<?php
/**
 * Form sources stored in their own database tables:
 * Ninja Forms, Gravity Forms, Formidable Forms and Fluent Forms.
 *
 * @package ALPEG\Forms
 */

namespace ALPEG\Forms\Admin;

use ALPEG\Forms\Fields;
use ALPEG\Forms\Files;

defined( 'ABSPATH' ) || exit;

/**
 * Reads the forms directly from the database. The source plugin does not have
 * to be active; nothing in its tables is changed.
 */
class Import_Sources {

	/**
	 * Supported sources: key => plugin name.
	 *
	 * @return string[]
	 */
	public static function names() {
		return array(
			'ninja'      => 'Ninja Forms',
			'gravity'    => 'Gravity Forms',
			'formidable' => 'Formidable Forms',
			'fluent'     => 'Fluent Forms',
		);
	}

	/**
	 * All forms of all table-based sources.
	 *
	 * @return array[]
	 */
	public static function find() {
		return array_merge( self::ninja(), self::gravity(), self::formidable(), self::fluent() );
	}

	/**
	 * Is there at least one form in one of the sources?
	 *
	 * @return bool
	 */
	public static function has_sources() {
		global $wpdb;
		$checks = array(
			'nf3_forms'          => 'SELECT id FROM %i LIMIT 1',
			'gf_form'            => 'SELECT id FROM %i WHERE is_trash = 0 LIMIT 1',
			'frm_forms'          => "SELECT id FROM %i WHERE is_template = 0 AND status <> 'trash' AND ( parent_form_id IS NULL OR parent_form_id = 0 ) LIMIT 1",
			'fluentform_forms'   => 'SELECT id FROM %i LIMIT 1',
		);
		foreach ( $checks as $table => $sql ) {
			$name = $wpdb->prefix . $table;
			if ( self::table_exists( $name ) && $wpdb->get_var( $wpdb->prepare( $sql, $name ) ) ) { // phpcs:ignore WordPress.DB
				return true;
			}
		}
		return false;
	}

	/* ------------------------------------------------------------------
	 * Ninja Forms 3
	 * ---------------------------------------------------------------- */

	/**
	 * Forms from Ninja Forms (tables nf3_forms, nf3_fields, nf3_field_meta, nf3_actions, nf3_action_meta).
	 *
	 * @return array[]
	 */
	public static function ninja() {
		global $wpdb;
		$forms_t = $wpdb->prefix . 'nf3_forms';
		$field_t = $wpdb->prefix . 'nf3_fields';
		if ( ! self::table_exists( $forms_t ) || ! self::table_exists( $field_t ) ) {
			return array();
		}
		$out   = array();
		$forms = $wpdb->get_results( $wpdb->prepare( 'SELECT * FROM %i ORDER BY id ASC', $forms_t ), ARRAY_A ); // phpcs:ignore WordPress.DB
		foreach ( (array) $forms as $form ) {
			$id      = (int) $form['id'];
			$rows    = $wpdb->get_results( $wpdb->prepare( 'SELECT * FROM %i WHERE parent_id = %d', $field_t, $id ), ARRAY_A ); // phpcs:ignore WordPress.DB
			$raw     = array();
			foreach ( (array) $rows as $row ) {
				$raw[] = array_merge( $row, self::ninja_meta( $wpdb->prefix . 'nf3_field_meta', (int) $row['id'] ) );
			}
			usort(
				$raw,
				static function ( $a, $b ) {
					return (int) ( isset( $a['order'] ) ? $a['order'] : 0 ) - (int) ( isset( $b['order'] ) ? $b['order'] : 0 );
				}
			);

			$map = array(
				'textbox'          => 'text',
				'firstname'        => 'text',
				'lastname'         => 'text',
				'address'          => 'text',
				'city'             => 'text',
				'zip'              => 'text',
				'email'            => 'email',
				'phone'            => 'tel',
				'textarea'         => 'textarea',
				'listselect'       => 'select',
				'listcountry'      => 'select',
				'liststate'        => 'select',
				'listradio'        => 'radio',
				'listcheckbox'     => 'checkbox',
				'listmultiselect'  => 'checkbox',
				'date'             => 'date',
				'number'           => 'number',
				'file_upload'      => 'file',
			);
			$ignore = array( 'hr', 'html', 'hidden', 'spam', 'recaptcha', 'recaptcha_v3', 'turnstile', 'note', 'confirm' );

