// Copyright (C) Stichting Deltares 2025. All rights reserved.
// 
// This file is part of the Dam Engine.
// 
// The Dam Engine is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
// 
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
// 
// All names, logos, and references to "Deltares" are registered trademarks of
// Stichting Deltares and remain full property of Stichting Deltares at all times.
// All rights reserved.

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;

namespace Deltares.DamEngine.Calculators.KernelWrappers.MacroStabilityCommon.MacroStabilityIo;

/// <summary>
/// Class providing methods to register objects.
/// </summary>
internal class ObjectRegistry
{
    private readonly ConcurrentDictionary<object, int> objects = new ConcurrentDictionary<object, int>();
    private int currentId;

    /// <summary>
    /// <summary>Gets an unique id of an object based on its instance.</summary>
    /// </summary>
    /// <param name="object">The object to get the id from.</param>
    /// <returns>The id.</returns>
    /// <exception cref="ArgumentNullException">Thrown when <paramref name="object"/> is <c>null</c>.</exception>
    public int GetId(object @object)
    {
        AddsObjectToRegistryIfNotExistsInRegistry(@object);
        return objects[@object];
    }

    /// <summary>
    /// <summary>Gets an object from an id.</summary>
    /// </summary>
    /// <param name="id">The id to get the object from.</param>
    /// <returns>The object of <c>null</c> if not exists.</returns>
    /// <exception cref="InvalidOperationException">Thrown when <paramref name="id"/> is not valid.</exception>
    public object GetObject(int id)
    {
        return objects.First((Func<KeyValuePair<object, int>, bool>) (x => x.Value == id)).Key;
    }

    private void AddsObjectToRegistryIfNotExistsInRegistry(object @object)
    {
        if (IsObjectInRegistry(@object))
        {
            return;
        }

        AddObjectToRegistry(@object);
    }

    private bool IsObjectInRegistry(object @object) => objects.ContainsKey(@object);

    private void AddObjectToRegistry(object @object)
    {
        objects.AddOrUpdate(@object, currentId, (Func<object, int, int>) ((o, i) => objects.Count + 1));
        ++currentId;
    }
}