// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE

using System;
using osu.Framework.Allocation;
using osu.Framework.Audio;
using osu.Framework.Audio.Sample;
using osu.Framework.Audio.Track;
using osu.Framework.Graphics;
using osu.Framework.Graphics.Containers;
using osu.Framework.Graphics.Shapes;
using osu.Framework.Graphics.Sprites;
using osu.Framework.Graphics.Textures;
using osu.Framework.Input.EventArgs;
using osu.Framework.Input.States;
using osu.Framework.MathUtils;
using osu.Game.Beatmaps.ControlPoints;
using osu.Game.Graphics;
using osu.Game.Graphics.Backgrounds;
using osu.Game.Graphics.Containers;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Input;

namespace osu.Game.Screens.Menu
{
    /// <summary>
    /// osu! logo and its attachments (pulsing, visualiser etc.)
    /// </summary>
    public class OsuLogo : BeatSyncedContainer
    {
        public readonly Color4 OsuPink = OsuColour.FromHex(@"e967a1");

        private const double transition_length = 300;

        private readonly Sprite logo;
        private readonly CircularContainer logoContainer;
        private readonly Container logoBounceContainer;
        private readonly Container logoBeatContainer;
        private readonly Container logoAmplitudeContainer;
        private readonly Container logoHoverContainer;
        private readonly LogoVisualisation visualizer;

        private readonly IntroSequence intro;

        private SampleChannel sampleClick;
        private SampleChannel sampleBeat;

        private readonly Container colourAndTriangles;

        private readonly Triangles triangles;

        /// <summary>
        /// Return value decides whether the logo should play its own sample for the click action.
        /// </summary>
        public Func<bool> Action;

        public float SizeForFlow => logo == null ? 0 : logo.DrawSize.X * logo.Scale.X * logoBounceContainer.Scale.X * logoHoverContainer.Scale.X * 0.74f;

        private readonly Sprite ripple;

        private readonly Container rippleContainer;

        public bool Triangles
        {
            set { colourAndTriangles.FadeTo(value ? 1 : 0, transition_length, Easing.OutQuint); }
        }

        public bool BeatMatching = true;

        public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => logoContainer.ReceivePositionalInputAt(screenSpacePos);

        public bool Ripple
        {
            get { return rippleContainer.Alpha > 0; }
            set { rippleContainer.FadeTo(value ? 1 : 0, transition_length, Easing.OutQuint); }
        }

        private readonly Box flashLayer;

        private readonly Container impactContainer;

        private const float default_size = 480;

        private const double early_activation = 60;

        public override bool IsPresent => base.IsPresent || Scheduler.HasPendingTasks;

        public OsuLogo()
        {
            EarlyActivationMilliseconds = early_activation;

            Size = new Vector2(default_size);

            Origin = Anchor.Centre;

            AutoSizeAxes = Axes.Both;

