// 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;
using System.Collections.Generic;
using System.Linq;
using osu.Framework.Allocation;
using osu.Framework.Bindables;
using osu.Framework.Extensions.LocalisationExtensions;
using osu.Framework.Graphics;
using osu.Framework.Graphics.Containers;
using osu.Framework.Graphics.Effects;
using osu.Framework.Graphics.Shapes;
using osu.Framework.Graphics.Sprites;
using osu.Framework.Graphics.UserInterface;
using osu.Game.Configuration;
using osu.Game.Graphics;
using osu.Game.Graphics.Sprites;
using osu.Game.Localisation;
using osu.Game.Overlays;
using osu.Game.Rulesets.Mods;
using osu.Game.Screens.Play.HUD;
using osu.Game.Utils;
using osuTK;
using osuTK.Graphics;

namespace osu.Game.Screens.Select.FooterV2
{
    public partial class FooterButtonModsV2 : FooterButtonV2, IHasCurrentValue<IReadOnlyList<Mod>>
    {
        // todo: see https://github.com/ppy/osu-framework/issues/3271
        private const float torus_scale_factor = 1.2f;

        private readonly BindableWithCurrent<IReadOnlyList<Mod>> current = new BindableWithCurrent<IReadOnlyList<Mod>>(Array.Empty<Mod>());

        public Bindable<IReadOnlyList<Mod>> Current
        {
            get => current.Current;
            set => current.Current = value;
        }

        private Container modDisplayBar = null!;

        protected Container UnrankedBadge { get; private set; } = null!;

        private ModDisplay modDisplay = null!;
        private OsuSpriteText modCountText = null!;

        protected OsuSpriteText MultiplierText { get; private set; } = null!;

        [Resolved]
        private OsuColour colours { get; set; } = null!;

        [Resolved]
        private OverlayColourProvider colourProvider { get; set; } = null!;

        [BackgroundDependencyLoader]
        private void load()
        {
            const float bar_shear_width = 7f;
            const float bar_height = 37f;
            const float display_rel_width = 0.65f;

            var barShear = new Vector2(bar_shear_width / bar_height, 0);

            Text = "Mods";
            Icon = FontAwesome.Solid.ExchangeAlt;
            AccentColour = colours.Lime1;

            AddRange(new[]
            {
                UnrankedBadge = new Container
                {
                    Position = new Vector2(BUTTON_WIDTH + 5f, -5f),
                    Depth = float.MaxValue,
                    Origin = Anchor.BottomLeft,
                    Shear = barShear,
                    CornerRadius = CORNER_RADIUS,
                    AutoSizeAxes = Axes.Both,
                    Masking = true,
                    BorderColour = Color4.White,
                    BorderThickness = 2f,
                    Children = new Drawable[]
                    {
                        new Box
                        {
                            Colour = colours.Red2,
                            RelativeSizeAxes = Axes.Both,
                        },
                        new OsuSpriteText
                        {
                            Shear = -barShear,
                            Text = ModSelectOverlayStrings.Unranked.ToUpper(),
                            Margin = new MarginPadding { Horizontal = 15, Vertical = 5 },
                            Font = OsuFont.Torus.With(size: 14 * torus_scale_factor, weight: FontWeight.Bold),
                            Colour = Color4.Black,
                        }
                    }
                },
                modDisplayBar = new Container
                {
                    Y = -5f,
                    Depth = float.MaxValue,
                    Origin = Anchor.BottomLeft,
                    Shear = barShear,
                    CornerRadius = CORNER_RADIUS,
                    Size = new Vector2(BUTTON_WIDTH, bar_height),
                    Masking = true,
                    EdgeEffect = new EdgeEffectParameters
                    {
                        Type = EdgeEffectType.Shadow,
                        Radius = 4,
                        // Figma says 50% opacity, but it does not match up visually if taken at face value, and looks bad.
                        Colour = Colour4.Black.Opacity(0.25f),
                        Offset = new Vector2(0, 2),
                    },
                    Children = new Drawable[]
                    {
                        new Box
                        {
                            Colour = colourProvider.Background4,
                            RelativeSizeAxes = Axes.Both,
                        },
                        new Container
                        {
                            Anchor = Anchor.CentreRight,
                            Origin = Anchor.CentreRight,
                            RelativeSizeAxes = Axes.Both,
                            Width = 1f - display_rel_width,
                            Masking = true,
                            Child = MultiplierText = new OsuSpriteText
                            {
                                Anchor = Anchor.Centre,
                                Origin = Anchor.Centre,
                                Shear = -barShear,
                                Font = OsuFont.Torus.With(size: 14 * torus_scale_factor, weight: FontWeight.Bold)
                            }
                        },
                        new Container
                        {
                            CornerRadius = CORNER_RADIUS,
                            RelativeSizeAxes = Axes.Both,
                            Width = display_rel_width,
                            Masking = true,
                            Children = new Drawable[]
                            {
                                new Box
                                {
                                    Colour = colourProvider.Background3,
                                    RelativeSizeAxes = Axes.Both,
                                },
                                modDisplay = new ModDisplay(showExtendedInformation: false)
                                {
                                    Anchor = Anchor.Centre,
                                    Origin = Anchor.Centre,
                                    Shear = -barShear,
                                    Scale = new Vector2(0.6f),
                                    Current = { Value = new List<Mod> { new ModCinema() } },
                                    ExpansionMode = ExpansionMode.AlwaysContracted,
                                },
                                modCountText = new OsuSpriteText
                                {
                                    Anchor = Anchor.Centre,
                                    Origin = Anchor.Centre,
                                    Shear = -barShear,
                                    Font = OsuFont.Torus.With(size: 14 * torus_scale_factor, weight: FontWeight.Bold),
                                }
                            }
                        },
                    }
                },
            });
        }

