<?php

/**
 * All the form goodness and basics.
 *
 * Contains a bunch of helper methods as well.
 *
 * @since 1.0.0
 */
class WPForms_Form_Handler {

	/**
	 * Tags taxonomy.
	 *
	 * @since 1.7.5
	 */
	const TAGS_TAXONOMY = 'wpforms_form_tag';

	/**
	 * Primary class constructor.
	 *
	 * @since 1.0.0
	 */
	public function __construct() {

		$this->hooks();
	}

	/**
	 * Hooks.
	 *
	 * @since 1.7.5
	 */
	private function hooks() {

		// Register wpforms custom post type and taxonomy.
		add_action( 'init', [ $this, 'register_taxonomy' ] );
		add_action( 'init', [ $this, 'register_cpt' ] );

		// Add wpforms to new-content admin bar menu.
		add_action( 'admin_bar_menu', [ $this, 'admin_bar' ], 99 );
		add_action( 'wpforms_create_form', [ $this, 'track_first_form' ], 10, 3 );
	}

	/**
	 * Register the custom post type to be used for forms.
	 *
	 * @since 1.0.0
	 */
	public function register_cpt() {

		// phpcs:disable WPForms.PHP.ValidateHooks.InvalidHookName

		/**
		 * Filters Custom Post Type arguments.
		 *
		 * @since 1.0.0
		 *
		 * @param array $args Arguments.
		 */
		$args = apply_filters(
			'wpforms_post_type_args',
			[
				'label'               => 'WPForms',
				'public'              => false,
				'exclude_from_search' => true,
				'show_ui'             => false,
				'show_in_admin_bar'   => false,
				'rewrite'             => false,
				'query_var'           => false,
				'can_export'          => false,
				'supports'            => [ 'title', 'author', 'revisions' ],
				'capability_type'     => 'wpforms_form', // Not using 'capability_type' anywhere. It just has to be custom for security reasons.
				'map_meta_cap'        => false, // Don't let WP to map meta caps to have a granular control over this process via 'map_meta_cap' filter.
			]
		);

		// phpcs:enable WPForms.PHP.ValidateHooks.InvalidHookName

		// Register the post type.
		register_post_type( 'wpforms', $args );
	}

	/**
	 * Register the new taxonomy for tags.
	 *
	 * @since 1.7.5
	 */
	public function register_taxonomy() {

		/**
		 * Filters Tags taxonomy arguments.
		 *
		 * @since 1.7.5
		 *
		 * @param array $args Arguments.
		 */
		$args = apply_filters(
			'wpforms_form_handler_register_taxonomy_args',
			[
				'hierarchical' => false,
				'rewrite'      => false,
				'public'       => false,
			]
		);

		register_taxonomy( self::TAGS_TAXONOMY, 'wpforms', $args );
	}

	/**
	 * Add "WPForms" item to new-content admin bar menu item.
	 *
	 * @since 1.1.7.2
	 *
	 * @param WP_Admin_Bar $wp_admin_bar WP_Admin_Bar instance, passed by reference.
	 */
	public function admin_bar( $wp_admin_bar ) {

		if ( ! is_admin_bar_showing() || ! wpforms_current_user_can( 'create_forms' ) ) {
			return;
		}

		$args = [
			'id'     => 'wpforms',
			'title'  => esc_html__( 'WPForms', 'wpforms-lite' ),
			'href'   => admin_url( 'admin.php?page=wpforms-builder' ),
			'parent' => 'new-content',
		];

		$wp_admin_bar->add_node( $args );
	}

	/**
	 * Preserve the timestamp when the very first form has been created.
	 *
	 * @since 1.6.7.1
	 *
	 * @param int   $form_id Newly created form ID.
	 * @param array $form    Array past to create a new form in wp_posts table.
	 * @param array $data    Additional form data.
	 */
	public function track_first_form( $form_id, $form, $data ) {

		// Do we have the value already?
		$time = get_option( 'wpforms_forms_first_created' );

		// Check whether we have already saved this option - skip.
		if ( ! empty( $time ) ) {
			return;
		}

		// Check whether we have any forms other than the currently created one.
		$other_form = $this->get(
			'',
			[
				'posts_per_page'         => 1,
				'nopaging'               => false,
				'fields'                 => 'ids',
				'post__not_in'           => [ $form_id ],
				'update_post_meta_cache' => false,
				'update_post_term_cache' => false,
				'cap'                    => false,
			]
		);

