Source: src/js/collections/Filters.js

define([
  "jquery",
  "underscore",
  "backbone",
  "models/filters/Filter",
  "models/filters/BooleanFilter",
  "models/filters/ChoiceFilter",
  "models/filters/DateFilter",
  "models/filters/NumericFilter",
  "models/filters/ToggleFilter",
  "models/filters/SpatialFilter",
], function (
  $,
  _,
  Backbone,
  Filter,
  BooleanFilter,
  ChoiceFilter,
  DateFilter,
  NumericFilter,
  ToggleFilter,
  SpatialFilter,
) {
  "use strict";

  /**
   * @class Filters
   * @classdesc A collection of Filter models that represents a full search
   * @classcategory Collections
   * @name Filters
   * @extends Backbone.Collection
   * @constructor
   */
  var Filters = Backbone.Collection.extend(
    /** @lends Filters.prototype */ {
      /**
       * The name of this type of collection
       * @type {string}
       * @since 2.25.0
       * @default "Filters"
       */
      type: "Filters",

      /**
       * If the search results must always match one of the ids in the id
       * filters, then the id filters will be added to the query with an AND
       * operator.
       * @type {boolean}
       */
      mustMatchIds: false,

      /**
       * Function executed whenever a new Filters collection is created.
       * @param
       * {Filter|BooleanFilter|ChoiceFilter|DateFilter|NumericFilter|ToggleFilter|FilterGroup[]}
       * models - Array of filter or filter group models to add to this creation
       * @param {Object} [options] -
       * @property {boolean} isUIFilterType - Set to true to indicate that these
       * filters or filterGroups are part of a UIFilterGroup (aka custom Portal
       * search filter). Otherwise, it's assumed that this model is in a
       * Collection model definition.
       * @property {XMLElement} objectDOM -  A FilterGroupType or
       * UIFilterGroupType XML element from a portal or collection document. If
       * provided, the XML will be parsed and the Filters models extracted
       * @property {boolean} catalogSearch  - If set to true, a catalog search
       * phrase will be appended to the search query that limits the results to
       * un-obsoleted metadata.
       */
      initialize: function (models, options) {
        try {
          if (typeof options === "undefined") {
            var options = {};
          }
          if (options && options.objectDOM) {
            // Models are automatically added to the collection by the parse
            // function.
            var isUIFilterType = options.isUIFilterType == true ? true : false;
            this.parse(options.objectDOM, isUIFilterType);
          }
          if (options.catalogSearch) {
            this.catalogSearchQuery = this.createCatalogSearchQuery();
          }
        } catch (error) {
          console.log(
            "Error initializing a Filters collection. Error details: " + error,
          );
        }
      },

      /**
       * Creates the type of Filter Model based on the given filter type. This
       * function is typically not called directly. It is used by Backbone.js
       * when adding a new model to the collection.
       * @param {object} attrs - A literal object that contains the attributes
       * to pass to the model
       * @property {string} attrs.filterType - The type of Filter to create
       * @property {XMLElement} attrs.objectDOM - The Filter XML
       * @param {object} options - A literal object of additional options to
       * pass to the model
       * @returns
       * {Filter|BooleanFilter|ChoiceFilter|DateFilter|NumericFilter|ToggleFilter|FilterGroup}
       */
      model: function (attrs, options) {
        // Get the model type
        var type = "";
        // If no filterType was specified, but an objectDOM exists (from parsing
        // a Collection or Portal document), get the filter type from the
        // objectDOM node name
        if (!attrs.filterType && attrs.objectDOM) {
          type = attrs.objectDOM.nodeName;
        } else if (attrs.filterType) {
          type = attrs.filterType;
        } else if (attrs.nodeName) {
          type = attrs.nodeName;
        }
        // Ignoring the case of the type allows using either the filter type
        // (e.g. BooleanFilter) or the nodeName value (e.g. "booleanFilter")
        type = type.toLowerCase();