			$fields  = array();
			$skipped = array();
			$ids     = array();
			$submit  = '';
			foreach ( $raw as $f ) {
				$type  = isset( $f['type'] ) ? (string) $f['type'] : '';
				$label = self::text( isset( $f['label'] ) ? $f['label'] : '' );
				if ( 'submit' === $type ) {
					$submit = $label;
					continue;
				}
				if ( 'checkbox' === $type ) {
					// A single checkbox: usually "I agree …" – take it over as consent if it is required.
					if ( ! empty( $f['required'] ) ) {
						$fields[] = self::field( 'consent', self::consent_label( $label ), true, $ids );
					} else {
						$fields[] = self::field( 'checkbox', $label, false, $ids, array( 'options' => array( '' !== $label ? $label : __( 'Yes', 'alpeg-forms' ) ) ) );
					}
					continue;
				}
				if ( ! isset( $map[ $type ] ) ) {
					if ( ! in_array( $type, $ignore, true ) ) {
						$skipped[] = $type . ( $label ? ' (' . $label . ')' : '' );
					}
					continue;
				}
				$extra = array(
					'placeholder' => self::text( isset( $f['placeholder'] ) ? $f['placeholder'] : '' ),
					'help'        => self::text( isset( $f['desc_text'] ) ? $f['desc_text'] : '' ),
				);
				$new   = $map[ $type ];
				if ( Fields::has_options( $new ) ) {
					$extra['options'] = self::option_labels( self::decode( isset( $f['options'] ) ? $f['options'] : array() ), array( 'label', 'value' ) );
					if ( ! $extra['options'] ) {
						$skipped[] = $type . ( $label ? ' (' . $label . ')' : '' );
						continue;
					}
				}
				if ( 'file' === $new ) {
					$extra['accept']     = 'both';
					$types               = self::text( isset( $f['upload_types'] ) ? $f['upload_types'] : '' );
					if ( '' !== $types ) {
						$extra['accept']     = 'custom';
						$extra['extensions'] = str_replace( array( '.', ',' ), array( '', ', ' ), $types );
					}
					$extra['max_size'] = isset( $f['max_file_size'] ) && (int) $f['max_file_size'] > 0 ? (int) $f['max_file_size'] : 5;
				}
				$fields[] = self::field( $new, $label, ! empty( $f['required'] ), $ids, $extra );
			}

			// Email and success message from the actions.
			$notify  = '';
			$subject = '';
			$success = '';
			$act_t   = $wpdb->prefix . 'nf3_actions';
			if ( self::table_exists( $act_t ) ) {
				$actions = $wpdb->get_results( $wpdb->prepare( 'SELECT id, type FROM %i WHERE parent_id = %d ORDER BY id ASC', $act_t, $id ), ARRAY_A ); // phpcs:ignore WordPress.DB
				foreach ( (array) $actions as $a ) {
					$meta = self::ninja_meta( $wpdb->prefix . 'nf3_action_meta', (int) $a['id'] );
					if ( 'email' === $a['type'] && '' === $notify ) {
						$to      = isset( $meta['to'] ) ? (string) $meta['to'] : '';
						$notify  = self::plain_address( $to );
						$subject = self::no_tags( isset( $meta['email_subject'] ) ? $meta['email_subject'] : '' );
					} elseif ( 'successmessage' === $a['type'] && '' === $success ) {
						$success = self::no_tags( isset( $meta['success_msg'] ) ? $meta['success_msg'] : '' );
					}
				}
			}
			$title = isset( $form['title'] ) && '' !== $form['title'] ? $form['title'] : ( isset( $form['form_title'] ) ? $form['form_title'] : '' );

			$out[] = Importer::result(
				'ninja',
				'Ninja Forms',
				$id,
				self::text( $title ),
				$fields,
				$skipped,
				array(
					'submitLabel'    => $submit,
					'notifyEmail'    => $notify,
					'notifySubject'  => $subject,
					'successMessage' => $success,
				)
			);
		}
		return $out;
	}

