CORE-POS/IS4C

#region License
// Copyright (c) 2007 James Newton-King
//
// Permission is hereby granted, free of charge, to any person
// obtaining a copy of this software and associated documentation
// files (the "Software"), to deal in the Software without
// restriction, including without limitation the rights to use,
// copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following
// conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
// OTHER DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Collections.Generic;
using System.Globalization;

namespace Newtonsoft.Json.Utilities
{
    internal class BidirectionalDictionary<TFirst, TSecond>
    {
        private readonly IDictionary<TFirst, TSecond> _firstToSecond;
        private readonly IDictionary<TSecond, TFirst> _secondToFirst;
        private readonly string _duplicateFirstErrorMessage;
        private readonly string _duplicateSecondErrorMessage;

        public BidirectionalDictionary()
            : this(EqualityComparer<TFirst>.Default, EqualityComparer<TSecond>.Default)
        {
        }

        public BidirectionalDictionary(IEqualityComparer<TFirst> firstEqualityComparer, IEqualityComparer<TSecond> secondEqualityComparer)
            : this(
                firstEqualityComparer,
                secondEqualityComparer,
                "Duplicate item already exists for '{0}'.",
                "Duplicate item already exists for '{0}'.")
        {
        }

        public BidirectionalDictionary(IEqualityComparer<TFirst> firstEqualityComparer, IEqualityComparer<TSecond> secondEqualityComparer,
            string duplicateFirstErrorMessage, string duplicateSecondErrorMessage)
        {
            _firstToSecond = new Dictionary<TFirst, TSecond>(firstEqualityComparer);
            _secondToFirst = new Dictionary<TSecond, TFirst>(secondEqualityComparer);
            _duplicateFirstErrorMessage = duplicateFirstErrorMessage;
            _duplicateSecondErrorMessage = duplicateSecondErrorMessage;
        }

        public void Set(TFirst first, TSecond second)
        {
            TFirst existingFirst;
            TSecond existingSecond;

            if (_firstToSecond.TryGetValue(first, out existingSecond))
            {
                if (!existingSecond.Equals(second))
                    throw new ArgumentException(_duplicateFirstErrorMessage.FormatWith(CultureInfo.InvariantCulture, first));
            }

            if (_secondToFirst.TryGetValue(second, out existingFirst))
            {
                if (!existingFirst.Equals(first))
                    throw new ArgumentException(_duplicateSecondErrorMessage.FormatWith(CultureInfo.InvariantCulture, second));
            }

            _firstToSecond.Add(first, second);
            _secondToFirst.Add(second, first);
        }

        public bool TryGetByFirst(TFirst first, out TSecond second)
        {
            return _firstToSecond.TryGetValue(first, out second);
        }

        public bool TryGetBySecond(TSecond second, out TFirst first)
        {
            return _secondToFirst.TryGetValue(second, out first);
        }
    }
}