to save the TXN
     * @return bool whether the TXN was saved
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     * @throws RuntimeException
     */
    public function update_status_based_on_total_paid($update = true)
    {
        // set transaction status based on comparison of TXN_paid vs TXN_total
        if (EEH_Money::compare_floats($this->paid(), $this->total(), '>')) {
            $new_txn_status = EEM_Transaction::overpaid_status_code;
        } elseif (EEH_Money::compare_floats($this->paid(), $this->total())) {
            $new_txn_status = EEM_Transaction::complete_status_code;
        } elseif (EEH_Money::compare_floats($this->paid(), $this->total(), '<')) {
            $new_txn_status = EEM_Transaction::incomplete_status_code;
        } else {
            throw new RuntimeException(
                __('The total paid calculation for this transaction is inaccurate.', 'event_espresso')
            );
        }
        if ($new_txn_status !== $this->status_ID()) {
            $this->set_status($new_txn_status);
            if ($update) {
                return $this->save() ? true : false;
            }
        }
        return false;
    }


    /**
     * Updates the transaction's status and total_paid based on all the payments
     * that apply to it
     *
     * @deprecated
     * @return array|bool
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws ReflectionException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     */
    public function update_based_on_payments()
    {
        EE_Error::doing_it_wrong(
            __CLASS__ . '::' . __FUNCTION__,
            sprintf(
                __('This method is deprecated. Please use "%s" instead', 'event_espresso'),
                'EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()'
            ),
            '4.6.0'
        );
        /** @type EE_Transaction_Processor $transaction_processor */
        $transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
        return $transaction_processor->update_transaction_and_registrations_after_checkout_or_payment($this);
    }


    /**
     * @return string
     */
    public function old_txn_status()
    {
        return $this->_old_txn_status;
    }


    /**
     * @param string $old_txn_status
     */
    public function set_old_txn_status($old_txn_status)
    {
        // only set the first time
        if ($this->_old_txn_status === null) {
            $this->_old_txn_status = $old_txn_status;
        }
    }


    /**
     * reg_status_updated
     *
     * @return bool
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function txn_status_updated()
    {
        return $this->status_ID() !== $this->_old_txn_status && $this->_old_txn_status !== null;
    }


    /**
     * _reg_steps_completed
     * if $check_all is TRUE, then returns TRUE if ALL reg steps have been marked as completed,
     * if a $reg_step_slug is provided, then this step will be skipped when testing for completion
     * if $check_all is FALSE and a $reg_step_slug is provided, then ONLY that reg step will be tested for completion
     *
     * @param string $reg_step_slug
     * @param bool   $check_all
     * @return bool|int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    private function _reg_steps_completed($reg_step_slug = '', $check_all = true)
    {
        $reg_steps = $this->reg_steps();
        if (! is_array($reg_steps) || empty($reg_steps)) {
            return false;
        }
        // loop thru reg steps array)
        foreach ($reg_steps as $slug => $reg_step_completed) {
            // if NOT checking ALL steps (only checking one step)
            if (! $check_all) {
                // and this is the one
                if ($slug === $reg_step_slug) {
                    return $reg_step_completed;
                }
                // skip to next reg step in loop
                continue;
            }
            // $check_all must be true, else we would never have gotten to this point
            if ($slug === $reg_step_slug) {
                // if we reach this point, then we are testing either:
                // all_reg_steps_completed_except() or
                // all_reg_steps_completed_except_final_step(),
                // and since this is the reg step EXCEPTION being tested
                // we want to return true (yes true) if this reg step is NOT completed
                // ie: "is everything completed except the final step?"
                // "that is correct... the final step is not completed, but all others are."
                return $reg_step_completed !== true;
            }
            if ($reg_step_completed !== true) {
                // if any reg step is NOT completed, then ALL steps are not completed
                return false;
            }
        }
        return true;
    }


    /**
     * all_reg_steps_completed
     * returns:
     *    true if ALL reg steps have been marked as completed
     *        or false if any step is not completed
     *
     * @return bool
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function all_reg_steps_completed()
    {
        return $this->_reg_steps_completed();
    }