	/**
	 * Ninja Forms meta rows (key/value or meta_key/meta_value depending on version).
	 *
	 * @param string $table     Meta table.
	 * @param int    $parent_id Parent ID.
	 * @return array
	 */
	private static function ninja_meta( $table, $parent_id ) {
		global $wpdb;
		if ( ! self::table_exists( $table ) ) {
			return array();
		}
		$rows = $wpdb->get_results( $wpdb->prepare( 'SELECT * FROM %i WHERE parent_id = %d', $table, $parent_id ), ARRAY_A ); // phpcs:ignore WordPress.DB
		$out  = array();
		foreach ( (array) $rows as $r ) {
			$k = isset( $r['meta_key'] ) && '' !== (string) $r['meta_key'] ? $r['meta_key'] : ( isset( $r['key'] ) ? $r['key'] : '' );
			$v = isset( $r['meta_key'] ) && '' !== (string) $r['meta_key'] ? ( isset( $r['meta_value'] ) ? $r['meta_value'] : '' ) : ( isset( $r['value'] ) ? $r['value'] : '' );
			if ( '' !== (string) $k ) {
				$out[ $k ] = $v;
			}
		}
		return $out;
	}

	/* ------------------------------------------------------------------
	 * Gravity Forms
	 * ---------------------------------------------------------------- */

	/**
	 * Forms from Gravity Forms (tables gf_form and gf_form_meta).
	 *
	 * @return array[]
	 */
	public static function gravity() {
		global $wpdb;
		$forms_t = $wpdb->prefix . 'gf_form';
		$meta_t  = $wpdb->prefix . 'gf_form_meta';
		if ( ! self::table_exists( $forms_t ) || ! self::table_exists( $meta_t ) ) {
			return array();
		}
		$out   = array();
		$forms = $wpdb->get_results( $wpdb->prepare( 'SELECT id, title FROM %i WHERE is_trash = 0 ORDER BY id ASC', $forms_t ), ARRAY_A ); // phpcs:ignore WordPress.DB
		foreach ( (array) $forms as $form ) {
			$id   = (int) $form['id'];
			$meta = $wpdb->get_row( $wpdb->prepare( 'SELECT display_meta, confirmations, notifications FROM %i WHERE form_id = %d', $meta_t, $id ), ARRAY_A ); // phpcs:ignore WordPress.DB
			$disp = $meta ? json_decode( (string) $meta['display_meta'], true ) : null;
			if ( ! is_array( $disp ) ) {
				continue;
			}

			$map    = array(
				'text'        => 'text',
				'name'        => 'text',
				'address'     => 'text',
				'email'       => 'email',
				'phone'       => 'tel',
				'textarea'    => 'textarea',
				'select'      => 'select',
				'multiselect' => 'checkbox',
				'radio'       => 'radio',
				'checkbox'    => 'checkbox',
				'number'      => 'number',
				'date'        => 'date',
				'website'     => 'url',
				'fileupload'  => 'file',
				'consent'     => 'consent',
			);
			$ignore = array( 'section', 'html', 'hidden', 'captcha', 'honeypot' );
			$pages  = isset( $disp['pagination']['pages'] ) && is_array( $disp['pagination']['pages'] ) ? array_values( $disp['pagination']['pages'] ) : array();
			$page   = 1;

			$fields  = array();
			$skipped = array();
			$ids     = array();
			foreach ( (array) ( isset( $disp['fields'] ) ? $disp['fields'] : array() ) as $f ) {
				$type  = isset( $f['type'] ) ? (string) $f['type'] : '';
				$label = self::text( isset( $f['label'] ) ? $f['label'] : '' );
				if ( 'page' === $type ) {
					$title    = isset( $pages[ $page ] ) && '' !== trim( (string) $pages[ $page ] ) ? self::text( $pages[ $page ] ) : __( 'Next step', 'alpeg-forms' );
					$fields[] = self::field( 'step', $title, false, $ids );
					++$page;
					continue;
				}
				if ( ! isset( $map[ $type ] ) ) {
					if ( ! in_array( $type, $ignore, true ) ) {
						$skipped[] = $type . ( $label ? ' (' . $label . ')' : '' );
					}
					continue;
				}
				$new   = $map[ $type ];
				$extra = array(
					'placeholder' => self::text( isset( $f['placeholder'] ) ? $f['placeholder'] : '' ),
					'help'        => self::no_tags( isset( $f['description'] ) ? $f['description'] : '' ),
				);
				if ( Fields::has_options( $new ) ) {
					$extra['options'] = self::option_labels( isset( $f['choices'] ) ? $f['choices'] : array(), array( 'text', 'value' ) );
					if ( ! $extra['options'] ) {
						$skipped[] = $type . ( $label ? ' (' . $label . ')' : '' );
						continue;
					}
				}
				if ( 'consent' === $new ) {
					$text     = isset( $f['checkboxLabel'] ) && '' !== trim( (string) $f['checkboxLabel'] ) ? $f['checkboxLabel'] : $label;
					$fields[] = self::field( 'consent', self::consent_label( $text ), true, $ids );
					continue;
				}
				if ( 'file' === $new ) {
					$exts                = self::text( isset( $f['allowedExtensions'] ) ? $f['allowedExtensions'] : '' );
					$extra['accept']     = '' !== $exts ? 'custom' : 'both';
					$extra['extensions'] = str_replace( array( '.', ',' ), array( '', ', ' ), $exts );
					$extra['max_size']   = isset( $f['maxFileSize'] ) && (int) $f['maxFileSize'] > 0 ? (int) $f['maxFileSize'] : 5;
					$extra['max_files']  = ! empty( $f['multipleFiles'] ) ? max( 1, min( Files::MAX_FILES, (int) ( ! empty( $f['maxFiles'] ) ? $f['maxFiles'] : Files::MAX_FILES ) ) ) : 1;
				}
				$fields[] = self::field( $new, $label, ! empty( $f['isRequired'] ), $ids, $extra );
			}

