class-gf-paystack.php

<?php

defined('ABSPATH') || die();

// Include the payment add-on framework.
GFForms::include_payment_addon_framework();

/**
 * Class GFPaystack
 *
 * Primary class to manage the Paystack add-on.
 *
 * @since 1.0
 *
 * @uses GFPaymentAddOn
 */
class GFPaystack extends GFPaymentAddOn
{
    /**
     * Contains an instance of this class, if available.
     *
     * @since  1.0
     * @access private
     *
     * @used-by GFPaystack::get_instance()
     *
     * @var object $_instance If available, contains an instance of this class.
     */
    private static $_instance = null;

    /** @var string|null */
    protected $webhook_mode = null;

    /**
     * Defines the version of the Paystack Add-On.
     *
     * @since  1.0
     * @access protected
     *
     * @used-by GFPaystack::scripts()
     *
     * @var string $_version Contains the version, defined from paystack.php
     */
    protected $_version = GF_PAYSTACK_VERSION;

    /**
     * Defines the minimum Gravity Forms version required.
     *
     * @since  1.0
     * @access protected
     *
     * @var string $_min_gravityforms_version The minimum version required.
     */
    protected $_min_gravityforms_version = '2.0';

    /**
     * Defines the plugin slug.
     *
     * @since  1.0
     * @access protected
     *
     * @var string $_slug The slug used for this plugin.
     */
    protected $_slug = 'gravityformspaystack';

    /**
     * Defines the main plugin file.
     *
     * @since  1.0
     * @access protected
     *
     * @var string $_path The path to the main plugin file, relative to the plugins folder.
     */
    protected $_path = 'gravityformspaystack/paystack.php';

    /**
     * Defines the full path to this class file.
     *
     * @since  1.0
     * @access protected
     *
     * @var string $_full_path The full path.
     */
    protected $_full_path = __FILE__;

    /**
     * Defines the URL where this Add-On can be found.
     *
     * @since  1.0
     * @access protected
     *
     * @var string $_url The URL of the Add-On.
     */
    protected $_url = 'https://paystack.com/docs/libraries-and-plugins/plugins#wordpress';

    /**
     * Defines the title of this Add-On.
     *
     * @since  1.0
     * @access protected
     *
     * @var string $_title The title of the Add-On.
     */
    protected $_title = 'Paystack Add-On for Gravity Forms';

    /**
     * Defines the short title of the Add-On.
     *
     * @since  1.0
     * @access protected
     *
     * @var string $_short_title The short title.
     */
    protected $_short_title = 'Paystack';

    /**
     * Defines if user will not be able to create feeds for a form until a credit card field has been added.
     *
     * @since  1.0
     * @access protected
     *
     * @var bool $_requires_credit_card false.
     */
    protected $_requires_credit_card = false;

    /**
     * Defines if callbacks/webhooks/IPN will be enabled and the appropriate database table will be created.
     *
     * @since  1.0
     * @access protected
     *
     * @var bool $_supports_callbacks true
     */
    protected $_supports_callbacks = true;

    /**
     * Paystack requires monetary amounts to be formatted as the smallest unit for the currency being used e.g. kobo, pesewas, cent
     *
     * @since  1.10.1
     * @access protected
     *
     * @var bool $_requires_smallest_unit true
     */
    protected $_requires_smallest_unit = true;

    /**
     * Defines the capability needed to access the Add-On settings page.
     *
     * @since  1.0
     * @access protected
     * @var    string $_capabilities_settings_page The capability needed to access the Add-On settings page.
     */
    protected $_capabilities_settings_page = 'gravityforms_paystack';

    /**
     * Defines the capability needed to access the Add-On form settings page.
     *
     * @since  1.0
     * @access protected
     * @var    string $_capabilities_form_settings The capability needed to access the Add-On form settings page.
     */
    protected $_capabilities_form_settings = 'gravityforms_paystack';

    /**
     * Defines the capability needed to uninstall the Add-On.
     *
     * @since  1.0
     * @access protected
     * @var    string $_capabilities_uninstall The capability needed to uninstall the Add-On.
     */
    protected $_capabilities_uninstall = 'gravityforms_paystack_uninstall';

    /**
     * Defines the capabilities needed for the Paystack Add-On
     *
     * @since  1.0
     * @access protected
     * @var    array $_capabilities The capabilities needed for the Add-On
     */
    protected $_capabilities = array('gravityforms_paystack', 'gravityforms_paystack_uninstall');

    /**
     * Holds the custom meta key currently being processed. Enables the key to be passed to the gform_paystack_field_value filter.
     *
     * @since  1.0
     * @access protected
     *
     * @used-by GFPaystack::maybe_override_field_value()
     *
     * @var string $_current_meta_key The meta key currently being processed.
     */
    protected $_current_meta_key = '';

    /**
     * Enable rate limits to log card errors etc.
     *
     * @since 1.0
     *
     * @var bool
     */
    protected $_enable_rate_limits = true;

    /**
     * Paystack API Wrapper
     *
     * @var GFPaystackApi
     */
    protected $paystack_api;

    /**
     * Get an instance of this class.
     *
     * @since  1.0
     * @access public
     *
     * @uses GFPaystack
     * @uses GFPaystack::$_instance
     *
     * @return object GFPaystack
     */
    public static function get_instance()
    {
        if (null === self::$_instance) {
            self::$_instance = new GFPaystack();
        }

        return self::$_instance;
    }

    /**
     * Load the Paystack credit card field.
     *
     * @since 1.0
     */
    public function pre_init()
    {
        // For form confirmation redirection, this must be called in `wp`,
        // or confirmation redirect to a page would throw PHP fatal error.
        // Run before calling parent method. We don't want to run anything else before displaying thank you page.
        add_action('wp', array($this, 'maybe_thankyou_page'), 5);

        parent::pre_init();
    }

    public function init()
    {
        parent::init();

        add_filter('gform_currencies', array($this, 'add_paystack_currencies'));
    }

    // # PLUGIN SETTINGS -----------------------------------------------------------------------------------------------

    /**
     * Configures the settings which should be rendered on the add-on settings tab.
     *
     * @access public
     *
     * @used-by GFAddOn::maybe_save_plugin_settings()
     * @used-by GFAddOn::plugin_settings_page()
     * @uses    GFPaystack::api_settings_fields()
     * @uses    GFPaystack::get_webhooks_section_description()
     *
     * @return array Plugin settings fields to add.
     */
    public function plugin_settings_fields()
    {
        $fields = array(
        array(
        'title'  => esc_html__('Configuration', 'gravityformspaystack'),
        'fields' => $this->api_settings_fields(),
        ),
        );

        return $fields;
    }

    /**
     * Define the settings which appear in the Paystack API section.
     *
     * @access public
     *
     * @used-by GFPaystack::plugin_settings_fields()
     *
     * @return array The API settings fields.
     */
    public function api_settings_fields()
    {
        $api_mode = '';

        if ($this->is_detail_page() && empty($api_mode)) {
            $api_mode = $this->get_plugin_setting('api_mode');
        }

        $fields = array(
        array(
        'name'          => 'api_mode',
        'label'         => esc_html__('Mode', 'gravityformspaystack'),
        'type'          => 'radio',
        'default_value' => $api_mode,
        'choices'       => array(
                    array(
                        'label' => esc_html__('Live', 'gravityformspaystack'),
                        'value' => 'live',
        ),
        array(
         'label' => esc_html__('Test', 'gravityformspaystack'),
         'value' => 'test',
        ),
        ),
        'horizontal'    => true,
        )
        );

        $credentials_fields = array(
        array(
        'name'  => 'test_public_key',
        'label' => esc_html__('Test Public Key', 'gravityformspaystack'),
        'type'  => 'text',
        'class'    => 'medium',
        ),
        array(
        'name'  => 'test_secret_key',
        'label' => esc_html__('Test Secret Key', 'gravityformspaystack'),
        'type'  => 'text',
        'class'    => 'medium',
        ),
        array(
        'name'  => 'live_public_key',
        'label' => esc_html__('Live Public Key', 'gravityformspaystack'),
        'type'  => 'text',
        'class'    => 'medium',
        ),
        array(
        'name'  => 'live_secret_key',
        'label' => esc_html__('Live Secret Key', 'gravityformspaystack'),
        'type'  => 'text',
        'class'    => 'medium',
        ),
        );

        $fields = array_merge($fields, $credentials_fields);

        $webhook_fields = array(
        array(
        'name'        => 'webhooks_enabled',
        'label'       => esc_html__('Webhooks Enabled?', 'gravityformspaystack'),
        'type'        => 'checkbox',
        'horizontal'  => true,
        'required'    => ($this->get_current_feed_id() || !isset($_GET['fid'])) ? true : false,
        'description' => $this->get_webhooks_section_description(),
        'dependency'  => $this->is_detail_page() ? array($this, 'is_feed_paystack_connect_enabled') : false,
        'choices'     => array(
                    array(
                        'label' => esc_html__('I have enabled the Gravity Forms webhook URL in my Paystack account.', 'gravityformspaystack'),
                        'value' => 1,
                        'name'  => 'webhooks_enabled',
        ),
        ),
        )
        );

