<?php
/**
 * A newsletter tick-box on the sign-up form of every event page.
 *
 * @package Emails404
 */

namespace Emails404;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * For sites that show The Events Calendar's events with an Elementor Pro
 * form on each event page (often a different copy of the form per event):
 * one setting adds a newsletter tick-box to all of them, so nobody edits
 * events one by one. Set up under 404 Emails → Other forms.
 *
 * - Showing the box: `elementor/widget/render_content` ( $content, $widget )
 *   filters each widget's HTML on the page. On a single event page
 *   (is_singular( 'tribe_events' )), a Form widget gets the box - in
 *   Elementor's own acceptance-field markup, after the form's last
 *   tick-box (or before its button). Never ticked in advance. Nothing is
 *   saved in Elementor or in the events.
 * - Sending: `elementor_pro/forms/new_record` ( $record, $handler ) after
 *   Elementor has accepted the submission. Elementor's script posts the
 *   whole form, so the box arrives as form_fields[emails404_newsletter];
 *   Elementor itself ignores fields it doesn't know. The page is
 *   Elementor's posted `queried_id`, checked to be an event. Only people
 *   who ticked are sent - name and email only, with the box's wording as
 *   their consent.
 * - A form connected on its own in Other forms keeps that connection and
 *   isn't sent twice.
 */
class Event_Page_Forms {

	const OPTION = 'emails404_event_page_forms';

	/** The box's field name in the form - form_fields[emails404_newsletter]. */
	const FIELD = 'emails404_newsletter';

	const SOURCE_SLUG = 'elementor-event';

	const EVENT_POST_TYPE = 'tribe_events';

	const LABEL_MAX = 300;

	public static function is_available() {
		return defined( 'ELEMENTOR_PRO_VERSION' ) && class_exists( 'Tribe__Events__Main' );
	}

	public static function register() {
		if ( ! self::is_available() ) {
			return;
		}
		add_filter( 'elementor/widget/render_content', array( __CLASS__, 'filter_widget_content' ), 10, 2 );
		add_action( 'elementor_pro/forms/new_record', array( __CLASS__, 'handle_record' ), 20, 2 );
	}

	/** @return array{enabled:bool, form:string, label:string} */
	public static function get() {
		$saved = get_option( self::OPTION, array() );
		$saved = is_array( $saved ) ? $saved : array();
		return array(
			'enabled' => ! empty( $saved['enabled'] ),
			'form'    => isset( $saved['form'] ) ? (string) $saved['form'] : '',
			'label'   => isset( $saved['label'] ) ? (string) $saved['label'] : '',
		);
	}

	/** On, with a 404 Emails form to join. */
	public static function is_on() {
		$settings = self::get();
		return $settings['enabled'] && '' !== $settings['form'];
	}

	/** The box's wording: the site's own, or the standard one in the site's language. */
	public static function label() {
		$label = trim( self::get()['label'] );
		return '' !== $label ? $label : __( 'Send me news and offers by email', '404-emails' );
	}

	/**
	 * @param mixed    $raw       The posted section.
	 * @param string[] $known_ids The workspace's 404 Emails forms.
	 */
	public static function save( $raw, array $known_ids ) {
		$raw   = is_array( $raw ) ? $raw : array();
		$form  = isset( $raw['form'] ) ? sanitize_text_field( (string) $raw['form'] ) : '';
		$label = isset( $raw['label'] ) ? trim( sanitize_text_field( (string) $raw['label'] ) ) : '';
		if ( function_exists( 'mb_substr' ) ) {
			$label = mb_substr( $label, 0, self::LABEL_MAX );
		}
		update_option(
			self::OPTION,
			array(
				'enabled' => ! empty( $raw['enabled'] ),
				'form'    => in_array( $form, $known_ids, true ) ? $form : '',
				'label'   => $label,
			),
			false
		);
	}

	/**
	 * @param string $content The widget's HTML.
	 * @param object $widget  Elementor's widget.
	 */
	public static function filter_widget_content( $content, $widget ) {
		if ( ! is_string( $content ) || ! is_object( $widget ) || ! method_exists( $widget, 'get_name' ) || 'form' !== $widget->get_name() ) {
			return $content;
		}
		if ( ! self::is_on() || ! function_exists( 'is_singular' ) || ! is_singular( self::EVENT_POST_TYPE ) ) {
			return $content;
		}
		$id = method_exists( $widget, 'get_id' ) ? (string) $widget->get_id() : '';
		return self::add_checkbox( $content, $id, self::label() );
	}

	/**
	 * The form's HTML with the box added: after its last tick-box, or before
	 * its button. Unchanged when it isn't an Elementor form or already has it.
	 */
	public static function add_checkbox( $html, $widget_id, $label ) {
		if ( false === strpos( $html, '<form' ) || false !== strpos( $html, 'name="form_fields[' . self::FIELD . ']"' ) ) {
			return $html;
		}
		$box = self::checkbox_html( $widget_id, $label );

		$last_box = self::last_group_start( $html, 'elementor-field-type-acceptance' );
		if ( null !== $last_box ) {
			$end = self::element_end( $html, $last_box );
			if ( null !== $end ) {
				return substr( $html, 0, $end ) . $box . substr( $html, $end );
			}
		}
		if ( preg_match( '/<div\b[^>]*\bclass="[^"]*\belementor-field-type-submit\b/', $html, $match, PREG_OFFSET_CAPTURE ) ) {
			return substr( $html, 0, $match[0][1] ) . $box . substr( $html, $match[0][1] );
		}
		$close = strrpos( $html, '</form>' );
		return false === $close ? $html : substr( $html, 0, $close ) . $box . substr( $html, $close );
	}

