// Get a Wordnik API key: http://developer.wordnik.com/
var WORDNIK_API_KEY         = "XXXX";
// Get a Twitter app key: https://apps.twitter.com/
var TWITTER_CONSUMER_KEY    = "XXXX";
var TWITTER_CONSUMER_SECRET = "XXXX";

function Start() {
  // Delete exiting triggers, if any
  var triggers = ScriptApp.getProjectTriggers();
  for (var i = 0; i < triggers.length; i++) {
    ScriptApp.deleteTrigger(triggers[i]);
  }

  // Setup trigger to post a Tweet every hour.
  ScriptApp.newTrigger("UberBut")
    .timeBased()
    .everyHours(1)
    .create();
}

// From https://github.com/googlesamples/apps-script-oauth1
function GetTwitterService() {
  // Create a new service with the given name. The name will be used when
  // persisting the authorized token, so ensure it is unique within the
  // scope of the property store.
  return OAuth1.createService('twitter')
  // Set the endpoint URLs.
  .setAccessTokenUrl('https://api.twitter.com/oauth/access_token')
  .setRequestTokenUrl('https://api.twitter.com/oauth/request_token')
  .setAuthorizationUrl('https://api.twitter.com/oauth/authorize')
  // Set the consumer key and secret.
  .setConsumerKey(TWITTER_CONSUMER_KEY)
  .setConsumerSecret(TWITTER_CONSUMER_SECRET)
  // Set the name of the callback function in the script referenced
  // above that should be invoked to complete the OAuth flow.
  .setCallbackFunction('AuthCallback')
  // Set the property store where authorized tokens should be persisted.
  .setPropertyStore(PropertiesService.getScriptProperties());
}

function TwitterFetch(url) {
  var twit = GetTwitterService();
  if (!twit.hasAccess()) {
    var authorization_url = twitterService.authorize();
    Logger.log("No Twitter access -- go to " + authorization_url + " to authorize");
    return;
  }
  return twit.fetch(url);
}
function TwitterPost(url, payload) {
  var twit = GetTwitterService();
  if (!twit.hasAccess()) {
    var authorization_url = twitterService.authorize();
    Logger.log("No Twitter access -- go to " + authorization_url + " to authorize");
    return;
  }
  return twit.fetch(url, {
    "method" : "post",
    "payload" : payload
  });
}

function AuthCallback(request) {
  var twit = GetTwitterService();
  if (twit.handleCallback(request)) {
    Logger.log('Success!');
  } else {
    Logger.log('Denied.');
  }
}

// Makes an HTTP request to the Wordnik API for a random word, given the part of speech
// Modified from: https://gist.github.com/scazon/a427f58974b6e7c80827
function RandomWord(part_of_speech){
  var content = UrlFetchApp.fetch(
    "http://api.wordnik.com/v4/words.json/randomWord?includePartOfSpeech=" +
    part_of_speech +
    "&minCorpusCount=8000&maxCorpusCount=-1&minDictionaryCount=8&" +
    "maxDictionaryCount=-1&minLength=4&maxLength=-1&api_key=" + 
    WORDNIK_API_KEY);
  var word = JSON.parse(content)["word"];
  //Logger.log("Got random word: " + word);
  return word;
}

function WordIsPartOfSpeech(word, part_of_speech){
  var content = UrlFetchApp.fetch(
    "http://api.wordnik.com/v4/word.json/" + word + "/definitions?limit=1&partOfSpeech=" + part_of_speech +
    "&api_key=" + WORDNIK_API_KEY);
  var defs = JSON.parse(content);
  return defs.length;
}

// For pluralizing: https://code.google.com/p/inflection-js/
function Pluralize(noun) {
  return noun.pluralize();
}

function StandaloneTweet() {
  var text = "";
  while (text == "") {
    var noun = RandomWord("noun");
    text = Pluralize(noun);
    if (text == noun) {
      text = "";
    }
  }
  
  // An adjective 50% of the time    
  if (Math.random() < 0.5) {
    var adjective = RandomWord("adjective");
    if (adjective != "") {
      text = adjective + " " + text;
    }
  }
  
  return "Like Uber, but for " + text + ".";
}

function ReplyTweet() {
  var props = PropertiesService.getScriptProperties();
  var max_id = props.getProperty("MAX_TWITTER_ID");
  if (max_id && max_id > 0) {
    max_id = "&since_id=" + max_id;
  } else {
    max_id = "";
  }

  var url = "https://api.twitter.com/1.1/search/tweets.json?q=" + encodeURIComponent("-from:uberbut @uberbut") + "&count=50" + max_id;
  Logger.log(url);
  response = TwitterFetch(url);
  if (response.getResponseCode() !== 200) {
    Logger.log("Got response code: " + response.getResponseCode());
    return StandaloneTweet();
  }
  data = JSON.parse(response.getContentText());
  if (!data) {
    Logger.log("Can't parse json from '" + data + "'");
    return StandaloneTweet();
  }
  
  var tweets = data.statuses;
  for (var t in tweets.reverse()) {
    tweet = tweets[t]
    props.setProperty("MAX_TWITTER_ID", tweet.id_str);
    if (!tweet.possibly_sensitive && !tweet.retweeted_status) {
      // For each word, in reverse order, try to find a noun.
      var words = tweet.text.split(" ").reverse().filter(function(w) {
        // If the word has any non-alphabetic characters or is less than 6 letters long, skip it.
        return (w.length >= 6 && w.match('^[a-zA-Z]*$'));
      });
      for (var w = 0; w < words.length; w++) {
        word = words[w];
        if (WordIsPartOfSpeech(word, "noun")) {
          var choice = Pluralize(word);
          // Check to see if the previous word is an adjective.
          if ((w < words.length - 1) && WordIsPartOfSpeech(words[w+1], "adjective")) {
            choice = words[w+1] + " " + choice;
          }
          // Done!
          var url = 'https://twitter.com/' + tweet.user.screen_name + '/status/' + tweet.id_str;
          var text = "Like Uber, but for " + choice + ".\n" + url;
          Logger.log(text);
          return text;
        }
      }
    }
  }
  
  return StandaloneTweet();
}

function UberBut() {
  try {
    var text = ReplyTweet();
    Logger.log("Tweeting: '" + text + "'");
    
    // Post to twitter:
    TwitterPost("https://api.twitter.com/1.1/statuses/update.json", {'status': text})
  } catch (f) {
    Logger.log("Error: " + f);
  }
}