using System;
using UnitTestSharp;

namespace Amphora.UnitTests
{
    public class FailureKindTests : TestFixture
    {
        public class CtorTests : TestFixture
        {
            public void KeepsTheName()
            {
                var kind = new MessageFailureKind("Amphora.UnitTests.Named", "message");

                CheckEqual("Amphora.UnitTests.Named", kind.Name);
            }

            public void IdIsTheNamesId()
            {
                var kind = new MessageFailureKind("Amphora.UnitTests.Named", "message");

                CheckEqual(FailureKind.IdOf("Amphora.UnitTests.Named"), kind.Id);
            }

            public void NullName_Throws()
            {
                CheckThrow(typeof(ArgumentNullException));
                new MessageFailureKind(name: null, message: "message");
            }
        }

        public class IdOfTests : TestFixture
        {
            public void Empty_IsTheOffsetBasis()
            {
                CheckEqual(0xcbf29ce484222325UL, FailureKind.IdOf(""));
            }

            public void Ascii_HashesBothBytesOfEachCharacter()
            {
                CheckEqual(0x089be207b544f1e4UL, FailureKind.IdOf("a"));
            }

            public void NamespacedName_MatchesItsGoldenValue()
            {
                CheckEqual(0x9727bcbc5d7e3cb7UL, FailureKind.IdOf("Glass.FileSystem.NotFound"));
            }

            public void NonAscii_HashesTheLowByteFirst()
            {
                CheckEqual(0x07d03807b4981da2UL, FailureKind.IdOf(((char)0x4E2D).ToString()));
            }

            public void View_HashesOnlyItsOwnCharacters()
            {
                CheckEqual(FailureKind.IdOf("a"), FailureKind.IdOf(new StringView("bac", 1, 2)));
            }

            public void AllocatesNothing()
            {
                CheckEqual(0L, Allocations.During(
                    () => Allocations.IdSink = FailureKind.IdOf("Glass.FileSystem.NotFound")));
            }
        }

        public class CanSerializeReferenceTests : TestFixture
        {
            public void Null_IsTrue()
            {
                CheckTrue(FailureTestKinds.Unreachable.CanSerializeReference(null));
            }

            public void String_IsTrue()
            {
                CheckTrue(FailureTestKinds.Unreachable.CanSerializeReference("ref"));
            }

            public void OtherObject_IsFalse()
            {
                CheckFalse(FailureTestKinds.Unreachable.CanSerializeReference(new object()));
            }
        }
    }
}