// 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.Allocation;
using osu.Framework.Bindables;
using osu.Framework.Graphics;
using osu.Framework.Graphics.Containers;
using osu.Framework.Graphics.Pooling;
using osu.Framework.Input.Bindings;
using osu.Framework.Input.Events;
using osu.Framework.Platform;
using osu.Game.Extensions;
using osu.Game.Rulesets.Judgements;
using osu.Game.Rulesets.Mania.Objects;
using osu.Game.Rulesets.Mania.Objects.Drawables;
using osu.Game.Rulesets.Mania.Skinning;
using osu.Game.Rulesets.Mania.UI.Components;
using osu.Game.Rulesets.Objects.Drawables;
using osu.Game.Rulesets.UI;
using osu.Game.Rulesets.UI.Scrolling;
using osu.Game.Skinning;
using osuTK;
using osuTK.Graphics;

namespace osu.Game.Rulesets.Mania.UI
{
    [Cached]
    public partial class Column : ScrollingPlayfield, IKeyBindingHandler<ManiaAction>
    {
        public const float COLUMN_WIDTH = 80;
        public const float SPECIAL_COLUMN_WIDTH = 70;

        /// <summary>
        /// The index of this column as part of the whole playfield.
        /// </summary>
        public readonly int Index;

        public readonly Bindable<ManiaAction> Action = new Bindable<ManiaAction>();

        public readonly ColumnHitObjectArea HitObjectArea;

        internal readonly Container BackgroundContainer = new Container { RelativeSizeAxes = Axes.Both };

        internal readonly Container TopLevelContainer = new Container { RelativeSizeAxes = Axes.Both };

        private DrawablePool<PoolableHitExplosion> hitExplosionPool;
        private readonly OrderedHitPolicy hitPolicy;
        public Container UnderlayElements => HitObjectArea.UnderlayElements;

        private GameplaySampleTriggerSource sampleTriggerSource;

        /// <summary>
        /// Whether this is a special (ie. scratch) column.
        /// </summary>
        public readonly bool IsSpecial;

        public readonly Bindable<Color4> AccentColour = new Bindable<Color4>(Color4.Black);

        public Column(int index, bool isSpecial)
        {
            Index = index;
            IsSpecial = isSpecial;

            RelativeSizeAxes = Axes.Y;
            Width = COLUMN_WIDTH;

            hitPolicy = new OrderedHitPolicy(HitObjectContainer);
            HitObjectArea = new ColumnHitObjectArea(HitObjectContainer) { RelativeSizeAxes = Axes.Both };
        }

        [Resolved]
        private ISkinSource skin { get; set; }

        [BackgroundDependencyLoader]
        private void load(GameHost host)
        {
            SkinnableDrawable keyArea;

            skin.SourceChanged += onSourceChanged;
            onSourceChanged();

            InternalChildren = new Drawable[]
            {
                hitExplosionPool = new DrawablePool<PoolableHitExplosion>(5),
                sampleTriggerSource = new GameplaySampleTriggerSource(HitObjectContainer),
                HitObjectArea,
                keyArea = new SkinnableDrawable(new ManiaSkinComponentLookup(ManiaSkinComponents.KeyArea), _ => new DefaultKeyArea())
                {
                    RelativeSizeAxes = Axes.Both,
                },
                // For input purposes, the background is added at the highest depth, but is then proxied back below all other elements externally
                // (see `Stage.columnBackgrounds`).
                BackgroundContainer,
                TopLevelContainer,
                new ColumnTouchInputArea(this)
            };

            var background = new SkinnableDrawable(new ManiaSkinComponentLookup(ManiaSkinComponents.ColumnBackground), _ => new DefaultColumnBackground())
            {
                RelativeSizeAxes = Axes.Both,
            };

            background.ApplyGameWideClock(host);
            keyArea.ApplyGameWideClock(host);

            BackgroundContainer.Add(background);
            TopLevelContainer.Add(HitObjectArea.Explosions.CreateProxy());

            RegisterPool<Note, DrawableNote>(10, 50);
            RegisterPool<HoldNote, DrawableHoldNote>(10, 50);
            RegisterPool<HeadNote, DrawableHoldNoteHead>(10, 50);
            RegisterPool<TailNote, DrawableHoldNoteTail>(10, 50);
        }

        private void onSourceChanged()
        {
            AccentColour.Value = skin.GetManiaSkinConfig<Color4>(LegacyManiaSkinConfigurationLookups.ColumnBackgroundColour, Index)?.Value ?? Color4.Black;
        }

        protected override void LoadComplete()
        {
            base.LoadComplete();
            NewResult += OnNewResult;
        }

        protected override void Dispose(bool isDisposing)
        {
            // must happen before children are disposed in base call to prevent illegal accesses to the hit explosion pool.
            NewResult -= OnNewResult;

            base.Dispose(isDisposing);

            if (skin != null)
                skin.SourceChanged -= onSourceChanged;
        }

        protected override IReadOnlyDependencyContainer CreateChildDependencies(IReadOnlyDependencyContainer parent)
        {
            var dependencies = new DependencyContainer(base.CreateChildDependencies(parent));
            dependencies.CacheAs<IBindable<ManiaAction>>(Action);
            return dependencies;
        }

        protected override void OnNewDrawableHitObject(DrawableHitObject drawableHitObject)
        {
            base.OnNewDrawableHitObject(drawableHitObject);

            DrawableManiaHitObject maniaObject = (DrawableManiaHitObject)drawableHitObject;

            maniaObject.AccentColour.BindTo(AccentColour);
            maniaObject.CheckHittable = hitPolicy.IsHittable;
        }

        internal void OnNewResult(DrawableHitObject judgedObject, JudgementResult result)
        {
            if (result.IsHit)
                hitPolicy.HandleHit(judgedObject);

            if (!result.IsHit || !judgedObject.DisplayResult || !DisplayJudgements.Value)
                return;

            HitObjectArea.Explosions.Add(hitExplosionPool.Get(e => e.Apply(result)));
        }

        public bool OnPressed(KeyBindingPressEvent<ManiaAction> e)
        {
            if (e.Action != Action.Value)
                return false;

            sampleTriggerSource.Play();
            return true;
        }

        public void OnReleased(KeyBindingReleaseEvent<ManiaAction> e)
        {
        }

        public override bool ReceivePositionalInputAt(Vector2 screenSpacePos)
            // This probably shouldn't exist as is, but the columns in the stage are separated by a 1px border
            => DrawRectangle.Inflate(new Vector2(Stage.COLUMN_SPACING / 2, 0)).Contains(ToLocalSpace(screenSpacePos));

        public partial class ColumnTouchInputArea : Drawable
        {
            private readonly Column column;

            [Resolved(canBeNull: true)]
            private ManiaInputManager maniaInputManager { get; set; }

            private KeyBindingContainer<ManiaAction> keyBindingContainer;

            public ColumnTouchInputArea(Column column)
            {
                RelativeSizeAxes = Axes.Both;

                this.column = column;
            }

            protected override void LoadComplete()
            {
                keyBindingContainer = maniaInputManager?.KeyBindingContainer;
            }

            protected override bool OnTouchDown(TouchDownEvent e)
            {
                keyBindingContainer?.TriggerPressed(column.Action.Value);
                return true;
            }

            protected override void OnTouchUp(TouchUpEvent e)
            {
                keyBindingContainer?.TriggerReleased(column.Action.Value);
            }
        }
    }
}