using System;
using UnitTestSharp;
using static Glass.UnitTests.MessageBoxTests;

namespace Glass.UnitTests
{
    public class MessageBoxMaterialTests : TestFixture
    {
        public class BitIndexOfTests : TestFixture
        {
            public void ASingleBit_IsItsPositionCountingFromTheLowest()
            {
                CheckEqual(0, MessageBoxMaterial.BitIndexOf(TestAnswer.Yes));
                CheckEqual(1, MessageBoxMaterial.BitIndexOf(TestAnswer.No));
                CheckEqual(2, MessageBoxMaterial.BitIndexOf(TestAnswer.Cancel));
            }

            public void TheTopBitOfAWideEnum_Is63()
            {
                CheckEqual(63, MessageBoxMaterial.BitIndexOf(WideAnswer.High));
            }

            public void TheSignBitOfASignedEnum_IsItsPositionInTheEnumsWidth()
            {
                CheckEqual(7, MessageBoxMaterial.BitIndexOf(SignedAnswer.Sign));
            }

            public void NoBits_Throws()
            {
                CheckThrow(typeof(ArgumentException));
                MessageBoxMaterial.BitIndexOf((TestAnswer)0);
            }

            public void SeveralBits_Throws()
            {
                CheckThrow(typeof(ArgumentException));
                MessageBoxMaterial.BitIndexOf(TestAnswer.Yes | TestAnswer.No);
            }
        }

        public class BitsOfTests : TestFixture
        {
            public void Always_IsTheBitsTheValueSets()
            {
                CheckEqual(5UL, MessageBoxMaterial.BitsOf(TestAnswer.Yes | TestAnswer.Cancel));
            }

            public void AnEnumWithNoBitsSet_IsZero()
            {
                CheckEqual(0UL, MessageBoxMaterial.BitsOf((TestAnswer)0));
            }

            public void AWideEnum_KeepsItsTopBit()
            {
                CheckEqual(1UL << 63, MessageBoxMaterial.BitsOf(WideAnswer.High));
            }

            public void ANegativeSignedEnum_StaysWithinItsOwnWidth()
            {
                CheckEqual(0x80UL, MessageBoxMaterial.BitsOf(SignedAnswer.Sign));
                CheckEqual(0x81UL, MessageBoxMaterial.BitsOf(SignedAnswer.Sign | SignedAnswer.Low));
            }
        }

        public class WithButtonTests : TestFixture
        {
            public void Always_GivesTheAnswersBitTheLook()
            {
                ButtonMaterial look = DropdownTests.Arrow(1, 1);

                MessageBoxMaterial material = new MessageBoxMaterial().WithButton(TestAnswer.No, look);

                CheckEqual(2, material.Buttons.Length);
                CheckEqual(look, material.Buttons[1]);
                CheckEqual(default(ButtonMaterial), material.Buttons[0]);
            }

            public void ALaterOne_KeepsTheEarlierLooksAndGrowsTheArray()
            {
                ButtonMaterial yes = DropdownTests.Arrow(1, 1);
                ButtonMaterial cancel = DropdownTests.Arrow(3, 3);

                MessageBoxMaterial material = new MessageBoxMaterial()
                    .WithButton(TestAnswer.Yes, yes)
                    .WithButton(TestAnswer.Cancel, cancel);

                CheckEqual(3, material.Buttons.Length);
                CheckEqual(yes, material.Buttons[0]);
                CheckEqual(cancel, material.Buttons[2]);
            }

            public void ForABitAlreadySet_ReplacesItsLookAndKeepsTheLength()
            {
                ButtonMaterial replacement = DropdownTests.Arrow(5, 5);
                MessageBoxMaterial material = new MessageBoxMaterial()
                    .WithButton(TestAnswer.No, DropdownTests.Arrow(1, 1))
                    .WithButton(TestAnswer.Cancel, DropdownTests.Arrow(3, 3));

                material = material.WithButton(TestAnswer.No, replacement);

                CheckEqual(3, material.Buttons.Length);
                CheckEqual(replacement, material.Buttons[1]);
            }

            public void Always_LeavesTheOriginalAlone()
            {
                MessageBoxMaterial original = Measurements;
                ButtonMaterial[] looks = original.Buttons;
                ButtonMaterial first = looks[0];

                original.WithButton(TestAnswer.Yes, DropdownTests.Arrow(9, 9));

                CheckTrue(ReferenceEquals(looks, original.Buttons));
                CheckEqual(first, original.Buttons[0]);
            }

            public void Always_KeepsTheOtherFields()
            {
                MessageBoxMaterial material = Measurements with { Spacing = 7 };

                MessageBoxMaterial changed = material.WithButton(TestAnswer.Yes, DropdownTests.Arrow(9, 9));

                CheckEqual(7, changed.Spacing);
                CheckTrue(ReferenceEquals(material.TextStyle, changed.TextStyle));
            }

            public void ForSeveralBits_Throws()
            {
                CheckThrow(typeof(ArgumentException));
                new MessageBoxMaterial().WithButton(TestAnswer.Yes | TestAnswer.No, DropdownTests.Arrow(1, 1));
            }
        }
    }
}