		// As we have other forms - we are not certain about the situation, skip.
		if ( ! empty( $other_form ) ) {
			return;
		}

		add_option( 'wpforms_forms_first_created', time(), '', 'no' );
	}

	/**
	 * Fetch forms.
	 *
	 * @since 1.0.0
	 *
	 * @param mixed $id   Form ID.
	 * @param array $args Additional arguments array.
	 *
	 * @return array|bool|null|WP_Post
	 */
	public function get( $id = '', $args = [] ) {

		if ( $id === false ) {
			return false;
		}

		// phpcs:disable WPForms.PHP.ValidateHooks.InvalidHookName

		/**
		 * Allow developers to filter the WPForms_Form_Handler::get() arguments.
		 *
		 * @since 1.0.0
		 *
		 * @param array $args Arguments array.
		 * @param mixed $id   Form ID.
		 */
		$args = (array) apply_filters( 'wpforms_get_form_args', $args, $id );

		// phpcs:enable WPForms.PHP.ValidateHooks.InvalidHookName

		// By default, we should return only published forms.
		$defaults = [
			'post_status' => 'publish',
		];

		$args = (array) wp_parse_args( $args, $defaults );

		$forms = empty( $id ) ? $this->get_multiple( $args ) : $this->get_single( $id, $args );

		return ! empty( $forms ) ? $forms : false;
	}

	/**
	 * Fetch a single form.
	 *
	 * @since 1.5.8
	 *
	 * @param string|int $id   Form ID.
	 * @param array      $args Additional arguments array.
	 *
	 * @return array|bool|null|WP_Post
	 */
	protected function get_single( $id = '', $args = [] ) {

		$args = apply_filters( 'wpforms_get_single_form_args', $args, $id );

		if ( ! isset( $args['cap'] ) && wpforms()->get( 'access' )->init_allowed() ) {
			$args['cap'] = 'view_form_single';
		}

		 if ( ! empty( $args['cap'] ) && ! wpforms_current_user_can( $args['cap'], $id ) ) {
			return false;
		 }

		// @todo add $id array support
		// If ID is provided, we get a single form
		$form = get_post( absint( $id ) );

		if ( ! empty( $args['content_only'] ) ) {
			$form = ! empty( $form ) && $form->post_type === 'wpforms' ? wpforms_decode( $form->post_content ) : false;
		}

		return $form;
	}

	/**
	 * Fetch multiple forms.
	 *
	 * @since 1.5.8
	 * @since 1.7.2 Added support for $args['search']['term'] - search form title or description by term.
	 *
	 * @param array $args Additional arguments array.
	 *
	 * @return array
	 */
	protected function get_multiple( $args = [] ) {

		/**
		 * Allow developers to filter the get_multiple() arguments.
		 *
		 * @since 1.5.8
		 *
		 * @param array $args Arguments array. Almost the same as for `get_posts()` function.
		 *                    Additional element:
		 *                    ['search']['term'] - search the form title or description by term.
		 */
		$args = (array) apply_filters( 'wpforms_get_multiple_forms_args', $args );

		// No ID provided, get multiple forms.
		$defaults = [
			'orderby'          => 'id',
			'order'            => 'ASC',
			'no_found_rows'    => true,
			'nopaging'         => true,
			'suppress_filters' => false,
		];

		$args = wp_parse_args( $args, $defaults );

		$args['post_type'] = 'wpforms';

		/**
		 * Allow developers to execute some code before get_posts() call inside \WPForms_Form_Handler::get_multiple().
		 *
		 * @since 1.7.2
		 *
		 * @param array $args Arguments of the `get_posts()`.
		 */
		do_action( 'wpforms_form_handler_get_multiple_before_get_posts', $args );

		$forms = get_posts( $args );

		/**
		 * Allow developers to execute some code right after get_posts() call inside \WPForms_Form_Handler::get_multiple().
		 *
		 * @since 1.7.2
		 *
		 * @param array $args  Arguments of the `get_posts`.
		 * @param array $forms Forms data. Result of getting multiple forms.
		 */
		do_action( 'wpforms_form_handler_get_multiple_after_get_posts', $args, $forms );

