/Trunk/Sources/MvcEngine.Core/Utils/Guard.cs

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text.RegularExpressions;

using System.Globalization;



namespace MvcEngine.Core.Helpers

{

    /// <summary>

    /// This utility class can be used to easily check parameter input and throw exceptions if they do not meet the set

    /// expectations.

    /// </summary>

    public class Guard

    {

        /// <summary>

        /// Private constructor to prevent creating an instance of this class. 

        /// </summary>

        private Guard()

        {

        }



        /// <summary>

        /// Throws an <see cref="ArgumentOutOfRangeException"/> if the given parameter is a negative number.

        /// </summary>

        /// <typeparam name="T">The type of value to check. Should implement <see cref="IComparable{T}"/> interface.</typeparam>

        /// <param name="value">The value to check.</param>

        /// <param name="message">Exception message to give when value is invalid.</param>

        /// <param name="parameterName">Name of the parameter.</param>

        /// <exception cref="ArgumentOutOfRangeException">

        ///     The value is less than zero.

        /// </exception>

        public static void ThrowIfNegative<T>(T value, string message, string parameterName)

            where T : IComparable<T>

        {

            ThrowIfLessThan(value, default(T), message, parameterName);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentOutOfRangeException"/> if the given parameter is a number below the given minimun value.

        /// </summary>

        /// <typeparam name="T">The type of value to check. Should implement <see cref="IComparable{T}"/> interface.</typeparam>

        /// <param name="value">The value to check.</param>

        /// <param name="minValue">The minimum value allowed.</param>

        /// <param name="message">Exception message to give when value is invalid.</param>

        /// <param name="parameterName">Name of the parameter.</param>

        /// <exception cref="ArgumentOutOfRangeException">

        ///     The value is less than zero.

        /// </exception>

        public static void ThrowIfLessThan<T>(T value, T minValue, string message, string parameterName)

            where T : IComparable<T>

        {

            if (value.CompareTo(minValue) < 0)

                throw new ArgumentOutOfRangeException(parameterName, message);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentNullException"/> exception if the passed object equals null.

        /// </summary>

        /// <param name="obj">The object to check.</param>

        /// <exception cref="ArgumentNullException">

        ///     The supplied object <paramref name="obj"/> equals to <see langword="null"/>.

        /// </exception>

        public static void ThrowIfNull(object obj)

        {

            if (obj == null)

                throw new ArgumentNullException(string.Empty);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentNullException"/> exception if the passed object equals null.

        /// </summary>

        /// <param name="obj">>The object to check.</param>

        /// <param name="parameterName">Name of the parameter. Will be displayed with the exception details.</param>

        /// <exception cref="ArgumentNullException">

        ///     The supplied object <paramref name="obj"/> equals to <see langword="null"/>.

        /// </exception>

        public static void ThrowIfNull(object obj, string parameterName)

        {

            if (obj == null)

                throw new ArgumentNullException(parameterName);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentNullException"/> exception if the passed object equals null.

        /// </summary>

        /// <param name="obj">>The object to check.</param>

        /// <param name="parameterName">Name of the parameter. Will be displayed with the exception details.</param>

        /// <param name="message">Exception message to give when value is invalid.</param>

        /// <exception cref="ArgumentNullException">

        ///     The supplied object <paramref name="obj"/> equals to <see langword="null"/>.

        /// </exception>

        public static void ThrowIfNull(object obj, string parameterName, string message)

        {

            if (obj == null)

                throw new ArgumentNullException(parameterName, message);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentException"/> if the passed string is an emtpy string.

        /// </summary>

        /// <param name="str">The string to check.</param>

        /// <exception cref="ArgumentException">

        ///     The <paramref name="str"/> is <see langword="null"/> or empty.

        /// </exception>

        public static void ThrowIfEmptyString(string str)

        {

            if (string.IsNullOrEmpty(str))

                throw new ArgumentException(string.Empty);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentException"/> if the passed string is an emtpy string.

        /// </summary>

        /// <param name="str">The string to check.</param>

        /// <param name="message">Exception message to give when value is invalid.</param>

        /// <exception cref="ArgumentException">

        ///     The <paramref name="str"/> is <see langword="null"/> or empty.

        /// </exception>

        public static void ThrowIfEmptyString(string str, string message)

        {

            if (string.IsNullOrEmpty(str))

                throw new ArgumentException(message);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentException"/> if the passed GUID is emtpy.

