/*****************************************************************************
 * Open MCT Web, Copyright (c) 2014-2015, United States Government
 * as represented by the Administrator of the National Aeronautics and Space
 * Administration. All rights reserved.
 *
 * Open MCT Web is licensed under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0.
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 * Open MCT Web includes source code licensed under additional open source
 * licenses. See the Open Source Licenses file (LICENSES.md) included with
 * this source code distribution or the Licensing information page available
 * at runtime from the About dialog for additional information.
 *****************************************************************************/
/*global define*/

define(
    function () {
        "use strict";

        /**
         * Policy preventing the Plot view from being made available for
         * domain objects which have non-numeric telemetry.
         * @implements {Policy}
         */
        function PlotViewPolicy() {
            function hasImageTelemetry(domainObject) {
                var telemetry = domainObject &&
                        domainObject.getCapability('telemetry'),
                    metadata = telemetry ? telemetry.getMetadata() : {},
                    ranges = metadata.ranges || [];

                // Generally, we want to allow Plot for telemetry-providing
                // objects (most telemetry is plottable.) We only want to
                // suppress this for telemetry which only has explicitly
                // non-numeric values.
                return ranges.length === 0 || ranges.some(function (range) {
                    // Assume format is numeric if it is undefined
                    // (numeric telemetry is the common case)
                    return range.format === undefined ||
                            range.format === 'number';
                });
            }

            return {
                allow: function (view, domainObject) {
                    if (view.key === 'plot') {
                        return hasImageTelemetry(domainObject);
                    }

                    return true;
                }
            };
        }

        return PlotViewPolicy;
    }
);