		/**
		 * Allow developers to filter the result of get_multiple().
		 *
		 * @since 1.7.2
		 *
		 * @param array $forms Result of getting multiple forms.
		 */
		return apply_filters( 'wpforms_form_handler_get_multiple_forms_result', $forms );
	}

	/**
	 * Update the form status.
	 *
	 * @since 1.7.3
	 *
	 * @param int    $form_id Form ID.
	 * @param string $status  New status.
	 *
	 * @return bool
	 */
	public function update_status( $form_id, $status ) {

		// Status updates are used only in trash and restore actions,
		// which are actually part of the deletion operation.
		// Therefore, we should check the `delete_form_single` and not `edit_form_single` permission.
		if ( ! wpforms_current_user_can( 'delete_form_single', $form_id ) ) {
			return false;
		}

		$form_id = absint( $form_id );
		$status  = empty( $status ) ? 'publish' : sanitize_key( $status );

		/**
		 * Filters the allowed form statuses.
		 *
		 * @since 1.7.3
		 *
		 * @param array $allowed_statuses Array of allowed form statuses. Default: publish, trash.
		 */
		$allowed = (array) apply_filters( 'wpforms_form_handler_update_status_allowed', [ 'publish', 'trash' ] );

		if ( ! in_array( $status, $allowed, true ) ) {
			return false;
		}

		$result = wp_update_post(
			[
				'ID'          => $form_id,
				'post_status' => $status,
			]
		);

		/**
		 * Allow developers to execute some code after changing form status.
		 *
		 * @since 1.8.1
		 *
		 * @param string $form_id Form ID.
		 * @param string $status  New form status, `publish` or `trash`.
		 */
		do_action( 'wpforms_form_handler_update_status', $form_id, $status );

		return $result !== 0;
	}

	/**
	 * Delete all forms in the Trash.
	 *
	 * @since 1.7.3
	 *
	 * @return int|bool Number of deleted forms OR false.
	 */
	public function empty_trash() {

		$forms = $this->get_multiple(
			[
				'post_status'      => 'trash',
				'fields'           => 'ids',
				'suppress_filters' => true,
			]
		);

		if ( empty( $forms ) ) {
			return false;
		}

		return $this->delete( $forms ) ? count( $forms ) : false;
	}

	/**
	 * Delete forms.
	 *
	 * @since 1.0.0
	 *
	 * @param array $ids Form IDs.
	 *
	 * @return bool
	 */
	public function delete( $ids = [] ) {

		if ( ! is_array( $ids ) ) {
			$ids = [ $ids ];
		}

		$ids = array_map( 'absint', $ids );

		foreach ( $ids as $id ) {

			// Check for permissions.
			if ( ! wpforms_current_user_can( 'delete_form_single', $id ) ) {
				return false;
			}

			if ( class_exists( 'WPForms_Entry_Handler', false ) ) {
				wpforms()->entry->delete_by( 'form_id', $id );
				wpforms()->entry_meta->delete_by( 'form_id', $id );
				wpforms()->entry_fields->delete_by( 'form_id', $id );
			}

			$form = wp_delete_post( $id, true );

			if ( ! $form ) {
				return false;
			}
		}

		do_action( 'wpforms_delete_form', $ids );

		return true;
	}

	/**
	 * Add new form.
	 *
	 * @since 1.0.0
	 *
	 * @param string $title Form title.
	 * @param array  $args  Additional arguments.
	 * @param array  $data  Form data.
	 *
	 * @return mixed
	 */
	public function add( $title = '', $args = [], $data = [] ) {

		// Must have a title.
		if ( empty( $title ) ) {
			return false;
		}

		// Check for permissions.
		if ( ! wpforms_current_user_can( 'create_forms' ) ) {
			return false;
		}

		// This filter breaks forms if they contain HTML.
		remove_filter( 'content_save_pre', 'balanceTags', 50 );

		// Add filter of the link rel attr to avoid JSON damage.
		add_filter( 'wp_targeted_link_rel', '__return_empty_string', 50, 1 );

		// phpcs:disable WPForms.PHP.ValidateHooks.InvalidHookName

		/**
		 * Filters form creation arguments.
		 *
		 * @since 1.0.0
		 *
		 * @param array $args Form creation arguments.
		 * @param array $data Additional data.
		 */
		$args = apply_filters( 'wpforms_create_form_args', $args, $data );

