add AssetName to encapsulate asset name handling (#766)

17 files changed, 439 insertions, 316 deletions

diff --git a/src/SMAPI/Framework/Content/AssetData.cs b/src/SMAPI/Framework/Content/AssetData.cs
index 5c90d83b..05be8a3b 100644
--- a/src/SMAPI/Framework/Content/AssetData.cs
+++ b/src/SMAPI/Framework/Content/AssetData.cs
@@ -25,11 +25,11 @@ namespace StardewModdingAPI.Framework.Content
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="locale">The content's locale code, if the content is localized.</param>
-        /// <param name="assetName">The normalized asset name being read.</param>
+        /// <param name="assetName">The asset name being read.</param>
         /// <param name="data">The content data being read.</param>
         /// <param name="getNormalizedPath">Normalizes an asset key to match the cache key.</param>
         /// <param name="onDataReplaced">A callback to invoke when the data is replaced (if any).</param>
-        public AssetData(string locale, string assetName, TValue data, Func<string, string> getNormalizedPath, Action<TValue> onDataReplaced)
+        public AssetData(string locale, IAssetName assetName, TValue data, Func<string, string> getNormalizedPath, Action<TValue> onDataReplaced)
             : base(locale, assetName, data.GetType(), getNormalizedPath)
         {
             this.Data = data;
diff --git a/src/SMAPI/Framework/Content/AssetDataForDictionary.cs b/src/SMAPI/Framework/Content/AssetDataForDictionary.cs
index 26cbff5a..735b651c 100644
--- a/src/SMAPI/Framework/Content/AssetDataForDictionary.cs
+++ b/src/SMAPI/Framework/Content/AssetDataForDictionary.cs
@@ -11,11 +11,11 @@ namespace StardewModdingAPI.Framework.Content
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="locale">The content's locale code, if the content is localized.</param>
-        /// <param name="assetName">The normalized asset name being read.</param>
+        /// <param name="assetName">The asset name being read.</param>
         /// <param name="data">The content data being read.</param>
         /// <param name="getNormalizedPath">Normalizes an asset key to match the cache key.</param>
         /// <param name="onDataReplaced">A callback to invoke when the data is replaced (if any).</param>
-        public AssetDataForDictionary(string locale, string assetName, IDictionary<TKey, TValue> data, Func<string, string> getNormalizedPath, Action<IDictionary<TKey, TValue>> onDataReplaced)
+        public AssetDataForDictionary(string locale, IAssetName assetName, IDictionary<TKey, TValue> data, Func<string, string> getNormalizedPath, Action<IDictionary<TKey, TValue>> onDataReplaced)
             : base(locale, assetName, data, getNormalizedPath, onDataReplaced) { }
     }
 }
diff --git a/src/SMAPI/Framework/Content/AssetDataForImage.cs b/src/SMAPI/Framework/Content/AssetDataForImage.cs
index c75514bc..b0f1b5c7 100644
--- a/src/SMAPI/Framework/Content/AssetDataForImage.cs
+++ b/src/SMAPI/Framework/Content/AssetDataForImage.cs
@@ -21,11 +21,11 @@ namespace StardewModdingAPI.Framework.Content
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="locale">The content's locale code, if the content is localized.</param>
-        /// <param name="assetName">The normalized asset name being read.</param>
+        /// <param name="assetName">The asset name being read.</param>
         /// <param name="data">The content data being read.</param>
         /// <param name="getNormalizedPath">Normalizes an asset key to match the cache key.</param>
         /// <param name="onDataReplaced">A callback to invoke when the data is replaced (if any).</param>
-        public AssetDataForImage(string locale, string assetName, Texture2D data, Func<string, string> getNormalizedPath, Action<Texture2D> onDataReplaced)
+        public AssetDataForImage(string locale, IAssetName assetName, Texture2D data, Func<string, string> getNormalizedPath, Action<Texture2D> onDataReplaced)
             : base(locale, assetName, data, getNormalizedPath, onDataReplaced) { }
 
         /// <inheritdoc />
diff --git a/src/SMAPI/Framework/Content/AssetDataForMap.cs b/src/SMAPI/Framework/Content/AssetDataForMap.cs
index 0a5fa7e7..26e4986e 100644
--- a/src/SMAPI/Framework/Content/AssetDataForMap.cs
+++ b/src/SMAPI/Framework/Content/AssetDataForMap.cs
@@ -18,11 +18,11 @@ namespace StardewModdingAPI.Framework.Content
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="locale">The content's locale code, if the content is localized.</param>
-        /// <param name="assetName">The normalized asset name being read.</param>
+        /// <param name="assetName">The asset name being read.</param>
         /// <param name="data">The content data being read.</param>
         /// <param name="getNormalizedPath">Normalizes an asset key to match the cache key.</param>
         /// <param name="onDataReplaced">A callback to invoke when the data is replaced (if any).</param>
-        public AssetDataForMap(string locale, string assetName, Map data, Func<string, string> getNormalizedPath, Action<Map> onDataReplaced)
+        public AssetDataForMap(string locale, IAssetName assetName, Map data, Func<string, string> getNormalizedPath, Action<Map> onDataReplaced)
             : base(locale, assetName, data, getNormalizedPath, onDataReplaced) { }
 
         /// <inheritdoc />
diff --git a/src/SMAPI/Framework/Content/AssetDataForObject.cs b/src/SMAPI/Framework/Content/AssetDataForObject.cs
index b7e8dfeb..d91873ae 100644
--- a/src/SMAPI/Framework/Content/AssetDataForObject.cs
+++ b/src/SMAPI/Framework/Content/AssetDataForObject.cs
@@ -13,10 +13,10 @@ namespace StardewModdingAPI.Framework.Content
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="locale">The content's locale code, if the content is localized.</param>
-        /// <param name="assetName">The normalized asset name being read.</param>
+        /// <param name="assetName">The asset name being read.</param>
         /// <param name="data">The content data being read.</param>
         /// <param name="getNormalizedPath">Normalizes an asset key to match the cache key.</param>
-        public AssetDataForObject(string locale, string assetName, object data, Func<string, string> getNormalizedPath)
+        public AssetDataForObject(string locale, IAssetName assetName, object data, Func<string, string> getNormalizedPath)
             : base(locale, assetName, data, getNormalizedPath, onDataReplaced: null) { }
 
         /// <summary>Construct an instance.</summary>
@@ -24,24 +24,24 @@ namespace StardewModdingAPI.Framework.Content
         /// <param name="data">The content data being read.</param>
         /// <param name="getNormalizedPath">Normalizes an asset key to match the cache key.</param>
         public AssetDataForObject(IAssetInfo info, object data, Func<string, string> getNormalizedPath)
-            : this(info.Locale, info.AssetName, data, getNormalizedPath) { }
+            : this(info.Locale, info.Name, data, getNormalizedPath) { }
 
         /// <inheritdoc />
         public IAssetDataForDictionary<TKey, TValue> AsDictionary<TKey, TValue>()
         {
-            return new AssetDataForDictionary<TKey, TValue>(this.Locale, this.AssetName, this.GetData<IDictionary<TKey, TValue>>(), this.GetNormalizedPath, this.ReplaceWith);
+            return new AssetDataForDictionary<TKey, TValue>(this.Locale, this.Name, this.GetData<IDictionary<TKey, TValue>>(), this.GetNormalizedPath, this.ReplaceWith);
         }
 
