import { error, info, success } from "../util/Console.js";

const queue = [];
let running = false;

function enqueue(task) {
    queue.push(task);
    if (!running) processQueue();
}

async function processQueue() {
    if (queue.length === 0) { running = false; return; }
    running = true;
    const t = queue.shift();
    try { await t(); } catch (err) { error('Q error ' + err); }
    setImmediate(processQueue);
}

async function opnsenseRequest(method, path, body = null) {
    const auth = Buffer.from(`${process.env.OPNSENSE_KEY}:${process.env.OPNSENSE_SECRET}`).toString('base64');
    const opts = {
        method,
        headers: {
            'Authorization': `Basic ${auth}`,
            'Content-Type': 'application/json',
        },
    };
    if (body) opts.body = JSON.stringify(body);
    const res = await fetch(`${process.env.OPNSENSE_HOST}${path}`, opts);
    const text = await res.text();
    try {
        return JSON.parse(text);
    } catch {
        error(`got non-json response: ${text}`);
        return null;
    }
}

async function applyRules() {
    await opnsenseRequest('POST', '/api/firewall/d_nat/apply');
}

export function enqueueNatAdd(ip, port, proto = 'tcp/udp') {
    enqueue(async () => {
        info(`adding rule udp+tcp at ${ip}:${port}`);

        await opnsenseRequest('POST', '/api/firewall/d_nat/addRule', {
            rule: {
                interface: 'wan',
                protocol: 'tcp/udp',
                destination: {
                    network: 'wanip',
                    port: `${port}`,
                },
                target: ip,
                'local-port': `${port}`,
                descr: `pelican-${ip}-${port}`,
                disabled: '0',
            }
        });

        await applyRules();
        success(`added rule udp+tcp at ${ip}:${port}`);
    });
}

export function enqueueNatRemove(ip, port, proto = 'tcp/udp') {
    enqueue(async () => {
        info(`deleting rule udp+tcp at ${ip}:${port}`);

        const result = await opnsenseRequest('POST', '/api/firewall/d_nat/searchRule', {
            current: 1,
            rowCount: 1000,
            searchPhrase: `pelican-${ip}-${port}`,
        })

        const rows = result?.rows || [];

        for (const rule of rows) {
            if (rule.descr === `pelican-${ip}-${port}`) {
                await opnsenseRequest('POST', `/api/firewall/d_nat/delRule/${rule.uuid}`);
            }
        }

        await applyRules();
        success(`deleted rule udp+tcp at ${ip}:${port}`);
    });
}