		// phpcs:enable WPForms.PHP.ValidateHooks.InvalidHookName

		$form_content = [
			'field_id' => '0',
			'settings' => [
				'form_title' => sanitize_text_field( $title ),
				'form_desc'  => '',
			],
		];

		$args_form_data = isset( $args['post_content'] ) ? json_decode( wp_unslash( $args['post_content'] ), true ) : null;

		// Prevent $args['post_content'] from overwriting predefined $form_content.
		// Typically, it happens if the form was created with a form template and a user was not redirected to a form editing screen afterwards.
		// This is only possible if a user has 'wpforms_create_forms' and no 'wpforms_edit_own_forms' capability.
		if ( is_array( $args_form_data ) ) {
			$args['post_content'] = wpforms_encode( array_replace_recursive( $form_content, $args_form_data ) );
		}

		// Merge args and create the form.
		$form = wp_parse_args(
			$args,
			[
				'post_title'   => esc_html( $title ),
				'post_status'  => 'publish',
				'post_type'    => 'wpforms',
				'post_content' => wpforms_encode( $form_content ),
			]
		);

		$form_id = wp_insert_post( $form );

		// Set form tags.
		if ( ! empty( $form_id ) && ! empty( $args_form_data['settings']['form_tags'] ) ) {
			wp_set_post_terms(
				$form_id,
				implode( ',', $args_form_data['settings']['form_tags'] ),
				self::TAGS_TAXONOMY
			);
		}

		// If user has no editing permissions the form considered to be created out of the WPForms form builder's context.
		if ( ! wpforms_current_user_can( 'edit_form_single', $form_id ) ) {
			$data['builder'] = false;
		}

		// If the form is created outside the context of the WPForms form
		// builder, then we define some additional default values.
		if ( ! empty( $form_id ) && isset( $data['builder'] ) && $data['builder'] === false ) {
			$form_data                                       = json_decode( wp_unslash( $form['post_content'] ), true );
			$form_data['id']                                 = $form_id;
			$form_data['settings']['submit_text']            = esc_html__( 'Submit', 'wpforms-lite' );
			$form_data['settings']['submit_text_processing'] = esc_html__( 'Sending...', 'wpforms-lite' );
			$form_data['settings']['notification_enable']    = '1';
			$form_data['settings']['notifications']          = [
				'1' => [
					'email'          => '{admin_email}',
					'subject'        => sprintf( /* translators: %s - form name. */
						esc_html__( 'New Entry: %s', 'wpforms-lite' ),
						esc_html( $title )
					),
					'sender_name'    => get_bloginfo( 'name' ),
					'sender_address' => '{admin_email}',
					'replyto'        => '{field_id="1"}',
					'message'        => '{all_fields}',
				],
			];
			$form_data['settings']['confirmations']          = [
				'1' => [
					'type'           => 'message',
					'message'        => esc_html__( 'Thanks for contacting us! We will be in touch with you shortly.', 'wpforms-lite' ),
					'message_scroll' => '1',
				],
			];

			$this->update( $form_id, $form_data, [ 'cap' => 'create_forms' ] );
		}

		// phpcs:disable WPForms.PHP.ValidateHooks.InvalidHookName

		/**
		 * Fires after the form was created.
		 *
		 * @since 1.0.0
		 *
		 * @param int   $form_id Form ID.
		 * @param array $form    Form data.
		 * @param array $data    Additional data.
		 */
		do_action( 'wpforms_create_form', $form_id, $form, $data );

		// phpcs:enable WPForms.PHP.ValidateHooks.InvalidHookName

		return $form_id;
	}

	/**
	 * Update form.
	 *
	 * @since    1.0.0
	 *
	 * @param string|int $form_id Form ID.
	 * @param array      $data    Data retrieved from $_POST and processed.
	 * @param array      $args    Empty by default, may have custom data not intended to be saved.
	 *
	 * @return mixed
	 * @internal param string $title
	 */
	public function update( $form_id = '', $data = [], $args = [] ) {

		if ( empty( $data ) ) {
			return false;
		}

		if ( empty( $form_id ) && isset( $data['id'] ) ) {
			$form_id = $data['id'];
		}

		if ( ! isset( $args['cap'] ) ) {
			$args['cap'] = 'edit_form_single';
		}

		if ( ! empty( $args['cap'] ) && ! wpforms_current_user_can( $args['cap'], $form_id ) ) {
			return false;
		}

