<?php
/**
 * Health REST route.
 *
 * @package Consentfold
 */

declare(strict_types=1);

namespace Consentfold\Admin;

use WP_REST_Response;
use WP_REST_Server;

/**
 * `consentfold/v1/admin/health`: what the Health tab shows (docs/subsystems.md §5.14, §5.13).
 *
 * `GET` returns the checks, each with `id`, `label`, `status` (`pass`, `warn` or `fail`), `message`, `fix` and
 * `severity`, when the home page was last read (`checked`, 0 when never) and the number of checks per status. The home
 * page is fetched when nothing valid is kept. `POST /recheck` fetches it again and answers with the same payload.
 *
 * Only administrators pass the permission check; core verifies the REST nonce for cookie-authenticated requests and
 * treats a request without it as logged out.
 */
final class HealthRoute {

	public const NAMESPACE = 'consentfold/v1';
	public const ROUTE     = '/admin/health';

	/**
	 * Health checks.
	 *
	 * @var Health
	 */
	private Health $health;

	/**
	 * Constructor.
	 *
	 * @param Health $health Health checks.
	 */
	public function __construct( Health $health ) {
		$this->health = $health;
	}

	/**
	 * Hook the routes.
	 */
	public function register(): void {
		add_action( 'rest_api_init', array( $this, 'register_routes' ) );
	}

	/**
	 * Register the routes.
	 */
	public function register_routes(): void {
		register_rest_route(
			self::NAMESPACE,
			self::ROUTE,
			array(
				'methods'             => WP_REST_Server::READABLE,
				'callback'            => array( $this, 'get' ),
				'permission_callback' => array( $this, 'can_manage' ),
			)
		);
		register_rest_route(
			self::NAMESPACE,
			self::ROUTE . '/recheck',
			array(
				'methods'             => WP_REST_Server::CREATABLE,
				'callback'            => array( $this, 'recheck' ),
				'permission_callback' => array( $this, 'can_manage' ),
			)
		);
	}

	/**
	 * Whether the current user may manage the plugin.
	 */
	public function can_manage(): bool {
		return current_user_can( Capabilities::MANAGE );
	}

	/**
	 * The checks.
	 */
	public function get(): WP_REST_Response {
		return new WP_REST_Response( $this->payload( false ) );
	}

	/**
	 * Read the home page again, then the checks.
	 */
	public function recheck(): WP_REST_Response {
		return new WP_REST_Response( $this->payload( true ) );
	}

	/**
	 * What the tab shows.
	 *
	 * @param bool $refresh Whether to read the home page again whatever is kept.
	 * @return array{checks: list<array<string, mixed>>, checked: int, counts: array{pass: int, warn: int, fail: int}}
	 */
	private function payload( bool $refresh ): array {
		$checks = $this->health->results( true, $refresh );
		$counts = array(
			Health::PASS => 0,
			Health::WARN => 0,
			Health::FAIL => 0,
		);

		foreach ( $checks as $check ) {
			++$counts[ $check['status'] ];
		}

		return array(
			'checks'  => $checks,
			'checked' => $this->health->checked(),
			'counts'  => $counts,
		);
	}
}