        private ModSettingChangeTracker? modSettingChangeTracker;

        protected override void LoadComplete()
        {
            base.LoadComplete();

            Current.BindValueChanged(m =>
            {
                modSettingChangeTracker?.Dispose();

                updateDisplay();

                if (m.NewValue != null)
                {
                    modSettingChangeTracker = new ModSettingChangeTracker(m.NewValue);
                    modSettingChangeTracker.SettingChanged += _ => updateDisplay();
                }
            }, true);

            FinishTransforms(true);
        }

        private const double duration = 240;
        private const Easing easing = Easing.OutQuint;

        private void updateDisplay()
        {
            if (Current.Value.Count == 0)
            {
                modDisplayBar.MoveToY(20, duration, easing);
                modDisplayBar.FadeOut(duration, easing);
                modDisplay.FadeOut(duration, easing);
                modCountText.FadeOut(duration, easing);

                UnrankedBadge.MoveToY(20, duration, easing);
                UnrankedBadge.FadeOut(duration, easing);

                // add delay to let unranked indicator hide first before resizing the button back to its original width.
                this.Delay(duration).ResizeWidthTo(BUTTON_WIDTH, duration, easing);
            }
            else
            {
                if (Current.Value.Count >= 5)
                {
                    modCountText.Text = $"{Current.Value.Count} MODS";
                    modCountText.FadeIn(duration, easing);
                    modDisplay.FadeOut(duration, easing);
                }
                else
                {
                    modDisplay.Current.Value = Current.Value;
                    modDisplay.FadeIn(duration, easing);
                    modCountText.FadeOut(duration, easing);
                }

                if (Current.Value.Any(m => !m.Ranked))
                {
                    UnrankedBadge.MoveToX(BUTTON_WIDTH + 5, duration, easing);
                    UnrankedBadge.FadeIn(duration, easing);

                    this.ResizeWidthTo(BUTTON_WIDTH + UnrankedBadge.DrawWidth + 10, duration, easing);
                }
                else
                {
                    UnrankedBadge.MoveToX(BUTTON_WIDTH + 5 - UnrankedBadge.DrawWidth, duration, easing);
                    UnrankedBadge.FadeOut(duration, easing);

                    this.ResizeWidthTo(BUTTON_WIDTH, duration, easing);
                }

                modDisplayBar.MoveToY(-5, duration, Easing.OutQuint);
                UnrankedBadge.MoveToY(-5, duration, easing);
                modDisplayBar.FadeIn(duration, easing);
            }

            double multiplier = Current.Value?.Aggregate(1.0, (current, mod) => current * mod.ScoreMultiplier) ?? 1;
            MultiplierText.Text = ModUtils.FormatScoreMultiplier(multiplier);

            if (multiplier > 1)
                MultiplierText.FadeColour(colours.Red1, duration, easing);
            else if (multiplier < 1)
                MultiplierText.FadeColour(colours.Lime1, duration, easing);
            else
                MultiplierText.FadeColour(Color4.White, duration, easing);
        }
    }
}