#!/usr/local/bin/php
<?php

/**
 * Author: Maciel Meireles
 * Date: 19/10/2023
 * Version: 0.7 (beta)
 * Description: Monitors gateway statuses (up to 4) and generates an exit code based on the combination of gateway statuses. It also provides a summary of all gateways at the end.
 * Credits: Luciano Rodrigues (pfSense Ninja Course).
 */

require_once('config.inc');
require_once('interfaces.inc');
require_once('util.inc');

// Define constants
define("MAX_GATEWAYS", 4); // Maximum number of gateways to monitor
define("EXIT_CODE_TOO_MANY_GATEWAYS", 256); // Exit code when there are too many gateways
define("SHOW_DETAILS", true); // Whether to show details about each gateway
define("SEND_TELEGRAM", true); // Whether to send a Telegram message with the gateway statuses
define("USE_ICONS", true); // Whether to use icons in the Telegram message and details output
define("TELEGRAM_SCRIPT_PATH", "/usr/local/opnsense/scripts/OPNsense/Monit/sendTelegram.sh"); // Path to the Telegram script
define("LAST_STATUS_FILE", __DIR__ . "/gateway_multiwan_laststatus.txt"); // File to store the last status of each gateway

$ignoredGateways = ["gateway1", "gateway2"]; // Add gateway names you want to ignore
$statusMapping = ['none' => '0', 'loss' => '1', 'down' => '2'];
$iconMapping = ['0' => '🟢', '1' => '🟡', '2' => '🔴', '3' => '❓'];
$statusTranslation = ['none' => 'online', 'loss' => 'packet loss', 'down' => 'offline'];

// Get the current status of each gateway
$gatewayStatuses = return_gateways_status(true);

if (count($gatewayStatuses) > MAX_GATEWAYS) {
    echo "More than " . MAX_GATEWAYS . " gateways are not supported by this script.";
    exit(EXIT_CODE_TOO_MANY_GATEWAYS);
}

foreach ($ignoredGateways as $ignoredGateway) {
    unset($gatewayStatuses[$ignoredGateway]);
}

$statusNumeric = "";
$statusBinary = "";
foreach ($gatewayStatuses as $status) {
    $mappedStatus = $statusMapping[$status['status']] ?? '3';
    $statusNumeric .= $mappedStatus;
    $statusBinary .= str_pad(decbin($mappedStatus), 2, '0', STR_PAD_LEFT);
}

$statusExit = bindec($statusBinary);

$lockFile = fopen(LAST_STATUS_FILE, 'c+');
if ($lockFile && flock($lockFile, LOCK_EX)) {
    $lastStatusContent = file_get_contents(LAST_STATUS_FILE);
    $lastStatusExit = (strpos($lastStatusContent, "statusExit=") !== false) ? intval(substr(strstr($lastStatusContent, "statusExit="), 11)) : -1;

    if ($lastStatusExit !== $statusExit) {
        sendTelegram($gatewayStatuses);
        ftruncate($lockFile, 0);
        fseek($lockFile, 0);
        foreach ($gatewayStatuses as $gateway => $details) {
            fwrite($lockFile, "{$gateway}=" . ($statusTranslation[$details['status']] ?? 'unknown') . "\n");
        }
        fwrite($lockFile, "statusExit=" . $statusExit . "\n\n");
    }

    flock($lockFile, LOCK_UN);
}

fclose($lockFile);

// Show details about each gateway
if (SHOW_DETAILS) {
    foreach ($gatewayStatuses as $gateway => $details) {
        echo (USE_ICONS ? ($iconMapping[$statusMapping[$details['status']] ?? '3'] ?? '') : "") . " {$gateway}: " . ($statusTranslation[$details['status']] ?? 'unknown') . "\n";
    }
}

echo "\nExit Status: {$statusExit}\n";

// Function to send a Telegram message with the status of each gateway
function sendTelegram($gatewayStatuses) {
    global $iconMapping, $statusMapping, $statusTranslation;

    $hostname = gethostname();
    $message = "{$hostname} | Gateway Status\n";
    
    foreach ($gatewayStatuses as $gateway => $details) {
        $message .= (USE_ICONS ? ($iconMapping[$statusMapping[$details['status']] ?? '3'] ?? '') : "") . " {$gateway}: " . ($statusTranslation[$details['status']] ?? 'unknown') . "\n";
    }

    $encodedMessage = urlencode($message);
    shell_exec(TELEGRAM_SCRIPT_PATH . " \"" . escapeshellcmd($encodedMessage) . "\"");
}

exit($statusExit);

?>