#!/usr/bin/env node

var http = require("http"),
    path = require("path"),
    url = require("url"),
    fs = require("fs"),
    open = require("open"),
    optimist = require("optimist");

var defaultPort = 5555,
    usage = "Usage: $ mapshaper-gui [options]",
    opts = optimist.usage(usage)

  .options("h", {
    alias: "help",
    describe: "show this help message",
    'boolean': true
  })

  .options("p", {
    alias: "port",
    default: defaultPort,
    describe: "http port of server on localhost"
  })

  .check(function(argv) {
    if (argv.h) {
      optimist.showHelp();
      process.exit(0);
    }
  })
  .argv;

var webRoot = path.join(__dirname, "../www"),
    port = opts.port || defaultPort,
    indexUrl = "http://localhost:" + port + "/index.html";

process.on('uncaughtException', function(err) {
  if (err.errno === 'EADDRINUSE')
    console.log("Port " + port + ' is in use (Run mapshaper-gui -h for help).');
  process.exit(1);
});

serveOnPort(webRoot, port);

function serveOnPort(www, port) {
  http.createServer(function(request, response) {
    var uri = url.parse(request.url).pathname
      , filename = path.join(www, uri);

    fs.exists(filename, function(exists) {
      if(!exists) {
        response.writeHead(404, {"Content-Type": "text/plain"});
        response.write("404 Not Found\n");
        response.end();
        return;
      }

      if (fs.statSync(filename).isDirectory()) filename += '/index.html';

      fs.readFile(filename, "binary", function(err, file) {
        if(err) {
          response.writeHead(500, {"Content-Type": "text/plain"});
          response.write(err + "\n");
          response.end();
          return;
        }

        response.writeHead(200);
        response.write(file, "binary");
        response.end();
      });
    });
  }).listen(parseInt(port, 10), onListening);
}

function onListening() {
  open(indexUrl);
}