//
// Copyright (c) 2014 Piotr Fusik <piotr@fusik.info>
//
// 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.
//
// 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 OWNER 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.
//

using System;

namespace Sooda.QL
{
    public enum SoqlStringContainsPosition
    {
        Start,
        End,
        Any
    }

    public class SoqlStringContainsExpression : SoqlBooleanExpression
    {
        public readonly SoqlExpression haystack;
        public readonly SoqlStringContainsPosition position;
        public readonly string needle;

        public SoqlStringContainsExpression(SoqlExpression haystack, SoqlStringContainsPosition position, string needle)
        {
            this.haystack = haystack;
            this.position = position;
            this.needle = needle;
        }

        // visitor pattern
        public override void Accept(ISoqlVisitor visitor)
        {
            visitor.Visit(this);
        }

        public override object Evaluate(ISoqlEvaluateContext context)
        {
            object val = haystack.Evaluate(context);
            if (val == null)
                return null;
            string s = (string) val;

            switch (position)
            {
                case SoqlStringContainsPosition.Start:
                    return s.StartsWith(needle);
                case SoqlStringContainsPosition.End:
                    return s.EndsWith(needle);
                case SoqlStringContainsPosition.Any:
                    return s.Contains(needle);
            }

            throw new NotImplementedException(position.ToString());
        }
    }

}