		// This filter breaks forms if they contain HTML.
		remove_filter( 'content_save_pre', 'balanceTags', 50 );

		// Add filter of the link rel attr to avoid JSON damage.
		add_filter( 'wp_targeted_link_rel', '__return_empty_string', 50, 1 );

		$data = wp_unslash( $data );

		$title = empty( $data['settings']['form_title'] ) ? get_the_title( $form_id ) : $data['settings']['form_title'];
		$desc  = empty( $data['settings']['form_desc'] ) ? '' : $data['settings']['form_desc'];

		$data['field_id'] = ! empty( $data['field_id'] ) ? absint( $data['field_id'] ) : '0';

		// Preserve form meta.
		$meta = $this->get_meta( $form_id );

		if ( $meta ) {
			$data['meta'] = $meta;
		}

		// Preserve fields meta.
		if ( isset( $data['fields'] ) ) {
			$data['fields'] = $this->update__preserve_fields_meta( $data['fields'], $form_id );
		}

		// Sanitize - don't allow tags for users who do not have appropriate cap.
		// If we don't do this, forms for these users can get corrupt due to
		// conflicts with wp_kses().
		if ( ! current_user_can( 'unfiltered_html' ) ) {
			$data = map_deep( $data, 'wp_strip_all_tags' );
		}

		// Sanitize notifications names.
		if ( isset( $data['settings']['notifications'] ) ) {
			$data['settings']['notifications'] = $this->update__sanitize_notifications_names( $data['settings']['notifications'] );
		}
		unset( $notification );

		$form = apply_filters(
			'wpforms_save_form_args',
			[
				'ID'           => $form_id,
				'post_title'   => esc_html( $title ),
				'post_excerpt' => $desc,
				'post_content' => wpforms_encode( $data ),
			],
			$data,
			$args
		);

		$_form_id = wp_update_post( $form );

		do_action( 'wpforms_save_form', $_form_id, $form );

		return $_form_id;
	}

	/**
	 * Preserve fields meta in 'update' method.
	 *
	 * @since 1.5.8
	 *
	 * @param array      $fields  Form fields.
	 * @param string|int $form_id Form ID.
	 *
	 * @return array
	 */
	protected function update__preserve_fields_meta( $fields, $form_id ) {

		foreach ( $fields as $i => $field_data ) {
			if ( isset( $field_data['id'] ) ) {
				$field_meta = $this->get_field_meta( $form_id, $field_data['id'] );
				if ( $field_meta ) {
					$fields[ $i ]['meta'] = $field_meta;
				}
			}
		}

		return $fields;
	}

	/**
	 * Sanitize notifications names meta in 'update' method.
	 *
	 * @since 1.5.8
	 *
	 * @param array $notifications Form notifications.
	 *
	 * @return array
	 */
	protected function update__sanitize_notifications_names( $notifications ) {

		foreach ( $notifications as $id => &$notification ) {
			if ( ! empty( $notification['notification_name'] ) ) {
				$notification['notification_name'] = sanitize_text_field( $notification['notification_name'] );
			}
		}

		return $notifications;
	}

	/**
	 * Duplicate forms.
	 *
	 * @since 1.1.4
	 *
	 * @param array $ids Form IDs to duplicate.
	 *
	 * @return bool
	 */
	public function duplicate( $ids = [] ) {

		// Check for permissions.
		if ( ! wpforms_current_user_can( 'create_forms' ) ) {
			return false;
		}

		// Add filter of the link rel attr to avoid JSON damage.
		add_filter( 'wp_targeted_link_rel', '__return_empty_string', 50, 1 );

		// This filter breaks forms if they contain HTML.
		remove_filter( 'content_save_pre', 'balanceTags', 50 );

		if ( ! is_array( $ids ) ) {
			$ids = [ $ids ];
		}

		$ids = array_map( 'absint', $ids );

		foreach ( $ids as $id ) {

			// Get original entry.
			$form = get_post( $id );

			if ( ! wpforms_current_user_can( 'view_form_single', $id ) ) {
				return false;
			}

			// Confirm form exists.
			if ( ! $form || empty( $form ) ) {
				return false;
			}

			// Get the form data.
			$new_form_data = wpforms_decode( $form->post_content );

			// Remove form ID from title if present.
			$new_form_data['settings']['form_title'] = str_replace( '(ID #' . absint( $id ) . ')', '', $new_form_data['settings']['form_title'] );