        /// </summary>

        /// <param name="guid">The GUID to check.</param>

        /// <param name="message">Exception message to give when value is invalid.</param>

        /// <exception cref="ArgumentException">

        /// The <paramref name="guid"/> is <see langword="null"/> or empty.

        /// </exception>

        public static void ThrowIfEmptyGuid(Guid guid, string message)

        {

            if (guid == Guid.Empty)

                throw new ArgumentException(message);

        }



        public static void ThrowIfEmptyGuid(Guid guid)

        {

            if (guid == Guid.Empty)

                throw new ArgumentException("Argument can't be an empty Guid.");

        }



        /// <summary>

        /// Throws an <see cref="ArgumentException"/> if two values are not equal.

        /// </summary>

        /// <typeparam name="T"></typeparam>

        /// <param name="value1">The first value to compare.</param>

        /// <param name="value2">The second value to compare.</param>

        /// <param name="message">Exception message to give when values are not equal.</param>

        /// <exception cref="ArgumentException">

        /// Values are not equal.

        /// </exception>

        public static void ThrowIfNotEqual<T>(T value1, T value2, string message)

        {

            if (!EqualityComparer<T>.Default.Equals(value1, value2))

                throw new ArgumentException(message);

        }



        /// <summary>

        ///  Throws an <see cref="ArgumentException"/> if the passed string is an emtpy string.

        /// </summary>

        /// <param name="str">The string to check.</param>

        /// <param name="message">Exception message to give when value is invalid.</param>

        /// <param name="parameterName">Name of the parameter. Will be displayed with the exception details.</param>

        /// <exception cref="ArgumentException">

        ///     The <paramref name="str"/> is <see langword="null"/> or empty.

        /// </exception>

        public static void ThrowIfEmptyString(string str, string message, string parameterName)

        {

            if (string.IsNullOrEmpty(str))

                throw new ArgumentException(message, parameterName);

        }



        /// <summary>

        /// Thows an <see cref="ArgumentNullException"/> if the passed collection is emtpy or a <see cref="ArgumentException"/>

        /// if the collection does not contain any elements.

        /// </summary>

        /// <typeparam name="T">Types of objects.</typeparam>

        /// <param name="collection">Collection to check.</param>

        /// <param name="parameterName">Name of the parameter. Will be displayed with the exception details.</param>

        /// <param name="message">Exception message to give when value is invalid.</param>

        /// <exception cref="ArgumentNullException">

        ///     The supplied collection is <see langword="null"/>.

        /// </exception>

        /// <exception cref="ArgumentException">

        ///     The supplied collection has no items.

        /// </exception>

        public static void ThrowIfEmpty<T>(IEnumerable<T> collection, string parameterName, string message)

        {

            if (collection == null)

                throw new ArgumentNullException(parameterName, message);



            if (!collection.Any())

                throw new ArgumentException(message, parameterName);

        }



        /// <summary>

        /// Throws an <see cref="ArgumentException"/> if the supplied string has a length longer than the specified length.

        /// </summary>

        /// <param name="str">String to check.</param>

        /// <param name="maxLength">The maximum string length allowed.</param>

        /// <param name="parameterName">Name of the parameter. Will be displayed with the exception details.</param>

        /// <exception cref="ArgumentOutOfRangeException">

        ///     The supplied string is longer than the given <paramref name="maxLength"/>.

        /// </exception>

        public static void ThrowIfLonger(string str, int maxLength, string parameterName)

        {

            if (str.Length > maxLength)

                throw new ArgumentOutOfRangeException(parameterName, String.Format(CultureInfo.CurrentCulture, "{0} cannot be longer than {1} characters.", parameterName, maxLength));

        }



        /// <summary>

        /// Throws an <see cref="ArgumentException"/> if input string does not match regex pattern.

        /// </summary>

        /// <param name="str">The input string.</param>

        /// <param name="regexPattern">The regex pattern.</param>

        /// <param name="parameterName">Name of the parameter being validated.</param>

        /// <exception cref="ArgumentException">

        ///     The <paramref name="str"/> does not match the <paramref name="regexPattern"/>.

        /// </exception>

        public static void ThrowIfDoNotMatch(string str, string regexPattern, string parameterName)

        {

            if (!Regex.IsMatch(str, regexPattern))

                throw new ArgumentException(string.Format(CultureInfo.CurrentCulture, "String '{0}' does not match the regex pattern '{1}'.", str, regexPattern), parameterName);

        }

    }



}