//-----------------------------------------------------------------------
// -----------------------------------------------------------------------
// file="Counter"
// Project: StgSharp
// AuthorGroup: Nitload Space
// Copyright (c) Nitload Space. All rights reserved.
//     
// 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.
//     
// -----------------------------------------------------------------------
// -----------------------------------------------------------------------
using System;
using System.Numerics;

namespace StgSharp
{
    public class Counter<T> where T: unmanaged, INumber<T>
    {

        internal dynamic _value;
        internal readonly T _defaultDecrement;

        internal readonly T _defaultIncrement;
        internal readonly T _defaultValue;

        public Counter(T defaultValue, T defaultIncrement, T defaultDecrement)
        {
            _value = defaultValue;
            _defaultValue = defaultValue;
            _defaultIncrement = defaultIncrement;
            _defaultDecrement = defaultDecrement;
        }

        public T DecrementSpan => _defaultDecrement;

        public T IncrementSpan => _defaultIncrement;

        public T CurrentSpan => _value - _defaultValue;

        public T Value
        {
            get => _value;
            set => _value = value;
        }

        public void Add(T value)
        {
            _value += value;
        }

        public void QuickAdd()
        {
            _value += _defaultIncrement;
        }

        public void QuickSub()
        {
            _value -= _defaultDecrement;
        }

        public void Reset()
        {
            _value = _defaultValue;
        }

        public void Sub(T value)
        {
            _value -= value;
        }

        public override string ToString()
        {
            return Value.ToString() ?? string.Empty;
        }

        public static Counter<T> operator --(Counter<T> counter)
        {
            counter?.QuickSub();
            return counter;
        }

        public static Counter<T> operator ++(Counter<T> counter)
        {
            counter?.QuickAdd();
            return counter;
        }

        public static implicit operator T(Counter<T> counter)
        {
            return counter switch
            {
                null => T.Zero,
                _ => counter.Value
            };
        }

    }
}