define(['jquery', 'underscore', 'backbone', 'models/SolrResult'],
  function($, _, Backbone, SolrResult) {
  'use strict';


  var CitationView = Backbone.View.extend({

    type: "Citation",

    initialize: function(options){
      if((options === undefined) || (!options)) var options = {};

      this.id       = options.id      || null;
      this.attributes = options.attributes || null;
      this.className += options.className  || "";
      this.model     = options.model    || null;
      this.metadata   = options.metadata   || null;
      this.title      = options.title      || null;
      this.createLink = (options.createLink === false) ? false : true;
      this.createTitleLink = (options.createTitleLink === false) ? false : true;

      //If a metadata doc was passed but no data or package model, then save the metadata as our model, too
      if(!this.model && this.metadata) this.model = this.metadata;
      //If the model is a Package, then get the metadata doc in this package
      else if(this.model && this.model.type == "Package")
        this.metadata = this.model.getMetadata();
      //If the model is a metadata doc and there was no other metadata specified, then use the model
      else if(this.model && (this.model.getType && this.model.getType() == "metadata") && !this.metadata)
        this.metadata = this.model;

      //Check if the given metadata object is a portal or collection
      if( this.metadata ){
        this.isCollection = this.metadata.getType() == "collection" || this.metadata.getType() == "portal";
      }

      if( !this.metadata ){
        this.metadata = this.model;
      }

    },

    tagName : "cite",

    className : "citation",

    /*
     * Creates a citation
     */
    render: function(){

      if (!this.model && !this.metadata && !this.id)
        return this;
      else if(!this.model && !this.metadata && this.id){
        //Create a model
         this.metadata = new SolrResult({id: this.id});
         this.model = this.metadata;

         //Retrieve the citation info for this model and render once we have it
         var view = this;
         this.model.on("change", function(){ view.render.call(view); });
         this.model.getCitationInfo();
         return;
      }
      // If the model is retreived from the Metrics Service
      // and of type CitationModel, simply set the fields as
      //  retrieved from the response
      else if(this.model.type == "CitationModel") {
        var authorText = this.model.get("origin") || "",
          datasource = this.model.get("journal"),
          dateUploaded = this.model.get("year_of_publishing"),
          sourceUrl = this.model.get("source_url"),
          sourceId = this.model.get("source_id"),
          title = this.model.get("title"),
          journal =this.model.get("publisher"),
          volume =this.model.get("volume"),
          page =this.model.get("page"),
          citationMetadata =this.model.get("citationMetadata");


        // Format the Author textarea        else if (this.model.type == "CitationModel") {
        if (authorText.length > 0) {
                  var authors = authorText.split(", "),
            count = 0,
            authorText = "";

          _.each(authors, function (author) {
            count++;

            if(count == 6){
              authorText += ", et al. ";
              return;
            }
            else if(count > 6)
              return;

            if(count > 1){
              if(authors.length > 2) authorText += ",";

              if (count == authors.length) authorText += " and";

              if (authors.length > 1) authorText += " ";
            }

            // Checking for incorrectly escaped characters
            if (/&[A-Za-z0-9]/.test(author)) {

              // initializing the DOM parser
              var parser = new DOMParser();

              // parsing the incorrectly escaped `&`
              var unescapeAmpersand = parser.parseFromString(author, 'text/html');

              // unescaping the & and retrieving the actual character
              var unescapedString =  parser.parseFromString(unescapeAmpersand.body.textContent, 'text/html');

              // saving the correct author text before displaying
              author = unescapedString.body.textContent;
            }
            authorText += author;

            if (count == authors.length) authorText += ". ";
          });

        }
      }
       else if(this.metadata && this.metadata.get("archived") && !MetacatUI.appModel.get("archivedContentIsIndexed")){
         this.$el.append('<span class="danger">This content has been archived. </span>');

         //The ID
        var idEl = this.createIDElement();
         this.$el.append(idEl);

         return this;
       }
      //Create the citation from the metadata doc if we have one
      else if (this.metadata) {

        //If this object is in progress of saving, don't RErender this view.
        if(this.metadata.get("uploadStatus") == "p" && this.$el.children().length)
          return;

