/* Copyright 2010-present MongoDB Inc.
*
* 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.
*/

using System;
using MongoDB.Bson.Serialization.Options;
using MongoDB.Bson.Serialization.Serializers;

namespace MongoDB.Bson.Serialization.Attributes
{
    /// <summary>
    /// Specifies the external representation and related options for this field or property.
    /// </summary>
    [AttributeUsage(AttributeTargets.Property | AttributeTargets.Field)]
    public class BsonTimeSpanOptionsAttribute : BsonSerializationOptionsAttribute
    {
        // private fields
        private BsonType _representation;
        private TimeSpanUnits _units;

        // constructors
        /// <summary>
        /// Initializes a new instance of the BsonTimeSpanOptionsAttribute class.
        /// </summary>
        /// <param name="representation">The external representation.</param>
        public BsonTimeSpanOptionsAttribute(BsonType representation)
        {
            _representation = representation;
        }

        /// <summary>
        /// Initializes a new instance of the BsonTimeSpanOptionsAttribute class.
        /// </summary>
        /// <param name="representation">The external representation.</param>
        /// <param name="units">The TimeSpanUnits.</param>
        public BsonTimeSpanOptionsAttribute(BsonType representation, TimeSpanUnits units)
        {
            _representation = representation;
            _units = units;
        }

        // public properties
        /// <summary>
        /// Gets the external representation.
        /// </summary>
        public BsonType Representation
        {
            get { return _representation; }
        }

        /// <summary>
        /// Gets or sets the TimeSpanUnits.
        /// </summary>
        public TimeSpanUnits Units
        {
            get { return _units; }
            set { _units = value; }
        }

        // protected methods
        /// <summary>
        /// Reconfigures the specified serializer by applying this attribute to it.
        /// </summary>
        /// <param name="serializer">The serializer.</param>
        /// <returns>A reconfigured serializer.</returns>
        protected override IBsonSerializer Apply(IBsonSerializer serializer)
        {
            var timeSpanSerializer = serializer as TimeSpanSerializer;
            if (timeSpanSerializer != null)
            {
                return timeSpanSerializer.WithRepresentation(_representation, _units);
            }

            return base.Apply(serializer);
        }
    }
}