            Children = new Drawable[]
            {
                intro = new IntroSequence
                {
                    RelativeSizeAxes = Axes.Both,
                },
                logoHoverContainer = new Container
                {
                    AutoSizeAxes = Axes.Both,
                    Children = new Drawable[]
                    {
                        logoBounceContainer = new Container
                        {
                            AutoSizeAxes = Axes.Both,
                            Children = new Drawable[]
                            {
                                rippleContainer = new Container
                                {
                                    Anchor = Anchor.Centre,
                                    Origin = Anchor.Centre,
                                    RelativeSizeAxes = Axes.Both,
                                    Children = new Drawable[]
                                    {
                                        ripple = new Sprite
                                        {
                                            Anchor = Anchor.Centre,
                                            Origin = Anchor.Centre,
                                            Blending = BlendingMode.Additive,
                                            Alpha = 0
                                        }
                                    }
                                },
                                logoAmplitudeContainer = new Container
                                {
                                    AutoSizeAxes = Axes.Both,
                                    Children = new Drawable[]
                                    {
                                        logoBeatContainer = new Container
                                        {
                                            AutoSizeAxes = Axes.Both,
                                            Children = new Drawable[]
                                            {
                                                visualizer = new LogoVisualisation
                                                {
                                                    RelativeSizeAxes = Axes.Both,
                                                    Origin = Anchor.Centre,
                                                    Anchor = Anchor.Centre,
                                                    Alpha = 0.5f,
                                                    Size = new Vector2(0.96f)
                                                },
                                                new Container
                                                {
                                                    AutoSizeAxes = Axes.Both,
                                                    Children = new Drawable[]
                                                    {
                                                        logoContainer = new CircularContainer
                                                        {
                                                            Anchor = Anchor.Centre,
                                                            Origin = Anchor.Centre,
                                                            RelativeSizeAxes = Axes.Both,
                                                            Scale = new Vector2(0.88f),
                                                            Masking = true,
                                                            Children = new Drawable[]
                                                            {
                                                                colourAndTriangles = new Container
                                                                {
                                                                    RelativeSizeAxes = Axes.Both,
                                                                    Anchor = Anchor.Centre,
                                                                    Origin = Anchor.Centre,
                                                                    Children = new Drawable[]
                                                                    {
                                                                        new Box
                                                                        {
                                                                            RelativeSizeAxes = Axes.Both,
                                                                            Colour = OsuPink,
                                                                        },
                                                                        triangles = new Triangles
                                                                        {
                                                                            TriangleScale = 4,
                                                                            ColourLight = OsuColour.FromHex(@"ff7db7"),
                                                                            ColourDark = OsuColour.FromHex(@"de5b95"),
                                                                            RelativeSizeAxes = Axes.Both,
                                                                        },
                                                                    }
                                                                },
                                                                flashLayer = new Box
                                                                {
                                                                    RelativeSizeAxes = Axes.Both,
                                                                    Blending = BlendingMode.Additive,
                                                                    Colour = Color4.White,
                                                                    Alpha = 0,
                                                                },
                                                            },
                                                        },
                                                        logo = new Sprite
                                                        {
                                                            Anchor = Anchor.Centre,
                                                            Origin = Anchor.Centre,
                                                        },
                                                    }
                                                },
                                                impactContainer = new CircularContainer
                                                {
                                                    Anchor = Anchor.Centre,
                                                    Origin = Anchor.Centre,
                                                    Alpha = 0,
                                                    BorderColour = Color4.White,
                                                    RelativeSizeAxes = Axes.Both,
                                                    BorderThickness = 10,
                                                    Masking = true,
                                                    Children = new Drawable[]
                                                    {
                                                        new Box
                                                        {
                                                            RelativeSizeAxes = Axes.Both,
                                                            AlwaysPresent = true,
                                                            Alpha = 0,
                                                        }
                                                    }
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            };
        }

        /// <summary>
        /// Schedule a new extenral animation. Handled queueing and finishing previous animations in a sane way.
        /// </summary>
        /// <param name="action">The animation to be performed</param>
        /// <param name="waitForPrevious">If true, the new animation is delayed until all previous transforms finish. If false, existing transformed are cleared.</param>
        public void AppendAnimatingAction(Action action, bool waitForPrevious)
        {
            void runnableAction()
            {
                if (waitForPrevious)
                    this.DelayUntilTransformsFinished().Schedule(action);
                else
                {
                    ClearTransforms();
                    action();
                }
            }

            if (IsLoaded)
                runnableAction();
            else
                Schedule(runnableAction);
        }

        [BackgroundDependencyLoader]
        private void load(TextureStore textures, AudioManager audio)
        {
            sampleClick = audio.Sample.Get(@"Menu/osu-logo-select");
            sampleBeat = audio.Sample.Get(@"Menu/osu-logo-heartbeat");

            logo.Texture = textures.Get(@"Menu/logo");
            ripple.Texture = textures.Get(@"Menu/logo");
        }

        private int lastBeatIndex;

        protected override void OnNewBeat(int beatIndex, TimingControlPoint timingPoint, EffectControlPoint effectPoint, TrackAmplitudes amplitudes)
        {
            base.OnNewBeat(beatIndex, timingPoint, effectPoint, amplitudes);

            if (!BeatMatching) return;

            lastBeatIndex = beatIndex;