			$notify  = '';
			$subject = '';
			$notes   = $meta ? json_decode( (string) $meta['notifications'], true ) : null;
			if ( is_array( $notes ) && $notes ) {
				$n       = reset( $notes );
				$notify  = self::plain_address( isset( $n['to'] ) ? $n['to'] : '' );
				$subject = self::no_tags( isset( $n['subject'] ) ? $n['subject'] : '' );
			}
			$success = '';
			$confs   = $meta ? json_decode( (string) $meta['confirmations'], true ) : null;
			if ( is_array( $confs ) ) {
				foreach ( $confs as $c ) {
					if ( isset( $c['type'] ) && 'message' === $c['type'] && ! empty( $c['message'] ) ) {
						$success = self::no_tags( $c['message'] );
						if ( ! empty( $c['isDefault'] ) ) {
							break;
						}
					}
				}
			}

			$out[] = Importer::result(
				'gravity',
				'Gravity Forms',
				$id,
				self::text( isset( $disp['title'] ) ? $disp['title'] : $form['title'] ),
				$fields,
				$skipped,
				array(
					'submitLabel'    => self::text( isset( $disp['button']['text'] ) ? $disp['button']['text'] : '' ),
					'notifyEmail'    => $notify,
					'notifySubject'  => $subject,
					'successMessage' => $success,
					'firstStepTitle' => isset( $pages[0] ) ? self::text( $pages[0] ) : '',
				)
			);
		}
		return $out;
	}

	/* ------------------------------------------------------------------
	 * Formidable Forms
	 * ---------------------------------------------------------------- */

	/**
	 * Forms from Formidable Forms (tables frm_forms, frm_fields; email actions as posts).
	 *
	 * @return array[]
	 */
	public static function formidable() {
		global $wpdb;
		$forms_t = $wpdb->prefix . 'frm_forms';
		$field_t = $wpdb->prefix . 'frm_fields';
		if ( ! self::table_exists( $forms_t ) || ! self::table_exists( $field_t ) ) {
			return array();
		}
		$out   = array();
		$forms = $wpdb->get_results( $wpdb->prepare( "SELECT id, name, options FROM %i WHERE is_template = 0 AND status <> 'trash' AND ( parent_form_id IS NULL OR parent_form_id = 0 ) ORDER BY id ASC", $forms_t ), ARRAY_A ); // phpcs:ignore WordPress.DB
		foreach ( (array) $forms as $form ) {
			$id   = (int) $form['id'];
			$opts = self::decode( $form['options'] );
			$rows = $wpdb->get_results( $wpdb->prepare( 'SELECT name, description, type, options, required, field_options FROM %i WHERE form_id = %d ORDER BY field_order ASC, id ASC', $field_t, $id ), ARRAY_A ); // phpcs:ignore WordPress.DB

