BeatmapInfoExtensions.cs

// 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.Linq;
using osu.Framework.Localisation;
using osu.Game.Online.API;
using osu.Game.Rulesets;
using osu.Game.Rulesets.Objects.Types;
using osu.Game.Screens.Select;

namespace osu.Game.Beatmaps
{
    public static class BeatmapInfoExtensions
    {
        /// <summary>
        /// Given an <see cref="IBeatmap"/>, update length, BPM and object counts.
        /// </summary>
        public static void UpdateStatisticsFromBeatmap(this BeatmapInfo beatmapInfo, IBeatmap beatmap)
        {
            beatmapInfo.Length = beatmap.CalculatePlayableLength();
            beatmapInfo.BPM = 60000 / beatmap.GetMostCommonBeatLength();
            beatmapInfo.EndTimeObjectCount = beatmap.HitObjects.Count(h => h is IHasDuration);
            beatmapInfo.TotalObjectCount = beatmap.HitObjects.Count;

            // Compute the maximum repeat count for pool sizing purposes.
            // RepeatCount is set during decoding and is available on the raw (pre-ApplyDefaults) beatmap,
            // so this can be derived without a full conversion pass.
            beatmapInfo.MaxSliderRepeats = beatmap.HitObjects
                                                   .OfType<IHasRepeats>()
                                                   .Select(h => h.RepeatCount)
                                                   .DefaultIfEmpty(0)
                                                   .Max();

            // Slider tick objects are generated as nested hit objects after defaults have been applied.
            // This method is called both with raw and playable beatmaps; for raw beatmaps this will
            // naturally become 0 and later be backfilled by background processing.
            beatmapInfo.MaxSliderTicks = beatmap.HitObjects
                                                .Select(h => h.NestedHitObjects.Count(n => n is ISliderTick))
                                                .DefaultIfEmpty(0)
                                                .Max();
        }

        /// <summary>
        /// A user-presentable display title representing this beatmap.
        /// </summary>
        public static string GetDisplayTitle(this IBeatmapInfo beatmapInfo) => $"{beatmapInfo.Metadata.GetDisplayTitle()} {getVersionString(beatmapInfo)}".Trim();

        /// <summary>
        /// A user-presentable display title representing this beatmap, with localisation handling for potentially romanisable fields.
        /// </summary>
        public static RomanisableString GetDisplayTitleRomanisable(this IBeatmapInfo beatmapInfo, bool includeDifficultyName = true, bool includeCreator = true)
        {
            var metadata = beatmapInfo.Metadata.GetDisplayTitleRomanisable(includeCreator);

            if (includeDifficultyName)
            {
                string versionString = getVersionString(beatmapInfo);
                return new RomanisableString($"{metadata.GetPreferred(true)} {versionString}".Trim(), $"{metadata.GetPreferred(false)} {versionString}".Trim());
            }

            return new RomanisableString($"{metadata.GetPreferred(true)}".Trim(), $"{metadata.GetPreferred(false)}".Trim());
        }

        public static bool Match(this IBeatmapInfo beatmapInfo, params FilterCriteria.OptionalTextFilter[] filters)
        {
            foreach (var filter in filters)
            {
                if (filter.Matches(beatmapInfo.DifficultyName))
                    continue;

                if (BeatmapMetadataInfoExtensions.Match(beatmapInfo.Metadata, filter))
                    continue;

                // failed to match a single filter at all - fail the whole match.
                return false;
            }

            // got through all filters without failing any - pass the whole match.
            return true;
        }

        private static string getVersionString(IBeatmapInfo beatmapInfo) => string.IsNullOrEmpty(beatmapInfo.DifficultyName) ? string.Empty : $"[{beatmapInfo.DifficultyName}]";

        /// <summary>
        /// Whether gameplay is allowed for this beatmap with the provided ruleset (via conversion or direct compatibility).
        /// </summary>
        public static bool AllowGameplayWithRuleset(this IBeatmapInfo beatmap, RulesetInfo ruleset, bool allowConversion)
        {
            if (beatmap.Ruleset.ShortName == ruleset.ShortName)
                return true;

            if (allowConversion && beatmap.Ruleset.OnlineID == 0 && ruleset.OnlineID != 0)
                return true;

            return false;
        }

        /// <summary>
        /// Get the beatmap info page URL, or <c>null</c> if unavailable.
        /// </summary>
        public static string? GetOnlineURL(this IBeatmapInfo beatmapInfo, IAPIProvider api, IRulesetInfo? ruleset = null)
        {
            if (beatmapInfo.OnlineID <= 0 || beatmapInfo.BeatmapSet == null)
                return null;

            return $@"{api.Endpoints.WebsiteUrl}/beatmapsets/{beatmapInfo.BeatmapSet.OnlineID}#{ruleset?.ShortName ?? beatmapInfo.Ruleset.ShortName}/{beatmapInfo.OnlineID}";
        }
    }
}