	/** Elementor's acceptance-field markup, so the form's own styles apply. */
	public static function checkbox_html( $widget_id, $label ) {
		$id = 'form-field-' . self::FIELD . ( '' !== $widget_id ? '-' . sanitize_key( $widget_id ) : '' );
		return sprintf(
			'<div class="elementor-field-type-acceptance elementor-field-group elementor-column elementor-field-group-%1$s elementor-col-100 emails404-event-newsletter"><div class="elementor-field-subgroup"><span class="elementor-field-option"><input type="checkbox" name="form_fields[%1$s]" id="%2$s" value="on" class="elementor-field elementor-size-sm elementor-acceptance-field"> <label for="%2$s">%3$s</label></span></div></div>',
			esc_attr( self::FIELD ),
			esc_attr( $id ),
			esc_html( $label )
		);
	}

	private static function last_group_start( $html, $class ) {
		if ( ! preg_match_all( '/<div\b[^>]*\bclass="[^"]*\b' . preg_quote( $class, '/' ) . '\b[^"]*"/', $html, $matches, PREG_OFFSET_CAPTURE ) ) {
			return null;
		}
		$last = end( $matches[0] );
		return $last[1];
	}

	/** Where the <div> starting at $start closes (just after its </div>). */
	private static function element_end( $html, $start ) {
		$depth = 0;
		if ( ! preg_match_all( '/<div\b|<\/div>/i', $html, $tags, PREG_OFFSET_CAPTURE, $start ) ) {
			return null;
		}
		foreach ( $tags[0] as $tag ) {
			$depth += '</' === substr( $tag[0], 0, 2 ) ? -1 : 1;
			if ( 0 === $depth ) {
				return $tag[1] + strlen( $tag[0] );
			}
		}
		return null;
	}

	/**
	 * @param object $record  ElementorPro\Modules\Forms\Classes\Form_Record.
	 * @param object $handler The Ajax handler (not used).
	 */
	public static function handle_record( $record, $handler = null ) {
		if ( ! self::is_on() || ! Settings::is_connected() || ! is_object( $record ) || ! method_exists( $record, 'get' ) ) {
			return;
		}
		// phpcs:disable WordPress.Security.NonceVerification.Missing -- Elementor has already checked and accepted this submission; only the page and our own box are read.
		$event_id = isset( $_POST['queried_id'] ) ? absint( wp_unslash( $_POST['queried_id'] ) ) : 0;
		$ticked   = isset( $_POST['form_fields'][ self::FIELD ] ) ? sanitize_text_field( wp_unslash( $_POST['form_fields'][ self::FIELD ] ) ) : '';
		// phpcs:enable WordPress.Security.NonceVerification.Missing
		if ( ! $event_id || self::EVENT_POST_TYPE !== get_post_type( $event_id ) ) {
			return;
		}

		$settings = $record->get( 'form_settings' );
		$form_id  = is_array( $settings ) && ! empty( $settings['id'] ) ? sanitize_key( (string) $settings['id'] ) : '';
		if ( '' !== $form_id && null !== Form_Connections::get( 'elementor', $form_id ) ) {
			return; // Connected on its own - sent through that connection.
		}

		$fields = $record->get( 'fields' );
		$dto    = self::signup(
			is_array( $fields ) ? $fields : array(),
			$ticked,
			$event_id,
			(string) get_the_title( $event_id ),
			self::get()['form'],
			self::label(),
			wp_generate_uuid4()
		);
		if ( null !== $dto ) {
			Form_Connections::send( $dto, self::SOURCE_SLUG );
		}
	}

	/**
	 * The sign-up to send, or null: not ticked, or no valid email.
	 *
	 * @param array  $fields   Elementor's submitted fields: id => {id, type, title, value}.
	 * @param string $ticked   What our box sent ("on" when ticked).
	 * @param int    $event_id The event page.
	 * @param string $title    The event's title.
	 * @param string $target   The 404 Emails form to join.
	 * @param string $label    The box's wording.
	 * @param string $entity_id Unique to this submission.
	 * @return Signup_Dto|null
	 */
	public static function signup( array $fields, $ticked, $event_id, $title, $target, $label, $entity_id ) {
		$form = array(
			'id'     => 'event-' . (int) $event_id,
			'title'  => $title,
			'fields' => array(
				array(
					'key'   => self::FIELD,
					'label' => $label,
					'kind'  => Form_Connections::KIND_CONSENT,
				),
			),
		);
		$values = array( self::FIELD => $ticked );
		foreach ( $fields as $id => $field ) {
			if ( ! is_array( $field ) ) {
				continue;
			}
			$key        = (string) $id;
			$type       = isset( $field['type'] ) ? (string) $field['type'] : 'text';
			$label_text = isset( $field['title'] ) ? (string) $field['title'] : '';
			if ( 'email' === $type ) {
				$kind = Form_Connections::KIND_EMAIL;
			} elseif ( 'text' === $type ) {
				$kind = Form_Connections::kind_from_words( $key, $label_text );
			} else {
				continue;
			}
			$form['fields'][] = array(
				'key'   => $key,
				'label' => $label_text,
				'kind'  => $kind,
			);
			$values[ $key ]   = isset( $field['value'] ) ? $field['value'] : '';
		}

		return Form_Connections::build_signup(
			self::SOURCE_SLUG,
			$form,
			$values,
			array(
				'form'    => $target,
				'consent' => self::FIELD,
			),
			$entity_id,
			''
		);
	}
}