ManiaPlayfield.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.

#nullable disable

using osu.Framework.Graphics;
using osu.Framework.Graphics.Containers;
using System;
using System.Collections.Generic;
using System.Linq;
using JetBrains.Annotations;
using osu.Framework.Allocation;
using osu.Framework.Graphics.Primitives;
using osu.Game.Rulesets.Mania.Beatmaps;
using osu.Game.Rulesets.Mania.Objects;
using osu.Game.Rulesets.Objects;
using osu.Game.Rulesets.Objects.Drawables;
using osu.Game.Rulesets.UI.Scrolling;
using osuTK;

namespace osu.Game.Rulesets.Mania.UI
{
    [Cached]
    public partial class ManiaPlayfield : ScrollingPlayfield
    {
        public IReadOnlyList<Stage> Stages => stages;

        private readonly List<Stage> stages = new List<Stage>();

        public override Quad SkinnableComponentScreenSpaceDrawQuad
        {
            get
            {
                RectangleF totalArea = RectangleF.Empty;

                for (int i = 0; i < Stages.Count; ++i)
                {
                    var stageArea = Stages[i].ScreenSpaceDrawQuad.AABBFloat;
                    totalArea = i == 0 ? stageArea : RectangleF.Union(totalArea, stageArea);
                }

                return totalArea;
            }
        }

        public override bool ReceivePositionalInputAt(Vector2 screenSpacePos)
        {
            foreach (var s in stages)
            {
                if (s.ReceivePositionalInputAt(screenSpacePos))
                    return true;
            }

            return false;
        }

        public ManiaPlayfield(List<StageDefinition> stageDefinitions)
        {
            ArgumentNullException.ThrowIfNull(stageDefinitions);

            if (stageDefinitions.Count <= 0)
                throw new ArgumentException("Can't have zero or fewer stages.");

            GridContainer playfieldGrid;
            AddInternal(playfieldGrid = new GridContainer
            {
                RelativeSizeAxes = Axes.Both,
                Content = new[] { new Drawable[stageDefinitions.Count] }
            });

            var columnAction = ManiaAction.Key1;
            int firstColumnIndex = 0;

            for (int i = 0; i < stageDefinitions.Count; i++)
            {
                var newStage = CreateStage(firstColumnIndex, stageDefinitions[i], ref columnAction);

                playfieldGrid.Content[0][i] = newStage;

                stages.Add(newStage);
                AddNested(newStage);

                firstColumnIndex += newStage.Columns.Length;
            }
        }

        [Pure]
        protected virtual Stage CreateStage(int firstColumnIndex, StageDefinition stageDefinition, ref ManiaAction columnAction) => new Stage(firstColumnIndex, stageDefinition, ref columnAction);

        public override void Add(HitObject hitObject) => getStageByColumn(((ManiaHitObject)hitObject).Column).Add(hitObject);

        public override bool Remove(HitObject hitObject) => getStageByColumn(((ManiaHitObject)hitObject).Column).Remove(hitObject);

        public override void Add(DrawableHitObject h) => getStageByColumn(((ManiaHitObject)h.HitObject).Column).Add(h);

        public override bool Remove(DrawableHitObject h) => getStageByColumn(((ManiaHitObject)h.HitObject).Column).Remove(h);

        public void Add(BarLine barLine) => stages.ForEach(s => s.Add(barLine));

        /// <summary>
        /// Find the closest column to the proposed screen space position.
        /// </summary>
        /// <param name="screenSpaceX">The screen-space X coordinate.</param>
        /// <returns>The column which the <paramref name="screenSpaceX"/> is closest to.</returns>
        public Column GetClosestColumnByPosition(float screenSpaceX)
        {
            return stages
                   .SelectMany(s => s.Columns.Select((Column column, float distance) (c) => (c, Math.Abs(screenSpaceX - c.ScreenSpaceDrawQuad.Centre.X))))
                   .MinBy(c => c.distance).column;
        }

        /// <summary>
        /// Retrieves a <see cref="Column"/> by index.
        /// </summary>
        /// <param name="index">The index of the column.</param>
        /// <returns>The <see cref="Column"/> corresponding to the given index.</returns>
        /// <exception cref="ArgumentOutOfRangeException">If <paramref name="index"/> is less than 0 or greater than <see cref="TotalColumns"/>.</exception>
        public Column GetColumn(int index)
        {
            if (index < 0 || index > TotalColumns - 1)
                throw new ArgumentOutOfRangeException(nameof(index));

            foreach (var stage in stages)
            {
                if (index >= stage.Columns.Length)
                {
                    index -= stage.Columns.Length;
                    continue;
                }

                return stage.Columns[index];
            }

            throw new ArgumentOutOfRangeException(nameof(index));
        }

        /// <summary>
        /// Retrieves the total amount of columns across all stages in this playfield.
        /// </summary>
        public int TotalColumns
        {
            get
            {
                int sum = 0;

                foreach (var stage in stages)
                    sum += stage.Columns.Length;

                return sum;
            }
        }

        private Stage getStageByColumn(int column)
        {
            int sum = 0;

            foreach (var stage in stages)
            {
                sum += stage.Columns.Length;
                if (sum > column)
                    return stage;
            }

            return null;
        }
    }
}