<?php


class RoutingTableReader
{
    private $routes = [];

    /**
     * @return array
     */
    public function getRoutes(): array
    {
        return $this->routes;
    }

    public function __construct()
    {
        $result = @shell_exec("ip --json route show");

        if (!$result) {
            throw new RuntimeException("Failed to read routing table");
        }


        $this->routes = @json_decode($result, true);

        if ($this->routes === null) {
            throw new RuntimeException("Failed to parse json output");
        }

        foreach ($this->routes as $key => &$route) {
            if ($route["dst"] === "default") {
                $route["dst"] = "0.0.0.0/0";
            } elseif (!str_contains($route["dst"], "/")) {
                $route["dst"] .= "/32";
            }
        }
    }
}