         /// <inheritdoc />
         public IAssetDataForImage AsImage()
         {
-            return new AssetDataForImage(this.Locale, this.AssetName, this.GetData<Texture2D>(), this.GetNormalizedPath, this.ReplaceWith);
+            return new AssetDataForImage(this.Locale, this.Name, this.GetData<Texture2D>(), this.GetNormalizedPath, this.ReplaceWith);
         }
 
         /// <inheritdoc />
         public IAssetDataForMap AsMap()
         {
-            return new AssetDataForMap(this.Locale, this.AssetName, this.GetData<Map>(), this.GetNormalizedPath, this.ReplaceWith);
+            return new AssetDataForMap(this.Locale, this.Name, this.GetData<Map>(), this.GetNormalizedPath, this.ReplaceWith);
         }
 
         /// <inheritdoc />
diff --git a/src/SMAPI/Framework/Content/AssetInfo.cs b/src/SMAPI/Framework/Content/AssetInfo.cs
index d8106439..6a5b4f31 100644
--- a/src/SMAPI/Framework/Content/AssetInfo.cs
+++ b/src/SMAPI/Framework/Content/AssetInfo.cs
@@ -20,7 +20,11 @@ namespace StardewModdingAPI.Framework.Content
         public string Locale { get; }
 
         /// <inheritdoc />
-        public string AssetName { get; }
+        public IAssetName Name { get; }
+
+        /// <inheritdoc />
+        [Obsolete($"Use {nameof(Name)} instead.")]
+        public string AssetName => this.Name.Name;
 
         /// <inheritdoc />
         public Type DataType { get; }
@@ -31,22 +35,22 @@ namespace StardewModdingAPI.Framework.Content
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="locale">The content's locale code, if the content is localized.</param>
-        /// <param name="assetName">The normalized asset name being read.</param>
+        /// <param name="assetName">The asset name being read.</param>
         /// <param name="type">The content type being read.</param>
         /// <param name="getNormalizedPath">Normalizes an asset key to match the cache key.</param>
-        public AssetInfo(string locale, string assetName, Type type, Func<string, string> getNormalizedPath)
+        public AssetInfo(string locale, IAssetName assetName, Type type, Func<string, string> getNormalizedPath)
         {
             this.Locale = locale;
-            this.AssetName = assetName;
+            this.Name = assetName;
             this.DataType = type;
             this.GetNormalizedPath = getNormalizedPath;
         }
 
         /// <inheritdoc />
+        [Obsolete($"Use {nameof(Name)}.{nameof(IAssetName.IsEquivalentTo)} instead.")]
         public bool AssetNameEquals(string path)
         {
-            path = this.GetNormalizedPath(path);
-            return this.AssetName.Equals(path, StringComparison.OrdinalIgnoreCase);
+            return this.Name.IsEquivalentTo(path);
         }
 
 
diff --git a/src/SMAPI/Framework/Content/AssetInterceptorChange.cs b/src/SMAPI/Framework/Content/AssetInterceptorChange.cs
index 10488b84..981eed40 100644
--- a/src/SMAPI/Framework/Content/AssetInterceptorChange.cs
+++ b/src/SMAPI/Framework/Content/AssetInterceptorChange.cs
@@ -70,7 +70,7 @@ namespace StardewModdingAPI.Framework.Content
                 }
                 catch (Exception ex)
                 {
-                    this.Mod.LogAsMod($"Mod failed when checking whether it could edit asset '{asset.AssetName}'. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
+                    this.Mod.LogAsMod($"Mod failed when checking whether it could edit asset '{asset.Name}'. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
                 }
             }
 
@@ -84,7 +84,7 @@ namespace StardewModdingAPI.Framework.Content
                 }
                 catch (Exception ex)
                 {
-                    this.Mod.LogAsMod($"Mod failed when checking whether it could load asset '{asset.AssetName}'. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
+                    this.Mod.LogAsMod($"Mod failed when checking whether it could load asset '{asset.Name}'. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
                 }
             }
 
diff --git a/src/SMAPI/Framework/Content/AssetName.cs b/src/SMAPI/Framework/Content/AssetName.cs
new file mode 100644
index 00000000..992647f8
--- /dev/null
+++ b/src/SMAPI/Framework/Content/AssetName.cs
@@ -0,0 +1,173 @@
+using System;
+using StardewModdingAPI.Toolkit.Utilities;
+using StardewValley;
+
+namespace StardewModdingAPI.Framework.Content
+{
+    /// <summary>An asset name that can be loaded through the content pipeline.</summary>
+    internal class AssetName : IAssetName
+    {
+        /*********
+        ** Fields
+        *********/
+        /// <summary>A lowercase version of <see cref="Name"/> used for consistent hash codes and equality checks.</summary>
+        private readonly string ComparableName;
+
+
+        /*********
+        ** Accessors
+        *********/
+        /// <inheritdoc />
+        public string Name { get; }
+
+        /// <inheritdoc />
+        public string BaseName { get; }
+
+        /// <inheritdoc />
+        public string LocaleCode { get; }
+
+        /// <inheritdoc />
+        public LocalizedContentManager.LanguageCode? LanguageCode { get; }
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="baseName">The base asset name without the locale code.</param>
+        /// <param name="localeCode">The locale code specified in the <see cref="Name"/>, if it's a valid code recognized by the game content.</param>
+        /// <param name="languageCode">The language code matching the <see cref="LocaleCode"/>, if applicable.</param>
+        public AssetName(string baseName, string localeCode, LocalizedContentManager.LanguageCode? languageCode)
+        {
+            // validate
+            if (string.IsNullOrWhiteSpace(baseName))
+                throw new ArgumentException("The asset name can't be null or empty.", nameof(baseName));
+            if (string.IsNullOrWhiteSpace(localeCode))
+                localeCode = null;
+
+            // set base values
+            this.BaseName = PathUtilities.NormalizeAssetName(baseName);
+            this.LocaleCode = localeCode;
+            this.LanguageCode = languageCode;
+
+            // set derived values
+            this.Name = localeCode != null
+                ? string.Concat(this.BaseName, '.', this.LocaleCode)
+                : this.BaseName;
+            this.ComparableName = this.Name.ToLowerInvariant();
+        }
+
+        /// <summary>Parse a raw asset name into an instance.</summary>
+        /// <param name="rawName">The raw asset name to parse.</param>
+        /// <param name="parseLocale">Get the language code for a given locale, if it's valid.</param>
+        /// <exception cref="ArgumentException">The <paramref name="rawName"/> is null or empty.</exception>
+        public static AssetName Parse(string rawName, Func<string, LocalizedContentManager.LanguageCode?> parseLocale)
+        {
+            if (string.IsNullOrWhiteSpace(rawName))
+                throw new ArgumentException("The asset name can't be null or empty.", nameof(rawName));
+
+            string baseName = rawName;
+            string localeCode = null;
+            LocalizedContentManager.LanguageCode? languageCode = null;
+
+            int lastPeriodIndex = rawName.LastIndexOf('.');
+            if (lastPeriodIndex > 0 && rawName.Length > lastPeriodIndex + 1)
+            {
+                string possibleLocaleCode = rawName[(lastPeriodIndex + 1)..];
+                LocalizedContentManager.LanguageCode? possibleLanguageCode = parseLocale(possibleLocaleCode);
+
+                if (possibleLanguageCode != null)
+                {
+                    baseName = rawName[..lastPeriodIndex];
+                    localeCode = possibleLocaleCode;
+                    languageCode = possibleLanguageCode;
+                }
+            }
+
+            return new AssetName(baseName, localeCode, languageCode);
+        }
+
+        /// <inheritdoc />
+        public bool IsEquivalentTo(string assetName, bool useBaseName = false)
+        {
+            // empty asset key is never equivalent
+            if (string.IsNullOrWhiteSpace(assetName))
+                return false;
+
+            assetName = PathUtilities.NormalizeAssetName(assetName);
+
+            string compareTo = useBaseName ? this.BaseName : this.Name;
+            return compareTo.Equals(assetName, StringComparison.OrdinalIgnoreCase);
+        }
+
+        /// <inheritdoc />
+        public bool StartsWith(string prefix, bool allowPartialWord = true, bool allowSubfolder = true)
+        {
+            // asset keys never start with null
+            if (prefix is null)
+                return false;
+
+            // asset keys can't have a leading slash, but NormalizeAssetName will trim them
+            {
+                string trimmed = prefix.TrimStart();
+                if (trimmed.StartsWith('/') || trimmed.StartsWith('\\'))
+                    return false;
+            }
+
+            // normalize prefix
+            {
+                string normalized = PathUtilities.NormalizeAssetName(prefix);
+
+                string trimmed = prefix.TrimEnd();
+                if (trimmed.EndsWith('/') || trimmed.EndsWith('\\'))
+                    normalized += PathUtilities.PreferredAssetSeparator;
+
+                prefix = normalized;
+            }
+
+            // compare
+            return
+                this.Name.StartsWith(prefix, StringComparison.OrdinalIgnoreCase)
+                && (
+                    allowPartialWord
+                    || this.Name.Length == prefix.Length
+                    || !char.IsLetterOrDigit(prefix[^1]) // last character in suffix is word separator
+                    || !char.IsLetterOrDigit(this.Name[prefix.Length]) // or first character after it is
+                )
+                && (
+                    allowSubfolder
+                    || this.Name.Length == prefix.Length
+                    || !this.Name[prefix.Length..].Contains(PathUtilities.PreferredAssetSeparator)
+                );
+        }
+
+
+        public bool IsDirectlyUnderPath(string assetFolder)
+        {
+            return this.StartsWith(assetFolder + "/", allowPartialWord: false, allowSubfolder: false);
+        }
+
+        /// <inheritdoc />
+        public bool Equals(IAssetName other)
+        {
+            return other switch
+            {
+                null => false,
+                AssetName otherImpl => this.ComparableName == otherImpl.ComparableName,
+                _ => StringComparer.OrdinalIgnoreCase.Equals(this.Name, other.Name)
+            };
+        }
+
+        /// <inheritdoc />
+        public override int GetHashCode()
+        {
+            return this.ComparableName.GetHashCode();
+        }
+
+        /// <inheritdoc />
+        public override string ToString()
+        {
+            return this.Name;
+        }
+    }
+}
diff --git a/src/SMAPI/Framework/ContentCoordinator.cs b/src/SMAPI/Framework/ContentCoordinator.cs
index 61cefd12..97a37b3f 100644
--- a/src/SMAPI/Framework/ContentCoordinator.cs
+++ b/src/SMAPI/Framework/ContentCoordinator.cs
@@ -248,6 +248,16 @@ namespace StardewModdingAPI.Framework
                 this.InvalidateCache((contentManager, key, type) => contentManager is GameContentManager);
         }
 
