// Copyright (C) Stichting Deltares 2016. All rights reserved.
//
// This file is part of Ringtoets.
//
// Ringtoets is free software: you can redistribute it and/or modify
// it under the terms of the GNU 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 General Public License for more details.
//
// You should have received a copy of the GNU 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.ComponentModel;
using System.Linq;
using System.Xml;
using System.Xml.Linq;
using Core.Common.Base.IO;
using Ringtoets.Common.IO.Configurations;
using Ringtoets.Common.IO.Properties;
using Ringtoets.Common.IO.Schema;

namespace Ringtoets.Common.IO.Readers
{
    /// <summary>
    /// Extensions methods for <see cref="XElement"/>.
    /// </summary>
    public static class XElementExtensions
    {
        /// <summary>
        /// Gets the <see cref="double"/> value from a descendant element.
        /// </summary>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="descendantElementName">The name of the descendant element.</param>
        /// <returns>The value of the element, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have descendant elements of <paramref name="descendantElementName"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        /// <exception cref="FormatException">Thrown when the value isn't in the correct format.</exception>
        /// <exception cref="OverflowException">Thrown when the value represents a number
        /// less than <see cref="double.MinValue"/> or greater than <see cref="double.MaxValue"/>.</exception>
        public static double? GetDoubleValueFromDescendantElement(this XElement parentElement, string descendantElementName)
        {
            XElement descendantElement = parentElement.GetDescendantElement(descendantElementName);

            return descendantElement != null
                       ? (double?) XmlConvert.ToDouble(descendantElement.Value)
                       : null;
        }

        /// <summary>
        /// Gets the <see cref="int"/> value from a descendant element.
        /// </summary>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="descendantElementName">The name of the descendant element.</param>
        /// <returns>The value of the element, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have descendant elements of <paramref name="descendantElementName"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        /// <exception cref="FormatException">Thrown when the value isn't in the correct format.</exception>
        /// <exception cref="OverflowException">Thrown when the value represents a number
        /// less than <see cref="int.MinValue"/> or greater than <see cref="int.MaxValue"/>.</exception>
        public static int? GetIntegerValueFromDescendantElement(this XElement parentElement, string descendantElementName)
        {
            XElement descendantElement = parentElement.GetDescendantElement(descendantElementName);

            return descendantElement != null
                       ? (int?) XmlConvert.ToInt32(descendantElement.Value)
                       : null;
        }

        /// <summary>
        /// Gets the <see cref="string"/> value from a descendant element.
        /// </summary>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="descendantElementName">The name of the descendant element.</param>
        /// <returns>The value of the element, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have descendant elements of <paramref name="descendantElementName"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        public static string GetStringValueFromDescendantElement(this XElement parentElement, string descendantElementName)
        {
            XElement descendantElement = parentElement.GetDescendantElement(descendantElementName);

            return descendantElement?.Value;
        }

        /// <summary>
        ///  Gets the <see cref="bool"/> value from a descendant element.
        /// </summary>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="descendantElementName">The name of the descendant element.</param>
        /// <returns>The <see cref="bool"/> value, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have descendant elements of <paramref name="descendantElementName"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        /// <exception cref="FormatException">Thrown when the value does not represent a <see cref="bool"/> value.</exception>
        public static bool? GetBoolValueFromDescendantElement(this XElement parentElement, string descendantElementName)
        {
            XElement descendantElement = parentElement.GetDescendantElement(descendantElementName);

            return descendantElement != null
                       ? (bool?) XmlConvert.ToBoolean(descendantElement.Value)
                       : null;
        }

        /// <summary>
        /// Gets the converted value from a descendant element containing a string.
        /// </summary>
        /// <typeparam name="TConverter">The <see cref="TypeConverter"/> to use</typeparam>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="descendantElementName">The name of the descendant element.</param>
        /// <returns>The converted value, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have descendant elements of <paramref name="descendantElementName"/>.</returns>
        /// <exception cref="Exception">Thrown when calling <typeparamref name="TConverter"/>.
        /// <see cref="TypeConverter.ConvertFrom(object)"/> results in an exception being thrown.</exception>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        /// <exception cref="NotSupportedException">Thrown when the conversion cannot be performed.</exception>
        public static object GetConvertedValueFromDescendantStringElement<TConverter>(this XElement parentElement, string descendantElementName)
            where TConverter : TypeConverter, new()
        {
            string stringValue = parentElement.GetStringValueFromDescendantElement(descendantElementName);
            if (stringValue == null)
            {
                return null;
            }
            return new TConverter().ConvertFromInvariantString(stringValue);
        }

        /// <summary>
        /// Gets the converted value from a descendant element containing a double.
        /// </summary>
        /// <typeparam name="TConverter">The <see cref="TypeConverter"/> to use</typeparam>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="descendantElementName">The name of the descendant element.</param>
        /// <returns>The converted value, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have descendant elements of <paramref name="descendantElementName"/>.</returns>
        /// <exception cref="Exception">Thrown when calling <typeparamref name="TConverter"/>.
        /// <see cref="TypeConverter.ConvertFrom(object)"/> results in an exception being thrown.</exception>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        /// <exception cref="FormatException">Thrown when the value from a descendant element is
        /// not in the correct format.</exception>
        /// <exception cref="OverflowException">Thrown when the value from a descendant element 
        /// represents a number less than <see cref="double.MinValue"/> or greater than <see cref="double.MaxValue"/>.</exception>
        /// <exception cref="NotSupportedException">Thrown when the conversion cannot be performed.</exception>
        public static object GetConvertedValueFromDescendantDoubleElement<TConverter>(this XElement parentElement, string descendantElementName)
            where TConverter : TypeConverter, new()
        {
            double? doubleValue = parentElement.GetDoubleValueFromDescendantElement(descendantElementName);
            if (doubleValue == null)
            {
                return null;
            }
            return new TConverter().ConvertFrom(doubleValue);
        }