			$map    = array(
				'text'     => 'text',
				'name'     => 'text',
				'address'  => 'text',
				'email'    => 'email',
				'phone'    => 'tel',
				'textarea' => 'textarea',
				'rte'      => 'textarea',
				'select'   => 'select',
				'radio'    => 'radio',
				'checkbox' => 'checkbox',
				'number'   => 'number',
				'date'     => 'date',
				'url'      => 'url',
				'file'     => 'file',
			);
			$ignore = array( 'html', 'hidden', 'captcha', 'divider', 'end_divider', 'user_id', 'submit', 'summary' );

			$fields  = array();
			$skipped = array();
			$ids     = array();
			foreach ( (array) $rows as $f ) {
				$type  = (string) $f['type'];
				$label = self::text( $f['name'] );
				$fopts = self::decode( $f['field_options'] );
				if ( 'break' === $type ) {
					$fields[] = self::field( 'step', '' !== $label && 'Page Break' !== $label ? $label : __( 'Next step', 'alpeg-forms' ), false, $ids );
					continue;
				}
				if ( 'gdpr' === $type ) {
					$text     = isset( $fopts['gdpr_text'] ) && '' !== $fopts['gdpr_text'] ? $fopts['gdpr_text'] : $label;
					$fields[] = self::field( 'consent', self::consent_label( $text ), true, $ids );
					continue;
				}
				if ( ! isset( $map[ $type ] ) ) {
					if ( ! in_array( $type, $ignore, true ) ) {
						$skipped[] = $type . ( $label ? ' (' . $label . ')' : '' );
					}
					continue;
				}
				$new   = $map[ $type ];
				$extra = array(
					'placeholder' => self::text( isset( $fopts['placeholder'] ) ? $fopts['placeholder'] : '' ),
					'help'        => self::no_tags( $f['description'] ),
				);
				if ( Fields::has_options( $new ) ) {
					$extra['options'] = self::option_labels( self::decode( $f['options'] ), array( 'label', 'value' ) );
					if ( ! $extra['options'] ) {
						$skipped[] = $type . ( $label ? ' (' . $label . ')' : '' );
						continue;
					}
				}
				if ( 'file' === $new ) {
					$extra['accept']    = 'both';
					$extra['max_size']  = isset( $fopts['size'] ) && (int) $fopts['size'] > 0 ? (int) $fopts['size'] : 5;
					$extra['max_files'] = ! empty( $fopts['multiple'] ) ? max( 1, min( Files::MAX_FILES, (int) ( ! empty( $fopts['max'] ) ? $fopts['max'] : Files::MAX_FILES ) ) ) : 1;
				}
				$fields[] = self::field( $new, $label, ! empty( $f['required'] ), $ids, $extra );
			}

			// Email action: post type frm_form_actions, post_excerpt "email", menu_order = form ID, JSON content.
			$notify  = '';
			$subject = '';
			$action  = $wpdb->get_var( $wpdb->prepare( "SELECT post_content FROM {$wpdb->posts} WHERE post_type = 'frm_form_actions' AND post_excerpt = 'email' AND menu_order = %d AND post_status = 'publish' ORDER BY ID ASC LIMIT 1", $id ) ); // phpcs:ignore WordPress.DB
			if ( $action ) {
				$a       = json_decode( (string) $action, true );
				$notify  = self::plain_address( isset( $a['email_to'] ) ? $a['email_to'] : '' );
				$subject = self::no_tags( isset( $a['email_subject'] ) ? $a['email_subject'] : '' );
			}

			$out[] = Importer::result(
				'formidable',
				'Formidable Forms',
				$id,
				self::text( $form['name'] ),
				$fields,
				$skipped,
				array(
					'submitLabel'    => self::text( isset( $opts['submit_value'] ) ? $opts['submit_value'] : '' ),
					'notifyEmail'    => $notify,
					'notifySubject'  => $subject,
					'successMessage' => self::no_tags( isset( $opts['success_msg'] ) ? $opts['success_msg'] : '' ),
				)
			);
		}
		return $out;
	}

	/* ------------------------------------------------------------------
	 * Fluent Forms
	 * ---------------------------------------------------------------- */

