Refactor extension to webpack

This change is the biggest in the history of the project. The entire
project has been refactored so it is built with webpack.

This involves:
- Creating webpack and npm config files.
- Fixing some bugs in the code due to the fact that webpack uses strict
mode.
- Merging some pieces of code which were shared throughout the codebase
(not exhaustive, more work should be done in this direction).
- Splitting the console_inject.js file into separate files (it had 1000+
lines).
- Adapting all the build-related files (Makefile, bash scripts, etc.)
- Changing the docs to explain the new build process.
- Changing the Zuul playbook/roles to adapt to the new build process.

Change-Id: I16476d47825461c3a318b3f1a1eddb06b2df2e89
diff --git a/src/injections/profileIndicator.js b/src/injections/profileIndicator.js
new file mode 100644
index 0000000..ee897fe
--- /dev/null
+++ b/src/injections/profileIndicator.js
@@ -0,0 +1,392 @@
+import {escapeUsername} from '../common/communityConsoleUtils.js';
+
+var CCProfileRegex =
+    /^(?:https:\/\/support\.google\.com)?\/s\/community(?:\/forum\/[0-9]*)?\/user\/(?:[0-9]+)$/;
+var CCRegex = /^https:\/\/support\.google\.com\/s\/community/;
+
+const BASE_URL = 'https://support.google.com/s/community/api/';
+
+const OP_FIRST_POST = 0;
+const OP_OTHER_POSTS_READ = 1;
+const OP_OTHER_POSTS_UNREAD = 2;
+
+const OPClasses = {
+  0: 'first-post',
+  1: 'other-posts-read',
+  2: 'other-posts-unread',
+};
+
+const OPi18n = {
+  0: 'first_post',
+  1: 'other_posts_read',
+  2: 'other_posts_unread',
+};
+
+const indicatorTypes = ['numPosts', 'indicatorDot'];
+
+// Filter used as a workaround to speed up the ViewForum request.
+const FILTER_ALL_LANGUAGES =
+    'lang:(ar | bg | ca | "zh-hk" | "zh-cn" | "zh-tw" | hr | cs | da | nl | en | "en-au" | "en-gb" | et | fil | fi | fr | de | el | iw | hi | hu | id | it | ja | ko | lv | lt | ms | no | pl | "pt-br" | "pt-pt" | ro | ru | sr | sk | sl | es | "es-419" | sv | th | tr | uk | vi)';
+
+const numPostsForumArraysToSum = [3, 4];
+
+var authuser = null;
+
+function isElementInside(element, outerTag) {
+  while (element !== null && ('tagName' in element)) {
+    if (element.tagName == outerTag) return true;
+    element = element.parentNode;
+  }
+
+  return false;
+}
+
+function APIRequest(action, body) {
+  var authuserPart =
+      (authuser == '0' ? '' : '?authuser=' + encodeURIComponent(authuser));
+
+  return fetch(BASE_URL + action + authuserPart, {
+           'credentials': 'include',
+           'headers': {'content-type': 'text/plain; charset=utf-8'},
+           'body': JSON.stringify(body),
+           'method': 'POST',
+           'mode': 'cors',
+         })
+      .then(res => res.json());
+}
+
+function getPosts(query, forumId) {
+  return APIRequest('ViewForum', {
+    '1': forumId,
+    '2': {
+      '1': {
+        '2': 5,
+      },
+      '2': {
+        '1': 1,
+        '2': true,
+      },
+      '12': query,
+    },
+  });
+}
+
+function getProfile(userId, forumId) {
+  return APIRequest('ViewUser', {
+    '1': userId,
+    '2': 0,
+    '3': forumId,
+    '4': {
+      '20': true,
+    },
+  });
+}
+
+// Source:
+// https://stackoverflow.com/questions/33063774/communication-from-an-injected-script-to-the-content-script-with-a-response
+var contentScriptRequest = (function() {
+  var requestId = 0;
+  var prefix = 'TWPT-profileindicator';
+
+  function sendRequest(data) {
+    var id = requestId++;
+
+    return new Promise(function(resolve, reject) {
+      var listener = function(evt) {
+        if (evt.source === window && evt.data && evt.data.prefix === prefix &&
+            evt.data.requestId == id) {
+          // Deregister self
+          window.removeEventListener('message', listener);
+          resolve(evt.data.data);
+        }
+      };
+
+      window.addEventListener('message', listener);
+
+      var payload = {data, id, prefix};
+
+      window.dispatchEvent(
+          new CustomEvent('TWPT_sendRequest', {detail: payload}));
+    });
+  }
+
+  return {sendRequest: sendRequest};
+})();
+
+// Create profile indicator dot with a loading state, or return the numPosts
+// badge if it is already created.
