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<?php
/**
 * Gravity Wiz // Gravity Forms // Field-specific Upload Path
 *
 * Provides a method for specifying field-specific file upload paths.
 *
 * @version	  1.0
 * @author    David Smith <david@gravitywiz.com>
 * @license   GPL-2.0+
 * @link      http://gravitywiz.com/...
 */
class GF_Field_Specific_File_Upload_Path {

    var $current_field = null;

    function __construct() {

        add_filter( 'gform_save_field_value', array( $this, 'stash_current_field_id' ), 10, 4 );
        add_filter( 'gform_upload_path', array( $this, 'modify_upload_path' ) );

    }

    /**
     * This is a little tricky... we get the $field that is about to be saved, but the field we want is whatever is next in the queue.
     * To do this, we'll simply search for the next file upload field based on the position of the current field.
     */
    function stash_current_field_id( $value, $entry, $current_field, $form ) {

        $is_next = false;
        $next_field = false;

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

            $is_file_upload = GFFormsModel::get_input_type( $field ) == 'fileupload';
            $is_current_field = $field['id'] == $current_field['id'];

            if( $is_next && $is_file_upload ) {
                $next_field = $field;
                break;
            } else if( $is_current_field ) {
                $is_next = true;
            }

        }

        $this->current_field = $next_field;

        return $value;
    }

    function modify_upload_path( $upload_path ) {

        // modify the upload path based on the current field ID:
        // $current_field_id = $this->current_field_id

        $applicable_forms_fields = array(
            array(
                'form_id' => 13,
                'folder_name' => rgpost( 'input_4' ),
                'field_ids' => array( 6, 15, 16 )
            ),
            array(
                'form_id' => 547,
                'folder_name' => rgpost( 'input_1' ),
                'field_ids' => array( 2 )
            ),
            array(
                'form_id' => 547,
                'folder_name' => rgpost( 'input_4' ),
                'field_ids' => array( 3 )
            )
        );

        foreach( $applicable_forms_fields as $forms_fields ) {

            $is_current_form = $this->current_field['formId'] == $forms_fields['form_id'];
            $has_current_field = in_array( $this->current_field['id'], $forms_fields['field_ids'] );

            if( $is_current_form && $has_current_field ) {
                $applicable_fields = $forms_fields['field_ids'];
                $folder_name = $forms_fields['folder_name'];
            }

        }

        if( ! isset( $applicable_fields ) || ! isset( $folder_name ) ) {
            return $upload_path;
        }

        $upload_path['path'] = "/Applications/MAMP/htdocs/localhost/wp-content/uploads/{$folder_name}/";
        $upload_path['url'] = "http://localhost/wp-content/uploads/{$folder_name}/";

        return $upload_path;
    }

}

new GF_Field_Specific_File_Upload_Path();