	/**
	 * Forms from Fluent Forms (tables fluentform_forms and fluentform_form_meta).
	 *
	 * @return array[]
	 */
	public static function fluent() {
		global $wpdb;
		$forms_t = $wpdb->prefix . 'fluentform_forms';
		$meta_t  = $wpdb->prefix . 'fluentform_form_meta';
		if ( ! self::table_exists( $forms_t ) ) {
			return array();
		}
		$out   = array();
		$forms = $wpdb->get_results( $wpdb->prepare( 'SELECT id, title, form_fields FROM %i ORDER BY id ASC', $forms_t ), ARRAY_A ); // phpcs:ignore WordPress.DB
		foreach ( (array) $forms as $form ) {
			$id   = (int) $form['id'];
			$data = json_decode( (string) $form['form_fields'], true );
			if ( ! is_array( $data ) ) {
				continue;
			}
			$state = array(
				'fields'  => array(),
				'skipped' => array(),
				'ids'     => array(),
				'titles'  => isset( $data['stepsWrapper']['stepStart']['settings']['step_titles'] ) ? array_values( (array) $data['stepsWrapper']['stepStart']['settings']['step_titles'] ) : array(),
				'step'    => 1,
			);
			self::fluent_walk( isset( $data['fields'] ) ? (array) $data['fields'] : array(), $state );

			$notify  = '';
			$subject = '';
			$success = '';
			if ( self::table_exists( $meta_t ) ) {
				$metas = $wpdb->get_results( $wpdb->prepare( "SELECT meta_key, value FROM %i WHERE form_id = %d AND meta_key IN ('notifications','formSettings') ORDER BY id ASC", $meta_t, $id ), ARRAY_A ); // phpcs:ignore WordPress.DB
				foreach ( (array) $metas as $m ) {
					$v = json_decode( (string) $m['value'], true );
					if ( ! is_array( $v ) ) {
						continue;
					}
					if ( 'notifications' === $m['meta_key'] && '' === $notify && ( ! isset( $v['enabled'] ) || $v['enabled'] ) ) {
						$notify  = self::plain_address( isset( $v['sendTo']['email'] ) ? $v['sendTo']['email'] : '' );
						$subject = self::no_tags( isset( $v['subject'] ) ? $v['subject'] : '' );
					} elseif ( 'formSettings' === $m['meta_key'] && isset( $v['confirmation']['messageToShow'] ) ) {
						$success = self::no_tags( $v['confirmation']['messageToShow'] );
					}
				}
			}

			$first = isset( $state['titles'][0] ) ? self::text( $state['titles'][0] ) : '';
			$out[] = Importer::result(
				'fluent',
				'Fluent Forms',
				$id,
				self::text( $form['title'] ),
				$state['fields'],
				$state['skipped'],
				array(
					'submitLabel'    => self::text( isset( $data['submitButton']['settings']['button_ui']['text'] ) ? $data['submitButton']['settings']['button_ui']['text'] : '' ),
					'notifyEmail'    => $notify,
					'notifySubject'  => $subject,
					'successMessage' => $success,
					'firstStepTitle' => $first,
				)
			);
		}
		return $out;
	}

	/**
	 * Walk the Fluent Forms field tree (containers hold columns with fields).
	 *
	 * @param array $elements Elements.
	 * @param array $state    Collected fields, skipped, IDs, step titles (by reference).
	 */
	private static function fluent_walk( array $elements, array &$state ) {
		$map    = array(
			'input_text'     => 'text',
			'input_name'     => 'text',
			'address'        => 'text',
			'input_email'    => 'email',
			'phone'          => 'tel',
			'textarea'       => 'textarea',
			'select'         => 'select',
			'select_country' => 'select',
			'input_radio'    => 'radio',
			'input_checkbox' => 'checkbox',
			'multi_select'   => 'checkbox',
			'input_number'   => 'number',
			'input_date'     => 'date',
			'input_url'      => 'url',
			'input_file'     => 'file',
			'input_image'    => 'file',
		);
		$ignore = array( 'input_hidden', 'custom_html', 'section_break', 'recaptcha', 'hcaptcha', 'turnstile', 'custom_submit_button', 'shortcode', 'action_hook' );

		foreach ( $elements as $el ) {
			if ( ! is_array( $el ) || empty( $el['element'] ) ) {
				continue;
			}
			$type     = (string) $el['element'];
			$settings = isset( $el['settings'] ) && is_array( $el['settings'] ) ? $el['settings'] : array();
			$attrs    = isset( $el['attributes'] ) && is_array( $el['attributes'] ) ? $el['attributes'] : array();

			if ( 'container' === $type ) {
				foreach ( (array) ( isset( $el['columns'] ) ? $el['columns'] : array() ) as $col ) {
					self::fluent_walk( isset( $col['fields'] ) ? (array) $col['fields'] : array(), $state );
				}
				continue;
			}
			if ( 'form_step' === $type ) {
				$title             = isset( $state['titles'][ $state['step'] ] ) ? self::text( $state['titles'][ $state['step'] ] ) : '';
				$state['fields'][] = self::field( 'step', '' !== $title ? $title : __( 'Next step', 'alpeg-forms' ), false, $state['ids'] );
				++$state['step'];
				continue;
			}

