osu/osu.Game/Graphics/UserInterface/OsuTextBox.cs

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.

using osu.Framework.Allocation;
using osu.Framework.Audio.Track;
using osu.Framework.Graphics;
using osu.Framework.Graphics.Sprites;
using osu.Framework.Graphics.UserInterface;
using osu.Game.Graphics.Sprites;
using osuTK.Graphics;
using osu.Framework.Extensions.Color4Extensions;
using osu.Framework.Input.Events;
using osu.Game.Beatmaps.ControlPoints;
using osu.Game.Graphics.Containers;
using osuTK;

namespace osu.Game.Graphics.UserInterface
{
    public class OsuTextBox : BasicTextBox
    {
        protected override float LeftRightPadding => 10;

        protected override float CaretWidth => 3;

        protected override SpriteText CreatePlaceholder() => new OsuSpriteText
        {
            Font = OsuFont.GetFont(italics: true),
            Colour = new Color4(180, 180, 180, 255),
            Margin = new MarginPadding { Left = 2 },
        };

        public OsuTextBox()
        {
            Height = 40;
            TextContainer.Height = 0.5f;
            CornerRadius = 5;
            LengthLimit = 1000;

            Current.DisabledChanged += disabled => { Alpha = disabled ? 0.3f : 1; };
        }

        [BackgroundDependencyLoader]
        private void load(OsuColour colour)
        {
            BackgroundUnfocused = Color4.Black.Opacity(0.5f);
            BackgroundFocused = OsuColour.Gray(0.3f).Opacity(0.8f);
            BackgroundCommit = BorderColour = colour.Yellow;
        }

        protected override Color4 SelectionColour => new Color4(249, 90, 255, 255);

        protected override void OnFocus(FocusEvent e)
        {
            BorderThickness = 3;
            base.OnFocus(e);
        }

        protected override void OnFocusLost(FocusLostEvent e)
        {
            BorderThickness = 0;

            base.OnFocusLost(e);
        }

        protected override Drawable GetDrawableCharacter(char c) => new OsuSpriteText { Text = c.ToString(), Font = OsuFont.GetFont(size: CalculatedTextSize) };

        protected override Caret CreateCaret() => new BeatCaret
        {
            CaretWidth = CaretWidth,
            SelectionColour = SelectionColour,
        };

        private class BeatCaret : BasicCaret
        {
            private bool hasSelection;

            public BeatCaret()
            {
                AddInternal(new CaretBeatSyncedContainer(this));
            }

            public override void DisplayAt(Vector2 position, float? selectionWidth)
            {
                base.DisplayAt(position, selectionWidth);

                hasSelection = selectionWidth != null;
                if (selectionWidth == null)
                    ClearTransforms(targetMember: nameof(Alpha));
            }

            private class CaretBeatSyncedContainer : BeatSyncedContainer
            {
                private readonly BeatCaret caret;

                public CaretBeatSyncedContainer(BeatCaret caret)
                {
                    this.caret = caret;
                    MinimumBeatLength = 300;
                }

                protected override void OnNewBeat(int beatIndex, TimingControlPoint timingPoint, EffectControlPoint effectPoint, TrackAmplitudes amplitudes)
                {
                    if (!caret.hasSelection)
                        caret.FadeTo(0.7f).FadeTo(0.4f, timingPoint.BeatLength, Easing.InOutSine);
                }
            }
        }
    }
}