    /**
     * all_reg_steps_completed_except
     * returns:
     *        true if ALL reg steps, except a particular step that you wish to skip over, have been marked as completed
     *        or false if any other step is not completed
     *        or false if ALL steps are completed including the exception you are testing !!!
     *
     * @param string $exception
     * @return bool
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function all_reg_steps_completed_except($exception = '')
    {
        return $this->_reg_steps_completed($exception);
    }


    /**
     * all_reg_steps_completed_except
     * returns:
     *        true if ALL reg steps, except the final step, have been marked as completed
     *        or false if any step is not completed
     *    or false if ALL steps are completed including the final step !!!
     *
     * @return bool
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function all_reg_steps_completed_except_final_step()
    {
        return $this->_reg_steps_completed('finalize_registration');
    }


    /**
     * reg_step_completed
     * returns:
     *    true if a specific reg step has been marked as completed
     *    a Unix timestamp if it has been initialized but not yet completed,
     *    or false if it has not yet been initialized
     *
     * @param string $reg_step_slug
     * @return bool|int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function reg_step_completed($reg_step_slug)
    {
        return $this->_reg_steps_completed($reg_step_slug, false);
    }


    /**
     * completed_final_reg_step
     * returns:
     *    true if the finalize_registration reg step has been marked as completed
     *    a Unix timestamp if it has been initialized but not yet completed,
     *    or false if it has not yet been initialized
     *
     * @return bool|int
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function final_reg_step_completed()
    {
        return $this->_reg_steps_completed('finalize_registration', false);
    }


    /**
     * set_reg_step_initiated
     * given a valid TXN_reg_step, this sets it's value to a unix timestamp
     *
     * @param string $reg_step_slug
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_reg_step_initiated($reg_step_slug)
    {
        return $this->_set_reg_step_completed_status($reg_step_slug, time());
    }


    /**
     * set_reg_step_completed
     * given a valid TXN_reg_step, this sets the step as completed
     *
     * @param string $reg_step_slug
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_reg_step_completed($reg_step_slug)
    {
        return $this->_set_reg_step_completed_status($reg_step_slug, true);
    }


    /**
     * set_reg_step_completed
     * given a valid TXN_reg_step slug, this sets the step as NOT completed
     *
     * @param string $reg_step_slug
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function set_reg_step_not_completed($reg_step_slug)
    {
        return $this->_set_reg_step_completed_status($reg_step_slug, false);
    }


    /**
     * set_reg_step_completed
     * given a valid reg step slug, this sets the TXN_reg_step completed status which is either:
     *
     * @param  string      $reg_step_slug
     * @param  boolean|int $status
     * @return boolean
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    private function _set_reg_step_completed_status($reg_step_slug, $status)
    {
        // validate status
        $status = is_bool($status) || is_int($status) ? $status : false;
        // get reg steps array
        $txn_reg_steps = $this->reg_steps();
        // if reg step does NOT exist
        if (! isset($txn_reg_steps[ $reg_step_slug ])) {
            return false;
        }
        // if  we're trying to complete a step that is already completed
        if ($txn_reg_steps[ $reg_step_slug ] === true) {
            return true;
        }
        // if  we're trying to complete a step that hasn't even started
        if ($status === true && $txn_reg_steps[ $reg_step_slug ] === false) {
            return false;
        }
        // if current status value matches the incoming value (no change)
        // type casting as int means values should collapse to either 0, 1, or a timestamp like 1234567890
        if ((int) $txn_reg_steps[ $reg_step_slug ] === (int) $status) {
            // this will happen in cases where multiple AJAX requests occur during the same step
            return true;
        }
        // if we're trying to set a start time, but it has already been set...
        if (is_numeric($status) && is_numeric($txn_reg_steps[ $reg_step_slug ])) {
            // skip the update below, but don't return FALSE so that errors won't be displayed
            return true;
        }
        // update completed status
        $txn_reg_steps[ $reg_step_slug ] = $status;
        $this->set_reg_steps($txn_reg_steps);
        $this->save();
        return true;
    }