        $fields = array_merge($fields, $webhook_fields);

        return $fields;
    }

    /**
     * Define the markup to be displayed for the webhooks section description.
     *
     * @since  Unknown
     * @access public
     *
     * @used-by GFPaystack::plugin_settings_fields()
     * @uses    GFPaystack::get_webhook_url()
     *
     * @return string HTML formatted webhooks description.
     */
    public function get_webhooks_section_description()
    {
        ob_start();
        ?>
        <a href="javascript:void(0);" onclick="tb_show('Webhook Instructions', '#TB_inline?width=500&inlineId=paystack-webhooks-instructions', '');" onkeypress="tb_show('Webhook Instructions', '#TB_inline?width=500&inlineId=paystack-webhooks-instructions', '');">
        <?php esc_html_e('View Instructions', 'gravityformspaystack'); ?>
        </a>
        </p>

        <div id="paystack-webhooks-instructions" style="display:none;">
            <ol class="paystack-webhooks-instructions">
                <li>
                    <p><?php esc_html_e('Click the following link and log in to access your Paystack Webhooks management page:', 'gravityformspaystack'); ?> </p>
                    <a href="https://dashboard.paystack.com/#/settings/developer" target="_blank">https://dashboard.paystack.com/#/settings/developer</a>
                </li>
                <li>
                    <p>
        <?php esc_html_e('Enter the following URL in the "Webhook URL" field:', 'gravityformspaystack'); ?>
                        <br />
                        <code><?php echo $this->get_webhook_url($this->get_current_feed_id()); ?></code>
                    </p>
                </li>
                <li><?php esc_html_e('Save Changes.', 'gravityformspaystack'); ?></li>
            </ol>
        </div>

        <?php
        return ob_get_clean();
    }

    // # FEED SETTINGS -------------------------------------------------------------------------------------------------

    /**
     * Configures the settings which should be rendered on the feed edit page.
     *
     * @access public
     *
     * @uses GFPaymentAddOn::feed_settings_fields()
     * @uses GFAddOn::replace_field()
     * @uses GFAddOn::get_setting()
     * @uses GFAddOn::add_field_after()
     * @uses GFAddOn::remove_field()
     * @uses GFAddOn::add_field_before()
     *
     * @return array The feed settings.
     */
    public function feed_settings_fields()
    {
        // Get default payment feed settings fields.
        $default_settings = parent::feed_settings_fields();

        $fields = array(
        array(
        'name'          => 'mode',
        'label'         => esc_html__('Mode', 'gravityformspaystack'),
        'type'          => 'radio',
        'choices'       => array(
        array('id' => 'gf_paystack_live_mode', 'label' => esc_html__('Live', 'gravityformspaystack'), 'value' => 'live'),
        array('id' => 'gf_paystack_test_mode', 'label' => esc_html__('Test', 'gravityformspaystack'), 'value' => 'test'),
        ),
        'horizontal'    => true,
        'default_value' => 'live',
        'tooltip'       => '<h6>' . esc_html__('Mode', 'gravityformspaystack') . '</h6>' . esc_html__('Select Live to receive payments in production. Select Test for testing purposes when using the Paystack development sandbox.', 'gravityformspaystack')
        ),
        );

        $default_settings = parent::add_field_after('feedName', $fields, $default_settings);

        // Add donation to transaction type drop down 
        // $transaction_type = parent::get_field('transactionType', $default_settings);
        // $choices          = $transaction_type['choices'];
        // $add_donation     = true;

        // foreach ($choices as $choice) {
        //     // Add donation option if it does not already exist
        //     if ($choice['value'] == 'donation') {
        //         $add_donation = false;
        //     }
        // }

        // if ($add_donation) {
        //     // Add donation transaction type
        //     $choices[] = array('label' => __('Donations', 'gravityformspaystack'), 'value' => 'donation');
        // }

        // $transaction_type['choices'] = $choices;
        // $default_settings = $this->replace_field('transactionType', $transaction_type, $default_settings);

        // Add send invoice field if the feed transaction type is a subscription.
        if ($this->get_setting('transactionType') === 'subscription') {
            $invoice_settings = array(
            'name'        => 'sendInvoices',
            'label'     => esc_html__('Send Invoices', 'gravityformspaystack'),
            'type'        => 'checkbox',
            'choices'     => array(
            array(
            'label' => 'Check if you want invoices to be sent to your customers',
            'name'  => 'sendInvoices',
            ),
            ),
            'tooltip'    => '<h6>' . esc_html__('Send Invoices', 'gravityformspaystack') . '</h6>' . esc_html__('If enabled, Paystack can send an email invoice to customers.', 'gravityformspaystack'),
            );

            $default_settings = $this->add_field_before('setupFee', $invoice_settings, $default_settings);
        }

        // hide default display of setup fee, not used by Paystack
        $default_settings = parent::remove_field('setupFee', $default_settings);

        // // Prepare trial period field.
        // $trial_period_field = array(
        //     'name'                => 'trialPeriod',
        //     'label'               => esc_html__('Trial Period', 'gravityformspaystack'),
        //     'style'               => 'width:40px;text-align:center;',
        //     'type'                => 'trial_period',
        //     'after_input'         => '&nbsp;' . esc_html__('days', 'gravityformspaystack'),
        //     'validation_callback' => array($this, 'validate_trial_period'),
        // );

        // // Add trial period field.
        // $default_settings = $this->add_field_after('trial', $trial_period_field, $default_settings);

        // Hide default display of trial, not used by Paystack
        $default_settings = parent::remove_field('trial', $default_settings);

        // Add subscription name field.
        $plan_name_field = array(
        'name'    => 'planName',
        'label'   => esc_html__('Plan Name', 'gravityformspaystack'),
        'type'    => 'text',
        'class'   => 'medium merge-tag-support mt-hide_all_fields mt-position-right',
        'tooltip' => '<h6>' . esc_html__('Plan Name', 'gravityformspaystack') . '</h6>' . esc_html__('Enter a name for the subscription. It will be displayed on the payment form as well as the Paystack dashboard.', 'gravityformspaystack'),
        );

        $default_settings  = $this->add_field_before('recurringAmount', $plan_name_field, $default_settings);

        // Customer information fields.
        $customer_info_field = array(
        'name'       => 'customerInformation',
        'label'      => esc_html__('Customer Information', 'gravityformspaystack'),
        'type'       => 'field_map',
        'field_map'  => array(
        array(
                    'name'       => 'email',
                    'label'      => esc_html__('Email Address', 'gravityformspaystack'),
                    'required'   => true,
                    'field_type' => array('email', 'hidden'),
                    'tooltip'    => '<h6>' . esc_html__('Email', 'gravityformspaystack') . '</h6>' . esc_html__('You can specify an email field and it will be sent to the Paystack screen as the customer\'s email.', 'gravityformspaystack'),
        ),
        array(
        'name'     => 'first_name',
        'label'    => esc_html__('First Name', 'gravityformspaystack'),
        'required' => ($this->get_setting('transactionType') == 'subscription') ? true : false,
        ),
        array(
        'name'     => 'last_name',
        'label'    => esc_html__('Last Name', 'gravityformspaystack'),
        'required' => ($this->get_setting('transactionType') == 'subscription') ? true : false,
        ),
        array(
        'name'         => 'phone',
        'label'        => esc_html__('Phone Number', 'gravityformspaystack'),
        'required'     => false,
        ),
        ),
        );

        if ($this->get_setting('transactionType') == 'subscription') {
            $customer_info_field['field_map'][] = array(
            'name'      => 'recurring_times',
            'label'     => esc_html__('Recurring Times', 'gravityformspaystack'),
            'required'  => false,
            'tooltip'    => '<h6>' . esc_html__('Recurring Times', 'gravityformspaystack') . '</h6>' . esc_html__('(OPTIONAL). Setting this will allow users to select then number of times a charge should happen during a subscrption to a plan. This will override the "Recurring Times" option under "Subscription Settings" section above. It is recommended to create a select field. Values can be "2-100" or "0" for indefinite. In case an empty value or 1 is passed, the plugin will fall back to the other aforementioned "Recurring Times" option.', 'gravityformspaystack'),
            );
        }

        // Add customer information fields.
        $default_settings = $this->add_field_before('billingInformation', $customer_info_field, $default_settings);

        // Prepare meta data field.
        $custom_meta = array(
        array(
        'name'                => 'metaData',
        'label'               => esc_html__('Metadata', 'gravityformspaystack'),
        'type'                => 'dynamic_field_map',
        'limit'                  => 20,
        'tooltip'             => '<h6>' . esc_html__('Metadata', 'gravityformspaystack') . '</h6>' . esc_html__('You may send custom meta information to Paystack. A maximum of 20 custom keys may be sent.', 'gravityformspaystack'),
        'validation_callback' => array($this, 'validate_custom_meta'),
        ),
        );