+function createIndicatorDot(sourceNode, searchURL, options) {
+  if (options.numPosts) return document.querySelector('.num-posts-indicator');
+  var dotContainer = document.createElement('div');
+  dotContainer.classList.add('profile-indicator', 'profile-indicator--loading');
+  contentScriptRequest
+      .sendRequest({
+        'action': 'geti18nMessage',
+        'msg': 'inject_profileindicator_loading'
+      })
+      .then(string => dotContainer.setAttribute('title', string));
+
+  var dotLink = document.createElement('a');
+  dotLink.href = searchURL;
+  dotLink.innerText = '●';
+
+  dotContainer.appendChild(dotLink);
+  sourceNode.parentNode.appendChild(dotContainer);
+
+  return dotContainer;
+}
+
+// Create badge indicating the number of posts with a loading state
+function createNumPostsBadge(sourceNode, searchURL) {
+  var link = document.createElement('a');
+  link.href = searchURL;
+
+  var numPostsContainer = document.createElement('div');
+  numPostsContainer.classList.add(
+      'num-posts-indicator', 'num-posts-indicator--loading');
+  contentScriptRequest
+      .sendRequest({
+        'action': 'geti18nMessage',
+        'msg': 'inject_profileindicator_loading'
+      })
+      .then(string => numPostsContainer.setAttribute('title', string));
+
+  var numPostsSpan = document.createElement('span');
+  numPostsSpan.classList.add('num-posts-indicator--num');
+
+  numPostsContainer.appendChild(numPostsSpan);
+  link.appendChild(numPostsContainer);
+  sourceNode.parentNode.appendChild(link);
+  return numPostsContainer;
+}
+
+// Set the badge text
+function setNumPostsBadge(badge, text) {
+  badge.classList.remove('num-posts-indicator--loading');
+  badge.querySelector('span').classList.remove(
+      'num-posts-indicator--num--loading');
+  badge.querySelector('span').textContent = text;
+}
+
+// Get options and then handle all the indicators
+function getOptionsAndHandleIndicators(sourceNode, isCC) {
+  contentScriptRequest.sendRequest({'action': 'getProfileIndicatorOptions'})
+      .then(options => handleIndicators(sourceNode, isCC, options));
+}
+
+// Handle the profile indicator dot
+function handleIndicators(sourceNode, isCC, options) {
+  var escapedUsername = escapeUsername(
+      (isCC ? sourceNode.querySelector('.name-text').innerHTML :
+              sourceNode.querySelector('span').innerHTML));
+
+  if (isCC) {
+    var threadLink = document.location.href;
+  } else {
+    var CCLink = document.getElementById('onebar-community-console');
+    if (CCLink === null) {
+      console.error(
+          '[opindicator] The user is not a PE so the dot indicator cannot be shown in TW.');
+      return;
+    }
+    var threadLink = CCLink.href;
+  }
+
+  var forumUrlSplit = threadLink.split('/forum/');
+  if (forumUrlSplit.length < 2) {
+    console.error('[opindicator] Can\'t get forum id.');
+    return;
+  }
+
+  var forumId = forumUrlSplit[1].split('/')[0];
+
+  /*
+   * TODO(avm99963): If the TW filters ever work again, set isCCLink to isCC.
+   * Otherwise, issue #29 should be resolved:
+   * https://github.com/avm99963/infinitegforums/issues/29
+   */
+  var isCCLink = true;
+
+  var query = '(replier:"' + escapedUsername + '" | creator:"' +
+      escapedUsername + '") ' + FILTER_ALL_LANGUAGES;
+  var encodedQuery =
+      encodeURIComponent(query + (isCCLink ? ' forum:' + forumId : ''));
+  var authuserPart =
+      (authuser == '0' ?
+           '' :
+           (isCCLink ? '?' : '&') + 'authuser=' + encodeURIComponent(authuser));
+  var searchURL =
+      (isCCLink ? 'https://support.google.com/s/community/search/' +
+               encodeURIComponent('query=' + encodedQuery) + authuserPart :
+                  document.location.pathname.split('/thread')[0] +
+               '/threads?thread_filter=' + encodedQuery + authuserPart);
+
+  if (options.numPosts) {
+    var profileURL = new URL(sourceNode.href);
+    var userId =
+        profileURL.pathname.split(isCC ? 'user/' : 'profile/')[1].split('/')[0];
+
+    var numPostsContainer = createNumPostsBadge(sourceNode, searchURL);
+
+    getProfile(userId, forumId)
+        .then(res => {
+          if (!('1' in res) || !('2' in res[1])) {
+            throw new Error('Unexpected profile response.');
+            return;
+          }
+
+          contentScriptRequest.sendRequest({'action': 'getNumPostMonths'})
+              .then(months => {
+                if (!options.indicatorDot)
+                  contentScriptRequest
+                      .sendRequest({
+                        'action': 'geti18nMessage',
+                        'msg': 'inject_profileindicatoralt_numposts',
+                        'placeholders': [months]
+                      })
+                      .then(
+                          string =>
+                              numPostsContainer.setAttribute('title', string));
+
+                var numPosts = 0;
+
+                for (const index of numPostsForumArraysToSum) {
+                  if (!(index in res[1][2])) {
+                    throw new Error('Unexpected profile response.');
+                    return;
+                  }
+
+                  var i = 0;
+                  for (const month of res[1][2][index].reverse()) {
+                    if (i == months) break;
+                    numPosts += month[3] || 0;
+                    ++i;
+                  }
+                }
+
+                setNumPostsBadge(numPostsContainer, numPosts);
+              })
+              .catch(
+                  err => console.error('[opindicator] Unexpected error.', err));
+        })
+        .catch(err => {
+          console.error(
+              '[opindicator] Unexpected error. Couldn\'t load profile.', err);
+          setNumPostsBadge(numPostsContainer, '?');
+        });
+  }
+
+  if (options.indicatorDot) {
+    var dotContainer = createIndicatorDot(sourceNode, searchURL, options);
+
+    // Query threads in order to see what state the indicator should be in
+    getPosts(query, forumId)
+        .then(res => {
+          // Throw an error when the replies array is not present in the reply.
