// 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 System.Collections.Generic;
using System.Linq;
using osu.Framework.Allocation;
using osu.Framework.Graphics;
using osu.Framework.Graphics.Containers;
using osu.Game.Rulesets.Judgements;
using osu.Game.Rulesets.Mania.Beatmaps;
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
{
    /// <summary>
    /// A collection of <see cref="Column"/>s.
    /// </summary>
    public class Stage : ScrollingPlayfield
    {
        public const float COLUMN_SPACING = 1;

        public const float HIT_TARGET_POSITION = 110;

        public IReadOnlyList<Column> Columns => columnFlow.Children;
        private readonly FillFlowContainer<Column> columnFlow;

        public Container<DrawableManiaJudgement> Judgements => judgements;
        private readonly JudgementContainer<DrawableManiaJudgement> judgements;

        private readonly Drawable barLineContainer;
        private readonly Container topLevelContainer;

        private readonly Dictionary<ColumnType, Color4> columnColours = new Dictionary<ColumnType, Color4>
        {
            { ColumnType.Even, new Color4(6, 84, 0, 255) },
            { ColumnType.Odd, new Color4(94, 0, 57, 255) },
            { ColumnType.Special, new Color4(0, 48, 63, 255) }
        };

        public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => Columns.Any(c => c.ReceivePositionalInputAt(screenSpacePos));

        private readonly int firstColumnIndex;

        public Stage(int firstColumnIndex, StageDefinition definition, ref ManiaAction normalColumnStartAction, ref ManiaAction specialColumnStartAction)
        {
            this.firstColumnIndex = firstColumnIndex;

            Name = "Stage";

            Anchor = Anchor.Centre;
            Origin = Anchor.Centre;
            RelativeSizeAxes = Axes.Y;
            AutoSizeAxes = Axes.X;

            InternalChildren = new Drawable[]
            {
                new Container
                {
                    Anchor = Anchor.TopCentre,
                    Origin = Anchor.TopCentre,
                    RelativeSizeAxes = Axes.Y,
                    AutoSizeAxes = Axes.X,
                    Children = new Drawable[]
                    {
                        new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageBackground), _ => new DefaultStageBackground())
                        {
                            RelativeSizeAxes = Axes.Both
                        },
                        columnFlow = new FillFlowContainer<Column>
                        {
                            Name = "Columns",
                            RelativeSizeAxes = Axes.Y,
                            AutoSizeAxes = Axes.X,
                            Direction = FillDirection.Horizontal,
                            Padding = new MarginPadding { Left = COLUMN_SPACING, Right = COLUMN_SPACING },
                        },
                        new Container
                        {
                            Name = "Barlines mask",
                            Anchor = Anchor.TopCentre,
                            Origin = Anchor.TopCentre,
                            RelativeSizeAxes = Axes.Y,
                            Width = 1366, // Bar lines should only be masked on the vertical axis
                            BypassAutoSizeAxes = Axes.Both,
                            Masking = true,
                            Child = barLineContainer = new HitObjectArea(HitObjectContainer)
                            {
                                Name = "Bar lines",
                                Anchor = Anchor.TopCentre,
                                Origin = Anchor.TopCentre,
                                RelativeSizeAxes = Axes.Y,
                            }
                        },
                        new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageForeground), _ => null)
                        {
                            RelativeSizeAxes = Axes.Both
                        },
                        judgements = new JudgementContainer<DrawableManiaJudgement>
                        {
                            Anchor = Anchor.TopCentre,
                            Origin = Anchor.Centre,
                            RelativeSizeAxes = Axes.Both,
                            Y = HIT_TARGET_POSITION + 150,
                        },
                        topLevelContainer = new Container { RelativeSizeAxes = Axes.Both }
                    }
                }
            };

            for (int i = 0; i < definition.Columns; i++)
            {
                var columnType = definition.GetTypeOfColumn(i);
                var column = new Column(firstColumnIndex + i)
                {
                    ColumnType = columnType,
                    AccentColour = columnColours[columnType],
                    Action = { Value = columnType == ColumnType.Special ? specialColumnStartAction++ : normalColumnStartAction++ }
                };

                AddColumn(column);
            }
        }

        private ISkin currentSkin;

        [BackgroundDependencyLoader]
        private void load(ISkinSource skin)
        {
            currentSkin = skin;
            skin.SourceChanged += onSkinChanged;

            onSkinChanged();
        }

        private void onSkinChanged()
        {
            foreach (var col in columnFlow)
            {
                if (col.Index > 0)
                {
                    float spacing = currentSkin.GetConfig<ManiaSkinConfigurationLookup, float>(
                                                   new ManiaSkinConfigurationLookup(LegacyManiaSkinConfigurationLookups.ColumnSpacing, col.Index - 1))
                                               ?.Value ?? COLUMN_SPACING;

                    col.Margin = new MarginPadding { Left = spacing };
                }

                float? width = currentSkin.GetConfig<ManiaSkinConfigurationLookup, float>(
                                              new ManiaSkinConfigurationLookup(LegacyManiaSkinConfigurationLookups.ColumnWidth, col.Index))
                                          ?.Value;

                if (width == null)
                    // only used by default skin (legacy skins get defaults set in LegacyManiaSkinConfiguration)
                    col.Width = col.IsSpecial ? Column.SPECIAL_COLUMN_WIDTH : Column.COLUMN_WIDTH;
                else
                    col.Width = width.Value;
            }
        }

        public void AddColumn(Column c)
        {
            topLevelContainer.Add(c.TopLevelContainer.CreateProxy());
            columnFlow.Add(c);
            AddNested(c);
        }

        public override void Add(DrawableHitObject h)
        {
            var maniaObject = (ManiaHitObject)h.HitObject;

            int columnIndex = -1;

            maniaObject.ColumnBindable.BindValueChanged(_ =>
            {
                if (columnIndex != -1)
                    Columns.ElementAt(columnIndex).Remove(h);

                columnIndex = maniaObject.Column - firstColumnIndex;
                Columns.ElementAt(columnIndex).Add(h);
            }, true);

            h.OnNewResult += OnNewResult;
        }

        public override bool Remove(DrawableHitObject h)
        {
            var maniaObject = (ManiaHitObject)h.HitObject;
            int columnIndex = maniaObject.Column - firstColumnIndex;
            Columns.ElementAt(columnIndex).Remove(h);

            h.OnNewResult -= OnNewResult;
            return true;
        }

        public void Add(BarLine barline) => base.Add(new DrawableBarLine(barline));

        internal void OnNewResult(DrawableHitObject judgedObject, JudgementResult result)
        {
            if (!judgedObject.DisplayResult || !DisplayJudgements.Value)
                return;

            judgements.Clear();
            judgements.Add(new DrawableManiaJudgement(result, judgedObject)
            {
                Anchor = Anchor.Centre,
                Origin = Anchor.Centre,
            });
        }

        protected override void Update()
        {
            // Due to masking differences, it is not possible to get the width of the columns container automatically
            // While masking on effectively only the Y-axis, so we need to set the width of the bar line container manually
            barLineContainer.Width = columnFlow.Width;
        }
    }
}