        // Add meta data field.
        $default_settings = $this->add_field_after('billingInformation', $custom_meta, $default_settings);

        // hide default display of billing Information if transaction type is donation
        if ($this->get_setting('transactionType') === 'donation') {
            $default_settings = parent::remove_field('billingInformation', $default_settings);
        }

        return $default_settings;
    }

    /**
     * Define the markup for the billing_cycle type field.
     *
     * @access public
     *
     * @return array The feed settings.
     */
    public function settings_billing_cycle($field, $echo = true)
    {
        $intervals = $this->supported_billing_intervals();

        $choices = array();
        foreach ($intervals as $unit => $interval) {
            if (!empty($interval)) {
                $choices[] = array('value' => $unit, 'label' => $interval['label']);
            }
        }

        //Interval drop down
        $interval_field = array(
        'name'     => $field['name'] . '_unit',
        'type'     => 'select',
        'onchange' => "loadBillingLength('" . esc_attr($field['name']) . "')",
        'choices'  => $choices,
        );

        $html = '&nbsp' . $this->settings_select($interval_field, false);

        $html .= "<script type='text/javascript'>var " . $field['name'] . '_intervals = ' . json_encode($intervals) . ';</script>';

        if ($echo) {
            echo $html;
        }

        return $html;
    }

    /**
     * Define the choices available in the billing cycle dropdowns.
     *
     * @access public
     *
     * @used-by GFPaymentAddOn::settings_billing_cycle()
     *
     * @return array Billing intervals that are supported.
     */
    public function supported_billing_intervals()
    {
        return array(
        'hourly'   => array('label' => esc_html__('Hourly', 'gravityformspaystack')),
        'daily'    => array('label' => esc_html__('Daily', 'gravityformspaystack')),
        'weekly'   => array('label' => esc_html__('Weekly', 'gravityformspaystack')),
        'monthly'  => array('label' => esc_html__('Monthly', 'gravityformspaystack')),
        'annually'   => array('label' => esc_html__('Annually', 'gravityformspaystack')),
        'biannually' => array('label' => esc_html__('Biannually', 'gravityformspaystack')),
        );
    }

    /**
     * Define the markup for the trial type field.
     *
     * @since  Unknown
     * @access public
     *
     * @uses GFAddOn::settings_checkbox()
     *
     * @param array     $field The field properties.
     * @param bool|true $echo  Should the setting markup be echoed. Defaults to true.
     *
     * @return string|void The HTML markup if $echo is set to false. Void otherwise.
     */
    public function settings_trial($field, $echo = true)
    {
        // Prepare enabled field settings.
        $enabled_field = array(
        'name'       => $field['name'] . '_checkbox',
        'type'       => 'checkbox',
        'horizontal' => true,
        'choices'    => array(
        array(
        'label'    => esc_html__('Enabled', 'gravityformspaystack'),
        'name'     => $field['name'] . '_enabled',
        'value'    => '1',
        'onchange' => "if(jQuery(this).prop('checked')){
						jQuery('#gaddon-setting-row-trialPeriod').show('slow');
					} else {
						jQuery('#gaddon-setting-row-trialPeriod').hide('slow');
						jQuery('#trialPeriod').val( '' );
					}",
        ),
        ),
        );

        // Get checkbox markup.
        $html = $this->settings_checkbox($enabled_field, false);

        // Echo setting markup, if enabled.
        if ($echo) {
            echo $html;
        }

        return $html;
    }

    /**
     * Define the markup for the trial_period type field.
     *
     * @since  Unknown
     * @access public
     *
     * @uses GFAddOn::settings_text()
     * @uses GFAddOn::field_failed_validation()
     * @uses GFAddOn::get_error_icon()
     *
     * @param array     $field The field properties.
     * @param bool|true $echo  Should the setting markup be echoed. Defaults to true.
     *
     * @return string|void The HTML markup if $echo is set to false. Void otherwise.
     */
    public function settings_trial_period($field, $echo = true)
    {
        // Get text input markup.
        $html = $this->settings_text($field, false);

        // Prepare validation placeholder name.
        $validation_placeholder = array('name' => 'trialValidationPlaceholder');

        // Add validation indicator.
        if ($this->field_failed_validation($validation_placeholder)) {
            $html .= '&nbsp;' . $this->get_error_icon($validation_placeholder);
        }

        // If trial is not enabled and setup fee is enabled, hide field.
        $html .= '
			<script type="text/javascript">
			if( ! jQuery( "#trial_enabled" ).is( ":checked" ) || jQuery( "#setupFee_enabled" ).is( ":checked" ) ) {
				jQuery( "#trial_enabled" ).prop( "checked", false );
				jQuery( "#gaddon-setting-row-trialPeriod" ).hide();
			}
			</script>';

        // Echo setting markup, if enabled.
        if ($echo) {
            echo $html;
        }

        return $html;
    }

    /**
     * Prepare fields for field mapping in feed settings.
     *
     * @return array $fields
     */
    public function billing_info_fields()
    {
        $fields = array(
        array(
        'name'       => 'address_line1',
        'label'      => __('Address', 'gravityformsconstantcontact'),
        'required'   => false,
        'field_type' => array('address'),
        ),
        array(
        'name'       => 'address_line2',
        'label'      => __('Address 2', 'gravityformsconstantcontact'),
        'required'   => false,
        'field_type' => array('address'),
        ),
        array(
        'name'       => 'address_city',
        'label'      => __('City', 'gravityformsconstantcontact'),
        'required'   => false,
        'field_type' => array('address'),
        ),
        array(
        'name'       => 'address_state',
        'label'      => __('State', 'gravityformsconstantcontact'),
        'required'   => false,
        'field_type' => array('address'),
        ),
        array(
        'name'       => 'address_zip',
        'label'      => __('Zip', 'gravityformsconstantcontact'),
        'required'   => false,
        'field_type' => array('address'),
        ),
        array(
        'name'       => 'address_country',
        'label'      => __('Country', 'gravityformsconstantcontact'),
        'required'   => false,
        'field_type' => array('address'),
        ),
        );

        return $fields;
    }

    /**
     * Validate the custom_meta type field.
     *
     * @access public
     *
     * @uses GFAddOn::get_posted_settings()
     * @uses GFAddOn::set_field_error()
     *
     * @param array $field The field properties. Not used.
     *
     * @return void
     */
    public function validate_custom_meta($field)
    {
        /*
        * Number of keys is limited to 20.
        * Interface should control this, validating just in case.
        * Key names have maximum length of 40 characters.
        */

        // Get metadata from posted settings.
        $settings  = $this->get_posted_settings();
        $meta_data = $settings['metaData'];

        // If metadata is not defined, return.
        if (empty($meta_data)) {
            return;
        }

        // Get number of metadata items.
        $meta_count = count($meta_data);

        // If there are more than 20 metadata keys, set field error.
        if ($meta_count > 20) {
            $this->set_field_error(array(esc_html__('You may only have 20 custom keys.'), 'gravityformspaystack'));
            return;
        }

        // Loop through metadata and check the key name length (custom_key).
        foreach ($meta_data as $meta) {
            if (empty($meta['custom_key']) && !empty($meta['value'])) {
                $this->set_field_error(array('name' => 'metaData'), esc_html__("A field has been mapped to a custom key without a name. Please enter a name for the custom key, remove the metadata item, or return the corresponding drop down to 'Select a Field'.", 'gravityformspaystack'));
                break;
            } else if (strlen($meta['custom_key']) > 40) {
                $this->set_field_error(array('name' => 'metaData'), sprintf(esc_html__('The name of custom key %s is too long. Please shorten this to 40 characters or less.', 'gravityformspaystack'), $meta['custom_key']));
                break;
            }
        }
    }

    /**
     * Prevent the 'options' checkboxes setting being included on the feed.
     *
     * @access public
     *
     * @used-by GFPaymentAddOn::other_settings_fields()
     *
     * @return false
     */
    public function option_choices()
    {
        return false;
    }

    /**
     * Add supported notification events.
     *
     * @access public
     *
     * @used-by GFFeedAddOn::notification_events()
     * @uses    GFFeedAddOn::has_feed()
     *
     * @param array $form The form currently being processed.
     *
     * @return array|false The supported notification events. False if feed cannot be found within $form.
     */
    public function supported_notification_events($form)
    {
        // If this form does not have a Paystack feed, return false.
        if (!$this->has_feed($form['id'])) {
            return false;
        }