            var beatLength = timingPoint.BeatLength;

            float amplitudeAdjust = Math.Min(1, 0.4f + amplitudes.Maximum);

            if (beatIndex < 0) return;

            if (IsHovered)
                this.Delay(early_activation).Schedule(() => sampleBeat.Play());

            logoBeatContainer
                .ScaleTo(1 - 0.02f * amplitudeAdjust, early_activation, Easing.Out)
                .Then()
                .ScaleTo(1, beatLength * 2, Easing.OutQuint);

            ripple.ClearTransforms();
            ripple
                .ScaleTo(logoAmplitudeContainer.Scale)
                .ScaleTo(logoAmplitudeContainer.Scale * (1 + 0.04f * amplitudeAdjust), beatLength, Easing.OutQuint)
                .FadeTo(0.15f * amplitudeAdjust).FadeOut(beatLength, Easing.OutQuint);

            if (effectPoint.KiaiMode && flashLayer.Alpha < 0.4f)
            {
                flashLayer.ClearTransforms();
                flashLayer
                    .FadeTo(0.2f * amplitudeAdjust, early_activation, Easing.Out)
                    .Then()
                    .FadeOut(beatLength);

                visualizer.ClearTransforms();
                visualizer
                    .FadeTo(0.9f * amplitudeAdjust, early_activation, Easing.Out)
                    .Then()
                    .FadeTo(0.5f, beatLength);
            }
        }

        public void PlayIntro()
        {
            const double length = 3150;
            const double fade = 200;

            logoHoverContainer.FadeOut().Delay(length).FadeIn(fade);
            intro.Show();
            intro.Start(length);
            intro.Delay(length + fade).FadeOut();
        }

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

            const float scale_adjust_cutoff = 0.4f;
            const float velocity_adjust_cutoff = 0.98f;
            const float paused_velocity = 0.5f;

            if (Beatmap.Value.Track.IsRunning)
            {
                var maxAmplitude = lastBeatIndex >= 0 ? Beatmap.Value.Track.CurrentAmplitudes.Maximum : 0;
                logoAmplitudeContainer.ScaleTo(1 - Math.Max(0, maxAmplitude - scale_adjust_cutoff) * 0.04f, 75, Easing.OutQuint);

                if (maxAmplitude > velocity_adjust_cutoff)
                    triangles.Velocity = 1 + Math.Max(0, maxAmplitude - velocity_adjust_cutoff) * 50;
                else
                    triangles.Velocity = (float)Interpolation.Damp(triangles.Velocity, 1, 0.995f, Time.Elapsed);
            }
            else
            {
                triangles.Velocity = paused_velocity;
            }
        }

        public override bool HandlePositionalInput => base.HandlePositionalInput && Action != null && Alpha > 0.2f;

        protected override bool OnMouseDown(InputState state, MouseDownEventArgs args)
        {
            if (args.Button != MouseButton.Left) return false;

            logoBounceContainer.ScaleTo(0.9f, 1000, Easing.Out);
            return true;
        }

        protected override bool OnMouseUp(InputState state, MouseUpEventArgs args)
        {
            if (args.Button != MouseButton.Left) return false;

            logoBounceContainer.ScaleTo(1f, 500, Easing.OutElastic);
            return true;
        }

        protected override bool OnClick(InputState state)
        {
            if (Action?.Invoke() ?? true)
                sampleClick.Play();

            flashLayer.ClearTransforms();
            flashLayer.Alpha = 0.4f;
            flashLayer.FadeOut(1500, Easing.OutExpo);
            return true;
        }

        protected override bool OnHover(InputState state)
        {
            logoHoverContainer.ScaleTo(1.1f, 500, Easing.OutElastic);
            return true;
        }

        protected override void OnHoverLost(InputState state)
        {
            logoHoverContainer.ScaleTo(1, 500, Easing.OutElastic);
        }

        public void Impact()
        {
            impactContainer.FadeOutFromOne(250, Easing.In);
            impactContainer.ScaleTo(0.96f);
            impactContainer.ScaleTo(1.12f, 250);
        }
    }
}