        switch (type) {
          case "booleanfilter":
            return new BooleanFilter(attrs, options);

          case "datefilter":
            return new DateFilter(attrs, options);

          case "numericfilter":
            return new NumericFilter(attrs, options);

          case "filtergroup":
            // We must initialize a Filter Group using the inline require syntax
            // to avoid the problem of circular dependencies. Filters requires
            // Filter Groups, and Filter Groups require Filters. For more info,
            // see https://requirejs.org/docs/api.html#circular
            var FilterGroup = require("models/filters/FilterGroup");
            var newFilterGroup = new FilterGroup(attrs, options);
            return newFilterGroup;

          case "choicefilter":
            return new ChoiceFilter(attrs, options);

          case "togglefilter":
            return new ToggleFilter(attrs, options);

          case "spatialfilter":
            return new SpatialFilter(attrs, options);

          default:
            return new Filter(attrs, options);
        }
      },

      /**
       * Parses a <filterGroup> or <definition> element from a collection or
       * portal document and sets the resulting models on this collection.
       *
       *  @param {XMLElement} objectDOM - A FilterGroupType or UIFilterGroupType
       *  XML element from a portal or collection document
       *  @param {boolean} isUIFilterType - Set to true to indicate that these
       *  filters or filterGroups are part of a UIFilterGroup (aka custom Portal
       *  search filter). Otherwise, it's assumed that the filters are part of a
       *  Collection model definition.
       *  @return {JSON} The result of the parsed XML, in JSON.
       */
      parse: function (objectDOM, isUIFilterType) {
        var filters = this;

        $(objectDOM)
          .children()
          .each(function (i, filterNode) {
            filters.add({
              objectDOM: filterNode,
              isUIFilterType: isUIFilterType == true ? true : false,
            });
          });

        return filters.toJSON();
      },

      /**
       * Builds the query string to send to the query engine. Iterates over each
       * filter in the collection and adds to the query string.
       *
       * @param {string} [operator=AND] The operator to use to combine multiple
       * filters in this filter group. Must be AND or OR.
       * @return {string} The query string to send to Solr
       */
      getQuery: function (operator = "AND") {
        // The complete query string that eventually gets returned
        var completeQuery = "";

        // Ensure that the operator is AND or OR so that the query string will
        // be valid. Default to AND.
        if (typeof operator !== "string") {
          var operator = "AND";
        }
        operator = operator.toUpperCase();
        if (!["AND", "OR"].includes(operator)) {
          operator = "AND";
        }

        // Adds URI encoded spaces to either side of a string
        var padString = function (string) {
          return "%20" + string + "%20";
        };

        // Get the list of filters that use id fields since these are used
        // differently.
        var idFilters = this.getIdFilters();
        // Get the remaining filters that don't contain any ID fields
        var mainFilters = this.getNonIdFilters();

        // Create the grouped query for the id filters
        var idFilterQuery = this.getGroupQuery(idFilters, "OR");
        // Make a query for all of the filters that do not contain ID fields
        var mainQuery = this.getGroupQuery(mainFilters, operator);

        // First add the query string built from the non-ID filters
        completeQuery += mainQuery;

        // Then add the Data Catalog filters if Filters was initialized with the
        // catalogSearch = true option. Filters that are used in the data
        // catalog are treated specially
        if (this.catalogSearchQuery && this.catalogSearchQuery.length) {
          // If there are other filters besides the catalog filters, AND the
          // catalog filters to the end of the query for the other filters,
          // regardless of which operator this function uses to combine other
          // filters.
          if (completeQuery && completeQuery.trim().length) {
            completeQuery += padString("AND");
          }
          completeQuery += this.catalogSearchQuery;
        }

