Move sorting logic from table to list.

chrome/browser/resources/shared/js/cr/ui/table/table_data_model.js

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-/**
- * @fileoverview This is a table data model
- */
-cr.define('cr.ui.table', function() {
-  const EventTarget = cr.EventTarget;
-  const Event = cr.Event;
-  const ArrayDataModel = cr.ui.ArrayDataModel;
-
-  /**
-   * A table data model that supports sorting by storing initial indexes of
-   * elements for each position in sorted array.
-   * @param {!Array} items The underlying array.
-   * @constructor
-   * @extends {ArrayDataModel}
-   */
-  function TableDataModel(items) {
-    ArrayDataModel.apply(this, arguments);
-    this.indexes_ = [];
-    for (var i = 0; i < items.length; i++) {
-      this.indexes_.push(i);
-    }
-  }
-
-  TableDataModel.prototype = {
-    __proto__: ArrayDataModel.prototype,
-
-    /**
-     * Returns the item at the given index.
-     * This implementation returns the item at the given index in the source
-     * array before sort.
-     * @param {number} index The index of the element to get.
-     * @return {*} The element at the given index.
-     */
-    getItemByUnsortedIndex_: function(unsortedIndex) {
-      return ArrayDataModel.prototype.item.call(this, unsortedIndex);
-    },
-
-    /**
-     * Returns the item at the given index.
-     * This implementation returns the item at the given index in the sorted
-     * array.
-     * @param {number} index The index of the element to get.
-     * @return {*} The element at the given index.
-     */
-    item: function(index) {
-      if (index >= 0 && index < this.length)
-        return this.getItemByUnsortedIndex_(this.indexes_[index]);
-      return undefined;
-    },
-
-    /**
-     * Returns compare function set for given field.
-     * @param {string} field The field to get compare function for.
-     * @return {Function(*, *): number} Compare function set for given field.
-     */
-    compareFunction: function(field) {
-      return this.compareFunctions_[field];
-    },
-
-    /**
-     * Sets compare function for given field.
-     * @param {string} field The field to set compare function.
-     * @param {Function(*, *): number} Compare function to set for given field.
-     */
-    setCompareFunction: function(field, compareFunction) {
-      this.compareFunctions_[field] = compareFunction;
-    },
-
-    /**
-     * Returns current sort status.
-     * @return {!Object} Current sort status.
-     */
-    get sortStatus() {
-      if (this.sortStatus_) {
-        return this.createSortStatus(
-            this.sortStatus_.field, this.sortStatus_.direction);
-      } else {
-        return this.createSortStatus(null, null);
-      }
-    },
-
-    /**
-     * This removes and adds items to the model.
-     * This dispatches a splice event.
-     * This implementation runs sort after splice and creates permutation for
-     * the whole change.
-     * @param {number} index The index of the item to update.
-     * @param {number} deleteCount The number of items to remove.
-     * @param {...*} The items to add.
-     * @return {!Array} An array with the removed items.
-     */
-    splice: function(index, deleteCount, var_args) {
-      var addCount = arguments.length - 2;
-      var newIndexes = [];
-      var deletePermutation = [];
-      var deleted = 0;
-      for (var i = 0; i < this.indexes_.length; i++) {
-        var oldIndex = this.indexes_[i];
-        if (oldIndex < index) {
-          newIndexes.push(oldIndex);
-          deletePermutation.push(i - deleted);
-        } else if (oldIndex >= index + deleteCount) {
-          newIndexes.push(oldIndex - deleteCount + addCount);
-          deletePermutation.push(i - deleted);
-        } else {
-          deletePermutation.push(-1);
-          deleted++;
-        }
-      }
-      for (var i = 0; i < addCount; i++) {
-        newIndexes.push(index + i);
-      }
-      this.indexes_ = newIndexes;
-
-      var rv = ArrayDataModel.prototype.splice.apply(this, arguments);
-
-      var splicePermutation;
-      if (this.sortStatus.field) {
-        var sortPermutation = this.doSort_(this.sortStatus.field,
-                                           this.sortStatus.direction);
-        splicePermutation = deletePermutation.map(function(element) {
-          return element != -1 ? sortPermutation[element] : -1;
-        });
-      } else {
-        splicePermutation = deletePermutation;
-      }
-      this.dispatchSortEvent_(splicePermutation);
-
-      return rv;
-    },
-
-    /**
-     * Use this to update a given item in the array. This does not remove and
-     * reinsert a new item.