			// Create the duplicate form.
			$new_form    = [
				'post_content' => wpforms_encode( $new_form_data ),
				'post_excerpt' => $form->post_excerpt,
				'post_status'  => $form->post_status,
				'post_title'   => $new_form_data['settings']['form_title'],
				'post_type'    => $form->post_type,
			];
			$new_form_id = wp_insert_post( $new_form );

			if ( ! $new_form_id || is_wp_error( $new_form_id ) ) {
				return false;
			}

			// Set new form name.
			$new_form_data['settings']['form_title'] .= ' (ID #' . absint( $new_form_id ) . ')';

			// Set new form ID.
			$new_form_data['id'] = absint( $new_form_id );

			// Update new duplicate form.
			$new_form_id = $this->update( $new_form_id, $new_form_data, [ 'cap' => 'create_forms' ] );

			if ( ! $new_form_id || is_wp_error( $new_form_id ) ) {
				return false;
			}

			// Add tags to the new form.
			if ( ! empty( $new_form_data['settings']['form_tags'] ) ) {
				wp_set_post_terms(
					$new_form_id,
					implode( ',', (array) $new_form_data['settings']['form_tags'] ),
					self::TAGS_TAXONOMY
				);
			}

			/**
			 * Fires after the form was duplicated.
			 *
			 * @since 1.8.2.2
			 *
			 * @param int   $id            Original form ID.
			 * @param int   $new_form_id   New form ID.
			 * @param array $new_form_data New form data.
			 */
			do_action( 'wpforms_form_handler_duplicate_form', $id, $new_form_id, $new_form_data );
		}

		return true;
	}

	/**
	 * Get the next available field ID and increment by one.
	 *
	 * @since 1.0.0
	 *
	 * @param string|int $form_id Form ID.
	 * @param array      $args    Additional arguments.
	 *
	 * @return mixed int or false
	 */
	public function next_field_id( $form_id, $args = [] ) { // phpcs:ignore WPForms.PHP.HooksMethod.InvalidPlaceForAddingHooks

		if ( empty( $form_id ) ) {
			return false;
		}

		$defaults = [
			'content_only' => true,
		];

		if ( isset( $args['cap'] ) ) {
			$defaults['cap'] = $args['cap'];
		}

		$form = $this->get( $form_id, $defaults );

		if ( empty( $form ) ) {
			return false;
		}

		$field_id     = 0;
		$max_field_id = ! empty( $form['fields'] ) ? max( array_keys( $form['fields'] ) ) : 0;

		// We pass the `field_id` after duplicating the Layout field that contains a bunch of fields.
		// This is needed to avoid multiple AJAX calls after duplicating each field in the Layout.
		if ( isset( $args['field_id'] ) ) {

			$set_field_id = absint( $args['field_id'] ) - 1;
			$field_id     = $set_field_id > $max_field_id ? $set_field_id : $max_field_id + 1;

		} elseif ( ! empty( $form['field_id'] ) ) {

			$field_id = absint( $form['field_id'] );
			$field_id = $max_field_id > $field_id ? $max_field_id + 1 : $field_id;
		}

		$form['field_id'] = $field_id + 1;

		// Skip creating a revision for this action.
		remove_action( 'post_updated', 'wp_save_post_revision' );

		$this->update( $form_id, $form );

		// Restore the initial revisions state.
		add_action( 'post_updated', 'wp_save_post_revision', 10, 1 );

		return $field_id;
	}

	/**
	 * Get private meta information for a form.
	 *
	 * @since 1.0.0
	 *
	 * @param string|int $form_id Form ID.
	 * @param string     $field   Field.
	 * @param array      $args    Additional arguments.
	 *
	 * @return false|array
	 */
	public function get_meta( $form_id, $field = '', $args = [] ) {

		if ( empty( $form_id ) ) {
			return false;
		}

		$defaults = [
			'content_only' => true,
		];

		if ( isset( $args['cap'] ) ) {
			$defaults['cap'] = $args['cap'];
		}

		$data = $this->get( $form_id, $defaults );