        // Finally, add the ID filters to the very end of the query. This is
        // done so that the query string is constructed with these filters
        // "OR"ed into the query. For example, a query might be to look for
        // datasets by a certain scientist OR with the given id. If those
        // filters were ANDed together, the search would essentially ignore the
        // creator filter and only return the dataset with the matching id.
        if (idFilterQuery && idFilterQuery.trim().length) {
          if (completeQuery && completeQuery.trim().length) {
            // If the search results must always match one of the ids in the id
            // filters, then add the id filters to the query with the AND
            // operator. This flag is set on this Collection. Otherwise, use the
            // OR operator
            var idOperator = this.mustMatchIds
              ? padString("AND")
              : padString("OR");
            completeQuery =
              "(" + completeQuery + ")" + idOperator + idFilterQuery;
          } else {
            // If the query is ONLY made of id filters, then the id filter query
            // is the complete query
            completeQuery += idFilterQuery;
          }
        }

        // Return the completed query
        return completeQuery;
      },

      /**
       * Searches the Filter models in this collection and returns any that have
       * at least one field that matches any of the ID query fields, such as by
       * id, seriesId, or the isPartOf relationship.
       * @returns
       * {Filter|BooleanFilter|ChoiceFilter|DateFilter|NumericFilter|ToggleFilter|FilterGroup[]}
       * Returns an array of filter models that include at least one ID field
       */
      getIdFilters: function () {
        try {
          return this.filter(function (filterModel) {
            if (typeof filterModel.isIdFilter == "undefined") {
              return false;
            }
            return filterModel.isIdFilter();
          });
        } catch (error) {
          console.log(
            "Error trying to find ID Filters, error details: " + error,
          );
        }
      },

      /**
       * Searches the Filter models in this collection and returns all have no
       * fields matching any of the ID query fields.
       * @returns
       * {Filter|BooleanFilter|ChoiceFilter|DateFilter|NumericFilter|ToggleFilter|FilterGroup[]}
       * Returns an array of filter models that do not include any ID fields
       */
      getNonIdFilters: function () {
        try {
          return this.difference(this.getIdFilters());
        } catch (error) {
          console.log(
            "Error trying to find non-ID Filters, error details: " + error,
          );
        }
      },

      /**
       * Get a query string for a group of Filters. The Filters will be ANDed
       * together, unless a different operator is given.
       * @param
       * {Filter|BooleanFilter|ChoiceFilter|DateFilter|NumericFilter|ToggleFilter|FilterGroup[]}
       * filterModels - The Filters to turn into a query string
       * @param {string} [operator="AND"] - The operator to use between filter
       * models
       * @return {string} The query string
       */
      getGroupQuery: function (filterModels, operator = "AND") {
        try {
          if (
            !filterModels ||
            !filterModels.length ||
            !this.getNonEmptyFilters(filterModels)
          ) {
            return "";
          }
          //Start an array to contain the query fragments
          var groupQueryFragments = [];

          //For each Filter in this group, get the query string
          _.each(
            filterModels,
            function (filterModel) {
              // Get the Solr query string from this model. Pass on the group
              // operator so that we can detect whether this filter query needs
              // a positive clause in case it has exclude set to true.
              var filterQuery = filterModel.getQuery(operator);
              //Add the filter query string to the overall array
              if (filterQuery && filterQuery.length > 0) {
                groupQueryFragments.push(filterQuery);
              }
            },
            this,
          );

          //Join this group's query fragments with an OR operator
          if (groupQueryFragments.length) {
            var queryString = groupQueryFragments.join(
              "%20" + operator + "%20",
            );
            if (groupQueryFragments.length > 1) {
              queryString = "(" + queryString + ")";
            }
            return queryString;
          }
          //Otherwise, return an empty string
          else {
            return "";
          }
        } catch (e) {
          console.log(
            "Error creating a group query, returning a blank string. ",
            e,
          );
          return "";
        }
      },

      /**
       * Given a Solr field name, determines if that field is set as a filter
       * option
       */
      filterIsAvailable: function (field) {
        var matchingFilter = this.find(function (filterModel) {
          return _.contains(filterModel.fields, field);
        });

        if (matchingFilter) {
          return true;
        } else {
          return false;
        }
      },