        // Return Paystack notification events.
        return array(
        'complete_payment'          => esc_html__('Payment Completed', 'gravityformspaystack'),
        'refund_payment'            => esc_html__('Payment Refunded', 'gravityformspaystack'),
        'fail_payment'              => esc_html__('Payment Failed', 'gravityformspaystack'),
        'create_subscription'       => esc_html__('Subscription Created', 'gravityformspaystack'),
        'cancel_subscription'       => esc_html__('Subscription Canceled', 'gravityformspaystack'),
        'add_subscription_payment'  => esc_html__('Subscription Payment Added', 'gravityformspaystack'),
        'fail_subscription_payment' => esc_html__('Subscription Payment Failed', 'gravityformspaystack'),
        );
    }

    // # PAYSTACK TRANSACTIONS -------------------------------------------------------------------------------------------

    /**
     * Useful when developing a payment gateway that processes the payment outside of the website (i.e. Paystack Redirect).
     *
     * @since  Unknown
     * @access public
     *
     * @used-by GFPaymentAddOn::entry_post_save()
     *
     * @param array $feed            Active payment feed containing all the configuration data.
     * @param array $submission_data Contains form field data submitted by the user as well as payment information (i.e. payment amount, setup fee, line items, etc...).
     * @param array $form            Current form array containing all form settings.
     * @param array $entry           Current entry array containing entry information (i.e data submitted by users).
     *
     * @return void|string Return a full URL (including http:// or https://) to the payment processor.
     */
    public function redirect_url($feed, $submission_data, $form, $entry)
    {
        // Don't process redirect url if request is a Paystack return
        if (!rgempty('gf_paystack_return', $_GET)) {
            return false;
        }

        // Getting mode (Live (Production) or Test (Sandbox))
        $mode = $feed['meta']['mode'];

        // Setup the Paystack API
        $this->paystack_api($mode);

        // Get the transaction type
        $transaction_type = $feed['meta']['transactionType'];

        // Getting the product status
        $is_product = $feed['meta']['transactionType'] === 'product';

        // Getting the subscription status
        $is_subscription = $feed['meta']['transactionType'] === 'subscription';

        // URL that will listen to callback from Paystack
        $page_url = get_bloginfo('url');
        $ids_query = "ids={$entry['id']}|{$feed['id']}|{$form['id']}";
        $ids_query .= '&hash=' . wp_hash($ids_query);

        $return_url = add_query_arg('gf_paystack_return', base64_encode($ids_query), $page_url);

        // $setup_fee      = rgar($submission_data, 'setup_fee');
        // $trial_amount   = rgar($submission_data, 'trial');
        $payment_amount = rgar($submission_data, 'payment_amount');

        // Currency
        $currency = rgar($entry, 'currency');

        // Customer Info
        $customer_info = $this->get_fields_meta_data($feed, $entry, $this->get_customer_fields());

        // Get feed custom metadata
        $custom_data = $this->get_paystack_meta_data($feed, $entry, $form);

        // $custom_data[] = [
        //     'display_name' => 'Plugin Name',
        //     'variable_name' => 'plugin_name',
        //     'value' => $this->paystack_api->plugin_name
        // ];

        $custom_data[] = [
        'display_name' => 'Plugin Name',
        'variable_name' => 'plugin_name',
        'value' => 'pstk-gravityforms'
        ];

        // Generate transaction reference
        $reference = uniqid("gf-{$entry['id']}-");

        // Updating lead's payment_status to Processing
        GFAPI::update_entry_property($entry['id'], 'payment_status', 'Processing');

        // Prepare transaction data
        $args = array(
        'email'        => $customer_info['email'],
        'currency'     => $currency,
        'amount'       => $this->get_amount_export($payment_amount, $currency),
        'reference'    => $reference,
        'callback_url' => $return_url,
        'description'  => sprintf(__('%s (transaction: %s)', 'paystack'), $feed['meta']['feedName'], $reference),
        'metadata'     => array(
        'entry_id'    => $entry['id'],
        'site_url'    => esc_url(get_site_url()),
        'ip_address'  => $_SERVER['REMOTE_ADDR'],
        'custom_fields' => $custom_data
        )
        );

        if ($is_product) {
            $line_items     = rgar($submission_data, 'line_items');
            $discounts      = rgar($submission_data, 'discounts');

            // Create a Payment Request & Send Invoice
        }

        if ($is_subscription) {
            $plan = $this->create_plan($feed, $payment_amount, $currency);

            if (is_wp_error($plan)) {
                return false;
            }

            $args['plan'] = $plan['plan_code'];

            $submitted_recurring_times = rgar($submission_data, 'recurring_times');
            $invoice_limit = !empty($submitted_recurring_times) && $submitted_recurring_times !== '1' ? $submitted_recurring_times : null;

            if (!empty($invoice_limit) || $invoice_limit !== 'Infinite') {
                $args['invoice_limit'] = (int) $invoice_limit;
            }

            $args['channels'] = ['card'];

            gform_update_meta($entry['id'], 'paystack_plan_code', $plan['plan_code']);
        }

        // Initialize the charge on Paystack's servers - this will be used to charge the user's card
        $response = (object) $this->paystack_api->send_request("transaction/initialize/", $args);

        $this->log_debug(__METHOD__ . "(): Initialize Paystack Transaction. Reference: " . rgar($args, 'reference') . ', status: ' . (int) $response->status);

        if (!$response->status) {
            return false;
        }

        gform_update_meta($entry['id'], 'paystack_tx_reference', $response->data['reference']);
        gform_update_meta($entry['id'], 'paystack_mode', $mode);
        gform_update_meta($entry['id'], 'paystack_tx_amount', $args['amount']);
        gform_update_meta($entry['id'], 'paystack_tx_currency', $currency);
        gform_update_meta($entry['id'], 'paystack_tx_access_code', $response->data['access_code']);
        gform_update_meta($entry['id'], 'paystack_tx_auth_url', $response->data['authorization_url']);

        $this->log_debug(__METHOD__ . "(): Sending to Paystack: {$response->data['authorization_url']}");

        return  $response->data['authorization_url'];
    }

    public function get_fields_meta_data($feed, $entry, $fields)
    {
        $data = [];

        foreach ($fields as $field) {
            $field_id = $feed['meta'][$field['meta_name']];
            $value    = rgar($entry, $field_id);

            if ($field['name'] == 'country') {
                $value = class_exists('GF_Field_Address') ? GF_Fields::get('address')->get_country_code($value) : GFCommon::get_country_code($value);
            } elseif ($field['name'] == 'state') {
                $value = class_exists('GF_Field_Address') ? GF_Fields::get('address')->get_us_state_code($value) : GFCommon::get_us_state_code($value);
            }

            if (!empty($value)) {
                $data["{$field['name']}"] = $value;
            }
        }

        return $data;
    }

    public function get_customer_fields()
    {
        return array(
        array('name' => 'email', 'label' => 'Email', 'meta_name' => 'customerInformation_email'),
        array('name' => 'first_name', 'label' => 'First Name', 'meta_name' => 'customerInformation_firstName'),
        array('name' => 'last_name', 'label' => 'Last Name', 'meta_name' => 'customerInformation_lastName'),
        );
    }

    public function get_billing_fields()
    {
        return array(
        array('name' => 'address1', 'label' => 'Address', 'meta_name' => 'billingInformation_address'),
        array('name' => 'address2', 'label' => 'Address 2', 'meta_name' => 'billingInformation_address2'),
        array('name' => 'city', 'label' => 'City', 'meta_name' => 'billingInformation_city'),
        array('name' => 'state', 'label' => 'State', 'meta_name' => 'billingInformation_state'),
        array('name' => 'zip', 'label' => 'Zip', 'meta_name' => 'billingInformation_zip'),
        array('name' => 'country', 'label' => 'Country', 'meta_name' => 'billingInformation_country'),
        );
    }

    /**
     * Handle cancelling the subscription from the entry detail page.
     *
     * @param array $entry The entry object currently being processed.
     * @param array $feed  The feed object currently being processed.
     *
     * @return bool True if successful. False if failed.
     */
    public function cancel($entry, $feed)
    {
        // Getting mode (Live (Production) or Test (Sandbox))
        $mode = $feed['meta']['mode'];

        // Setup the Paystack API
        $this->paystack_api($mode);

        if (empty($entry['transaction_id'])) {
            return false;
        }

        // Get Paystack subscription object.
        $subscription = $this->get_subscription($entry['transaction_id']);

        if (!$subscription['status']) {
            return false;
        }

        if ($subscription['data']['status'] !== 'active') {
            $this->log_debug(__METHOD__ . '(): Subscription already cancelled.');

            return true;
        }

        try {
            $this->paystack_api->send_request(
                'subscription/disable', [
                'code'  => $entry['transaction_id'],
                'token' => gform_get_meta($entry['id'], 'paystack_email_token') //email token,
                ]
            );

