#!/usr/bin/env node

// This proxy is useful for debugging frontend issues on deployed instances of
// Metabase. You can use the frontend of a local insance in conjunction with them
// backend of a deployed instance.

var http = require("http");
var httpProxy = require("http-proxy");
var url = require("url");

var backendTarget = process.argv[2] || "https://staging.metabase.com/";
var frontendTarget = process.argv[3] || "http://127.0.0.1:3000/";

var backendHost = url.parse(backendTarget).host;
var frontendHost = url.parse(frontendTarget).host;

var listenPort = parseInt(process.argv[4] || "3001");

var proxy = httpProxy.createProxyServer({ secure: false });

var server = http.createServer(function(req, res) {
    if (/^\/app\//.test(req.url)) {
        console.log("FRONTEND: " + req.url);
        req.headers.host = frontendHost;
        proxy.web(req, res, { target: frontendTarget });
    } else {
        console.log("BACKEND:  " + req.url);
        req.headers.host = backendHost;
        proxy.web(req, res, { target: backendTarget });
    }
});

console.log("frontend target: " + frontendTarget);
console.log("backend target:  " + backendTarget);
console.log("listening port:  " + listenPort);

server.listen(listenPort);