// Copyright (C) Stichting Deltares 2017. All rights reserved.
//
// This file is part of the Macro Stability kernel.
//
// The Macro Stability kernel 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;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;

namespace Deltares.DamEngine.Data.Standard
{
    /// <summary>
    /// Static class ObjectExtensions
    /// </summary>
    public static class ObjectExtensions
    {
        private const double threshold = 0.0000001;

        /// <summary>
        /// Tests two double values for equality with a default precision of 
        /// </summary>
        /// <param name="double1">The first double value</param>
        /// <param name="double2">The other double value to compare with</param>
        /// <returns>True when almost equal</returns>
        public static bool AlmostEquals(this double double1, double double2)
        {
            return AlmostEquals(double1, double2, threshold);
        }

        /// <summary>
        /// Tests two double values for equality with a given precision
        /// </summary>
        /// <param name="double1">The first double value</param>
        /// <param name="double2">The other double value to compare with</param>
        /// <param name="precision">The precision value </param>
        /// <returns>True when almost equal</returns>
        public static bool AlmostEquals(this double double1, double double2, double precision)
        {
            if (double.IsNaN(double1) && double.IsNaN(double2))
            {
                return true;
            }

            if (double.IsNaN(double1) || double.IsNaN(double2))
            {
                return false;
            }

            return (Math.Abs(double1 - double2) <= precision);
        }

        /// <summary>  
        /// Clone properties from an original object to a destination object.  
        /// </summary>  
        /// <remarks>
        /// Copy matching properties from object to object
        /// http://goneale.wordpress.com/2009/02/16/cloning-object-properties-via-reflection/#
        /// </remarks>
        /// <typeparam name="T1"></typeparam>  
        /// <typeparam name="T2"></typeparam>  
        /// <param name="origin"></param>  
        /// <param name="destination"></param>
        /// <param name="excludedProperties"></param>  
        public static void CloneProperties<T1, T2>(this T1 origin, T2 destination, params string[] excludedProperties)
        {
            // Instantiate if necessary  
            if (destination == null)
            {
                throw new ArgumentNullException("destination", "Destination object must first be instantiated.");
            }
            // Loop through each property in the destination  
            foreach (var destinationProperty in destination.GetType().GetProperties())
            {
                bool excluded = false;
                foreach (var excludedProperty in excludedProperties)
                {
                    if (excludedProperty.ToLower().Equals(destinationProperty.Name.ToLower()))
                    {
                        excluded = true;
                    }
                }

                if (excluded || IsIList(destinationProperty) || IsIDictionary(destinationProperty)
                    || IsGenericIList(destinationProperty) || IsGenericIDictionary(destinationProperty))
                {
                    continue;
                }
                // find and set val if we can find a matching property name and matching type in the origin with the origin's value  
                if (!origin.Equals(default(T1)) && destinationProperty.CanWrite)
                {
                    PropertyInfo propertyInfo = destinationProperty;
                    origin.GetType().GetProperties().Where(
                        x => x.CanRead && (x.Name == propertyInfo.Name && x.PropertyType == propertyInfo.PropertyType))
                          .ToList()
                          .ForEach(x => propertyInfo.SetValue(destination, x.GetValue(origin, null), null));
                }
            }
        }

        private static bool IsGenericIDictionary(PropertyInfo destinationProperty)
        {
            return destinationProperty.PropertyType.IsGenericType && destinationProperty.PropertyType.GetGenericTypeDefinition() == typeof(IDictionary<,>);
        }

        private static bool IsIDictionary(PropertyInfo destinationProperty)
        {
            return typeof(IDictionary).IsAssignableFrom(destinationProperty.PropertyType);
        }

        private static bool IsGenericIList(PropertyInfo destinationProperty)
        {
            return destinationProperty.PropertyType.IsGenericType && destinationProperty.PropertyType.GetGenericTypeDefinition() == typeof(IList<>);
        }

        private static bool IsIList(PropertyInfo destinationProperty)
        {
            return typeof(IList).IsAssignableFrom(destinationProperty.PropertyType);
        }

    }    
}