using System;

using System.Collections.Generic;

using System.Linq;

using NUnit.Framework;

using NUnit.Framework.Internal;

using static ShuffleCharacters.StringExtension;

​

#pragma warning disable CA1707

​

namespace ShuffleCharacters.Tests

{

    [TestFixture]

    public class StringExtensionTests

    {

        private static IEnumerable<TestCaseData> TestCases

        {

            get

            {

                yield return new TestCaseData("Привет Эпам", 2, "Пепртаи мвЭ");

                yield return new TestCaseData("Hello EPAM!", 2, "HoAe MlE!lP");

                yield return new TestCaseData("Hello EPAM!", 22, "HoAe MlE!lP");

                yield return new TestCaseData("Hello EPAM!", 21, "HloEA!el PM");

            }

        }

​

        [TestCase("A", 1, ExpectedResult = "A")]

        [TestCase("A", 2, ExpectedResult = "A")]

        [TestCase("AB", 1, ExpectedResult = "AB")]

        [TestCase("AB", 2, ExpectedResult = "AB")]

        [TestCase("AB", 3, ExpectedResult = "AB")]

        [TestCase("123456789", 1, ExpectedResult = "135792468")]

        [TestCase("123456789", 2, ExpectedResult = "159483726")]

        [TestCase("123456789", 3, ExpectedResult = "198765432")]

        [TestCase("123456789", 4, ExpectedResult = "186429753")]

        [TestCase("123456789", 5, ExpectedResult = "162738495")]

        [TestCase("123456789", 6, ExpectedResult = "123456789")]

        [TestCase("123456789", 7, ExpectedResult = "135792468")]

        [TestCase("Das lässt sich nicht ändern.", 10, ExpectedResult = "Drdätcnhi sä anen hi cstsls.")]

        [TestCase("Das lässt sich nicht ändern.", 5, ExpectedResult = "Däsn r thhdasiiänl  tessccn.")]

        [TestCase("1234567890", int.MaxValue, ExpectedResult = "1357924680")]

        [TestCase("Lorem ipsum dolor sit amet consectetur adipisicing elit." +

                  " Excepturi laudantium, vel natus fugiat, illum dignissimos" +

                  " fuga officia maiores ea at ex quis animi incidunt doloremque, " +

                  "dolor quia. Quisquam, veniam hic!", int.MaxValue,

            ExpectedResult = "Ldeodeeamniat e oiaeumsac mtuf a  nua Eiadsn mocav " +

                             "ivsdiau pm rdlirqeinitaei iutigqir  e pis li  ac nus " +

                             "Qteuto egomrp fnittsmqeri uo., ,icuaohr,gn,oass iclalm " +

                             "uieoilfuncnoismudxqlttse itid umuimclii.sxl ougfar!")]

        [TestCase(@"!#%')+-/13579;=?ACEGIKMOQSU""$&(*,.02468:<>@BDFHJLNPRT", 5,

            ExpectedResult = @"!,7BM#.9DO%0;FQ'2=HS)4?JU+6AL""-8CN$/:EP&1<GR(3>IT*5@K")]

        [TestCase(@"!#%')+-/13579;=?ACEGIKMOQSU""$&(*,.02468:<>@BDFHJLNPRT", 20,

            ExpectedResult = @"!QLGB=83.)$TOJE@;61,'""RMHC>94/*%UPKFA<72-(#SNID?:50+&")]

        [TestCase(@"!#%')+-/13579;=?ACEGIKMOQSU""$&(*,.02468:<>@BDFHJLNPRT", 955031,

            ExpectedResult = @"!""#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTU")]

        [TestCase(@"!snid_ZUPKFA<72-(#upkfa\WRMHC>94/*%wrmhc^YTOJE@;61,'""toje`[VQLGB=83.)$vqlgb]XSNID?:50+&x",

            2147483637,

            ExpectedResult =

                  @"!/=KYgu,:HVdr)7ESao&4BP^l#1?M[iw.<JXft+9GUcq(6DR`n%3AO]k""0>LZhv-;IWes*8FTbp'5CQ_m$2@N\jx")]

        public string ShuffleCharsTests(string source, int count)

            => ShuffleChars(source, count);

​

        [Test]

        public void ShuffleChars_IfSourceStringIsNull_ThrowArgumentException()

            => Assert.Throws<ArgumentException>(

                () => ShuffleChars(null, int.MaxValue));

​

        [Test]

        public void ShuffleChars_IfSourceStringIsEmpty_ThrowArgumentException()

            => Assert.Throws<ArgumentException>(

                () => ShuffleChars(string.Empty, int.MaxValue));

​

        [Test]

        public void ShuffleChars_IfSourceStringIsWhiteSpaced_ThrowArgumentException()

            => Assert.Throws<ArgumentException>(

                () => ShuffleChars("   ", int.MaxValue));

​

        [Test]

        public void ShuffleChars_IfSourceStringIsWhiteSpacedWithInvisibleChars_ThrowArgumentException()

            => Assert.Throws<ArgumentException>(

                () => ShuffleChars("  \t\n  \t \r", int.MaxValue));

​

        [Test]

        public void ShuffleChars_NegativeCounter_ThrowArgumentException()

            => Assert.Throws<ArgumentException>(

                () => ShuffleChars("Das lässt sich nicht ändern.", -1));

​

        [TestCaseSource(nameof(TestCases))]

        public void ShuffleChars_WithTestCaseData(string source, int count, string expected)

        {

            Assert.AreEqual(expected, ShuffleChars(source, count));

        }

    }

}

​