/**
 *
 * Copyright 2013 Joel Grenon
 *
 * 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.
 */
var Q = require('q'),
    redis = require('redis'),
    _ = require('lodash'),
    async = require('async'),
    moment = require('moment');

require('underscore-query');

module.exports = function(request) {
    var _this = this;
    this.log.trace(request, "Handling unsubscribe command");
    var defer = Q.defer();
    Q.nextTick(function() {

        // Look for an existing subscription for this agent
        var subscription = _.query.build( _this.eventSubscriptions ).and({"agentId":request.id}).first();
        if(subscription) {
            // Remove the specified local listener for this event
            _this.removeListener(request.event, subscription.listener(request));

            subscription.events.remove(request.event);
            if(subscription.events.length === 0)
                _this.eventSubscriptions.remove(subscription);

            _this.log.info("Agent successfully unsubscribed from event %d", request.event);
        }
        else
            _this.log.warn("Tried to unsubscribe a missing subscription. Nothing was done");

        defer.resolve({success:true});
    });

    return defer.promise;
};