        /// <summary>
        /// Gets the 'stochast' element from the descendant 'stochasts' element.
        /// </summary>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="stochastName">The name of the stochast element.</param>
        /// <returns>The stochast element, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have stochast elements with the name <paramref name="stochastName"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        public static XElement GetStochastElement(this XElement parentElement, string stochastName)
        {
            if (parentElement == null)
            {
                throw new ArgumentNullException(nameof(parentElement));
            }
            if (stochastName == null)
            {
                throw new ArgumentNullException(nameof(stochastName));
            }

            return parentElement.Elements(ConfigurationSchemaIdentifiers.StochastsElement)
                                .FirstOrDefault()?
                                .Elements(ConfigurationSchemaIdentifiers.StochastElement)
                                .FirstOrDefault(e => e.Attribute(ConfigurationSchemaIdentifiers.NameAttribute)?.Value == stochastName);
        }

        /// <summary>
        /// Gets a descendant element with the given <paramref name="descendantElementName"/>.
        /// </summary>
        /// <param name="parentElement">The <see cref="XElement"/> that contains the descendant element.</param>
        /// <param name="descendantElementName">The name of the descendant element.</param>
        /// <returns>The element, or <c>null</c> when the <paramref name="parentElement"/>
        /// does not have descendant elements of <paramref name="descendantElementName"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        public static XElement GetDescendantElement(this XElement parentElement, string descendantElementName)
        {
            if (parentElement == null)
            {
                throw new ArgumentNullException(nameof(parentElement));
            }
            if (descendantElementName == null)
            {
                throw new ArgumentNullException(nameof(descendantElementName));
            }

            return parentElement.Descendants(descendantElementName).FirstOrDefault();
        }

        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
        /// <exception cref="FormatException">Thrown when the value isn't in the correct format.</exception>
        /// <exception cref="OverflowException">Thrown when the value for mean or standard deviation represents a
        /// number less than <see cref="double.MinValue"/> or greater than <see cref="double.MaxValue"/>.</exception>
        public static StochastConfiguration GetStandardDeviationStochastParameters(this XElement calculationElement, string stochastName)
        {
            if (calculationElement == null)
            {
                throw new ArgumentNullException(nameof(calculationElement));
            }
            if (stochastName == null)
            {
                throw new ArgumentNullException(nameof(stochastName));
            }

            XElement element = calculationElement.GetStochastElement(stochastName);

            if (element != null)
            {
                if (element.Element(ConfigurationSchemaIdentifiers.VariationCoefficientElement) != null)
                {
                    string calculationName = calculationElement.Attribute(ConfigurationSchemaIdentifiers.NameAttribute)?.Value;
                    string message = string.Format(
                        Resources.XElementExtensions_GetStandardDeviationStochastParameters_Stochast_0_defines_VariationCoefficient_instead_of_StandardDeviation_in_Calculation_1_,
                        stochastName,
                        calculationName);
                    throw new CriticalFileReadException(message);
                }

                return new StochastConfiguration
                {
                    Mean = element.GetDoubleValueFromDescendantElement(ConfigurationSchemaIdentifiers.MeanElement),
                    StandardDeviation = element.GetDoubleValueFromDescendantElement(ConfigurationSchemaIdentifiers.StandardDeviationElement)
                };
            }
            return null;
        }

        public static StochastConfiguration GetVariationCoefficientStochastParameters(this XElement calculationElement, string stochastName)
        {
            if (calculationElement == null)
            {
                throw new ArgumentNullException(nameof(calculationElement));
            }
            if (stochastName == null)
            {
                throw new ArgumentNullException(nameof(stochastName));
            }

            XElement element = calculationElement.GetStochastElement(stochastName);

            if (element != null)
            {
                if (element.Element(ConfigurationSchemaIdentifiers.StandardDeviationElement) != null)
                {
                    string calculationName = calculationElement.Attribute(ConfigurationSchemaIdentifiers.NameAttribute)?.Value;
                    string message = string.Format(
                        Resources.XElementExtensions_GetVariationCoefficientStochastParameters_Stochast_0_defines_StandardDeviation_instead_of_VariationCoefficient_in_Calculation_1_,
                        stochastName,
                        calculationName);
                    throw new CriticalFileReadException(message);
                }

                return new StochastConfiguration
                {
                    Mean = element.GetDoubleValueFromDescendantElement(ConfigurationSchemaIdentifiers.MeanElement),
                    VariationCoefficient = element.GetDoubleValueFromDescendantElement(ConfigurationSchemaIdentifiers.VariationCoefficientElement)
                };
            }
            return null;
        }
    }
}