<!DOCTYPE html>
<!--
Copyright (c) 2013 The Chromium Authors. All rights reserved.
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<link rel="import" href="/tracing/base/base.html">

<script>
'use strict';

tr.exportTo('tr.b', function() {
  var fs;
  if (tr.isNode)
    fs = require('fs');

  function guessBinary(url) {
    return /[.]gz$/.test(url) || /[.]zip$/.test(url);
  }
  function xhr(method, url, async, opt_data, force_binary) {
    var req = new XMLHttpRequest();
    req.overrideMimeType('text/plain; charset=x-user-defined');
    req.open(method, url, async);

    var isBinary = force_binary;

    if (isBinary === undefined) {
      guessBinary(url);
      if (isBinary && async)
        req.responseType = 'arraybuffer';
    }

    var data = opt_data !== undefined ? opt_data : null;

    if (!async) {
      req.send(data);
      if (req.status == 200) {
        return req.responseText;
      } else {
        throw new Error('XHR failed with status ' + req.status);
      }
    }

    var p = new Promise(function(resolve, reject) {
      req.onreadystatechange = function(aEvt) {
        if (req.readyState == 4) {
          window.setTimeout(function() {
            if (req.status == 200) {
              if (req.responseType === 'arraybuffer')
                return resolve(req.response);
              return resolve(req.responseText);
            } else {
              reject(new Error('XHR failed with status ' + req.status));
            }
          }, 0);
        }
      };
    });
    req.send(data);
    return p;
  }

  function getAsync(url) {
    // Browser.
    if (!tr.isHeadless)
      return xhr('GET', url, true);

    // Node or vinn prep.
    var filename;
    if (url.startsWith('file:///'))
      filename = url.substring(7);
    else
      filename = global.HTMLImportsLoader.hrefToAbsolutePath(url);
    var isBinary = guessBinary(url);

    // Node.
    if (tr.isNode) {
      var encoding = isBinary ? undefined : 'utf8';
      return new Promise(function(resolve, reject) {
        fs.readFile(filename, encoding, function(err, data) {
          if (err) {
            reject(err);
            return;
          }
          resolve(data);
        });
      });
    }

    // Vinn.
    return Promise.resolve().then(function() {
      if (isBinary)
        return readbuffer(filename);
      return read(filename);
    });
  }

  function getSync(url) {
    // Browser.
    if (!tr.isHeadless)
      return xhr('GET', url, false);

    // Node or vinn prep.
    var filename;
    if (url.startsWith('file:///'))  // posix
      filename = url.substring(7);
    else if (url.startsWith('file://') && url[8] === ':')  // win
      filename = url.substring(7);
    else
      filename = global.HTMLImportsLoader.hrefToAbsolutePath(url);
    var isBinary = guessBinary(url);

    // Node.
    if (tr.isNode) {
      var encoding = isBinary ? undefined : 'utf8';
      return fs.readFileSync(filename, encoding);
    }

    // Vinn.
    if (isBinary)
      return readbuffer(filename);
    return read(filename);
  }

  function postAsync(url, data) {
    if (tr.isHeadless)
      throw new Error('Only supported inside a browser');
    return xhr('POST', url, true, data);
  }

  function postTextAsync(url, data) {
    if (tr.isHeadless)
      throw new Error('Only supported inside a browser');
    return xhr('POST', url, true, data, false);
  }

  return {
    getAsync: getAsync,
    getSync: getSync,
    postAsync: postAsync
  };
});
</script>