+        /// <summary>Parse a raw asset name.</summary>
+        /// <param name="rawName">The raw asset name to parse.</param>
+        /// <exception cref="ArgumentException">The <paramref name="rawName"/> is null or empty.</exception>
+        public AssetName ParseAssetName(string rawName)
+        {
+            return !string.IsNullOrWhiteSpace(rawName)
+                ? AssetName.Parse(rawName, parseLocale: locale => this.LocaleCodes.Value.TryGetValue(locale, out LocalizedContentManager.LanguageCode langCode) ? langCode : null)
+                : throw new ArgumentException("The asset name can't be null or empty.", nameof(rawName));
+        }
+
         /// <summary>Get whether this asset is mapped to a mod folder.</summary>
         /// <param name="key">The asset key.</param>
         public bool IsManagedAssetKey(string key)
@@ -306,11 +316,12 @@ namespace StardewModdingAPI.Framework
         /// <param name="predicate">Matches the asset keys to invalidate.</param>
         /// <param name="dispose">Whether to dispose invalidated assets. This should only be <c>true</c> when they're being invalidated as part of a dispose, to avoid crashing the game.</param>
         /// <returns>Returns the invalidated asset keys.</returns>
-        public IEnumerable<string> InvalidateCache(Func<IAssetInfo, bool> predicate, bool dispose = false)
+        public IEnumerable<IAssetName> InvalidateCache(Func<IAssetInfo, bool> predicate, bool dispose = false)
         {
             string locale = this.GetLocale();
-            return this.InvalidateCache((contentManager, assetName, type) =>
+            return this.InvalidateCache((contentManager, rawName, type) =>
             {
+                IAssetName assetName = this.ParseAssetName(rawName);
                 IAssetInfo info = new AssetInfo(locale, assetName, type, this.MainContentManager.AssertAndNormalizeAssetName);
                 return predicate(info);
             }, dispose);
@@ -320,10 +331,10 @@ namespace StardewModdingAPI.Framework
         /// <param name="predicate">Matches the asset keys to invalidate.</param>
         /// <param name="dispose">Whether to dispose invalidated assets. This should only be <c>true</c> when they're being invalidated as part of a dispose, to avoid crashing the game.</param>
         /// <returns>Returns the invalidated asset names.</returns>
-        public IEnumerable<string> InvalidateCache(Func<IContentManager, string, Type, bool> predicate, bool dispose = false)
+        public IEnumerable<IAssetName> InvalidateCache(Func<IContentManager, string, Type, bool> predicate, bool dispose = false)
         {
             // invalidate cache & track removed assets
-            IDictionary<string, Type> removedAssets = new Dictionary<string, Type>(StringComparer.OrdinalIgnoreCase);
+            IDictionary<IAssetName, Type> removedAssets = new Dictionary<IAssetName, Type>();
             this.ContentManagerLock.InReadLock(() =>
             {
                 // cached assets
@@ -331,8 +342,9 @@ namespace StardewModdingAPI.Framework
                 {
                     foreach (var entry in contentManager.InvalidateCache((key, type) => predicate(contentManager, key, type), dispose))
                     {
-                        if (!removedAssets.ContainsKey(entry.Key))
-                            removedAssets[entry.Key] = entry.Value.GetType();
+                        AssetName assetName = this.ParseAssetName(entry.Key);
+                        if (!removedAssets.ContainsKey(assetName))
+                            removedAssets[assetName] = entry.Value.GetType();
                     }
                 }
 
@@ -346,8 +358,8 @@ namespace StardewModdingAPI.Framework
                             continue;
 
                         // get map path
-                        string mapPath = this.MainContentManager.AssertAndNormalizeAssetName(location.mapPath.Value);
-                        if (!removedAssets.ContainsKey(mapPath) && predicate(this.MainContentManager, mapPath, typeof(Map)))
+                        AssetName mapPath = this.ParseAssetName(this.MainContentManager.AssertAndNormalizeAssetName(location.mapPath.Value));
+                        if (!removedAssets.ContainsKey(mapPath) && predicate(this.MainContentManager, mapPath.Name, typeof(Map)))
                             removedAssets[mapPath] = typeof(Map);
                     }
                 }
@@ -360,17 +372,17 @@ namespace StardewModdingAPI.Framework
                 this.CoreAssets.Propagate(
                     assets: removedAssets.ToDictionary(p => p.Key, p => p.Value),
                     ignoreWorld: Context.IsWorldFullyUnloaded,
-                    out IDictionary<string, bool> propagated,
+                    out IDictionary<IAssetName, bool> propagated,
                     out bool updatedNpcWarps
                 );
 