			$label = self::text( isset( $settings['label'] ) && '' !== $settings['label'] ? $settings['label'] : ( isset( $settings['admin_field_label'] ) ? $settings['admin_field_label'] : '' ) );
			$req   = ! empty( $settings['validation_rules']['required']['value'] );

			if ( 'terms_and_condition' === $type || 'gdpr_agreement' === $type ) {
				$text              = isset( $settings['tnc_html'] ) && '' !== $settings['tnc_html'] ? $settings['tnc_html'] : $label;
				$state['fields'][] = self::field( 'consent', self::consent_label( $text ), true, $state['ids'] );
				continue;
			}
			if ( ! isset( $map[ $type ] ) ) {
				if ( ! in_array( $type, $ignore, true ) ) {
					$state['skipped'][] = $type . ( $label ? ' (' . $label . ')' : '' );
				}
				continue;
			}
			$new = $map[ $type ];

			if ( 'input_name' === $type ) {
				// Name field = several inputs (first, last …): one "Name" field.
				$label = '' !== $label ? $label : __( 'Name', 'alpeg-forms' );
				foreach ( (array) ( isset( $el['fields'] ) ? $el['fields'] : array() ) as $sub ) {
					if ( ! empty( $sub['settings']['validation_rules']['required']['value'] ) ) {
						$req = true;
					}
				}
			}
			$extra = array(
				'placeholder' => self::text( isset( $attrs['placeholder'] ) ? $attrs['placeholder'] : ( isset( $settings['placeholder'] ) ? $settings['placeholder'] : '' ) ),
				'help'        => self::no_tags( isset( $settings['help_message'] ) ? $settings['help_message'] : '' ),
			);
			if ( Fields::has_options( $new ) ) {
				$opts = array();
				if ( ! empty( $settings['advanced_options'] ) && is_array( $settings['advanced_options'] ) ) {
					$opts = self::option_labels( $settings['advanced_options'], array( 'label', 'value' ) );
				} elseif ( ! empty( $el['options'] ) && is_array( $el['options'] ) ) {
					$opts = self::option_labels( array_values( $el['options'] ), array() );
				}
				if ( ! $opts ) {
					$state['skipped'][] = $type . ( $label ? ' (' . $label . ')' : '' );
					continue;
				}
				$extra['options'] = $opts;
			}
			if ( 'file' === $new ) {
				$rules             = isset( $settings['validation_rules'] ) ? $settings['validation_rules'] : array();
				$bytes             = isset( $rules['max_file_size']['value'] ) ? (int) $rules['max_file_size']['value'] : 0;
				$extra['max_size'] = $bytes > 0 ? max( 1, (int) ceil( $bytes / MB_IN_BYTES ) ) : 5;
				$extra['max_files'] = max( 1, min( Files::MAX_FILES, (int) ( isset( $rules['max_file_count']['value'] ) ? $rules['max_file_count']['value'] : 1 ) ) );
				$types             = isset( $rules['allowed_file_types']['value'] ) ? (array) $rules['allowed_file_types']['value'] : array();
				if ( 'input_image' === $type ) {
					$extra['accept'] = 'images';
				} elseif ( $types ) {
					$exts                = array_filter( array_map( 'sanitize_key', explode( '|', implode( '|', array_map( 'strval', $types ) ) ) ) );
					$extra['accept']     = 'custom';
					$extra['extensions'] = implode( ', ', $exts );
				} else {
					$extra['accept'] = 'both';
				}
			}
			$state['fields'][] = self::field( $new, $label, $req, $state['ids'], $extra );
		}
	}

	/* ------------------------------------------------------------------
	 * Helpers
	 * ---------------------------------------------------------------- */