+          if (!('1' in res) || !('2' in res['1'])) {
+            // Throw a different error when the numThreads field exists and is
+            // equal to 0. This reply can be received, but is enexpected,
+            // because we know that the user has replied in at least 1 thread
+            // (the current one).
+            if (('1' in res) && ('4' in res['1']) && res['1']['4'] == 0)
+              throw new Error(
+                  'Thread list is empty ' +
+                  '(but the OP has participated in this thread, ' +
+                  'so it shouldn\'t be empty).');
+
+            throw new Error('Unexpected thread list response.');
+            return;
+          }
+
+          // Current thread ID
+          var threadUrlSplit = threadLink.split('/thread/');
+          if (threadUrlSplit.length < 2)
+            throw new Error('Can\'t get thread id.');
+
+          var currId = threadUrlSplit[1].split('/')[0];
+
+          var OPStatus = OP_FIRST_POST;
+
+          for (const thread of res['1']['2']) {
+            var id = thread['2']['1']['1'] || undefined;
+            if (id === undefined || id == currId) continue;
+
+            var isRead = thread['6'] || false;
+            if (isRead)
+              OPStatus = Math.max(OP_OTHER_POSTS_READ, OPStatus);
+            else
+              OPStatus = Math.max(OP_OTHER_POSTS_UNREAD, OPStatus);
+          }
+
+          var dotContainerPrefix =
+              (options.numPosts ? 'num-posts-indicator' : 'profile-indicator');
+
+          if (!options.numPosts)
+            dotContainer.classList.remove(dotContainerPrefix + '--loading');
+          dotContainer.classList.add(
+              dotContainerPrefix + '--' + OPClasses[OPStatus]);
+          contentScriptRequest
+              .sendRequest({
+                'action': 'geti18nMessage',
+                'msg': 'inject_profileindicator_' + OPi18n[OPStatus]
+              })
+              .then(string => dotContainer.setAttribute('title', string));
+        })
+        .catch(
+            err => console.error(
+                '[opindicator] Unexpected error. Couldn\'t load recent posts.',
+                err));
+  }
+}
+
+if (CCRegex.test(location.href)) {
+  // We are in the Community Console
+  var startup =
+      JSON.parse(document.querySelector('html').getAttribute('data-startup'));
+
+  authuser = startup[2][1] || '0';
+
+  // When the OP's username is found, call getOptionsAndHandleIndicators
+  function mutationCallback(mutationList, observer) {
+    mutationList.forEach((mutation) => {
+      if (mutation.type == 'childList') {
+        mutation.addedNodes.forEach(function(node) {
+          if (node.tagName == 'A' && ('href' in node) &&
+              CCProfileRegex.test(node.href) &&
+              node.matches(
+                  'ec-question ec-message-header .name-section ec-user-link a')) {
+            console.info('Handling profile indicator via mutation callback.');
+            getOptionsAndHandleIndicators(node, true);
+          }
+        });
+      }
+    });
+  };
+
+  var observerOptions = {
+    childList: true,
+    subtree: true,
+  }
+
+  // Before starting the mutation Observer, check if the OP's username link is
+  // already part of the page
+  var node = document.querySelector(
+      'ec-question ec-message-header .name-section ec-user-link a');
+  if (node !== null) {
+    console.info('Handling profile indicator via first check.');
+    getOptionsAndHandleIndicators(node, true);
+  }
+
+  var mutationObserver = new MutationObserver(mutationCallback);
+  mutationObserver.observe(document.body, observerOptions);
+} else {
+  // We are in TW
+  authuser = (new URL(location.href)).searchParams.get('authuser') || '0';
+
+  var node =
+      document.querySelector('.thread-question a.user-info-display-name');
+  if (node !== null)
+    getOptionsAndHandleIndicators(node, false);
+  else
+    console.error('[opindicator] Couldn\'t find username.');
+}