// Copyright (c) 2012, Event Store LLP
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
// 
// Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// Neither the name of the Event Store LLP nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// 

namespace EventStore.Projections.Core.Standard
{
    public class StreamCategoryExtractorByLastSeparator : StreamCategoryExtractor
    {
        private readonly char _separator;

        public StreamCategoryExtractorByLastSeparator(char separator)
        {
            _separator = separator;
        }

        public override string GetCategoryByStreamId(string streamId)
        {
            string category = null;
            if (!streamId.StartsWith("$"))
            {
                var lastSeparatorPosition = streamId.LastIndexOf(_separator);
                if (lastSeparatorPosition > 0)
                    category = streamId.Substring(0, lastSeparatorPosition);
            }
            return category;
        }
    }
}