        //Clear the element
        this.$el.html("");

        var pubDate = this.metadata.get("pubDate"),
          dateUploaded = this.metadata.get("dateUploaded"),
          title = Array.isArray(this.metadata.get("title")) ? (this.metadata.get("title")[0] || this.title || "") : this.metadata.get("title") || this.title || "",
          datasource = this.metadata.get("datasource");

        //Format the author text
        if(this.metadata.type == "EML"){
          var authors = this.metadata.get("creator"),
            count = 0,
            authorText = "";

          _.each(authors, function (author) {
            count++;

            if(count == 6){
                     authorText += ", et al. ";
                     return;
                   }
                   else if(count > 6)
                     return;

                   //Get the individual's name, or position name, or organization name, in that order
            var name = author.get("individualName") ?
                  _.flatten([author.get("individualName").givenName, author.get("individualName").surName]).join(" ") :
                  author.get("positionName") || author.get("organizationName");

            if(count > 1){
                     if(authors.length > 2) authorText += ",";

              if (count == authors.length) authorText += " and";

              if (authors.length > 1) authorText += " ";
            }

            authorText += name;

            if (count == authors.length) authorText += ". ";
          });
        }
        else{
          var authors = this.metadata.get("origin"),
            count = 0,
            authorText = "";

          _.each(authors, function (author) {
            count++;

            if(count == 6){
                     authorText += ", et al. ";
                     return;
                   }
                   else if(count > 6)
                     return;

            if(count > 1){
                     if(authors.length > 2) authorText += ",";

              if (count == authors.length) authorText += " and";

              if (authors.length > 1) authorText += " ";
            }

            authorText += author;

            if (count == authors.length) authorText += ". ";
          });
        }
      }
      //If there is no metadata doc, then this is probably a data doc without science metadata.
      //So create the citation from the index values
      else {

        var authorText = this.model.get("rightsHolder") || this.model.get("submitter") || "",
          dateUploaded = this.model.get("dateUploaded"),
          datasource = this.model.get("datasource");
      }

      if( !this.isCollection ){
        //The author
        var authorEl = $(document.createElement("span")).addClass("author").text(authorText);

        //The publication date
        var pubDateText = "";
        if ((typeof pubDate !== "undefined") && pubDate) {
          var pubDateFormatted = new Date(pubDate).getUTCFullYear();
          if (!isNaN(pubDateFormatted)) pubDateText += pubDateFormatted;
        }
        if (dateUploaded && (isNaN(pubDateFormatted) || !pubDate)) {
          var dateUploadedFormatted = dateUploaded;
          if (!isNaN(dateUploadedFormatted)) pubDateText += dateUploadedFormatted;
        }
        var pubDateEl = $(document.createElement("span")).addClass("pubdate")

        // Only set text if we have a non-zero-length pubDate string
        if (pubDateText.length > 0) {
          pubDateEl.text(pubDateText + ". ");
        }

        //The publisher (source member node)
        var publisherText = "";
        if (typeof datasource !== "undefined" && datasource) {
          var memberNode = MetacatUI.nodeModel.getMember(datasource);

          if(memberNode)
              publisherText = memberNode.name + ". ";
            else
              publisherText = datasource + ". ";
        }
        else{
          var memberNode = MetacatUI.nodeModel.getMember(MetacatUI.nodeModel.get("currentMemberNode"));

          if(memberNode)
              publisherText = memberNode.name + ". ";
        }


        var publisherEl = $(document.createElement("span")).addClass('publisher');

        // Only set text if we have a non-zero-length publisherText string
        if (publisherText) {
          publisherEl.text(publisherText);
        }
      }
      //Collections will get the collection class added
      else{
        this.$el.addClass("collection");
      }

      if(this.model.type == "CitationModel") {
        // displaying decoded source url
        var idEl = $(document.createElement("span")).addClass("publisher-id");
        idEl.append(decodeURIComponent(sourceUrl), $(document.createElement("span")).text(". "));
      }
      else {
        //The ID
        var idEl = this.createIDElement();
      }

      var model = this.metadata || this.model,
          id = model.get("id"),
          seriesId = model.get("seriesId");

      if ((typeof title !== "undefined") && title){
        if(title.trim().charAt(title.length-1) != ".")
          title = title.trim() + ". ";
        else
          title = title.trim() + " ";

        if(this.model.type == "CitationModel") {
          // Appending the title as a link
          var titleEl = $(document.createElement("a"))
                        .addClass("metrics-route-to-metadata")
                        .attr("data-id", id)
                        .attr("href", sourceUrl)
                        .attr("target", "_blank")
                        .append(title);
        }
        else {
          var titleEl = $(document.createElement("span"))
                        .addClass("title")
                        .attr("data-id", this.metadata.get("id"))
                        .text(title);
        }