                 // log summary
                 StringBuilder report = new();
                 {
-                    string[] invalidatedKeys = removedAssets.Keys.ToArray();
-                    string[] propagatedKeys = propagated.Where(p => p.Value).Select(p => p.Key).ToArray();
+                    IAssetName[] invalidatedKeys = removedAssets.Keys.ToArray();
+                    IAssetName[] propagatedKeys = propagated.Where(p => p.Value).Select(p => p.Key).ToArray();
 
-                    string FormatKeyList(IEnumerable<string> keys) => string.Join(", ", keys.OrderBy(p => p, StringComparer.OrdinalIgnoreCase));
+                    string FormatKeyList(IEnumerable<IAssetName> keys) => string.Join(", ", keys.Select(p => p.Name).OrderBy(p => p, StringComparer.OrdinalIgnoreCase));
 
                     report.AppendLine($"Invalidated {invalidatedKeys.Length} asset names ({FormatKeyList(invalidatedKeys)}).");
                     report.AppendLine(propagated.Count > 0
@@ -422,15 +434,6 @@ namespace StardewModdingAPI.Framework
             return tilesheets ?? Array.Empty<TilesheetReference>();
         }
 
-        /// <summary>Get the language enum which corresponds to a locale code (e.g. <see cref="LocalizedContentManager.LanguageCode.fr"/> given <c>fr-FR</c>).</summary>
-        /// <param name="locale">The locale code to search. This must exactly match the language; no fallback is performed.</param>
-        /// <param name="language">The matched language enum, if any.</param>
-        /// <returns>Returns whether a valid language was found.</returns>
-        public bool TryGetLanguageEnum(string locale, out LocalizedContentManager.LanguageCode language)
-        {
-            return this.LocaleCodes.Value.TryGetValue(locale, out language);
-        }
-
         /// <summary>Get the locale code which corresponds to a language enum (e.g. <c>fr-FR</c> given <see cref="LocalizedContentManager.LanguageCode.fr"/>).</summary>
         /// <param name="language">The language enum to search.</param>
         public string GetLocaleCode(LocalizedContentManager.LanguageCode language)
diff --git a/src/SMAPI/Framework/ContentManagers/BaseContentManager.cs b/src/SMAPI/Framework/ContentManagers/BaseContentManager.cs
index 5645c0fa..be892b33 100644
--- a/src/SMAPI/Framework/ContentManagers/BaseContentManager.cs
+++ b/src/SMAPI/Framework/ContentManagers/BaseContentManager.cs
@@ -160,14 +160,6 @@ namespace StardewModdingAPI.Framework.ContentManagers
             return this.IsNormalizedKeyLoaded(assetName, language);
         }
 
-        /// <inheritdoc />
-        public IEnumerable<string> GetAssetKeys()
-        {
-            return this.Cache.Keys
-                .Select(this.GetAssetName)
-                .Distinct();
-        }
-
         /****
         ** Cache invalidation
         ****/
@@ -177,13 +169,13 @@ namespace StardewModdingAPI.Framework.ContentManagers
             IDictionary<string, object> removeAssets = new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase);
             this.Cache.Remove((key, asset) =>
             {
-                this.ParseCacheKey(key, out string assetName, out _);
+                string baseAssetName = this.Coordinator.ParseAssetName(key).BaseName;
 
                 // check if asset should be removed
-                bool remove = removeAssets.ContainsKey(assetName);
-                if (!remove && predicate(assetName, asset.GetType()))
+                bool remove = removeAssets.ContainsKey(baseAssetName);
+                if (!remove && predicate(baseAssetName, asset.GetType()))
                 {
-                    removeAssets[assetName] = asset;
+                    removeAssets[baseAssetName] = asset;
                     remove = true;
                 }
 
@@ -275,44 +267,9 @@ namespace StardewModdingAPI.Framework.ContentManagers
             this.BaseDisposableReferences.Clear();
         }
 
-        /// <summary>Parse a cache key into its component parts.</summary>
-        /// <param name="cacheKey">The input cache key.</param>
-        /// <param name="assetName">The original asset name.</param>
-        /// <param name="localeCode">The asset locale code (or <c>null</c> if not localized).</param>
-        protected void ParseCacheKey(string cacheKey, out string assetName, out string localeCode)
-        {
-            // handle localized key
-            if (!string.IsNullOrWhiteSpace(cacheKey))
-            {
-                int lastSepIndex = cacheKey.LastIndexOf(".", StringComparison.Ordinal);
-                if (lastSepIndex >= 0)
-                {
-                    string suffix = cacheKey.Substring(lastSepIndex + 1, cacheKey.Length - lastSepIndex - 1);
-                    if (this.Coordinator.TryGetLanguageEnum(suffix, out _))
-                    {
-                        assetName = cacheKey.Substring(0, lastSepIndex);
-                        localeCode = cacheKey.Substring(lastSepIndex + 1, cacheKey.Length - lastSepIndex - 1);
-                        return;
-                    }
-                }
-            }
-
-            // handle simple key
-            assetName = cacheKey;
-            localeCode = null;
-        }
-
         /// <summary>Get whether an asset has already been loaded.</summary>
         /// <param name="normalizedAssetName">The normalized asset name.</param>
         /// <param name="language">The language to check.</param>
         protected abstract bool IsNormalizedKeyLoaded(string normalizedAssetName, LanguageCode language);
-
-        /// <summary>Get the asset name from a cache key.</summary>
-        /// <param name="cacheKey">The input cache key.</param>
-        private string GetAssetName(string cacheKey)
-        {
-            this.ParseCacheKey(cacheKey, out string assetName, out string _);
-            return assetName;
-        }
     }
 }
diff --git a/src/SMAPI/Framework/ContentManagers/GameContentManager.cs b/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
index ab198076..0ca9e277 100644
--- a/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
+++ b/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
@@ -73,46 +73,46 @@ namespace StardewModdingAPI.Framework.ContentManagers
             }
 
             // normalize asset name
-            assetName = this.AssertAndNormalizeAssetName(assetName);
-            if (this.TryParseExplicitLanguageAssetKey(assetName, out string newAssetName, out LanguageCode newLanguage))
-                return this.Load<T>(newAssetName, newLanguage, useCache);
+            IAssetName parsedName = this.Coordinator.ParseAssetName(assetName);
+            if (parsedName.LanguageCode.HasValue)
+                return this.Load<T>(parsedName.BaseName, parsedName.LanguageCode.Value, useCache);
 
             // get from cache
-            if (useCache && this.IsLoaded(assetName, language))
-                return this.RawLoad<T>(assetName, language, useCache: true);
+            if (useCache && this.IsLoaded(parsedName.Name, language))
+                return this.RawLoad<T>(parsedName.Name, language, useCache: true);
 
             // get managed asset
-            if (this.Coordinator.TryParseManagedAssetKey(assetName, out string contentManagerID, out string relativePath))
+            if (this.Coordinator.TryParseManagedAssetKey(parsedName.Name, out string contentManagerID, out string relativePath))
             {
                 T managedAsset = this.Coordinator.LoadManagedAsset<T>(contentManagerID, relativePath);
-                this.TrackAsset(assetName, managedAsset, language, useCache);
+                this.TrackAsset(parsedName.Name, managedAsset, language, useCache);
                 return managedAsset;
             }
 