-     * This dispatches a change event.
-     * This implementation runs sort after updating.
-     * @param {number} index The index of the item to update.
-     */
-    updateIndex: function(index) {
-      ArrayDataModel.prototype.updateIndex.apply(this, arguments);
-
-      if (this.sortStatus.field)
-        this.sort(this.sortStatus.field, this.sortStatus.direction);
-    },
-
-    /**
-     * Creates sort status with given field and direction.
-     * @param {string} field Sort field.
-     * @param {string} direction Sort direction.
-     * @return {!Object} Created sort status.
-     */
-    createSortStatus: function(field, direction) {
-      return {
-        field: field,
-        direction: direction
-      };
-    },
-
-    /**
-     * Called before a sort happens so that you may fetch additional data
-     * required for the sort.
-     *
-     * @param {string} field Sort field.
-     * @param {function()} callback The function to invoke when preparation
-     *     is complete.
-     */
-    prepareSort: function(field, callback) {
-      callback();
-    },
-
-    /**
-     * Sorts data model according to given field and direction and dispathes
-     * sorted event.
-     * @param {string} field Sort field.
-     * @param {string} direction Sort direction.
-     */
-    sort: function(field, direction) {
-      var self = this;
-
-      this.prepareSort(field, function() {
-        var sortPermutation = self.doSort_(field, direction);
-        self.dispatchSortEvent_(sortPermutation);
-      });
-    },
-
-    /**
-     * Sorts data model according to given field and direction.
-     * @param {string} field Sort field.
-     * @param {string} direction Sort direction.
-     */
-    doSort_: function(field, direction) {
-      var compareFunction = this.sortFunction_(field, direction);
-      var positions = [];
-      for (var i = 0; i < this.length; i++) {
-        positions[this.indexes_[i]] = i;
-      }
-      this.indexes_.sort(compareFunction);
-      this.sortStatus_ = this.createSortStatus(field, direction);
-      var sortPermutation = [];
-      for (var i = 0; i < this.length; i++) {
-        sortPermutation[positions[this.indexes_[i]]] = i;
-      }
-      return sortPermutation;
-    },
-
-    dispatchSortEvent_: function(sortPermutation) {
-      var e = new Event('sorted');
-      e.sortPermutation = sortPermutation;
-      this.dispatchEvent(e);
-    },
-
-    /**
-     * Creates compare function for the field.
-     * Returns the function set as sortFunction for given field
-     * or default compare function
-     * @param {string} field Sort field.
-     * @param {Function(*, *): number} Compare function.
-     */
-    createCompareFunction_: function(field) {
-      var compareFunction =
-          this.compareFunctions_ ? this.compareFunctions_[field] : null;
-      var defaultValuesCompareFunction = this.defaultValuesCompareFunction;
-      if (compareFunction) {
-        return compareFunction;
-      } else {
-        return function(a, b) {
-          return defaultValuesCompareFunction.call(null, a[field], b[field]);
-        }
-      }
-      return compareFunction;
-    },
-
-    /**
-     * Creates compare function for given field and direction.
-     * @param {string} field Sort field.
-     * @param {string} direction Sort direction.
-     * @param {Function(*, *): number} Compare function.
-     */
-    sortFunction_: function(field, direction) {
-      var compareFunction = this.createCompareFunction_(field);
-      var dirMultiplier = direction == 'desc' ? -1 : 1;
-
-      return function(index1, index2) {
-        var item1 = this.getItemByUnsortedIndex_(index1);
-        var item2 = this.getItemByUnsortedIndex_(index2);
-
-        var compareResult = compareFunction.call(null, item1, item2);
-        if (compareResult != 0)
-          return dirMultiplier * compareResult;
-        return dirMultiplier * this.defaultValuesCompareFunction(index1,
-                                                                 index2);
-      }.bind(this);
-    },
-
-    /**
-     * Default compare function.
-     */
-    defaultValuesCompareFunction: function(a, b) {
-      // We could insert i18n comparisons here.
-      if (a < b)
-        return -1;
-      if (a > b)
-        return 1;
-      return 0;
-    }
-  };
-
-  return {
-    TableDataModel: TableDataModel
-  };
-});