using System;
using Annulus;
using Azimuth;
using UnitTestSharp;
using static Glass.UnitTests.TextBoxTests;

namespace Glass.UnitTests
{
    public class TextBoxCompositionTargetTests : TestFixture
    {
        public static readonly TextBoxMaterial TargetMaterial = CompositionMaterial with
        {
            CompositionTarget = new SolidColorMaterial(),
            CompositionTargetThickness = 4,
        };

        public static bool ShowsTarget(TextBox box) => BandCount(box.Content.CompositionTarget) > 0;

        public static TextBox BoxComposing(int caret, int targetStart, int targetEnd)
        {
            TextBox box = NewBox("ad", material: TargetMaterial);
            box.Buffer.MoveTo(1, extend: false);
            box.CompositionUpdate("bcde", caret, targetStart, targetEnd);
            return box;
        }

        public class CompositionUpdateTests : TestFixture
        {
            public void ShowsTheClauseBeingConverted()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                Check(ShowsTarget(box));
                CheckEqual(1, box.CompositionTargetStart);
                CheckEqual(3, box.CompositionTargetEnd);
            }

            public void DrawsItAsAThickerLineUnderJustThatClause()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                CheckEqual(Rect.FromPositionAndSize(new Vector(20, 6), new Vector(20, 4)),
                    box.Content.CompositionTarget[0]);
            }

            public void TheWholeCompositionKeepsItsOwnThinnerLine()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                CheckEqual(Rect.FromPositionAndSize(new Vector(10, 8), new Vector(40, 2)), box.Content.Composition[0]);
            }

            public void ATargetAtTheStart_StartsWhereTheCompositionDoes()
            {
                TextBox box = BoxComposing(caret: 2, targetStart: 0, targetEnd: 2);

                CheckEqual(Rect.FromPositionAndSize(new Vector(10, 6), new Vector(20, 4)),
                    box.Content.CompositionTarget[0]);
            }

            public void ATargetAtTheEnd_EndsWhereTheCompositionDoes()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 2, targetEnd: 4);

                CheckEqual(Rect.FromPositionAndSize(new Vector(30, 6), new Vector(20, 4)),
                    box.Content.CompositionTarget[0]);
            }

            public void NoTarget_HidesIt()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 0, targetEnd: 0);

                CheckFalse(ShowsTarget(box));
            }

            public void AnEmptyTargetInTheMiddle_HidesIt()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 2, targetEnd: 2);

                CheckFalse(ShowsTarget(box));
            }

            public void TheTwoArgumentFormOnControl_MarksNoClause()
            {
                TextBox box = NewBox("ad", material: TargetMaterial);
                box.Buffer.MoveTo(1, extend: false);

                box.CompositionUpdate("bc", 2);

                CheckEqual(0, box.CompositionTargetStart);
                CheckEqual(0, box.CompositionTargetEnd);
                CheckFalse(ShowsTarget(box));
            }

            public void ANewUpdateWithoutOne_TakesTheClauseDown()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                box.CompositionUpdate("bcde", 4, 0, 0);

                CheckFalse(ShowsTarget(box));
                CheckEqual(0, box.CompositionTargetStart);
                CheckEqual(0, box.CompositionTargetEnd);
            }

            public void ANewClause_MovesTheLine()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                box.CompositionUpdate("bcde", 4, 2, 4);

                CheckEqual(Rect.FromPositionAndSize(new Vector(30, 6), new Vector(20, 4)),
                    box.Content.CompositionTarget[0]);
            }

            public void ANegativeStart_Throws()
            {
                TextBox box = NewBox();

                CheckThrow(typeof(ArgumentOutOfRangeException));
                box.CompositionUpdate("ab", 1, -1, 1);
            }

            public void AnEndBeforeTheStart_Throws()
            {
                TextBox box = NewBox();

                CheckThrow(typeof(ArgumentOutOfRangeException));
                box.CompositionUpdate("abc", 1, 2, 1);
            }

            public void AnEndPastTheText_Throws()
            {
                TextBox box = NewBox();

                CheckThrow(typeof(ArgumentOutOfRangeException));
                box.CompositionUpdate("ab", 1, 0, 3);
            }

            public void AClauseCoveringTheWholeText_IsAllowed()
            {
                TextBox box = NewBox();

                box.CompositionUpdate("ab", 1, 0, 2);

                CheckEqual(2, box.CompositionTargetEnd);
            }

            public void WhileDisabled_IsIgnored()
            {
                TextBox box = NewBox("ad", material: TargetMaterial);
                box.Enabled = false;

                box.CompositionUpdate("bc", 2, 0, 2);

                CheckEqual(0, box.CompositionTargetEnd);
                CheckFalse(ShowsTarget(box));
            }
        }

        public class CompositionEndTests : TestFixture
        {
            public void TakesTheClauseDown()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                box.CompositionEnd();

                CheckFalse(ShowsTarget(box));
                CheckEqual(0, box.CompositionTargetStart);
                CheckEqual(0, box.CompositionTargetEnd);
            }
        }

        public class TextInputTests : TestFixture
        {
            public void ACommit_TakesTheClauseDown()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                box.TextInput("x", new KeyboardManager());

                CheckFalse(ShowsTarget(box));
                CheckEqual(0, box.CompositionTargetEnd);
            }
        }

        public class DroppingTheCompositionTests : TestFixture
        {
            public void BeingDisabled_TakesTheClauseDown()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);

                box.Enabled = false;

                CheckFalse(ShowsTarget(box));
                CheckEqual(0, box.CompositionTargetEnd);
            }

            public void LosingFocus_TakesTheClauseDown()
            {
                TextBox box = BoxComposing(caret: 4, targetStart: 1, targetEnd: 3);
                var keys = Focus(box);
                keys.ClearFocus();

                CheckFalse(ShowsTarget(box));
            }
        }

        public class TextBoxMaterialTests : TestFixture
        {
            public void RoundTripsTheClauseLook()
            {
                var box = NewBox();
                var look = new SolidColorMaterial();

                box.TextBoxMaterial = new TextBoxMaterial
                {
                    Scale = default,
                    Background = default,
                    Text = default,
                    Selection = default,
                    InactiveSelection = default,
                    Caret = default,
                    CaretWidth = default,
                    Composition = default,
                    CompositionThickness = default,
                    ScrollBar = default,
                    HorizontalScrollBar = default,
                    CompositionTarget = look,
                    CompositionTargetThickness = 5,
                };

                TextBoxMaterial back = box.TextBoxMaterial;
                Check(ReferenceEquals(look, back.CompositionTarget));
                CheckEqual((Scalar)5, back.CompositionTargetThickness);
            }
        }
    }
}