<?php
/**
 * Captures form submissions as leads.
 *
 * @package AdPix\Analytics
 */

declare( strict_types = 1 );

namespace AdPix\Analytics\Controller\Integration;

use AdPix\Analytics\Contracts\BootableInterface;
use AdPix\Analytics\Contracts\SettingsRepositoryInterface;
use AdPix\Analytics\Model\Event;
use AdPix\Analytics\Model\Identity;
use AdPix\Analytics\Service\EventRecorder;

defined( 'ABSPATH' ) || exit;

/**
 * Turns a submitted contact form into an identified lead.
 *
 * For a site that sells by enquiry rather than by checkout, this is the conversion — the equivalent
 * of a purchase — and the email address in the form is the only identifier that will ever exist for
 * that person. Capturing it at submission time is what lets the enquiry be attributed to the campaign
 * that produced it.
 *
 * Only the fields needed to identify the person are read. The message body, and any other field the
 * form collects, is never sent anywhere.
 */
final class FormsController implements BootableInterface {

	/**
	 * @var SettingsRepositoryInterface
	 */
	private $settings;

	/**
	 * @var EventRecorder
	 */
	private $recorder;

	/**
	 * @param SettingsRepositoryInterface $settings Configuration source.
	 * @param EventRecorder               $recorder Event sender.
	 */
	public function __construct( SettingsRepositoryInterface $settings, EventRecorder $recorder ) {
		$this->settings = $settings;
		$this->recorder = $recorder;
	}

	/**
	 * Register hooks.
	 *
	 * @return void
	 */
	public function boot(): void {
		if ( ! $this->settings->load()->flag( 'track_forms' ) ) {
			return;
		}

		add_action( 'wpcf7_mail_sent', array( $this, 'on_contact_form_7' ), 20, 1 );
		add_action( 'wpforms_process_complete', array( $this, 'on_wpforms' ), 20, 4 );
		add_action( 'gform_after_submission', array( $this, 'on_gravity_forms' ), 20, 2 );
	}

	/**
	 * Contact Form 7.
	 *
	 * Hooked to mail_sent rather than before_send_mail, so a submission the plugin itself rejected as
	 * spam never becomes a lead.
	 *
	 * @param mixed $contact_form WPCF7_ContactForm instance.
	 * @return void
	 */
	public function on_contact_form_7( $contact_form ): void {
		if ( ! class_exists( 'WPCF7_Submission' ) ) {
			return;
		}

		$submission = \WPCF7_Submission::get_instance();

		if ( ! $submission || ! method_exists( $submission, 'get_posted_data' ) ) {
			return;
		}

		$posted = $submission->get_posted_data();

		$this->capture(
			is_array( $posted ) ? $posted : array(),
			'contact-form-7',
			is_object( $contact_form ) && method_exists( $contact_form, 'id' ) ? (string) $contact_form->id() : ''
		);
	}

	/**
	 * WPForms.
	 *
	 * @param array $fields    Submitted fields, keyed by field id.
	 * @param array $entry     Raw entry.
	 * @param array $form_data Form configuration.
	 * @param int   $entry_id  Stored entry id.
	 * @return void
	 */
	public function on_wpforms( $fields, $entry, $form_data, $entry_id ): void {
		unset( $entry, $entry_id );

		if ( ! is_array( $fields ) ) {
			return;
		}

		$values = array();

		foreach ( $fields as $field ) {
			if ( ! is_array( $field ) || ! isset( $field['type'], $field['value'] ) || ! is_scalar( $field['value'] ) ) {
				continue;
			}

			// WPForms types the fields, so the email is the field marked email rather than whichever one
			// happens to look like an address.
			$values[ (string) $field['type'] ] = (string) $field['value'];
		}

		$this->capture(
			$values,
			'wpforms',
			isset( $form_data['id'] ) && is_scalar( $form_data['id'] ) ? (string) $form_data['id'] : ''
		);
	}

	/**
	 * Gravity Forms.
	 *
	 * @param array $entry Submitted entry.
	 * @param array $form  Form configuration.
	 * @return void
	 */
	public function on_gravity_forms( $entry, $form ): void {
		if ( ! is_array( $entry ) || ! is_array( $form ) || ! isset( $form['fields'] ) || ! is_array( $form['fields'] ) ) {
			return;
		}

		$values = array();

		foreach ( $form['fields'] as $field ) {
			if ( ! is_object( $field ) || ! isset( $field->type, $field->id ) ) {
				continue;
			}

			$value = isset( $entry[ (string) $field->id ] ) ? $entry[ (string) $field->id ] : '';

			if ( is_scalar( $value ) && '' !== (string) $value ) {
				$values[ (string) $field->type ] = (string) $value;
			}
		}

		$this->capture(
			$values,
			'gravity-forms',
			isset( $form['id'] ) && is_scalar( $form['id'] ) ? (string) $form['id'] : ''
		);
	}

	/**
	 * Identify the submitter and record the lead.
	 *
	 * @param array<string,mixed> $values  Submitted values, keyed by field name or type.
	 * @param string              $source  Which form plugin this came from.
	 * @param string              $form_id The form's own id.
	 * @return void
	 */
	private function capture( array $values, string $source, string $form_id ): void {
		$identity = Identity::from(
			array(
				'email' => $this->find( $values, array( 'email', 'your-email', 'e-mail', 'mail' ) ),
				'phone' => $this->find( $values, array( 'phone', 'tel', 'your-phone', 'telephone', 'mobile' ) ),
			)
		);

		if ( $identity->is_empty() ) {
			// Nothing in the form identifies a person, so there is no lead to attribute — only a page
			// view that the browser tag has already recorded.
			return;
		}

		$this->recorder->identify( $identity );

		// The id changes with every submission on purpose. The same person enquiring twice is two leads,
		// unlike an order status changing twice, which is one order.
		$event_id = Event::stable_id( 'lead', $source, $form_id, wp_generate_uuid4() );

		$this->recorder->record(
			Event::create( 'generate_lead', $event_id )
				->with_identity( $identity )
				->with_properties(
					array(
						'form_source' => $source,
						'form_id'     => $form_id,
					)
				)
				->at( time() )
		);
	}

	/**
	 * First non-empty value under any of the given keys.
	 *
	 * @param array<string,mixed> $values Submitted values.
	 * @param string[]            $keys   Candidate keys, in order of preference.
	 * @return string
	 */
	private function find( array $values, array $keys ): string {
		foreach ( $keys as $key ) {
			foreach ( $values as $name => $value ) {
				if ( ! is_scalar( $value ) || '' === (string) $value ) {
					continue;
				}

				// A prefix match, because form builders name fields things like your-email-address and
				// phone_number and the site owner should not have to rename them to be measured.
				if ( 0 === strpos( strtolower( (string) $name ), $key ) ) {
					return (string) $value;
				}
			}
		}

		return '';
	}
}