    /**
     * remove_reg_step
     * given a valid TXN_reg_step slug, this will remove (unset)
     * the reg step from the TXN reg step array
     *
     * @param string $reg_step_slug
     * @return void
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function remove_reg_step($reg_step_slug)
    {
        // get reg steps array
        $txn_reg_steps = $this->reg_steps();
        unset($txn_reg_steps[ $reg_step_slug ]);
        $this->set_reg_steps($txn_reg_steps);
    }


    /**
     * toggle_failed_transaction_status
     * upgrades a TXNs status from failed to abandoned,
     * meaning that contact information has been captured for at least one registrant
     *
     * @param bool $save
     * @return bool
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function toggle_failed_transaction_status($save = true)
    {
        // if TXN status is still set as "failed"...
        if ($this->status_ID() === EEM_Transaction::failed_status_code) {
            $this->set_status(EEM_Transaction::abandoned_status_code);
            if ($save) {
                $this->save();
            }
            return true;
        }
        return false;
    }


    /**
     * toggle_abandoned_transaction_status
     * upgrades a TXNs status from failed or abandoned to incomplete
     *
     * @return bool
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     */
    public function toggle_abandoned_transaction_status()
    {
        // if TXN status has not been updated already due to a payment, and is still set as "failed" or "abandoned"...
        $txn_status = $this->status_ID();
        if ($txn_status === EEM_Transaction::failed_status_code
            || $txn_status === EEM_Transaction::abandoned_status_code
        ) {
            // if a contact record for the primary registrant has been created
            if ($this->primary_registration() instanceof EE_Registration
                && $this->primary_registration()->attendee() instanceof EE_Attendee
            ) {
                $this->set_status(EEM_Transaction::incomplete_status_code);
            } else {
                // no contact record? yer abandoned!
                $this->set_status(EEM_Transaction::abandoned_status_code);
            }
            return true;
        }
        return false;
    }


    /**
     * checks if an Abandoned TXN has any related payments, and if so,
     * updates the TXN status based on the amount paid
     *
     * @throws EE_Error
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws InvalidArgumentException
     * @throws RuntimeException
     * @throws ReflectionException
     */
    public function verify_abandoned_transaction_status()
    {
        if ($this->status_ID() !== EEM_Transaction::abandoned_status_code) {
            return;
        }
        $payments = $this->get_many_related('Payment');
        if (! empty($payments)) {
            foreach ($payments as $payment) {
                if ($payment instanceof EE_Payment) {
                    // kk this TXN should NOT be abandoned
                    $this->update_status_based_on_total_paid();
                    if (! (defined('DOING_AJAX') && DOING_AJAX) && is_admin()) {
                        EE_Error::add_attention(
                            sprintf(
                                esc_html__(
                                    'The status for Transaction #%1$d has been updated from "Abandoned" to "%2$s", because at least one payment has been made towards it. If the payment appears in the "Payment Details" table below, you may need to edit its status and/or other details as well.',
                                    'event_espresso'
                                ),
                                $this->ID(),
                                $this->pretty_status()
                            )
                        );
                    }
                    // get final reg step status
                    $finalized = $this->final_reg_step_completed();
                    // if the 'finalize_registration' step has been initiated (has a timestamp)
                    // but has not yet been fully completed (TRUE)
                    if (is_int($finalized) && $finalized !== false && $finalized !== true) {
                        $this->set_reg_step_completed('finalize_registration');
                        $this->save();
                    }
                }
            }
        }
    }


    /**
     * @since 4.10.4.p
     * @throws EE_Error
     * @throws InvalidArgumentException
     * @throws InvalidDataTypeException
     * @throws InvalidInterfaceException
     * @throws ReflectionException
     * @throws RuntimeException
     */
    public function recalculateLineItems()
    {
        $total_line_item = $this->total_line_item(false);
        if ($total_line_item instanceof EE_Line_Item) {
            EEH_Line_Item::resetIsTaxableForTickets($total_line_item);
            return EEH_Line_Item::apply_taxes($total_line_item, true);
        }
        return false;
    }
}
