Gravity Wiz // Gravity Forms // Advanced Merge Tags

gw-gravity-forms-advanced-merge-tags.php

<?php
/**
 * WARNING! THIS SNIPPET MAY BE OUTDATED.
 * The latest version of this snippet can be found in the Gravity Wiz Snippet Library:
 * https://github.com/gravitywiz/snippet-library/blob/master/gravity-forms/gw-advanced-merge-tags.php
 */
/**
 * Gravity Wiz // Gravity Forms // Advanced Merge Tags
 *
 * Adds support for several advanced merge tags:
 *   + post:id=xx&prop=xxx
 *       retrieve the desired property of the specified post (by ID)
 *   + post_meta:id=xx&meta_key=xxx
 *       retrieve the desired post meta value from the specified post and meta key
 *   + get() modifier
 *       retrieve the desired property from the query string ($_GET)
 *       Example: post_meta:id=get(xx)&meta_key=xxx
 *   + post() modifier
 *       retrieve the enclosed property from the $_POST
 *       Example: post_meta:id=post(xx)&meta_key=xxx
 *   + get:xxx
 *      retrieve property from query string
 *   + HTML fields
 *      {HTML:3}
 *      {all_fields:allowHtmlFields}
 * 
 * Coming soon...
 *   + {Address:1}
 *        Output values from all Address inputs.
 *   + {Name:1}
 *        Output values from all Name inputs.
 *   + {Date:1:mdy}
 *        Format date field output: https://gist.github.com/spivurno/f1fb2f0f3650d63acfb5ed644296abda
 *
 * Use Cases
 *
 *   + You have a multiple realtors each represented by their own WordPress page. On each page is a "Contact this Realtor"
 *       link. The user clicks the link and is directed to a contact form. Rather than creating a host of different
 *       contact forms for each realtor, you can use this snippet to populate a HTML field with a bit of text like:
 *       "You are contacting realtor Bob Smith" except instead of Bob Smith, you would use "{post:id=pid&prop=post_title}.
 *       In this example, "pid" would be passed via the query string from the contact link and "Bob Smith" would be the
 *       "post_title" of the post the user is coming from.
 *
 * @version 1.2
 * @author  David Smith <david@gravitywiz.com>
 * @license GPL-2.0+
 * @link    https://gravitywiz.com/
 *
 * Plugin Name: Gravity Forms Advanced Merge Tags
 * Plugin URI: https://gravitywiz.com
 * Description: Provides a host of new ways to work with Gravity Forms merge tags.
 * Version: 1.1
 * Author: Gravity Wiz
 * Author URI: https://gravitywiz.com/
 */
class GW_Advanced_Merge_Tags {

    /**
    * @TODO:
    *   - add support for validating based on the merge tag (to prevent values from being changed)
    *   - add support for merge tags in dynamic population parameters
    *   - add merge tag builder
    */

    private $_args = null;

    public static $instance = null;

    public static function get_instance( $args ) {

        if( null == self::$instance )
            self::$instance = new self( $args );

        return self::$instance;
    }

    private function __construct( $args ) {

        if( ! class_exists( 'GFForms' ) )
            return;

        $this->_args = wp_parse_args( $args, array(
            'save_source_post_id' => false
        ) );

        add_action( 'gform_pre_render', array( $this, 'support_default_value_and_html_content_merge_tags' ) );
        add_action( 'gform_pre_render', array( $this, 'support_dynamic_population_merge_tags' ) );

        add_action( 'gform_merge_tag_filter',       array( $this, 'support_html_field_merge_tags' ), 10, 4 );
        add_action( 'gform_replace_merge_tags',     array( $this, 'replace_merge_tags' ), 10, 3 );
        add_action( 'gform_pre_replace_merge_tags', array( $this, 'replace_get_variables' ), 10, 5 );

        if( $this->_args['save_source_post_id'] ) {
            add_filter( 'gform_entry_created', array( $this, 'save_source_post_id' ), 10, 2 );
        }

    }

    public function support_default_value_and_html_content_merge_tags( $form ) {

        $current_page = max( 1, (int) rgars( GFFormDisplay::$submission, "{$form['id']}/page_number" ) );
        $fields = array();

        foreach( $form['fields'] as &$field ) {

//            $default_value = rgar( $field, 'defaultValue' );
//            preg_match_all( '/{.+}/', $default_value, $matches, PREG_SET_ORDER );
//            if( ! empty( $matches ) ) {
//                if( rgar( $field, 'pageNumber' ) != $current_page ) {
//                    $field['defaultValue'] = '';
//                } else {
//                    $field['defaultValue'] = $this->replace_merge_tags( $default_value, $form, null );
//                }
//            }