            $this->log_debug(__METHOD__ . '(): Subscription cancelled.');

            return true;
        } catch (\Exception $e) {
            // Log error.
            $this->log_error(sprintf('%s(): Unable to cancel subscription; %s', __METHOD__, $e->getMessage()));

            return false;
        }
    }

    /**
     * Display the thank you page when there's a gf_paystack_return URL param and the charge is successful.
     *
     * @since 1.0
     */
    public function maybe_thankyou_page()
    {
        if (!$this->is_gravityforms_supported()) {
            return;
        }

        if ($str = sanitize_text_field(rgget('gf_paystack_return'))) {
            $str = base64_decode($str);

            $this->log_debug(__METHOD__ . '(): Return callback request received. Starting to process.');

            parse_str($str, $query);

            if (isset($query['ids'], $query['hash']) && is_string($query['ids']) && is_string($query['hash']) && hash_equals(wp_hash('ids=' . $query['ids']), $query['hash'])) {
                list($entry_id, $feed_id, $form_id) = explode('|', $query['ids']);

                $entry = GFAPI::get_entry($entry_id);
                $form = GFAPI::get_form($form_id);

                if (is_wp_error($entry) || !$entry) {
                    $this->log_error(__METHOD__ . '(): Entry could not be found. Aborting.');

                    return false;
                }

                $this->log_debug(__METHOD__ . '(): Entry has been found => ' . print_r($entry, true));

                if ($entry['status'] == 'spam') {
                    $this->log_error(__METHOD__ . '(): Entry is marked as spam. Aborting.');

                    return false;
                }

                // Get feed
                $feed = $this->get_feed($feed_id);

                $this->log_debug(__METHOD__ . "(): Form {$entry['form_id']} is properly configured.");

                // Let's ignore forms that are no longer configured to use the Paystack add-on  
                if (!$feed || !rgar($feed, 'is_active')) {
                    $this->log_error(__METHOD__ . "(): Form no longer uses the Paystack Addon. Form ID: {$entry['form_id']}. Aborting.");

                    return false;
                }

                // Getting mode Live (Production) or Test (Sandbox)
                $this->paystack_api($this->get_entry_mode($entry_id, $feed));

                $reference = sanitize_text_field(rgget('reference'));

                if (!self::reference_matches_entry(gform_get_meta($entry_id, 'paystack_tx_reference'), $reference)) {
                    $this->log_error(__METHOD__ . '(): Return request could not be matched to entry. Aborting.');

                    return false;
                }

                try {
                    $response = $this->paystack_api->verify_transaction($reference);

                    $this->log_debug(__METHOD__ . "(): Transaction verified. Reference: {$reference}, status: " . rgars($response, 'data/status'));
                } catch (\Exception $e) {
                    $this->log_error(__METHOD__ . "(): Transaction could not be verified. Reason: " . $e->getMessage());

                    return new WP_Error('transaction_verification', $e->getMessage());
                }

                $charge = $response['data'];

                if (!$response || $charge['status'] !== 'success') {
                    // Charge Failed
                    $this->log_error(__METHOD__ . "(): Transaction verification failed Reason: " . rgar($response, 'message'));

                    return false;
                }

                if (!self::charge_matches_stored(rgar($charge, 'amount'), rgar($charge, 'currency'), gform_get_meta($entry_id, 'paystack_tx_amount'), gform_get_meta($entry_id, 'paystack_tx_currency'))) {
                    $this->log_error(__METHOD__ . '(): Transaction amount or currency does not match the entry. Aborting.');

                    return false;
                }

                // Log Payment successful payment from this addon to paystack
                $this->paystack_api->log_transaction_success($reference);

                if (!class_exists('GFFormDisplay')) {
                    include_once GFCommon::get_base_path() . '/form_display.php';
                }

                $confirmation = GFFormDisplay::handle_confirmation($form, $entry, false);

                if (is_array($confirmation) && isset($confirmation['redirect'])) {
                    header("Location: {$confirmation['redirect']}");
                    exit;
                }

                GFFormDisplay::$submission[$form_id] = array(
                'is_confirmation'      => true,
                'confirmation_message' => $confirmation,
                'form'                 => $form,
                'lead'                 => $entry,
                );
            }
        }
    }

    // # WEBHOOKS ------------------------------------------------------------------------------------------------------

    /**
     * If the Paystack callback or webhook belongs to a valid entry process the raw response into a standard Gravity Forms $action.
     *
     * @access public
     *
     * @uses GFAddOn::get_plugin_settings()
     * @uses GFPaystack::get_api_mode()
     * @uses GFAddOn::log_error()
     * @uses GFAddOn::log_debug()
     * @uses GFPaymentAddOn::get_entry_by_transaction_id()
     * @uses GFPaymentAddOn::get_amount_import()
     * @uses GFPaystack::get_subscription_line_item()
     * @uses GFPaystack::get_captured_payment_note()
     * @uses GFAPI::get_entry()
     * @uses GFCommon::to_money()
     *
     * @return array|bool|WP_Error Return a valid GF $action or if the webhook can't be processed a WP_Error object or false.
     */
    public function callback()
    {
        if (!$this->is_gravityforms_supported()) {
            return;
        }

        $action = array();

        $event = $this->get_webhook_event();

        if (!$event || is_wp_error($event)) {
            return $event;
        }

        $this->log_debug(__METHOD__ . '(): Webhook callback received. Starting to process => ' . print_r($_REQUEST, true));

        // Get event type.
        $type = $event['event'];

        switch ($type) {
        case 'charge.success':
            if (!isset($event['data']['id']) || isset($event['data']['metadata']['invoice_action'])) {
                return false;
            }

            $reference = rgars($event, 'data/reference');
            $entry_id = $this->get_entry_id_by_reference($reference);

            if (!$entry_id) {
                return new WP_Error('entry_not_found', sprintf(__('Entry for transaction reference: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), is_scalar($reference) ? $reference : ''));
            }

            $metadata_entry_id = rgars($event, 'data/metadata/entry_id');

            if ($metadata_entry_id && (string) $metadata_entry_id !== (string) $entry_id) {
                $this->log_error(__METHOD__ . '(): Webhook could not be matched to entry. Aborting.');

                return false;
            }

            $entry = GFAPI::get_entry($entry_id);

            if (is_wp_error($entry)) {
                $this->log_error(__METHOD__ . '(): ' . $entry->get_error_message());

                return false;
            }

            $this->log_debug(__METHOD__ . '(): Entry has been found => ' . print_r($entry, true));

            $feed = $this->get_payment_feed($entry);

            // Let's ignore forms that are no longer configured to use the Paystack add-on  
            if (!$feed || !rgar($feed, 'is_active')) {
                $this->log_error(__METHOD__ . "(): Form no longer uses the Paystack Addon. Form ID: {$entry['form_id']}. Aborting.");

                return false;
            }

            if (!$this->webhook_mode_matches_entry($entry, $feed)) {
                return false;
            }

            if ($feed['meta']['transactionType'] == 'subscription') {
                gform_update_meta($entry_id, 'paystack_tx_auth_code', rgars($event, 'data/authorization/authorization_code'));
            } else {
                if (!self::charge_matches_stored(rgars($event, 'data/amount'), rgars($event, 'data/currency'), gform_get_meta($entry_id, 'paystack_tx_amount'), gform_get_meta($entry_id, 'paystack_tx_currency'))) {
                    $this->log_error(__METHOD__ . '(): Webhook could not be matched to entry. Aborting.');

                    return false;
                }

                $action['id']               = rgars($event, 'data/id') . '_' . $type;
                $action['entry_id']         = $entry_id;
                $action['transaction_id']   = rgars($event, 'data/id');
                $action['amount']           = $this->get_amount_import(rgars($event, 'data/amount'), rgars($event, 'data/currency'));
                $action['type']             = 'complete_payment';
                $action['ready_to_fulfill'] = !$entry['is_fulfilled'] ? true : false;
                $action['payment_date']     = rgars($event, 'data/paidAt');
                $action['payment_method']   = $this->_slug;
            }

            break;
        case 'subscription.create':
            $action['subscription_id'] = rgars($event, 'data/subscription_code');
            $entry_id = false;

            try {
                $subscription = $this->get_subscription($action['subscription_id']);

                $this->log_debug(__METHOD__ . "(): Subscription details retrieved for " . $action['subscription_id'] . '.');
            } catch (\Exception $e) {
                $this->log_error(__METHOD__ . "(): Subscription details not found. Reason: " . $e->getMessage());

                return new WP_Error('subscription_not_found', sprintf(__('Details for subscription id: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), $action['subscription_id']));
            }

            if (is_array($subscription['data']['invoices']) && count($subscription['data']['invoices']) >= 1) {
                $transaction = $subscription['data']['invoices'][0];

                $this->log_debug(__METHOD__ . "(): Initial transaction. Reference: " . rgar($transaction, 'reference') . ', status: ' . rgar($transaction, 'status') . ', amount: ' . rgar($transaction, 'amount'));