             // load asset
             T data;
-            if (this.AssetsBeingLoaded.Contains(assetName))
+            if (this.AssetsBeingLoaded.Contains(parsedName.Name))
             {
-                this.Monitor.Log($"Broke loop while loading asset '{assetName}'.", LogLevel.Warn);
+                this.Monitor.Log($"Broke loop while loading asset '{parsedName.Name}'.", LogLevel.Warn);
                 this.Monitor.Log($"Bypassing mod loaders for this asset. Stack trace:\n{Environment.StackTrace}");
-                data = this.RawLoad<T>(assetName, language, useCache);
+                data = this.RawLoad<T>(parsedName.Name, language, useCache);
             }
             else
             {
-                data = this.AssetsBeingLoaded.Track(assetName, () =>
+                data = this.AssetsBeingLoaded.Track(parsedName.Name, () =>
                 {
                     string locale = this.GetLocale(language);
-                    IAssetInfo info = new AssetInfo(locale, assetName, typeof(T), this.AssertAndNormalizeAssetName);
+                    IAssetInfo info = new AssetInfo(locale, parsedName, typeof(T), this.AssertAndNormalizeAssetName);
                     IAssetData asset =
                         this.ApplyLoader<T>(info)
-                        ?? new AssetDataForObject(info, this.RawLoad<T>(assetName, language, useCache), this.AssertAndNormalizeAssetName);
+                        ?? new AssetDataForObject(info, this.RawLoad<T>(parsedName.Name, language, useCache), this.AssertAndNormalizeAssetName);
                     asset = this.ApplyEditors<T>(info, asset);
                     return (T)asset.Data;
                 });
             }
 
             // update cache & return data
-            this.TrackAsset(assetName, data, language, useCache);
+            this.TrackAsset(parsedName.Name, data, language, useCache);
             return data;
         }
 
@@ -124,13 +124,16 @@ namespace StardewModdingAPI.Framework.ContentManagers
             // find assets for which a translatable version was loaded
             HashSet<string> removeAssetNames = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
             foreach (string key in this.LocalizedAssetNames.Where(p => p.Key != p.Value).Select(p => p.Key))
-                removeAssetNames.Add(this.TryParseExplicitLanguageAssetKey(key, out string assetName, out _) ? assetName : key);
+            {
+                IAssetName assetName = this.Coordinator.ParseAssetName(key);
+                removeAssetNames.Add(assetName.BaseName);
+            }
 
             // invalidate translatable assets
             string[] invalidated = this
                 .InvalidateCache((key, type) =>
                     removeAssetNames.Contains(key)
-                    || (this.TryParseExplicitLanguageAssetKey(key, out string assetName, out _) && removeAssetNames.Contains(assetName))
+                    || removeAssetNames.Contains(this.Coordinator.ParseAssetName(key).BaseName)
                 )
                 .Select(p => p.Key)
                 .OrderBy(p => p, StringComparer.OrdinalIgnoreCase)
@@ -168,9 +171,10 @@ namespace StardewModdingAPI.Framework.ContentManagers
         {
             // handle explicit language in asset name
             {
-                if (this.TryParseExplicitLanguageAssetKey(assetName, out string newAssetName, out LanguageCode newLanguage))
+                IAssetName parsedName = this.Coordinator.ParseAssetName(assetName);
+                if (parsedName.LanguageCode.HasValue)
                 {
-                    this.TrackAsset(newAssetName, value, newLanguage, useCache);
+                    this.TrackAsset(parsedName.BaseName, value, parsedName.LanguageCode.Value, useCache);
                     return;
                 }
             }
@@ -238,30 +242,6 @@ namespace StardewModdingAPI.Framework.ContentManagers
             }
         }
 
-        /// <summary>Parse an asset key that contains an explicit language into its asset name and language, if applicable.</summary>
-        /// <param name="rawAsset">The asset key to parse.</param>
-        /// <param name="assetName">The asset name without the language code.</param>
-        /// <param name="language">The language code removed from the asset name.</param>
-        /// <returns>Returns whether the asset key contains an explicit language and was successfully parsed.</returns>
-        private bool TryParseExplicitLanguageAssetKey(string rawAsset, out string assetName, out LanguageCode language)
-        {
-            if (string.IsNullOrWhiteSpace(rawAsset))
-                throw new SContentLoadException("The asset key is empty.");
-
-            // extract language code
-            int splitIndex = rawAsset.LastIndexOf('.');
-            if (splitIndex != -1 && this.Coordinator.TryGetLanguageEnum(rawAsset.Substring(splitIndex + 1), out language))
-            {
-                assetName = rawAsset.Substring(0, splitIndex);
-                return true;
-            }
-
-            // no explicit language code found
-            assetName = rawAsset;
-            language = this.Language;
-            return false;
-        }
-
         /// <summary>Load the initial asset from the registered <see cref="Loaders"/>.</summary>
         /// <param name="info">The basic asset metadata.</param>
         /// <returns>Returns the loaded asset metadata, or <c>null</c> if no loader matched.</returns>
@@ -277,7 +257,7 @@ namespace StardewModdingAPI.Framework.ContentManagers
                     }
                     catch (Exception ex)
                     {
-                        entry.Mod.LogAsMod($"Mod failed when checking whether it could load asset '{info.AssetName}', and will be ignored. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
+                        entry.Mod.LogAsMod($"Mod failed when checking whether it could load asset '{info.Name}', and will be ignored. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
                         return false;
                     }
                 })
@@ -289,7 +269,7 @@ namespace StardewModdingAPI.Framework.ContentManagers
             if (loaders.Length > 1)
             {
                 string[] loaderNames = loaders.Select(p => p.Mod.DisplayName).ToArray();
-                this.Monitor.Log($"Multiple mods want to provide the '{info.AssetName}' asset ({string.Join(", ", loaderNames)}), but an asset can't be loaded multiple times. SMAPI will use the default asset instead; uninstall one of the mods to fix this. (Message for modders: you should usually use {typeof(IAssetEditor)} instead to avoid conflicts.)", LogLevel.Warn);
+                this.Monitor.Log($"Multiple mods want to provide the '{info.Name}' asset ({string.Join(", ", loaderNames)}), but an asset can't be loaded multiple times. SMAPI will use the default asset instead; uninstall one of the mods to fix this. (Message for modders: you should usually use {typeof(IAssetEditor)} instead to avoid conflicts.)", LogLevel.Warn);
                 return null;
             }
 
@@ -300,11 +280,11 @@ namespace StardewModdingAPI.Framework.ContentManagers
             try
             {
                 data = loader.Load<T>(info);
-                this.Monitor.Log($"{mod.DisplayName} loaded asset '{info.AssetName}'.", LogLevel.Trace);
+                this.Monitor.Log($"{mod.DisplayName} loaded asset '{info.Name}'.", LogLevel.Trace);
             }
             catch (Exception ex)
             {
-                mod.LogAsMod($"Mod crashed when loading asset '{info.AssetName}'. SMAPI will use the default asset instead. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
+                mod.LogAsMod($"Mod crashed when loading asset '{info.Name}'. SMAPI will use the default asset instead. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
                 return null;
             }
 
@@ -349,7 +329,7 @@ namespace StardewModdingAPI.Framework.ContentManagers
                 }
                 catch (Exception ex)
                 {
-                    mod.LogAsMod($"Mod crashed when checking whether it could edit asset '{info.AssetName}', and will be ignored. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
+                    mod.LogAsMod($"Mod crashed when checking whether it could edit asset '{info.Name}', and will be ignored. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
                     continue;
                 }
 