            // only run 'content' filter for fields on the current page
//            if( rgar( $field, 'pageNumber' ) != $current_page )
//                continue;
//
//            $html_content = rgar( $field, 'content' );
//            preg_match_all( '/{.+}/', $html_content, $matches, PREG_SET_ORDER );
//            if( ! empty( $matches ) )
//                $field['content'] = $this->replace_merge_tags( $html_content, $form, null );

        }

        return $form;
    }

    public function support_dynamic_population_merge_tags( $form ) {

        $filter_names = array();

        foreach($form['fields'] as &$field) {

            if(!rgar($field, 'allowsPrepopulate'))
                continue;

            // complex fields store inputName in the "name" property of the inputs array
            if(is_array(rgar($field, 'inputs')) && $field['type'] != 'checkbox') {
                foreach($field['inputs'] as $input) {
                    if(rgar($input, 'name'))
                        $filter_names[] = array('type' => $field['type'], 'name' => rgar($input, 'name'));
                }
            } else {
                $filter_names[] = array('type' => $field['type'], 'name' => rgar($field, 'inputName'));
            }

        }

        foreach($filter_names as $filter_name) {

            // do standard GF prepop replace first...
            $filtered_name = GFCommon::replace_variables_prepopulate($filter_name['name']);

            // if default prepop doesn't find anything, do our advanced replace
            if( $filter_name['name'] == $filtered_name )
                $filtered_name = $this->replace_merge_tags( $filter_name['name'], $form, null );

            if( $filter_name['name'] == $filtered_name )
                continue;

            add_filter("gform_field_value_{$filter_name['name']}", create_function("", "return '$filtered_name';"));
        }

        return $form;
    }

    public function replace_merge_tags( $text, $form, $entry ) {

	    // at some point GF started passing a pre-submission generated entry, it will have a null ID
        if( rgar( $entry, 'id' ) == null ) {
            $entry = null;
        }

	    // matches {Label:#fieldId#}
	    //         {Label:#fieldId#:#options#}
	    //         {Custom:#options#}
        while( preg_match_all( '/{(\w+)(:([\w&,=)(\-]+)){1,2}}/mi', $text, $matches, PREG_SET_ORDER ) ) {

            foreach( $matches as $match ) {

                list( $tag, $type, $args_match, $args_str ) = array_pad( $match, 4, false );
                parse_str( $args_str, $args );

                $args = array_map( array( $this, 'check_for_value_modifiers' ), $args );
                $value = '';

                switch( $type ) {
                    case 'post':
                        $value = $this->get_post_merge_tag_value( $args );
                        break;
                    case 'post_meta':
                    case 'custom_field':
                        $value = $this->get_post_meta_merge_tag_value( $args );
                        break;
                    case 'entry':
                        $args['entry'] = $entry;
                        $value = $this->get_entry_merge_tag_value( $args );
                        break;
                    case 'entry_meta':
                        $args['entry'] = $entry;
                        $value = $this->get_entry_meta_merge_tag_value( $args );
                        break;
                    case 'callback':
                        $args['callback'] = array_shift( array_keys( $args ) );
                        unset( $args[$args['callback']] );
                        $args['entry'] = $entry;
                        $value = $this->get_callback_merge_tag_value( $args );
                        break;
                }

                // @todo: figure out if/how to support values that are not strings
                if( is_array( $value ) || is_object( $value ) )
                    $value = '';

                $text = str_replace( $tag, $value, $text );

            }

        }

        return $text;
    }

    public function save_source_post_id( $entry, $form ) {

        if( is_singular() && ! rgget( 'gf_page' ) ) {
            $post_id = get_queried_object_id();
            gform_update_meta( $entry['id'], 'source_post_id', $post_id );
        }

    }

    public function check_for_value_modifiers( $text ) {

        // modifier regex (i.e. "get(value)")
        preg_match_all( '/([a-z]+)\(([a-z_\-]+)\)/mi', $text, $matches, PREG_SET_ORDER );
        if( empty( $matches ) )
            return $text;

        foreach( $matches as $match ) {

            list( $tag, $type, $arg ) = array_pad( $match, 3, false );
            $value = '';

            switch( $type ) {
            case 'get':
                $value = rgget( $arg );
                break;
            case 'post':
                $value = rgpost( $arg );
                break;
            }

            $text = str_replace( $tag, $value, $text );