                $entry_id = $transaction['status'] == 'success' ? $this->get_entry_id_by_reference($transaction['reference']) : false;
            }

            if (!$entry_id) {
                return new WP_Error('entry_not_found', sprintf(__('Entry for subscription id: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), $action['subscription_id']));
            }

            $entry = $this->get_webhook_entry($entry_id);

            if (!$entry) {
                return false;
            }

            gform_update_meta($entry_id, 'paystack_email_token', rgars($event, 'data/email_token'));

            $action['id']                = $action['subscription_id'] . '_' . $type;
            $action['entry_id']         = $entry_id;
            $action['type']                = 'create_subscription';
            $action['amount']            = $this->get_amount_import(rgars($event, 'data/amount'), rgar($entry, 'currency'));
            $action['payment_method']    = $this->_slug;
            $action['ready_to_fulfill'] = !$entry['is_fulfilled'] ? true : false;

            $action['add_subscription_payment'] = [
            'entry_id'        => $entry_id,
            'subscription_id' => rgars($subscription, 'data/subscription_code'),
            'transaction_id'  => rgar($transaction, 'id'),
            'amount'          => $this->get_amount_import(rgar($transaction, 'amount'), rgar($entry, 'currency')),
            'payment_method'  => $this->_slug
            ];

            break;
        case 'subscription.disable':
            $action['subscription_id'] = rgars($event, 'data/subscription_code');

            $entry_id = $this->get_entry_by_transaction_id($action['subscription_id']);

            if (!$entry_id) {
                return new WP_Error('entry_not_found', sprintf(__('Entry for subscription id: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), $action['subscription_id']));
            }

            $entry = $this->get_webhook_entry($entry_id);

            if (!$entry) {
                return false;
            }

            if ($entry['payment_status'] == 'Cancelled' || $entry['payment_status'] == 'Expired') {
                $this->log_error(__METHOD__ . '(): Subscription for entry ' . $entry['id'] . ' is no longer Active');

                return false;
            }

            $action['entry_id'] = $entry_id;

            try {
                $subscription = $this->get_subscription($action['subscription_id']);

                $paid_invoices = 0;

                if (is_array($subscription['data']['invoices']) && $invoices = $subscription['data']['invoices']) {
                    $this->log_debug(__METHOD__ . '(): Subscription invoices: ' . count($invoices));

                    foreach ($invoices as $invoice) {
                        if ($invoice['status'] == 'success') {
                            $paid_invoices++;
                        }
                    }
                }

                $invoice_limit = (int) rgars($subscription, 'data/invoice_limit');

                if ($invoice_limit > 0 && $paid_invoices >= $invoice_limit) {
                    $action['type']  = 'expire_subscription';
                } else {
                    $action['type']  = 'cancel_subscription';
                }
            } catch (\Exception $e) {
                $this->log_error(__METHOD__ . "(): Paystack Subscription details not found. Reason: " . $e->getMessage() . 'So we cancel the subscrption.');

                $action['type']  = 'cancel_subscription';

                // return new WP_Error('subscription_not_found', sprintf(__('Details for subscription id: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), $action['subscription_id']));
            }

            break;

        case 'invoice.create':
        case 'invoice.update':
            $action['subscription_id'] = rgars($event, 'data/subscription/subscription_code');

            $entry_id  = $this->get_entry_by_transaction_id($action['subscription_id']);

            if (!$entry_id) {
                return new WP_Error('entry_not_found', sprintf(__('Entry for subscription id: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), $action['subscription_id']));
            }

            $entry = $this->get_webhook_entry($entry_id);

            if (!$entry) {
                return false;
            }

            try {
                $subscription = $this->get_subscription($action['subscription_id']);
            } catch (\Exception $e) {
                $this->log_error(__METHOD__ . "(): Subscription details not found. Reason: " . $e->getMessage());

                return new WP_Error('subscription_not_found', sprintf(__('Details for subscription id: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), $action['subscription_id']));
            }

            $reference = rgars($event, 'data/transaction/reference');

            if (!is_string($reference) || $reference === '') {
                return false;
            }

            $invoices = rgars($subscription, 'data/invoices');
            $transaction = null;

            if (is_array($invoices)) {
                foreach ($invoices as $inv) {
                    if (rgar($inv, 'reference') === $reference) {
                        $transaction = $inv;
                        break;
                    }
                }
            }

            if ($transaction !== null) {
                $is_paid = rgar($transaction, 'status') === 'success' || !empty($transaction['paid']);
            } else {
                try {
                    $response = $this->paystack_api->verify_transaction($reference);
                } catch (\Exception $e) {
                    $this->log_error(__METHOD__ . "(): Transaction could not be verified. Reason: " . $e->getMessage());

                    return new WP_Error('transaction_verification', $e->getMessage());
                }

                $transaction = rgar($response, 'data');
                $customer = rgars($subscription, 'data/customer/customer_code');

                if (!$customer || rgars($transaction, 'customer/customer_code') !== $customer) {
                    $this->log_error(__METHOD__ . '(): Invoice transaction could not be matched to subscription. Aborting.');

                    return false;
                }

                $is_paid = rgar($transaction, 'status') === 'success';
            }

            $this->log_debug(__METHOD__ . '(): Invoice transaction. Reference: ' . $reference . ', status: ' . rgar($transaction, 'status') . ', amount: ' . rgar($transaction, 'amount'));

            if (!$is_paid) {
                $this->log_debug(__METHOD__ . '(): Transaction is not successful; no payment recorded.');

                return false;
            }

            $action['id']               = rgar($transaction, 'id') . '_' . $type;
            $action['type']             = 'add_subscription_payment';
            $action['subscription_id']  = rgar($entry, 'transaction_id');
            $action['transaction_id']   = rgars($transaction, 'id');
            $action['amount']           = $this->get_amount_import(rgar($transaction, 'amount'), rgar($entry, 'currency'));
            $action['entry_id']         = $entry_id;
            $action['payment_method']    = $this->_slug;

            break;

        case 'invoice.payment_failed':
            $action['subscription_id'] = rgars($event, 'data/subscription/subscription_code');

            //no transaction created
            $action['id'] = $action['subscription_id'] . '_' . rgars($event, 'data/invoice_code') . '_' . $type;

            $entry_id  = $this->get_entry_by_transaction_id($action['subscription_id']);

            if (!$entry_id) {
                return new WP_Error('entry_not_found', sprintf(__('Entry for subscription id: %s was not found. Webhook cannot be processed.', 'gravityformspaystack'), $action['subscription_id']));
            }

            $entry = $this->get_webhook_entry($entry_id);

            if (!$entry) {
                return false;
            }

            $action['type']      = 'fail_subscription_payment';
            $action['entry_id']  = $entry['id'];
            $action['amount']    = $this->get_amount_import(rgars($event, 'data/amount'), rgar($entry, 'currency'));
            $action['payment_method']    = $this->_slug;

            break;
        }

        if (rgempty('entry_id', $action)) {
            $this->log_debug(__METHOD__ . '() entry_id not set for callback action; no further processing required.');

            return false;
        }

        return $action;
    }

    /**
     * Helper for making the gform_post_payment_action hook available to the various payment interaction methods. Also handles sending notifications for payment events.
     *
     * @param array $entry
     * @param array $action
     */
    public function post_payment_action($entry, $action)
    {
        parent::post_payment_action($entry, $action);

        if (isset($action['add_subscription_payment']) && is_array($action['add_subscription_payment'])) {
            $this->add_subscription_payment($entry, $action['add_subscription_payment']);
        }
    }

    /**
     * Only `live` and `test` are accepted; anything else resolves to null.
     *
     * @param mixed $raw
     *
     * @return string|null
     */
    public static function resolve_webhook_mode($raw)
    {
        return in_array($raw, array('live', 'test'), true) ? $raw : null;
    }

    public static function reference_matches_entry($stored, $given)
    {
        return is_string($stored) && is_string($given) && $stored !== '' && hash_equals($stored, $given);
    }

    public static function modes_match($event_mode, $feed_mode)
    {
        return is_string($event_mode) && $event_mode !== '' && $event_mode === $feed_mode;
    }

    /**
     * An event amount above the stored amount is accepted, as customers may bear Paystack fees.
     *
     * @param mixed $event_amount
     * @param mixed $event_currency
     * @param mixed $stored_amount
     * @param mixed $stored_currency
     *
     * @return bool
     */
    public static function charge_matches_stored($event_amount, $event_currency, $stored_amount, $stored_currency)
    {
        if ((string) $stored_amount === '') {
            return true;
        }

        if (!is_numeric($event_amount) || !is_numeric($stored_amount) || (int) $event_amount < (int) $stored_amount) {
            return false;
        }

        if ((string) $stored_currency !== '') {
            return strtoupper((string) $event_currency) === strtoupper((string) $stored_currency);
        }

        return true;
    }

    /**
     * @param int|string $entry_id
     * @param array|bool $feed
     *
     * @return string
     */
    protected function get_entry_mode($entry_id, $feed = null)
    {
        return gform_get_meta($entry_id, 'paystack_mode') ?: rgars($feed, 'meta/mode');
    }

