// 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 osu.Framework.Graphics;
using osu.Framework.Graphics.Textures;
using osu.Framework.Audio.Sample;
using osu.Framework.Bindables;
using osu.Game.Rulesets.Scoring;
using osu.Game.Audio;
using osu.Game.Beatmaps;
using osu.Game.Rulesets.Mania.Beatmaps;
using osu.Game.Skinning;
using System.Collections.Generic;

namespace osu.Game.Rulesets.Mania.Skinning
{
    public class ManiaLegacySkinTransformer : ISkin
    {
        private readonly ISkin source;
        private readonly ManiaBeatmap beatmap;

        /// <summary>
        /// Mapping of <see cref="HitResult"/> to ther corresponding
        /// <see cref="LegacyManiaSkinConfigurationLookups"/> value.
        /// </summary>
        private static readonly IReadOnlyDictionary<HitResult, LegacyManiaSkinConfigurationLookups> hitresult_mapping
            = new Dictionary<HitResult, LegacyManiaSkinConfigurationLookups>
            {
                { HitResult.Perfect, LegacyManiaSkinConfigurationLookups.Hit300g },
                { HitResult.Great, LegacyManiaSkinConfigurationLookups.Hit300 },
                { HitResult.Good, LegacyManiaSkinConfigurationLookups.Hit200 },
                { HitResult.Ok, LegacyManiaSkinConfigurationLookups.Hit100 },
                { HitResult.Meh, LegacyManiaSkinConfigurationLookups.Hit50 },
                { HitResult.Miss, LegacyManiaSkinConfigurationLookups.Hit0 }
            };

        /// <summary>
        /// Mapping of <see cref="HitResult"/> to their corresponding
        /// default filenames.
        /// </summary>
        private static readonly IReadOnlyDictionary<HitResult, string> default_hitresult_skin_filenames
            = new Dictionary<HitResult, string>
            {
                { HitResult.Perfect, "mania-hit300g" },
                { HitResult.Great, "mania-hit300" },
                { HitResult.Good, "mania-hit200" },
                { HitResult.Ok, "mania-hit100" },
                { HitResult.Meh, "mania-hit50" },
                { HitResult.Miss, "mania-hit0" }
            };

        private Lazy<bool> isLegacySkin;

        /// <summary>
        /// Whether texture for the keys exists.
        /// Used to determine if the mania ruleset is skinned.
        /// </summary>
        private Lazy<bool> hasKeyTexture;

        public ManiaLegacySkinTransformer(ISkinSource source, IBeatmap beatmap)
        {
            this.source = source;
            this.beatmap = (ManiaBeatmap)beatmap;

            source.SourceChanged += sourceChanged;
            sourceChanged();
        }

        private void sourceChanged()
        {
            isLegacySkin = new Lazy<bool>(() => source.GetConfig<LegacySkinConfiguration.LegacySetting, decimal>(LegacySkinConfiguration.LegacySetting.Version) != null);
            hasKeyTexture = new Lazy<bool>(() => source.GetAnimation(
                GetConfig<ManiaSkinConfigurationLookup, string>(
                    new ManiaSkinConfigurationLookup(LegacyManiaSkinConfigurationLookups.KeyImage, 0))?.Value
                ?? "mania-key1", true, true) != null);
        }

        public Drawable GetDrawableComponent(ISkinComponent component)
        {
            if (!isLegacySkin.Value || !hasKeyTexture.Value)
                return null;

            switch (component)
            {
                case GameplaySkinComponent<HitResult> resultComponent:
                    return getResult(resultComponent.Component);

                case ManiaSkinComponent maniaComponent:
                    switch (maniaComponent.Component)
                    {
                        case ManiaSkinComponents.ColumnBackground:
                            return new LegacyColumnBackground(maniaComponent.TargetColumn == beatmap.TotalColumns - 1);

                        case ManiaSkinComponents.HitTarget:
                            return new LegacyHitTarget();

                        case ManiaSkinComponents.KeyArea:
                            return new LegacyKeyArea();

                        case ManiaSkinComponents.Note:
                            return new LegacyNotePiece();

                        case ManiaSkinComponents.HoldNoteHead:
                            return new LegacyHoldNoteHeadPiece();

                        case ManiaSkinComponents.HoldNoteTail:
                            return new LegacyHoldNoteTailPiece();

                        case ManiaSkinComponents.HoldNoteBody:
                            return new LegacyBodyPiece();

                        case ManiaSkinComponents.HitExplosion:
                            return new LegacyHitExplosion();

                        case ManiaSkinComponents.StageBackground:
                            return new LegacyStageBackground();

                        case ManiaSkinComponents.StageForeground:
                            return new LegacyStageForeground();
                    }

                    break;
            }

            return null;
        }

        private Drawable getResult(HitResult result)
        {
            string image = GetConfig<ManiaSkinConfigurationLookup, string>(
                new ManiaSkinConfigurationLookup(hitresult_mapping[result])
            )?.Value ?? default_hitresult_skin_filenames[result];

            return this.GetAnimation(image, true, true);
        }

        public Texture GetTexture(string componentName) => source.GetTexture(componentName);

        public SampleChannel GetSample(ISampleInfo sample) => source.GetSample(sample);

        public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup)
        {
            if (lookup is ManiaSkinConfigurationLookup maniaLookup)
                return source.GetConfig<LegacyManiaSkinConfigurationLookup, TValue>(new LegacyManiaSkinConfigurationLookup(beatmap.TotalColumns, maniaLookup.Lookup, maniaLookup.TargetColumn));

            return source.GetConfig<TLookup, TValue>(lookup);
        }
    }
}