        }

        return $text;
    }

    public function get_post_merge_tag_value( $args ) {

        extract( wp_parse_args( $args, array(
            'id' => false,
            'prop' => false
        ) ) );

        if( !$id || !$prop )
            return '';

        $post = get_post( $id );
        if( !$post )
            return '';

        return isset( $post->$prop ) ? $post->$prop : '';
    }

    public function get_post_meta_merge_tag_value( $args ) {

        extract( wp_parse_args( $args, array(
            'id' => false,
            'meta_key' => false
            ) ) );

        if( !$id || !$meta_key )
            return '';

        $value = get_post_meta( $id, $meta_key, true );

        return $value;
    }

    public function get_entry_merge_tag_value( $args ) {

        extract( wp_parse_args( $args, array(
            'id' => false,
            'prop' => false,
            'entry' => false
        ) ) );

	    if( ! $entry ) {

		    if( ! $id ) {
			    $id = rgget( 'eid' );
		    }

		    if( is_callable( 'gw_post_content_merge_tags' ) ) {
			    $id = gw_post_content_merge_tags()->maybe_decrypt_entry_id( $id );
		    }

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

	    }

        if( ! $prop ) {
	        $prop = key( $args );
        }

        if( ! $entry || is_wp_error( $entry ) || ! $prop ) {
	        return '';
        }

        $value = rgar( $entry, $prop );

        return $value;
    }

    public function get_entry_meta_merge_tag_value( $args ) {

        extract( wp_parse_args( $args, array(
            'id' => false,
            'meta_key' => false,
            'entry' => false
            ) ) );

        if( ! $id ) {
            if( rgget( 'eid' ) ) {
                $id = rgget( 'eid' );
            } else if( isset( $entry['id'] ) ) {
                $id = $entry['id'];
            }
        }

        if( ! $meta_key )
            $meta_key = key( $args );

        if( ! $id || ! $meta_key )
            return '';

        if( is_callable( 'gw_post_content_merge_tags' ) ) {
            $id = gw_post_content_merge_tags()->maybe_decrypt_entry_id( $id );
        }

        $value = gform_get_meta( $id, $meta_key );

        return $value;
    }

    public function get_callback_merge_tag_value( $args ) {

        $callback = $args['callback'];
        unset( $args['callback'] );

        extract( wp_parse_args( $args, array(
            'entry' => false
        ) ) );

        if( ! is_callable( $callback ) )
            return '';

        return call_user_func( $callback, $args );
    }

	/**
	 * Replace {get:xxx} merge tags. Thanks, Gravity View!
	 *
	 * @param       $text
	 * @param array $form
	 * @param array $entry
	 * @param bool  $url_encode
	 *
	 * @return mixed
	 */
    public function replace_get_variables( $text, $form, $entry, $url_encode, $esc_html, $get = null ) {

    	if( $get === null ) {
    		$get = $_GET;
	    }

		preg_match_all( "/{get:(.*?)}/ism", $text, $matches, PREG_SET_ORDER );
		if( empty( $matches ) ) {
			return $text;
		}

		foreach ( $matches as $match ) {

			list( $search, $property ) = $match;

			$value = stripslashes_deep( rgget( $property, $get ) );

			$glue  = gf_apply_filters( array( 'gpamt_get_glue', $property ), ', ', $property );
			$value = is_array( $value ) ? implode( $glue, $value ) : $value;
			$value = $url_encode ? urlencode( $value ) : $value;

			$esc_html = gf_apply_filters( array( 'gpamt_get_esc_html', $property ), $esc_html );
			$value    = $esc_html ? esc_html( $value ) : $value;

			$value = gf_apply_filters( array( 'gpamt_get_value', $property ), $value, $text, $form, $entry );

			$text = str_replace( $search, $value, $text );
		}

		return $text;
	}

	public function support_html_field_merge_tags( $value, $tag, $modifiers, $field ) {
    	if( $field->type == 'html' && ( $tag != 'all_fields' || in_array( 'allowHtmlFields', explode( ',', $modifiers ) ) ) ) {
    		$value = $field->content;
	    }
		return $value;
	}

}

function gw_advanced_merge_tags( $args = array() ) {
    return GW_Advanced_Merge_Tags::get_instance( $args );
}

gw_advanced_merge_tags( array(
    'save_source_post_id' => true
) );

👉 This Gist has been migrated to the Gravity Wiz Snippet Library:

https://github.com/gravitywiz/snippet-library/blob/master/gravity-forms/gw-advanced-merge-tags.php