	/**
	 * Build a field in ALPEG Forms format.
	 *
	 * @param string $type     Field type.
	 * @param string $label    Label.
	 * @param bool   $required Required.
	 * @param array  $ids      IDs used so far (by reference).
	 * @param array  $extra    Additional properties.
	 * @return array
	 */
	private static function field( $type, $label, $required, array &$ids, array $extra = array() ) {
		$label = '' !== $label ? $label : ucfirst( $type );
		$id    = Importer::unique_id( 'consent' === $type ? 'consent' : ( 'step' === $type ? 'step' : $label ), $ids );
		return array_merge(
			array(
				'id'          => $id,
				'type'        => $type,
				'label'       => $label,
				'required'    => (bool) $required,
				'placeholder' => '',
				'help'        => '',
				'width'       => 'full',
				'options'     => array(),
			),
			$extra
		);
	}

	/**
	 * Consent text: keeps links, falls back to the default text.
	 *
	 * @param string $text Text from the source plugin.
	 * @return string
	 */
	private static function consent_label( $text ) {
		$text = trim( wp_kses( (string) $text, Fields::consent_kses() ) );
		return '' !== $text ? $text : __( 'I agree that my details will be stored to process my request. More information in the <a href="{privacy}">privacy policy</a>.', 'alpeg-forms' );
	}

	/**
	 * Option labels from a list of choices.
	 *
	 * @param mixed    $choices Choices (strings or arrays).
	 * @param string[] $keys    Keys to try in order.
	 * @return string[]
	 */
	private static function option_labels( $choices, array $keys ) {
		$out = array();
		foreach ( (array) $choices as $c ) {
			$label = '';
			if ( is_array( $c ) ) {
				foreach ( $keys as $k ) {
					if ( isset( $c[ $k ] ) && '' !== trim( (string) $c[ $k ] ) ) {
						$label = (string) $c[ $k ];
						break;
					}
				}
			} elseif ( is_scalar( $c ) ) {
				$label = (string) $c;
			}
			$label = self::text( $label );
			if ( '' !== $label ) {
				$out[] = $label;
			}
		}
		return array_values( array_unique( $out ) );
	}

	/**
	 * Plain text from a value (HTML removed).
	 *
	 * @param mixed $value Value.
	 * @return string
	 */
	private static function text( $value ) {
		return is_scalar( $value ) ? trim( sanitize_text_field( wp_strip_all_tags( (string) $value ) ) ) : '';
	}

	/**
	 * Text without merge tags of the source plugin ({…} or […]); empty if only tags remain.
	 *
	 * @param mixed $value Value.
	 * @return string
	 */
	private static function no_tags( $value ) {
		$text = is_scalar( $value ) ? trim( wp_strip_all_tags( (string) $value ) ) : '';
		if ( preg_match( '/\{[^}]*\}|\[[a-z0-9_ -]+\]/i', $text ) ) {
			return '';
		}
		return sanitize_textarea_field( $text );
	}

	/**
	 * A single plain email address (merge tags like {admin_email} are dropped – our default applies).
	 *
	 * @param mixed $value Value.
	 * @return string
	 */
	private static function plain_address( $value ) {
		$value = is_scalar( $value ) ? trim( (string) $value ) : '';
		$first = trim( (string) strtok( $value, ',;' ) );
		return is_email( $first ) ? $first : '';
	}

	/**
	 * Decode stored settings: arrays stay, JSON is decoded, serialized data is read
	 * without allowing any objects (no object injection).
	 *
	 * @param mixed $value Value.
	 * @return array
	 */
	public static function decode( $value ) {
		if ( is_array( $value ) ) {
			return $value;
		}
		$value = (string) $value;
		if ( '' === $value ) {
			return array();
		}
		if ( is_serialized( $value ) ) {
			$data = @unserialize( $value, array( 'allowed_classes' => false ) ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.serialize_unserialize,WordPress.PHP.NoSilencedErrors.Discouraged -- Data written by another plugin; objects are not allowed.
			return is_array( $data ) ? $data : array();
		}
		$data = json_decode( $value, true );
		return is_array( $data ) ? $data : array();
	}

	/**
	 * Does a table exist?
	 *
	 * @param string $table Full table name.
	 * @return bool
	 */
	public static function table_exists( $table ) {
		global $wpdb;
		static $cache = array();
		if ( ! isset( $cache[ $table ] ) ) {
			$cache[ $table ] = $table === $wpdb->get_var( $wpdb->prepare( 'SHOW TABLES LIKE %s', $wpdb->esc_like( $table ) ) ); // phpcs:ignore WordPress.DB
		}
		return $cache[ $table ];
	}

}