A script to parse useragentstring.com HTML into test JSON

json_from_html.js

var fs = require('fs');

// Parses HTML from http://www.useragentstring.com/pages/All/

/* Build a json object like:
{
  tests: [
    {
      comment: "Internet Explorer"
    },
    {
      ua: "Mozilla/5.0 (Windows; U; MSIE 9.0; WIndows NT 9.0; en-US))",
      os: "Windows NT",
      browser: "Internet Explorer",
      version: "9"

    }
  ]
}

*/
var d = {
  tests: []
},
last_browser = 'Unknown';

function parse(data) {
    for (var i=0; i < data.length; i++) {
        switch (data[i]) {
            case '<':
              // h3 Browser Name
              if (i + 2 < data.length &&
                  data[i + 1] === 'h' &&
                  data[i + 2] === '3') {
                i = parse_h3(data, i + 3);

              // a is user agent string
              } else if (i + 1 < data.length &&
                         data[i + 1] === 'a' &&
                         (data[i + 2] === ' ' || data[i + 2] === '>')) {
                i = parse_a(data, i + 1);
              }
              break;
            default:
              // no op
              break;
        }
    }
};

function parse_h3 (data, i) {
  var new_i = data.length;
  var end = data.indexOf('</h3>', i);

  if (end === -1) {
    console.log("WARN no </h3> found. Stopping.");
  } else {
    // Sometimes there is an image tag...
    if (data[i + 1] === '<' &&
        data.indexOf('/>', i + 1) !== -1 &&
        data.indexOf('/>', i + 1) < end) {
        i = data.indexOf('/>', i + 1) + 1;

    }
    var browser = last_browser = data.substring(i + 1, end);
    d.tests.push({comment: browser});
    new_i = end;
  }
  return new_i;
}

function parse_a (data, i) {
  var new_i = data.length;
  var end = data.indexOf('</a>', i);
  if (end === -1 ) {
    console.log("WARN no </a> found. Stopping.");
  } else {

    new_i = end;
    var start = data.indexOf('>', i);
    if (start !== -1) {
      d.tests.push({
        ua: data.substring(start + 1, end),
        os: "",
        browser: last_browser,
        version: ""
      });
    }
  }
  return new_i;
}

fs.readFile('t_user_agents.html', 'utf-8', function (err, data) {
    if (err) throw err;
    parse(data);
    fs.writeFile('f_user_agents.json', JSON.stringify(d, null, 2), 'utf8');
});