<?php
/**
 * Finds a Multi-step Form element's saved settings in a document's `_elementor_data`.
 *
 * The submit route always reads config from here (the server copy), never from the request.
 *
 * @package ReactWoo\Atomic
 */

namespace ReactWoo\Atomic\Forms;

defined( 'ABSPATH' ) || exit;

final class Form_Locator {

	const ELEMENT_TYPE = 'reactwoo-multistep-form';

	/**
	 * @param int    $post_id Document id.
	 * @param string $form_id Form id prop.
	 * @return array|null Plain settings (prop values unwrapped) or null.
	 */
	public static function find( $post_id, $form_id ) {
		$post_id = (int) $post_id;
		$form_id = (string) $form_id;
		if ( $post_id <= 0 || '' === $form_id ) {
			return null;
		}
		$post = get_post( $post_id );
		if ( ! $post || 'publish' !== get_post_status( $post ) || post_password_required( $post ) ) {
			return null;
		}
		$raw  = get_post_meta( $post_id, '_elementor_data', true );
		$data = is_array( $raw ) ? $raw : json_decode( (string) $raw, true );
		if ( ! is_array( $data ) ) {
			return null;
		}
		return self::walk( $data, $form_id );
	}

	/**
	 * @param array  $elements Elements.
	 * @param string $form_id  Form id.
	 * @return array|null
	 */
	public static function walk( array $elements, $form_id ) {
		foreach ( $elements as $el ) {
			if ( ! is_array( $el ) ) {
				continue;
			}
			$type = isset( $el['widgetType'] ) ? $el['widgetType'] : ( isset( $el['elType'] ) ? $el['elType'] : '' );
			if ( self::ELEMENT_TYPE === $type && isset( $el['settings'] ) && is_array( $el['settings'] ) ) {
				$settings = self::unwrap_all( $el['settings'] );
				$id       = isset( $settings['form_id'] ) ? (string) $settings['form_id'] : '';
				if ( '' === $id && isset( $el['id'] ) ) {
					$id = 'form-' . $el['id'];
				}
				if ( $id === $form_id ) {
					$settings['form_id']    = $id;
					$settings['element_id'] = isset( $el['id'] ) ? (string) $el['id'] : '';
					return $settings;
				}
			}
			if ( ! empty( $el['elements'] ) && is_array( $el['elements'] ) ) {
				$found = self::walk( $el['elements'], $form_id );
				if ( null !== $found ) {
					return $found;
				}
			}
		}
		return null;
	}

	/**
	 * Unwrap V4 typed prop values ({"$$type": "...", "value": ...}).
	 *
	 * @param array $settings Settings.
	 * @return array
	 */
	public static function unwrap_all( array $settings ) {
		$out = array();
		foreach ( $settings as $k => $v ) {
			$out[ $k ] = self::unwrap( $v );
		}
		return $out;
	}

	/** @param mixed $v */
	public static function unwrap( $v ) {
		if ( is_array( $v ) && array_key_exists( '$$type', $v ) && array_key_exists( 'value', $v ) ) {
			return self::unwrap( $v['value'] );
		}
		return $v;
	}
}