@@ -358,22 +338,22 @@ namespace StardewModdingAPI.Framework.ContentManagers
                 try
                 {
                     editor.Edit<T>(asset);
-                    this.Monitor.Log($"{mod.DisplayName} edited {info.AssetName}.");
+                    this.Monitor.Log($"{mod.DisplayName} edited {info.Name}.");
                 }
                 catch (Exception ex)
                 {
-                    mod.LogAsMod($"Mod crashed when editing asset '{info.AssetName}', which may cause errors in-game. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
+                    mod.LogAsMod($"Mod crashed when editing asset '{info.Name}', which may cause errors in-game. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
                 }
 
                 // validate edit
                 if (asset.Data == null)
                 {
-                    mod.LogAsMod($"Mod incorrectly set asset '{info.AssetName}' to a null value; ignoring override.", LogLevel.Warn);
+                    mod.LogAsMod($"Mod incorrectly set asset '{info.Name}' to a null value; ignoring override.", LogLevel.Warn);
                     asset = GetNewData(prevAsset);
                 }
                 else if (!(asset.Data is T))
                 {
-                    mod.LogAsMod($"Mod incorrectly set asset '{asset.AssetName}' to incompatible type '{asset.Data.GetType()}', expected '{typeof(T)}'; ignoring override.", LogLevel.Warn);
+                    mod.LogAsMod($"Mod incorrectly set asset '{asset.Name}' to incompatible type '{asset.Data.GetType()}', expected '{typeof(T)}'; ignoring override.", LogLevel.Warn);
                     asset = GetNewData(prevAsset);
                 }
             }
@@ -393,21 +373,21 @@ namespace StardewModdingAPI.Framework.ContentManagers
             // can't load a null asset
             if (data == null)
             {
-                mod.LogAsMod($"SMAPI blocked asset replacement for '{info.AssetName}': mod incorrectly set asset to a null value.", LogLevel.Error);
+                mod.LogAsMod($"SMAPI blocked asset replacement for '{info.Name}': mod incorrectly set asset to a null value.", LogLevel.Error);
                 return false;
             }
 
             // when replacing a map, the vanilla tilesheets must have the same order and IDs
             if (data is Map loadedMap)
             {
-                TilesheetReference[] vanillaTilesheetRefs = this.Coordinator.GetVanillaTilesheetIds(info.AssetName);
+                TilesheetReference[] vanillaTilesheetRefs = this.Coordinator.GetVanillaTilesheetIds(info.Name.Name);
                 foreach (TilesheetReference vanillaSheet in vanillaTilesheetRefs)
                 {
                     // add missing tilesheet
                     if (loadedMap.GetTileSheet(vanillaSheet.Id) == null)
                     {
                         mod.Monitor.LogOnce("SMAPI fixed maps loaded by this mod to prevent errors. See the log file for details.", LogLevel.Warn);
-                        this.Monitor.Log($"Fixed broken map replacement: {mod.DisplayName} loaded '{info.AssetName}' without a required tilesheet (id: {vanillaSheet.Id}, source: {vanillaSheet.ImageSource}).");
+                        this.Monitor.Log($"Fixed broken map replacement: {mod.DisplayName} loaded '{info.Name}' without a required tilesheet (id: {vanillaSheet.Id}, source: {vanillaSheet.ImageSource}).");
 
                         loadedMap.AddTileSheet(new TileSheet(vanillaSheet.Id, loadedMap, vanillaSheet.ImageSource, vanillaSheet.SheetSize, vanillaSheet.TileSize));
                     }
@@ -417,17 +397,17 @@ namespace StardewModdingAPI.Framework.ContentManagers
                     {
                         // only show warning if not farm map
                         // This is temporary: mods shouldn't do this for any vanilla map, but these are the ones we know will crash. Showing a warning for others instead gives modders time to update their mods, while still simplifying troubleshooting.
-                        bool isFarmMap = info.AssetNameEquals("Maps/Farm") || info.AssetNameEquals("Maps/Farm_Combat") || info.AssetNameEquals("Maps/Farm_Fishing") || info.AssetNameEquals("Maps/Farm_Foraging") || info.AssetNameEquals("Maps/Farm_FourCorners") || info.AssetNameEquals("Maps/Farm_Island") || info.AssetNameEquals("Maps/Farm_Mining");
+                        bool isFarmMap = info.Name.IsEquivalentTo("Maps/Farm") || info.Name.IsEquivalentTo("Maps/Farm_Combat") || info.Name.IsEquivalentTo("Maps/Farm_Fishing") || info.Name.IsEquivalentTo("Maps/Farm_Foraging") || info.Name.IsEquivalentTo("Maps/Farm_FourCorners") || info.Name.IsEquivalentTo("Maps/Farm_Island") || info.Name.IsEquivalentTo("Maps/Farm_Mining");
 
                         string reason = $"mod reordered the original tilesheets, which {(isFarmMap ? "would cause a crash" : "often causes crashes")}.\nTechnical details for mod author: Expected order: {string.Join(", ", vanillaTilesheetRefs.Select(p => p.Id))}. See https://stardewvalleywiki.com/Modding:Maps#Tilesheet_order for help.";
 
                         SCore.DeprecationManager.PlaceholderWarn("3.8.2", DeprecationLevel.PendingRemoval);
                         if (isFarmMap)
                         {
-                            mod.LogAsMod($"SMAPI blocked '{info.AssetName}' map load: {reason}", LogLevel.Error);
+                            mod.LogAsMod($"SMAPI blocked '{info.Name}' map load: {reason}", LogLevel.Error);
                             return false;
                         }
-                        mod.LogAsMod($"SMAPI found an issue with '{info.AssetName}' map load: {reason}", LogLevel.Warn);
+                        mod.LogAsMod($"SMAPI found an issue with '{info.Name}' map load: {reason}", LogLevel.Warn);
                     }
                 }
             }
diff --git a/src/SMAPI/Framework/ContentManagers/IContentManager.cs b/src/SMAPI/Framework/ContentManagers/IContentManager.cs
index d7963305..ba7dbc06 100644
--- a/src/SMAPI/Framework/ContentManagers/IContentManager.cs
+++ b/src/SMAPI/Framework/ContentManagers/IContentManager.cs
@@ -58,9 +58,6 @@ namespace StardewModdingAPI.Framework.ContentManagers
         /// <param name="language">The language.</param>
         bool IsLoaded(string assetName, LocalizedContentManager.LanguageCode language);
 
-        /// <summary>Get the cached asset keys.</summary>
-        IEnumerable<string> GetAssetKeys();
-
         /// <summary>Purge matched assets from the cache.</summary>
         /// <param name="predicate">Matches the asset keys to invalidate.</param>
         /// <param name="dispose">Whether to dispose invalidated assets. This should only be <c>true</c> when they're being invalidated as part of a dispose, to avoid crashing the game.</param>
diff --git a/src/SMAPI/Framework/ContentManagers/ModContentManager.cs b/src/SMAPI/Framework/ContentManagers/ModContentManager.cs
index beb90a5d..21f88d47 100644
--- a/src/SMAPI/Framework/ContentManagers/ModContentManager.cs
+++ b/src/SMAPI/Framework/ContentManagers/ModContentManager.cs
@@ -80,7 +80,7 @@ namespace StardewModdingAPI.Framework.ContentManagers
         {
             // normalize key
             bool isXnbFile = Path.GetExtension(assetName).ToLower() == ".xnb";
-            assetName = this.AssertAndNormalizeAssetName(assetName);
+            IAssetName parsedName = this.Coordinator.ParseAssetName(assetName);
 
