#!/usr/bin/php
<?php
require_once __DIR__ . "/loader.php";
const CFGFILE = "/etc/quagga/zebra.conf";
const REM_PREFIX = "! routes from file ";
try {
    $networks = (new NetworkConfigReader())->getConfigs();
    $config = new Config();
    $config->read();

    $routeParser = new RoutingTableReader();
    $routes = $routeParser->getRoutes();
    $defGatewayInterface = "";
    $defGateway = "";

    foreach ($routes as $route) {
        if ($route["dst"] === "0.0.0.0/0") {
            $defGatewayInterface = $route["dev"];
            $defGateway = $route["gateway"];
            break;
        }
    }

    if (!$defGatewayInterface) {
        throw new RuntimeException("Failed to detect default gateway interface");
    }

    $contents = file_get_contents(CFGFILE);
    $lines = explode("\n", $contents);

    //remove existing routes
    foreach ($lines as $key => $line) {
        if (str_starts_with($line, REM_PREFIX) or str_starts_with($line, "ip route ") and str_contains($line . " ", $defGateway . " ")) {
            unset($lines[$key]);
        }
    }

    //add new routes
    foreach ($config["networks"] as $key) {
        $lines[] = REM_PREFIX . $key;
        if (isset($networks[$key])) {
            foreach ($networks[$key]["networks"] as $route) {
                $lines[] = "ip route " . $route . " " . $defGateway;
            }
        }
    }

    foreach ($lines as $key => $line) {
        if (trim($line) === "") {
            unset($lines[$key]);
        }
    }

    $backupFile = CFGFILE . ".sav";

    unlink($backupFile);
    rename(CFGFILE, $backupFile);
    file_put_contents(CFGFILE, implode("\n", $lines));

    //restart zebra
    echo shell_exec($config["zebra_restart_cmd"]);
} catch (Exception $e) {
    echo "\nError:" . $e->getMessage() . "\n";
    exit(1);
}

exit(0);