    /**
     * Load an entry for a webhook, only if it belongs to the mode the event was sent for.
     *
     * @param int|string $entry_id
     * @param array|bool $feed
     *
     * @return array|false
     */
    protected function get_webhook_entry($entry_id, $feed = null)
    {
        $entry = GFAPI::get_entry($entry_id);

        if (is_wp_error($entry)) {
            $this->log_error(__METHOD__ . '(): ' . $entry->get_error_message());

            return false;
        }

        if (!$this->webhook_mode_matches_entry($entry, $feed)) {
            return false;
        }

        return $entry;
    }

    /**
     * Entries without a stored mode fall back to the feed mode, then to the global mode; the global fallback only accepts live events.
     *
     * @param array      $entry
     * @param array|bool $feed
     *
     * @return bool
     */
    protected function webhook_mode_matches_entry($entry, $feed = null)
    {
        $expected = $this->get_entry_mode(rgar($entry, 'id'), $feed);

        if (empty($expected) && !$feed) {
            $expected = rgars($this->get_payment_feed($entry), 'meta/mode');
        }

        if (empty($expected)) {
            $global_mode = $this->get_api_mode($this->get_plugin_settings());
            $expected = $global_mode === 'live' ? 'live' : '';
        }

        if (!self::modes_match($this->webhook_mode, $expected)) {
            $this->log_error(__METHOD__ . '(): Webhook could not be matched to entry. Aborting.');

            return false;
        }

        return true;
    }

    /**
     * Retrieve the Paystack Event for the received webhook.
     *
     * @return false|WP_Error
     */
    public function get_webhook_event($body = null)
    {
        if ($body === null) {
            $body = @file_get_contents('php://input');
        }

        $response = json_decode($body, true);

        $settings = $this->get_plugin_settings();

        // Get api mode from data
        $mode = self::resolve_webhook_mode(rgars($response, 'data/domain')) ?: $this->get_api_mode($settings);

        $this->paystack_api($mode, $settings);

        $this->webhook_mode = $mode;

        // Validate Webhook Request Payload
        try {
            $is_verified = $this->paystack_api->validate_webhook($body);
        } catch (\Exception $e) {
            $this->log_error(__METHOD__ . "(): Error: " . $e->getMessage());

            return new WP_Error('Webhook Validation Failed', $e->getMessage());
        }

        if (!$is_verified) {
            $this->log_error(__METHOD__ . '(): Wehhook request is invalid. Aborting.');

            return false;
        }

        $this->log_debug(__METHOD__ . "(): Processing {$this->webhook_mode} mode event.");

        return $response;
    }

    /**
     * Generate the url Paystack webhooks should be sent to.
     *
     * @access public
     *
     * @used-by GFPaystack::get_webhooks_section_description()
     *
     * @param int $feed_id The feed id.
     *
     * @return string The webhook URL.
     */
    public function get_webhook_url($feed_id = null)
    {
        $url = home_url('/', 'https') . '?callback=' . $this->_slug;

        if (!rgblank($feed_id)) {
            $url .= '&fid=' . $feed_id;
        }

        return $url;
    }

    /**
     * Helper to check that webhooks are enabled.
     *
     * @access public
     *
     * @used-by GFPaystack::can_create_feed()
     * @uses    GFAddOn::get_plugin_setting()
     *
     * @return bool True if webhook is enabled. False otherwise.
     */
    public function is_webhook_enabled()
    {
        return $this->get_plugin_setting('webhooks_enabled') == true;
    }

    // # PAYSTACK HELPER FUNCTIONS ---------------------------------------------------------------------------------------

    /**
     * Try and retrieve the plan if a plan with the matching id has previously been created.
     *
     * @access public
     *
     * @param string $plan_id The subscription plan id or code.
     *
     * @return array|bool|string $plan The plan details. False if not found. If invalid request, the error message.
     */
    public function get_plan($plan_id_or_code)
    {
        // Get Paystack plan.
        $response = (object) $this->paystack_api->send_request("plan/{$plan_id_or_code}", [], 'get');

        $plan = $response->data;

        return $plan;
    }

    /**
     * Create and return a Paystack plan with the specified properties.
     *
     * @access public
     *
     * @uses GFPaymentAddOn::get_amount_export()
     * @uses GFAddOn::log_debug()
     *
     * @param array     $feed              The feed currently being processed.
     * @param float|int $payment_amount    The recurring amount.
     * @param int       $trial_period_days The number of days the trial should last.
     * @param string    $currency          The currency code for the entry being processed.
     *
     * @return array The plan object.
     */
    public function create_plan($feed, $payment_amount, $currency)
    {
        // Prepare plan data.
        $billing_cycle = rgar($feed['meta'], 'billingCycle_unit');

        $name = $this->get_plan_name($feed, $billing_cycle, $payment_amount, $currency);
        $amount = $this->get_amount_export($payment_amount, $currency);

        $recurring_times = (int) rgar($feed['meta'], 'recurringTimes');
        $send_invoices = (int) rgar($feed['meta'], 'sendInvoices') == 1 ? 'true' : 'false';

        $args = array(
        'name'            => $name,
        'currency'        => $currency,
        'amount'          => $amount,
        'interval'        => $billing_cycle,
        'invoice_limit'   => $recurring_times,
        'send_invoices'   => $send_invoices
        );

        // Log the plan to be created.
        $this->log_debug(__METHOD__ . '(): Plan to be created => ' . print_r($args, true));

        // Create Paystack plan.
        try {
            $response = (object) $this->paystack_api->send_request('plan', $args);
        } catch (\Exception $e) {
            // Get error response.
            $this->log_debug(__METHOD__ . '(): Unable to create Plan. Reason: ' . $e->getMessage());

            return new WP_Error('plan_not_created', $e->getMessage());
        }

        $this->log_debug(__METHOD__ . "(): Plan Created. " . print_r($response, true));

        return $response->data;
    }

    public function get_plan_name($feed, $billing_cycle, $payment_amount, $currency = '')
    {
        $get_name = rgars($feed, 'meta/planName') ?? $feed['meta']['feedName'];

        $plan_name = implode('_', array_filter(array($get_name, $feed['id'], $billing_cycle, $payment_amount, $currency)));

        return $plan_name;
    }

    /**
     * Gets the Paystack subscription object for the given ID.
     *
     * @param string $subscription_id The subscription ID.
     *
     * @return bool|array
     */
    public function get_subscription($subscription_id_or_code)
    {
        $this->log_debug(__METHOD__ . '(): Getting subscription ' . $subscription_id_or_code);

        try {
            $subscription = $this->paystack_api->send_request("subscription/{$subscription_id_or_code}", [], 'get');
        } catch (\Exception $e) {
            $this->log_error(__METHOD__ . '(): Unable to get subscription. Reason: ' . $e->getMessage());

            $subscription = false;
        }

        return $subscription;
    }

    /**
     * If custom meta data has been configured on the feed retrieve the mapped field values.
     *
     * @access public
     *
     * @uses GFAddOn::get_field_value()
     *
     * @param array $feed  The feed object currently being processed.
     * @param array $entry The entry object currently being processed.
     * @param array $form  The form object currently being processed.
     *
     * @return array The Paystack meta data.
     */
    public function get_paystack_meta_data($feed, $entry, $form)
    {
        // Initialize metadata array.
        $metadata = array();

        // Find feed metadata.
        $custom_meta = rgars($feed, 'meta/metaData');

        if (is_array($custom_meta)) {
            // Loop through custom meta and add to metadata for paystack.
            foreach ($custom_meta as $meta) {

                // If custom key or value are empty, skip meta.
                if (empty($meta['custom_key']) || empty($meta['value'])) {
                    continue;
                }

                // Make the key available to the gform_paystack_field_value filter.
                $this->_current_meta_key = $meta['custom_key'];

                // Get field value for meta key.
                $field_value = $this->get_field_value($form, $entry, $meta['value']);

                if (!empty($field_value)) {
                    // Trim to 500 characters.
                    $field_value = substr($field_value, 0, 500);

                    // Add to metadata array.
                    $metadata[] = [
                    'display_name' => $meta['custom_key'],
                    'variable_name' => sanitize_title($meta['custom_key']),
                    'value' => $field_value,
                    ];
                }
            }

