//Copyright 2010 Microsoft Corporation
//
//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.

namespace System.Data.Services.Common
{
    using System;
    using System.Collections.ObjectModel;
    using System.Data.Services.Client;
    using System.Linq;

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1019:DefineAccessorsForAttributeArguments", Justification = "Accessors are available for processed input.")]
    [AttributeUsage(AttributeTargets.Class, AllowMultiple = false)]
    public sealed class DataServiceKeyAttribute : System.Attribute
    {
        private readonly ReadOnlyCollection<string> keyNames;

        public DataServiceKeyAttribute(string keyName)
        {
            Util.CheckArgumentNull(keyName, "keyName");
            Util.CheckArgumentNotEmpty(keyName, "KeyName");
            this.keyNames = new ReadOnlyCollection<string>(new string[1] { keyName });
        }

        public DataServiceKeyAttribute(params string[] keyNames)
        {
            Util.CheckArgumentNull(keyNames, "keyNames");
            if (keyNames.Length == 0 || keyNames.Any(f => f == null || f.Length == 0))
            {
                throw Error.Argument(Strings.DSKAttribute_MustSpecifyAtleastOnePropertyName, "keyNames");
            }

            this.keyNames = new ReadOnlyCollection<string>(keyNames);
        }

        public ReadOnlyCollection<string> KeyNames
        {
            get
            {
                return this.keyNames;
            }
        }
    }
}