      /*
       * Returns an array of filter models in this collection that have a value
       * set
       *
       * @return {Array} - an array of filter models in this collection that
       * have a value set
       */
      getCurrentFilters: function () {
        var currentFilters = new Array();

        this.each(function (filterModel) {
          //If the filter model has values set differently than the default AND
          // it is not an invisible filter, then add it to the current filters
          // array
          if (
            !filterModel.get("isInvisible") &&
            ((Array.isArray(filterModel.get("values")) &&
              filterModel.get("values").length &&
              _.difference(
                filterModel.get("values"),
                filterModel.defaults().values,
              ).length) ||
              (!Array.isArray(filterModel.get("values")) &&
                filterModel.get("values") !== filterModel.defaults().values))
          ) {
            currentFilters.push(filterModel);
          }
        });

        return currentFilters;
      },

      /**
       * Get all filters in this collection that are of a given filter type.
       * @param {string} type - The filter type to get, e.g. "BooleanFilter". If
       * not set, all filters will be returned.
       * @returns {Filter[]} An array of filter models
       */
      getAllOfType: function (type) {
        if (!type) {
          return this.models;
        }
        return this.filter(function (filterModel) {
          return filterModel.get("filterType") == type;
        });
      },

      /**
       * Returns the geohash levels that are set on any SpatialFilter models in
       * this collection. If no SpatialFilter models are found, or no geohash
       * levels are set, an empty array is returned.
       * @returns {string[]} An array of geohash levels in the format
       * ["geohash_1", "geohash_2", ...]
       */
      getGeohashLevels: function () {
        const spFilters = this.getAllOfType("SpatialFilter");
        if (!spFilters.length) {
          return [];
        }
        return _.uniq(
          _.flatten(
            _.map(spFilters, function (spFilter) {
              const fields = spFilter.get("fields");
              if (fields && fields.length) {
                return _.filter(fields, function (field) {
                  return field.indexOf("geohash") > -1;
                });
              }
            }),
          ),
        );
      },

      /*
       * Clear the values of all geohash-related models in the collection
       */
      resetGeohash: function () {
        //Find all the filters in this collection that are related to geohashes
        this.each(function (filterModel) {
          if (
            !filterModel.get("isInvisible") &&
            (filterModel.type == "SpatialFilter" ||
              _.intersection(filterModel.fields, [
                "geohashes",
                "geohashLevel",
                "geohashGroups",
              ]).length)
          ) {
            filterModel.resetValue();
          }
        });
      },

      /**
       * Create a partial query string that's required for catalog searches
       * @returns {string} - Returns the query string fragment for a catalog
       * search
       */
      createCatalogSearchQuery: function () {
        var catalogFilters = new Filters([
          {
            fields: ["obsoletedBy"],
            values: ["*"],
            exclude: true,
          },
          {
            fields: ["formatType"],
            values: ["METADATA"],
            matchSubstring: false,
          },
          {
            fields: ["formatId"],
            values: ["dataone.org/collections", "dataone.org/portals"],
            exclude: true,
            matchSubstring: true,
            operator: "OR",
          },
        ]);
        var query = catalogFilters.getGroupQuery(catalogFilters.models, "AND");
        return query;
      },

      /**
       * Creates and adds a Filter to this collection that filters datasets to
       * only those that the logged-in user has permission to change permission
       * of.
       */
      addOwnershipFilter: function () {
        if (MetacatUI.appUserModel.get("loggedIn")) {
          //Filter datasets by their ownership
          this.add({
            fields: ["rightsHolder", "changePermission"],
            values: MetacatUI.appUserModel.get("allIdentitiesAndGroups"),
            operator: "OR",
            fieldsOperator: "OR",
            matchSubstring: false,
            exclude: false,
          });
        }
      },