            // Clear the key in case get_field_value() and gform_paystack_field_value are used elsewhere.
            $this->_current_meta_key = '';
        }

        return $metadata;
    }

    /**
     * Initialize the Paystack API and returns the GF Paysack API Object.
     *
     * @access public
     *
     * @used-by GFPaystack::cancel()
     * @used-by GFPaystack::get_paystack_event()
     * @used-by GFPaystack::subscribe()
     * @uses    GFAddOn::get_base_path()
     * @uses    GFPaystack::get_secret_api_key()
     * @uses    GFPaystack::get_public_api_key()
     * 
     * @param null|string $mode     The API mode; live or test.
     * @param null|array  $settings The settings.
     * 
     * @return \GFPaystackApi
     */
    public function paystack_api($mode = null, $settings = null)
    {
        if (empty($settings)) {
            $settings = $this->get_plugin_settings();
        }

        if (empty($mode)) {
            $mode  = $this->get_api_mode($settings);
        }

        $config = (object) array(
        'secret_key' => $this->get_secret_api_key($mode, $settings),
        'public_key' => $this->get_public_api_key($mode, $settings)
        );

        $this->log_debug(sprintf('%s(): Initializing Paystack API for %s mode.', __METHOD__, $mode));

        return $this->paystack_api = new GFPaystackApi($config);
    }

    // # OTHER HELPER FUNCTIONS ----------------------------------------------------------------------------------------------

    /**
     * Retrieve the specified api key.
     *
     * @access public
     *
     * @used-by GFPaystack::get_public_api_key()
     * @used-by GFPaystack::get_secret_api_key()
     * @uses    GFPaystack::get_query_string_api_key()
     * @uses    GFAddOn::get_plugin_settings()
     * @uses    GFPaystack::get_api_mode()
     * @uses    GFAddOn::get_setting()
     *
     * @param string      $type     The type of key to retrieve.
     * @param null|string $mode     The API mode; live or test.
     * @param null|int    $settings The current settings.
     *
     * @return string
     */
    public function get_api_key($type = 'secret', $mode = null, $settings = null)
    {
        // Check for api key in query first; user must be an administrator to use this feature.
        $api_key = $this->get_query_string_api_key($type);
        if ($api_key && current_user_can('update_core')) {
            return $api_key;
        }

        if (!isset($settings)) {
            $settings = $this->get_plugin_settings();

            if (!$mode) {
                // Get API mode.
                $mode = $this->get_api_mode($settings);
            }
        }

        // Get API key based on current mode and defined type.
        $setting_key = "{$mode}_{$type}_key";
        $api_key     = $this->get_setting($setting_key, '', $settings);

        return $api_key;
    }

    /**
     * Helper to implement the gform_paystack_api_mode filter so the api mode can be overridden.
     *
     * @access public
     *
     * @used-by GFPaystack::get_api_key()
     * @used-by GFPaystack::callback()
     * @used-by GFPaystack::can_create_feed()
     *
     * @param array $settings The plugin settings.
     * @param int   $feed_id  Feed ID.
     *
     * @return string $api_mode Either live or test.
     */
    public function get_api_mode($settings, $feed_id = null)
    {
        // Get API mode from settings.
        $api_mode = rgar($settings, 'api_mode');

        /**
         * Filters the API mode.
         *
         * @param string $api_mode The API mode.
         * @param int    $feed_id  Feed ID.
         */
        return apply_filters('gform_paystack_api_mode', $api_mode, $feed_id);
    }

    /**
     * Retrieve the specified api key from the query string.
     *
     * @access public
     *
     * @used-by GFPaystack::get_api_key()
     *
     * @param string $type The type of key to retrieve. Defaults to 'secret'.
     *
     * @return string The result of the query string.
     */
    public function get_query_string_api_key($type)
    {
        return rgget($type);
    }

    /**
     * Retrieve the public api key.
     *
     * @access public
     *
     * @uses GFPaystack::get_api_key()
     *
     * @param null|string $mode     The API mode; live or test.
     * @param array|null  $settings The current settings.
     *
     * @return string The public API key.
     */
    public function get_public_api_key($mode = null, $settings = null)
    {
        if (empty($settings)) {
            $settings = $this->get_plugin_settings();
        }

        if (empty($mode)) {
            $mode = $this->get_api_mode($settings);
        }

        return $this->get_api_key('public', $mode, $settings);
    }

    /**
     * Retrieve the secret api key.
     *
     * @access public
     *
     * @uses GFPaystack::get_api_key()
     *
     * @param null|string $mode     The API mode; live or test.
     * @param null|array  $settings The current settings.
     *
     * @return string The secret API key.
     */
    public function get_secret_api_key($mode = null, $settings = null)
    {
        if (empty($settings)) {
            $settings = $this->get_plugin_settings();
        }

        if (empty($mode)) {
            $mode = $this->get_api_mode($settings);
        }

        return $this->get_api_key('secret', $mode, $settings);
    }

    /**
     * Adds the currency if it isn't already registered.
     *
     * @since   1.0
     * @access  public
     * @used-by gform_currencies
     * 
     * @param array $currencies The current currencies registered in Gravity Forms.
     *
     * @return array List of supported currencies.
     */
	public function add_paystack_currencies($currencies)
	{
		// Check if the currency is already registered.
		if (!array_key_exists('NGN', $currencies)) {
			// Add NGN to the list of supported currencies.
			$currencies['NGN'] = array(
				'name'               => 'Nigeria Naira',
				'symbol_left'        => '&#8358;',
				'symbol_right'       => '',
				'symbol_padding'     => ' ',
				'thousand_separator' => ',',
				'decimal_separator'  => '.',
				'decimals'           => 2,
				'code'               => 'NGN'
			);
		}
	
		// Check if the currency is already registered.
		if (!array_key_exists('GHS', $currencies)) {
			// Add GHS to the list of supported currencies.
			$currencies['GHS'] = array(
				'name'               => 'Ghana Cedis',
				'symbol_left'        => '&#8373;',
				'symbol_right'       => '',
				'symbol_padding'     => ' ',
				'thousand_separator' => ',',
				'decimal_separator'  => '.',
				'decimals'           => 2,
				'code'               => 'GHS'
			);
		}
	
		// Check if the currency is already registered.
		if (!array_key_exists('ZAR', $currencies)) {
			// Add ZAR to the list of supported currencies.
			$currencies['ZAR'] = array(
				'name'               => 'South Africa Rand',
				'symbol_left'        => 'R',
				'symbol_right'       => '',
				'symbol_padding'     => ' ',
				'thousand_separator' => ',',
				'decimal_separator'  => '.',
				'decimals'           => 2,
				'code'               => 'ZAR'
			);
		}
	
		// Check if the currency is already registered.
		if (!array_key_exists('KES', $currencies)) {
			// Add KES to the list of supported currencies.
			$currencies['KES'] = array(
				'name'               => 'Kenyan Shillings',
				'symbol_left'        => 'KSh',
				'symbol_right'       => '',
				'symbol_padding'     => ' ',
				'thousand_separator' => ',',
				'decimal_separator'  => '.',
				'decimals'           => 2,
				'code'               => 'KES'
			);
		}
	
		// Check if the currency is already registered.
		if (!array_key_exists('XOF', $currencies)) {
			// Add XOF to the list of supported currencies.
			$currencies['XOF'] = array(
				'name'               => 'West African CFA franc',
				'symbol_left'        => 'CFA',
				'symbol_right'       => '',
				'symbol_padding'     => ' ',
				'thousand_separator' => ',',
				'decimal_separator'  => '.',
				'decimals'           => 2,
				'code'               => 'XOF'
			);
		}
	
		// Check if the currency is already registered.
		if (!array_key_exists('EGP', $currencies)) {
			// Add EGP to the list of supported currencies.
			$currencies['EGP'] = array(
				'name'               => 'Egyptian Pound',
				'symbol_left'        => '£',
				'symbol_right'       => '',
				'symbol_padding'     => ' ',
				'thousand_separator' => ',',
				'decimal_separator'  => '.',
				'decimals'           => 2,
				'code'               => 'EGP'
			);
		}
	
		return $currencies;
	}

    /**
     * Check if rate limits is enabled.
     *
     * @param int $form_id The form ID.
     *
     * @return bool
     */
    public function is_rate_limits_enabled($form_id)
    {
        /**
         * Allow enabling or disable the rate limit check.
         *
         * @param bool $has_error The default is false.
         * @param int  $form_id   The form ID.
         */
        $this->_enable_rate_limits = apply_filters('gform_paystack_enable_rate_limits', $this->_enable_rate_limits, $form_id);

        return $this->_enable_rate_limits;
    }

    public function get_entry_id_by_reference($reference)
    {
        global $wpdb;

        if (!is_string($reference) || $reference === '') {
            return false;
        }

        $entry_meta_table_name = self::get_entry_meta_table_name();

        $sql = $wpdb->prepare("SELECT entry_id, meta_value FROM {$entry_meta_table_name} WHERE meta_key = 'paystack_tx_reference' AND meta_value = '%s'", $reference);
        $row = $wpdb->get_row($sql);

        if (!$row || !self::reference_matches_entry($row->meta_value, $reference)) {
            return false;
        }

        return $row->entry_id;
    }
}