      }
      else
        var titleEl = document.createElement("span");

      //Create a link and put all the citation parts together
      if (this.createLink){
        if(this.model.type == "CitationModel") {

          // Creating a volume element to display in Citations Modal Window
          if(volume === "NULL") {
            var volumeText = "";
          }
          else {
            var volumeText = "Vol. " + volume + ". ";
          }
          var volumeEl = $(document.createElement("span")).addClass("publisher").text(volumeText);

          // Creating a 'pages' element to display in Citations Modal Window
          if(page === "NULL") {
            var pageText = "";
          }
          else {
            var pageText = "pp. " + page + ". ";
          }
          var pageEl = $(document.createElement("span")).addClass("publisher").text(pageText);

          var datasetLinkEl = $(document.createElement("span"))
                              .text("Cites Data: ");

          // Generate links for the cited datasets
          var citationMetadataCounter = 0;
          if (citationMetadata != undefined) {
            for (var key in citationMetadata) {
              citationMetadataCounter += 1;
  
              var commaSeperator = (citationMetadataCounter < Object.keys(citationMetadata).length) ? "," : ".";
  
              var mdPID = key, mdAuthorText = "", additionalAuthors = "", mdText = "", mdDateText = "";
  
              // Display first author in the dataset link
              if (citationMetadata[key]["origin"] != undefined && Array.isArray(citationMetadata[key]["origin"])) {
                mdAuthorText = citationMetadata[key]["origin"][0];
                additionalAuthors = citationMetadata[key]["origin"].length > 1 ? " et al." : "";
  
                mdText = "(" + mdAuthorText + additionalAuthors + " ";
              }
  
              // save the date
              if (citationMetadata[key]["datePublished"] != undefined) {
                mdDateText = (citationMetadata[key]["datePublished"]).slice(0,4);
                if (mdText.length == 0) {
                  mdText = "(";
                }
                mdText += mdDateText;
              }
              else if (citationMetadata[key]["dateUpdated"] != undefined) {
                mdDateText = (citationMetadata[key]["dateUpdated"]).slice(0,4);
                if (mdText.length == 0) {
                  mdText = "(";
                }
                mdText += mdDateText;
              }
              else if (citationMetadata[key]["dateModified"] != undefined) {
                mdDateText = (citationMetadata[key]["dateModified"]).slice(0,4);
                if (mdText.length == 0) {
                  mdText = "(";
                }
                mdText += mdDateText;
              }
  
              // retrieve the PID
              if (citationMetadata[key]["id"] != undefined) {
                mdPID = citationMetadata[key]["id"];
              }
              else if (key.startsWith("10."))
              {
                mdPID = "doi:" + key
              }
  
              if (mdText.length > 0) {
                mdText += ")" + commaSeperator + " ";
  
                var targetLinkEl = $(document.createElement("a"))
                          .addClass("metrics-route-to-metadata")
                          .attr("data-id", key)
                          .attr("href", MetacatUI.root + "/view/" + encodeURIComponent(mdPID))
                          .attr("target", "_blank")
                          .text(mdText);
  
                datasetLinkEl.append(targetLinkEl);
              }
  
            }
          }

          // creating citation display string
          var linkEl = $(document.createElement("span"))
                  .append(authorEl, pubDateEl, titleEl, publisherEl, volumeEl, pageEl, idEl);
                            
        }
        else {

          var linkEl = $(document.createElement("a"))
                  .addClass("route-to-metadata")
                  .attr("data-id", id)
                  .attr("href", this.metadata.createViewURL())
                  .append(authorEl, pubDateEl, titleEl, publisherEl, idEl);
        }

        this.$el.append(linkEl);