		if ( ! isset( $data['meta'] ) ) {
			return false;
		}

		if ( empty( $field ) ) {
			return $data['meta'];
		}

		if ( isset( $data['meta'][ $field ] ) ) {
			return $data['meta'][ $field ];
		}

		return false;
	}

	/**
	 * Update or add form meta information to a form.
	 *
	 * @since 1.4.0
	 *
	 * @param string|int $form_id    Form ID.
	 * @param string     $meta_key   Meta key.
	 * @param mixed      $meta_value Meta value.
	 * @param array      $args       Additional arguments.
	 *
	 * @return false|int|WP_Error
	 */
	public function update_meta( $form_id, $meta_key, $meta_value, $args = [] ) {

		if ( empty( $form_id ) || empty( $meta_key ) ) {
			return false;
		}

		// Add filter of the link rel attr to avoid JSON damage.
		add_filter( 'wp_targeted_link_rel', '__return_empty_string', 50, 1 );

		// This filter breaks forms if they contain HTML.
		remove_filter( 'content_save_pre', 'balanceTags', 50 );

		if ( ! isset( $args['cap'] ) ) {
			$args['cap'] = 'edit_form_single';
		}

		$form = $this->get_single( absint( $form_id ), $args );

		if ( empty( $form ) ) {
			return false;
		}

		$data     = wpforms_decode( $form->post_content );
		$meta_key = wpforms_sanitize_key( $meta_key );

		$data['meta'][ $meta_key ] = $meta_value;

		$form    = [
			'ID'           => $form_id,
			'post_content' => wpforms_encode( $data ),
		];
		$form    = apply_filters( 'wpforms_update_form_meta_args', $form, $data );
		$form_id = wp_update_post( $form );

		do_action( 'wpforms_update_form_meta', $form_id, $form, $meta_key, $meta_value );

		return $form_id;
	}

	/**
	 * Delete form meta information from a form.
	 *
	 * @since 1.4.0
	 *
	 * @param string|int $form_id  Form ID.
	 * @param string     $meta_key Meta key.
	 * @param array      $args     Additional arguments.
	 *
	 * @return false|int|WP_Error
	 */
	public function delete_meta( $form_id, $meta_key, $args = [] ) {

		if ( empty( $form_id ) || empty( $meta_key ) ) {
			return false;
		}

		// Add filter of the link rel attr to avoid JSON damage.
		add_filter( 'wp_targeted_link_rel', '__return_empty_string', 50, 1 );

		// This filter breaks forms if they contain HTML.
		remove_filter( 'content_save_pre', 'balanceTags', 50 );

		if ( ! isset( $args['cap'] ) ) {
			$args['cap'] = 'edit_form_single';
		}

		$form = $this->get_single( absint( $form_id ), $args );

		if ( empty( $form ) ) {
			return false;
		}

		$data     = wpforms_decode( $form->post_content );
		$meta_key = wpforms_sanitize_key( $meta_key );

		unset( $data['meta'][ $meta_key ] );

		$form    = [
			'ID'           => $form_id,
			'post_content' => wpforms_encode( $data ),
		];
		$form    = apply_filters( 'wpforms_delete_form_meta_args', $form, $data );
		$form_id = wp_update_post( $form );

		do_action( 'wpforms_delete_form_meta', $form_id, $form, $meta_key );

		return $form_id;
	}

	/**
	 * Get private meta information for a form field.
	 *
	 * @since 1.0.0
	 *
	 * @param string|int $form_id  Form ID.
	 * @param string     $field_id Field ID.
	 * @param array      $args     Additional arguments.
	 *
	 * @return array|false
	 */
	public function get_field( $form_id, $field_id = '', $args = [] ) {

		if ( empty( $form_id ) ) {
			return false;
		}

		$defaults = [
			'content_only' => true,
		];

		if ( isset( $args['cap'] ) ) {
			$defaults['cap'] = $args['cap'];
		}

		$data = $this->get( $form_id, $defaults );

		return isset( $data['fields'][ $field_id ] ) ? $data['fields'][ $field_id ] : false;
	}

	/**
	 * Get private meta information for a form field.
	 *
	 * @since 1.0.0
	 *
	 * @param string|int $form_id  Form ID.
	 * @param string     $field_id Field ID.
	 * @param array      $args     Additional arguments.
	 *
	 * @return array|false
	 */
	public function get_field_meta( $form_id, $field_id = '', $args = [] ) {

		$field = $this->get_field( $form_id, $field_id, $args );

		if ( ! $field ) {
			return false;
		}

		return isset( $field['meta'] ) ? $field['meta'] : false;
	}
}