      /**
       * Creates and adds a Filter to this collection that filters datasets to
       * only those that the logged-in user has permission to write to.
       */
      addWritePermissionFilter: function () {
        if (MetacatUI.appUserModel.get("loggedIn")) {
          //Filter datasets by their ownership
          this.add({
            fields: ["rightsHolder", "writePermission", "changePermission"],
            values: MetacatUI.appUserModel.get("allIdentitiesAndGroups"),
            operator: "OR",
            fieldsOperator: "OR",
            matchSubstring: false,
            exclude: false,
          });
        }
      },

      /**
       * Removes Filter models from this collection if they match the given
       * field
       * @param {string} field - The field whose matching filters that should be
       * removed from this collection
       */
      removeFiltersByField: function (field) {
        var toRemove = [];

        this.each(function (filter) {
          if (filter.get && filter.get("fields").includes(field)) {
            toRemove.push(filter);
          }
        });

        this.remove(toRemove);
      },

      /**
       * Remove filters from the collection that are lacking fields, values, and
       * in the case of a numeric filter, a min and max value.
       * @param {boolean} [recursive=false] - Set to true to also remove empty
       * filters from within any and all nested filterGroups.
       */
      removeEmptyFilters: function (recursive = false) {
        try {
          var toRemove = this.difference(this.getNonEmptyFilters());
          this.remove(toRemove);

          if (recursive) {
            var nestedGroups = this.filter(function (filterModel) {
              return filterModel.type == "FilterGroup";
            });

            if (nestedGroups) {
              nestedGroups.forEach(function (filterGroupModel) {
                filterGroupModel.get("filters").removeEmptyFilters(true);
              });
            }
          }
        } catch (e) {
          console.log(
            "Failed to remove empty Filter models from the Filters collection, error message: " +
              e,
          );
        }
      },

      /**
       * getNonEmptyFilters - Returns the array of filters that are not empty
       * @return
       * {Filter|BooleanFilter|ChoiceFilter|DateFilter|NumericFilter|ToggleFilter|FilterGroup[]}
       * returns an array of Filter or FilterGroup models that are not empty
       */
      getNonEmptyFilters: function () {
        try {
          return this.filter(function (filterModel) {
            return !filterModel.isEmpty();
          });
        } catch (e) {
          console.log(
            "Failed to remove empty Filter models from the Filters collection, error message: " +
              e,
          );
        }
      },

      /**
       * Remove a Filter from the Filters collection silently, and replace it
       * with a new model.
       *
       * @param  {Filter} model    The model to replace
       * @param  {object} newAttrs Attributes for the replacement model. Use the
       * filterType attribute to replace with a different type of Filter.
       * @return {Filter}          Returns the replacement Filter model, which
       * is already part of the Filters collection.
       */
      replaceModel: function (model, newAttrs) {
        try {
          var index = this.indexOf(model),
            oldModelId = model.cid;

          this.remove(oldModelId, { silent: true });

          var newModel = this.add(newAttrs, { at: index });

          return newModel;
        } catch (e) {
          console.log(
            "Failed to replace a Filter model in a Filters collection, " + e,
          );
        }
      },

      /**
       * visibleIndexOf - Get the index of a given model, excluding any filters
       * that are marked as invisible.
       *
       * @param  {Filter|BooleanFilter|NumericFilter|DateFilter} model The
       * filter model for which to get the visible index
       * @return {number} An integer representing the filter model's position in
       * the list of visible filters.
       */
      visibleIndexOf: function (model) {
        try {
          // Don't count invisible filters in the index we display to the user
          var visibleFilters = this.filter(function (filterModel) {
            var isInvisible = filterModel.get("isInvisible");
            return typeof isInvisible == "undefined" || isInvisible === false;
          });
          return _.indexOf(visibleFilters, model);
        } catch (e) {
          console.log(
            "Failed to get the index of a Filter within the collection of visible Filters, error message: " +
              e,
          );
        }
      },
    },
  );
  return Filters;
});