<?php
/**
 * Admin AJAX endpoints.
 *
 * @package AdPix\Analytics
 */

declare( strict_types = 1 );

namespace AdPix\Analytics\Controller\Admin;

use AdPix\Analytics\Contracts\BootableInterface;
use AdPix\Analytics\Contracts\QueueInterface;
use AdPix\Analytics\Service\ConnectionTester;
use AdPix\Analytics\Service\ErrorLog;
use AdPix\Analytics\Service\PageFinder;

defined( 'ABSPATH' ) || exit;

/**
 * The buttons and the page search on the settings screen.
 *
 * Each one is a state-changing or credential-using request, so each one repeats the same two checks
 * in the same order: the nonce proves the request came from our form, and the capability proves the
 * person behind it is allowed to do this. Neither substitutes for the other — a nonce travels with a
 * logged-in subscriber just as happily as with an administrator.
 */
final class AjaxController implements BootableInterface {

	/**
	 * Nonce action shared by every endpoint here.
	 */
	public const NONCE = 'adpix_analytics_admin';

	/**
	 * @var ConnectionTester
	 */
	private $tester;

	/**
	 * @var QueueInterface
	 */
	private $queue;

	/**
	 * @var ErrorLog
	 */
	private $log;

	/**
	 * @var PageFinder
	 */
	private $pages;

	/**
	 * @param ConnectionTester $tester Credential verifier.
	 * @param QueueInterface   $queue  Delivery queue.
	 * @param ErrorLog         $log    Recent failures.
	 * @param PageFinder       $pages  Title search for the excluded-pages picker.
	 */
	public function __construct( ConnectionTester $tester, QueueInterface $queue, ErrorLog $log, PageFinder $pages ) {
		$this->tester = $tester;
		$this->queue  = $queue;
		$this->log    = $log;
		$this->pages  = $pages;
	}

	/**
	 * Register hooks.
	 *
	 * Only the logged-in variant is registered. There is no `nopriv` counterpart on purpose: none of
	 * these actions has any meaning for a visitor, and registering one would publish a way to make the
	 * site spend an outbound request per hit.
	 *
	 * @return void
	 */
	public function boot(): void {
		add_action( 'wp_ajax_adpix_analytics_test', array( $this, 'test' ) );
		add_action( 'wp_ajax_adpix_analytics_purge', array( $this, 'purge' ) );
		add_action( 'wp_ajax_adpix_analytics_clear_log', array( $this, 'clear_log' ) );
		add_action( 'wp_ajax_adpix_analytics_find_pages', array( $this, 'find_pages' ) );
	}

	/**
	 * Search content by title, for the excluded-pages picker.
	 *
	 * @return void
	 */
	public function find_pages(): void {
		$this->authorize();

		// phpcs:ignore WordPress.Security.NonceVerification.Missing -- Checked in authorize().
		$search = isset( $_POST['search'] ) ? sanitize_text_field( wp_unslash( $_POST['search'] ) ) : '';

		wp_send_json_success( array( 'pages' => $this->pages->search( $search ) ) );
	}

	/**
	 * Verify the stored credentials against the collector.
	 *
	 * @return void
	 */
	public function test(): void {
		$this->authorize();

		$result = $this->tester->test();

		$payload = array(
			'ok'      => (bool) $result['ok'],
			'message' => (string) $result['message'],
		);

		// The property name is the useful confirmation: it tells the site owner they connected the
		// property they meant to, which a bare "connected" never can. The key itself is not echoed
		// back — it went out with the request, it does not need to come home.
		if ( ! empty( $result['property']['name'] ) ) {
			$payload['property'] = (string) $result['property']['name'];
		}
		if ( ! empty( $result['hmac_required'] ) ) {
			$payload['notice'] = __( 'This property requires request signing. Enable "Sign requests" below.', 'adpix-analytics' );
		}

		if ( $payload['ok'] ) {
			wp_send_json_success( $payload );
		}

		wp_send_json_error( $payload );
	}

	/**
	 * Discard everything waiting to be delivered.
	 *
	 * @return void
	 */
	public function purge(): void {
		$this->authorize();

		$removed = $this->queue->purge();

		wp_send_json_success(
			array(
				'removed' => $removed,
				'message' => sprintf(
					/* translators: %s: number of discarded events. */
					_n( '%s pending event was discarded.', '%s pending events were discarded.', $removed, 'adpix-analytics' ),
					number_format_i18n( $removed )
				),
			)
		);
	}

	/**
	 * Empty the recent-failures list.
	 *
	 * @return void
	 */
	public function clear_log(): void {
		$this->authorize();

		$this->log->clear();

		wp_send_json_success( array( 'message' => __( 'The log was cleared.', 'adpix-analytics' ) ) );
	}

	/**
	 * Refuse the request unless it came from our form and from someone entitled to make it.
	 *
	 * @return void
	 */
	private function authorize(): void {
		check_ajax_referer( self::NONCE, 'nonce' );

		if ( ! current_user_can( SettingsController::CAPABILITY ) ) {
			wp_send_json_error(
				array( 'message' => __( 'You do not have permission to do that.', 'adpix-analytics' ) ),
				403
			);
		}
	}
}