        // Only append the citation link when we have non-zero datasets
        // Append the cited dataset text to the link element
        if ( datasetLinkEl !== "undefined" && citationMetadataCounter > 0) {
          // Displaying the cites data on the new line
          this.$el.append("<br>");
          this.$el.append(datasetLinkEl);
        }
      }
      else if(this.createTitleLink){

        var linkEl = $(document.createElement("a"))
                .addClass("route-to-metadata")
                .attr("data-id", seriesId)
                .attr("href", this.metadata.createViewURL())
                .append(titleEl);
        this.$el.append(authorEl, pubDateEl, linkEl, publisherEl, idEl);
      }
      else{
        this.$el.append(authorEl, pubDateEl, titleEl, publisherEl, idEl);
      }

      this.setUpListeners();

      return this;
    },

    createIDElement: function(){

      var model      = this.metadata || this.model,
        id        = model.get("id"),
        seriesId     = model.get("seriesId"),
        datasource   = model.get("datasource");

      var idEl = $(document.createElement("span")).addClass("id");
      if(seriesId){
        //Create a link for the identifier if it is a DOI
        if( model.isDOI(seriesId) && !this.createLink ){
          var doiURL  = this.createDoiUrl(seriesId),
              doiLink = $(document.createElement("a"))
                          .attr("href", doiURL)
                          .text(seriesId);

      // Begin PANGAEA-specific override 1 (this is temporary)
          // If this is a PENGAEA dataset with a seriesId, then don't show the pid.
          if (typeof datasource !== "undefined" && datasource === "urn:node:PANGAEA") {
            idEl.append(doiLink, $(document.createElement("span")).text(". "));
          }
          // End PANGAEA-specific override 1
          else{
            idEl.append(doiLink, $(document.createElement("span")).text(", version: "));
          }
        }
        else{
          // Begin PANGAEA-specific override 2 (this is temporary)
          // If this is a PENGAEA dataset with a seriesId, then don't show the pid.
          if (typeof datasource !== "undefined" && datasource === "urn:node:PANGAEA") {
            idEl.html($(document.createElement("span")).text(seriesId + ". "));
          }
          // End PANGAEA-specific override 2
          else{
            idEl.html($(document.createElement("span")).text(seriesId + ", version: "));
          }
        }
      }

      // Begin PANGAEA-specific override 3 (this is temporary)
      // If this is a PENGAEA dataset with a seriesId, then don't show the pid. Return now.
      if(typeof datasource !== "undefined" && datasource === "urn:node:PANGAEA" && seriesId){
        return idEl;
      }
      // End PANGAEA-specific override 3
      else if( model.isDOI(id) && !this.createLink ){
        var doiURL  = this.createDoiUrl(id),
            doiLink = $(document.createElement("a"))
                        .attr("href", doiURL)
                        .text(id);

        idEl.append(doiLink, $(document.createElement("span")).text(". "));
      }
      else{
        idEl.append($(document.createElement("span")).text(id + ". "));
      }

      return idEl;
    },

    createDoiUrl: function(doi){

      if( doi.indexOf("http") == 0 ){
        return doi;
      }
      else if( doi.indexOf("doi:") == 0){
        return "https://doi.org/" + doi.substring(4);
      }
      else{
        return "https://doi.org/" + doi;
      }

    },

    setUpListeners: function(){
      if (!this.metadata) return;

      this.stopListening();

      //If anything in the model changes, rerender this citation
      this.listenTo(this.metadata, "change:origin change:creator change:pubDate change:dateUploaded change:title change:seriesId change:id change:datasource", this.render);

      //If this model is an EML211 model, then listen differently
      if(this.metadata.type == "EML"){
        var creators = this.metadata.get("creator");

        //Listen to the names
        for(var i=0; i<creators.length; i++){
          this.listenTo(creators[i], "change:individualName change:organizationName change:positionName", this.render);
        }

      }
    },

    routeToMetadata: function(e){
      var id = this.model.get("id");

      //If the user clicked on a download button or any element with the class 'stop-route', we don't want to navigate to the metadata
      if ($(e.target).hasClass('stop-route') || (typeof id === "undefined") || !id)
        return;

      MetacatUI.uiRouter.navigate('view/' + encodeURIComponent(id), {trigger: true});
    }
  });

  return CitationView;
});