/**
 *
 * Low Quality Score Alert
 *
 * This script finds the low QS keywords (determined by a user defined threshold)
 * and sends an email listing them. Optionally it also labels and/or pauses the
 * keywords.
 *
 * Version: 1.0
 * Google AdWords Script maintained on brainlabsdigital.com
 *
 **/


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~//
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~//
//Options

var EMAIL_ADDRESSES = ["alice@example.com", "bob@example.co.uk"];
// The address or addresses that will be emailed a list of low QS keywords
// eg ["alice@example.com", "bob@example.co.uk"] or ["eve@example.org"]

var QS_THRESHOLD = 3;
// Keywords with quality score less than or equal to this number are
// considered 'low QS'

var LABEL_KEYWORDS = true;
// If this is true, low QS keywords will be automatically labelled

var LOW_QS_LABEL_NAME = "Low QS Keyword";
// The name of the label applied to low QS keywords

var PAUSE_KEYWORDS = false;
// If this is true, low QS keywords will be automatically paused
// Set to false if you want them to stay active.



//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~//
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~//
// Functions

function main() {
  Logger.log("Pause Keywords: " + PAUSE_KEYWORDS);
  Logger.log("Label Keywords: " + LABEL_KEYWORDS);

  var keywords = findKeywordsWithQSBelow(QS_THRESHOLD);
  Logger.log("Found " + keywords.length + " keywords with low quality score");

  if (!labelExists(LOW_QS_LABEL_NAME)) {
    Logger.log(Utilities.formatString('Creating label: "%s"', LOW_QS_LABEL_NAME));
    AdWordsApp.createLabel(LOW_QS_LABEL_NAME, 'Automatically created by QS Alert', 'red');
  }

  var mutations = [
    {
      enabled: PAUSE_KEYWORDS, 
      callback: function (keyword) {
        keyword.pause();
      }
    },
    {
      enabled: LABEL_KEYWORDS,
      callback: function (keyword, currentLabels) {
        if (currentLabels.indexOf(LOW_QS_LABEL_NAME) === -1) {
          keyword.applyLabel(LOW_QS_LABEL_NAME);
        }
      }
    }
  ];

  var chunkSize = 10000; 
  var chunkedKeywords = chunkList(keywords, chunkSize);

  Logger.log("Making changes to keywords..");
  chunkedKeywords.forEach(function (keywordChunk) {
    mutateKeywords(keywordChunk, mutations);
  });

  if (keywords.length > 0) {
    sendEmail(keywords);
    Logger.log("Email sent.");
  } else {
    Logger.log("No email to send.");
  }
}

function findKeywordsWithQSBelow(threshold) {
  var query = 'SELECT Id, AdGroupId, CampaignName, AdGroupName, Criteria, QualityScore, Labels'
    + ' FROM KEYWORDS_PERFORMANCE_REPORT WHERE Status = "ENABLED" AND CampaignStatus = "ENABLED" AND AdGroupStatus = "ENABLED"'
    + ' AND HasQualityScore = "TRUE" AND QualityScore <= ' + threshold;
  var report = AdWordsApp.report(query);      
  var rows = report.rows();    

  var lowQSKeywords = [];
  while (rows.hasNext()) {
    var row = rows.next();
    var lowQSKeyword = {
      campaignName: row['CampaignName'],
      adGroupName: row['AdGroupName'],
      keywordText: row['Criteria'],
      labels: (row['Labels'].trim() === '--') ? [] : JSON.parse(row['Labels']),
      uniqueId: [row['AdGroupId'], row['Id']],
      qualityScore: row['QualityScore']
    };
    lowQSKeywords.push(lowQSKeyword);
  } 
  return lowQSKeywords;
}

function labelExists(labelName) {
  var condition = Utilities.formatString('LabelName = "%s"', labelName);
  return AdWordsApp.labels().withCondition(condition).get().hasNext();
}

function chunkList(list, chunkSize) {
  var chunks = [];
  for (var i = 0; i < list.length; i += chunkSize) {
    chunks.push(list.slice(i, i + chunkSize));
  }
  return chunks;
}

function mutateKeywords(keywords, mutations) {
  var keywordIds = keywords.map(function (keyword) {
    return keyword['uniqueId'];
  });

  var mutationsToApply = getMutationsToApply(mutations);
  var adwordsKeywords = AdWordsApp.keywords().withIds(keywordIds).get(); 

  var i = 0;
  while (adwordsKeywords.hasNext()) {
    var currentKeywordLabels = keywords[i]['labels'];
    var adwordsKeyword = adwordsKeywords.next();

    mutationsToApply.forEach(function(mutate) {
      mutate(adwordsKeyword, currentKeywordLabels);
    });
    i++;
  }
}

function getMutationsToApply(mutations) {
  var enabledMutations = mutations.filter(function (mutation) {
    return mutation['enabled'];
  });  

  return enabledMutations.map(function (condition) {
      return condition['callback'];
  });
}

function sendEmail(keywords) {
  var subject = "Low Quality Keywords Paused";
  var htmlBody =
      "<p>Keywords with a quality score of less than " + QS_THRESHOLD + "found.<p>"
      + "<p>Actions Taken:<p>"
      + "<ul>"
      + "<li><b>Paused</b>: " + PAUSE_KEYWORDS + "</li>"
      + "<li><b>Labelled</b> with <code>" + LOW_QS_LABEL_NAME + "</code>: " + LABEL_KEYWORDS + "</li>"
      + "</ul>" 
      + renderTable(keywords);

  MailApp.sendEmail({
    to: EMAIL_ADDRESSES.join(","),
    subject: subject,
    htmlBody: htmlBody
  });
}

function renderTable(keywords) {
  var header = '<table border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides">'
  + '<thead><tr>'
  + '<th>Campaign Name</th>'
  + '<th>Ad Group Name</th>'
  + '<th>Keyword Text</th>'
  + '<th>Quality Score</th>'
  + '</tr></thead><tbody>';

  var rows = keywords.reduce(function(accumulator, keyword) {
    return accumulator
      + '<tr><td>' + [
      keyword['campaignName'],
      keyword['adGroupName'],
      keyword['keywordText'],
      keyword['qualityScore']
    ].join('</td><td>')
      + '</td></tr>';
  }, "");

  var footer = '</tbody></table>';

  var table = header + rows + footer;
  return table;
}