             // disable caching
             // This is necessary to avoid assets being shared between content managers, which can
@@ -97,21 +97,21 @@ namespace StardewModdingAPI.Framework.ContentManagers
 
             // resolve managed asset key
             {
-                if (this.Coordinator.TryParseManagedAssetKey(assetName, out string contentManagerID, out string relativePath))
+                if (this.Coordinator.TryParseManagedAssetKey(parsedName.Name, out string contentManagerID, out string relativePath))
                 {
                     if (contentManagerID != this.Name)
-                        throw new SContentLoadException($"Can't load managed asset key '{assetName}' through content manager '{this.Name}' for a different mod.");
-                    assetName = relativePath;
+                        throw new SContentLoadException($"Can't load managed asset key '{parsedName}' through content manager '{this.Name}' for a different mod.");
+                    parsedName = this.Coordinator.ParseAssetName(relativePath);
                 }
             }
 
             // get local asset
-            SContentLoadException GetContentError(string reasonPhrase) => new SContentLoadException($"Failed loading asset '{assetName}' from {this.Name}: {reasonPhrase}");
+            SContentLoadException GetContentError(string reasonPhrase) => new SContentLoadException($"Failed loading asset '{parsedName}' from {this.Name}: {reasonPhrase}");
             T asset;
             try
             {
                 // get file
-                FileInfo file = this.GetModFile(isXnbFile ? $"{assetName}.xnb" : assetName); // .xnb extension is stripped from asset names passed to the content manager
+                FileInfo file = this.GetModFile(isXnbFile ? $"{parsedName}.xnb" : parsedName.Name); // .xnb extension is stripped from asset names passed to the content manager
                 if (!file.Exists)
                     throw GetContentError("the specified path doesn't exist.");
 
@@ -121,11 +121,11 @@ namespace StardewModdingAPI.Framework.ContentManagers
                     // XNB file
                     case ".xnb":
                         {
-                            asset = this.RawLoad<T>(assetName, useCache: false);
+                            asset = this.RawLoad<T>(parsedName.Name, useCache: false);
                             if (asset is Map map)
                             {
-                                map.assetPath = assetName;
-                                this.FixTilesheetPaths(map, relativeMapPath: assetName, fixEagerPathPrefixes: true);
+                                map.assetPath = parsedName.Name;
+                                this.FixTilesheetPaths(map, relativeMapPath: parsedName.Name, fixEagerPathPrefixes: true);
                             }
                         }
                         break;
@@ -173,8 +173,8 @@ namespace StardewModdingAPI.Framework.ContentManagers
                             // fetch & cache
                             FormatManager formatManager = FormatManager.Instance;
                             Map map = formatManager.LoadMap(file.FullName);
-                            map.assetPath = assetName;
-                            this.FixTilesheetPaths(map, relativeMapPath: assetName, fixEagerPathPrefixes: false);
+                            map.assetPath = parsedName.Name;
+                            this.FixTilesheetPaths(map, relativeMapPath: parsedName.Name, fixEagerPathPrefixes: false);
                             asset = (T)(object)map;
                         }
                         break;
@@ -185,11 +185,11 @@ namespace StardewModdingAPI.Framework.ContentManagers
             }
             catch (Exception ex) when (!(ex is SContentLoadException))
             {
-                throw new SContentLoadException($"The content manager failed loading content asset '{assetName}' from {this.Name}.", ex);
+                throw new SContentLoadException($"The content manager failed loading content asset '{parsedName}' from {this.Name}.", ex);
             }
 
             // track & return asset
-            this.TrackAsset(assetName, asset, language, useCache);
+            this.TrackAsset(parsedName.Name, asset, language, useCache);
             return asset;
         }
 
diff --git a/src/SMAPI/Framework/ModHelpers/ContentHelper.cs b/src/SMAPI/Framework/ModHelpers/ContentHelper.cs
index bfca2264..a01248a8 100644
--- a/src/SMAPI/Framework/ModHelpers/ContentHelper.cs
+++ b/src/SMAPI/Framework/ModHelpers/ContentHelper.cs
@@ -129,7 +129,7 @@ namespace StardewModdingAPI.Framework.ModHelpers
         {
             string actualKey = this.GetActualAssetKey(key, ContentSource.GameContent);
             this.Monitor.Log($"Requested cache invalidation for '{actualKey}'.", LogLevel.Trace);
-            return this.ContentCore.InvalidateCache(asset => asset.AssetNameEquals(actualKey)).Any();
+            return this.ContentCore.InvalidateCache(asset => asset.Name.IsEquivalentTo(actualKey)).Any();
         }
 
         /// <inheritdoc />
@@ -153,7 +153,8 @@ namespace StardewModdingAPI.Framework.ModHelpers
                 throw new ArgumentNullException(nameof(data), "Can't get a patch helper for a null value.");
 
             assetName ??= $"temp/{Guid.NewGuid():N}";
-            return new AssetDataForObject(this.CurrentLocale, assetName, data, this.NormalizeAssetName);
+
+            return new AssetDataForObject(this.CurrentLocale, this.ContentCore.ParseAssetName(assetName), data, this.NormalizeAssetName);
         }
 
 
diff --git a/src/SMAPI/IAssetInfo.cs b/src/SMAPI/IAssetInfo.cs
index 6cdf01ee..6ac8358d 100644
--- a/src/SMAPI/IAssetInfo.cs
+++ b/src/SMAPI/IAssetInfo.cs
@@ -11,7 +11,11 @@ namespace StardewModdingAPI
         /// <summary>The content's locale code, if the content is localized.</summary>
         string Locale { get; }
 
+        /// <summary>The asset name being read.</summary>
+        public IAssetName Name { get; }
+
         /// <summary>The normalized asset name being read. The format may change between platforms; see <see cref="AssetNameEquals"/> to compare with a known path.</summary>
+        [Obsolete($"Use {nameof(Name)} instead.")]
         string AssetName { get; }
 
         /// <summary>The content data type.</summary>
@@ -23,6 +27,7 @@ namespace StardewModdingAPI
         *********/
         /// <summary>Get whether the asset name being loaded matches a given name after normalization.</summary>
         /// <param name="path">The expected asset path, relative to the game's content folder and without the .xnb extension or locale suffix (like 'Data\ObjectInformation').</param>
+        [Obsolete($"Use {nameof(Name)}.{nameof(IAssetName.IsEquivalentTo)} instead.")]
         bool AssetNameEquals(string path);
     }
 }
diff --git a/src/SMAPI/IAssetName.cs b/src/SMAPI/IAssetName.cs
new file mode 100644
index 00000000..a5bfea93
--- /dev/null
+++ b/src/SMAPI/IAssetName.cs
@@ -0,0 +1,44 @@
+using System;
+using StardewValley;
+
+namespace StardewModdingAPI
+{
+    /// <summary>The name for an asset loaded through the content pipeline.</summary>
+    public interface IAssetName : IEquatable<IAssetName>
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The full normalized asset name, including the locale if applicable (like <c>Data/Achievements.fr-FR</c>).</summary>
+        string Name { get; }
+
+        /// <summary>The base asset name without the locale code.</summary>
+        string BaseName { get; }
+
+        /// <summary>The locale code specified in the <see cref="Name"/>, if it's a valid code recognized by the game content.</summary>
+        string LocaleCode { get; }
+
+        /// <summary>The language code matching the <see cref="LocaleCode"/>, if applicable.</summary>
+        LocalizedContentManager.LanguageCode? LanguageCode { get; }
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Get whether the given asset name is equivalent, ignoring capitalization and formatting.</summary>
+        /// <param name="assetName">The asset name to compare this instance to.</param>
+        /// <param name="useBaseName">Whether to compare the given name with the <see cref="BaseName"/> (if true) or <see cref="Name"/> (if false). This has no effect on any locale included in the given <paramref name="assetName"/>.</param>
+        bool IsEquivalentTo(string assetName, bool useBaseName = false);
+
+        /// <summary>Get whether the asset name starts with the given value, ignoring capitalization and formatting. This can be used with a trailing slash to test for an asset folder, like <c>Data/</c>.</summary>
+        /// <param name="prefix">The prefix to match.</param>
+        /// <param name="allowPartialWord">Whether to match if the prefix occurs mid-word, so <c>Data/AchievementsToIgnore</c> matches prefix <c>Data/Achievements</c>. If this is false, the prefix only matches if the asset name starts with the prefix followed by a non-alphanumeric character (including <c>.</c>, <c>/</c>, or <c>\\</c>) or the end of string.</param>
+        /// <param name="allowSubfolder">Whether to match the prefix if there's a subfolder path after it, so <c>Data/Achievements/Example</c> matches prefix <c>Data/Achievements</c>. If this is false, the prefix only matches if the asset name has no <c>/</c> or <c>\\</c> characters after the prefix.</param>
+        bool StartsWith(string prefix, bool allowPartialWord = true, bool allowSubfolder = true);
+
+        /// <summary>Get whether the asset is directly within the given asset path.</summary>
+        /// <remarks>For example, <c>Characters/Dialogue/Abigail</c> is directly under <c>Characters/Dialogue</c> but not <c>Characters</c> or <c>Characters/Dialogue/Ab</c>. To allow sub-paths, use <see cref="StartsWith"/> instead.</remarks>
+        /// <param name="assetFolder">The asset path to check. This doesn't need a trailing slash.</param>
+        bool IsDirectlyUnderPath(string assetFolder);
+    }
+}
diff --git a/src/SMAPI/Metadata/CoreAssetPropagator.cs b/src/SMAPI/Metadata/CoreAssetPropagator.cs
index a6c4bb24..e7fac578 100644
--- a/src/SMAPI/Metadata/CoreAssetPropagator.cs
+++ b/src/SMAPI/Metadata/CoreAssetPropagator.cs
@@ -87,22 +87,22 @@ namespace StardewModdingAPI.Metadata
         /// <param name="ignoreWorld">Whether the in-game world is fully unloaded (e.g. on the title screen), so there's no need to propagate changes into the world.</param>
         /// <param name="propagatedAssets">A lookup of asset names to whether they've been propagated.</param>
         /// <param name="updatedNpcWarps">Whether the NPC pathfinding cache was reloaded.</param>
-        public void Propagate(IDictionary<string, Type> assets, bool ignoreWorld, out IDictionary<string, bool> propagatedAssets, out bool updatedNpcWarps)
+        public void Propagate(IDictionary<IAssetName, Type> assets, bool ignoreWorld, out IDictionary<IAssetName, bool> propagatedAssets, out bool updatedNpcWarps)
         {
             // group into optimized lists
             var buckets = assets.GroupBy(p =>
             {
-                if (this.IsInFolder(p.Key, "Characters") || this.IsInFolder(p.Key, "Characters/Monsters"))
+                if (p.Key.IsDirectlyUnderPath("Characters") || p.Key.IsDirectlyUnderPath("Characters/Monsters"))
                     return AssetBucket.Sprite;
 
-                if (this.IsInFolder(p.Key, "Portraits"))
+                if (p.Key.IsDirectlyUnderPath("Portraits"))
                     return AssetBucket.Portrait;
 
                 return AssetBucket.Other;
             });
 
             // reload assets
-            propagatedAssets = assets.ToDictionary(p => p.Key, _ => false, StringComparer.OrdinalIgnoreCase);
+            propagatedAssets = assets.ToDictionary(p => p.Key, _ => false);
             updatedNpcWarps = false;
             foreach (var bucket in buckets)
             {
@@ -149,16 +149,16 @@ namespace StardewModdingAPI.Metadata
         ** Private methods
         *********/
         /// <summary>Reload one of the game's core assets (if applicable).</summary>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <param name="type">The asset type to reload.</param>
         /// <param name="ignoreWorld">Whether the in-game world is fully unloaded (e.g. on the title screen), so there's no need to propagate changes into the world.</param>
         /// <param name="changedWarps">Whether any map warps were changed as part of this propagation.</param>
         /// <returns>Returns whether an asset was loaded. The return value may be true or false, or a non-null value for true.</returns>
         [SuppressMessage("ReSharper", "StringLiteralTypo", Justification = "These deliberately match the asset names.")]
-        private bool PropagateOther(string key, Type type, bool ignoreWorld, out bool changedWarps)
+        private bool PropagateOther(IAssetName assetName, Type type, bool ignoreWorld, out bool changedWarps)
         {
             var content = this.MainContentManager;
-            key = this.AssertAndNormalizeAssetName(key);
+            string key = assetName.Name;
             changedWarps = false;
 
             /****
@@ -170,7 +170,7 @@ namespace StardewModdingAPI.Metadata
             {
                 foreach (TileSheet tilesheet in Game1.currentLocation.map.TileSheets)
                 {
-                    if (this.IsSameAssetKey(tilesheet.ImageSource, key))
+                    if (assetName.IsEquivalentTo(tilesheet.ImageSource))
                         Game1.mapDisplayDevice.LoadTileSheet(tilesheet);
                 }
             }
@@ -188,7 +188,7 @@ namespace StardewModdingAPI.Metadata
                     {
                         GameLocation location = info.Location;
 
-                        if (this.IsSameAssetKey(location.mapPath.Value, key))
+                        if (assetName.IsEquivalentTo(location.mapPath.Value))
                         {
                             static ISet<string> GetWarpSet(GameLocation location)
                             {
@@ -213,14 +213,13 @@ namespace StardewModdingAPI.Metadata
             /****
             ** Propagate by key
             ****/
-            Reflector reflection = this.Reflection;
-            switch (key.ToLower().Replace("\\", "/")) // normalized key so we can compare statically
+            switch (assetName.Name.ToLower().Replace("\\", "/")) // normalized key so we can compare statically
             {
                 /****
                 ** Animals
                 ****/
                 case "animals/horse":
-                    return !ignoreWorld && this.ReloadPetOrHorseSprites<Horse>(content, key);
+                    return !ignoreWorld && this.ReloadPetOrHorseSprites<Horse>(content, assetName);
 
                 /****
                 ** Buildings
@@ -231,7 +230,7 @@ namespace StardewModdingAPI.Metadata
 
                 case "buildings/houses_paintmask": // Farm
                     {
-                        bool removedFromCache = this.RemoveFromPaintMaskCache(key);
+                        bool removedFromCache = this.RemoveFromPaintMaskCache(assetName);
 
                         Farm farm = Game1.getFarm();
                         farm?.ApplyHousePaint();
@@ -250,7 +249,7 @@ namespace StardewModdingAPI.Metadata
                 case "characters/farmer/farmer_base_bald":
                 case "characters/farmer/farmer_girl_base":
                 case "characters/farmer/farmer_girl_base_bald":
-                    return !ignoreWorld && this.ReloadPlayerSprites(key);
+                    return !ignoreWorld && this.ReloadPlayerSprites(assetName);
 
                 case "characters/farmer/hairstyles": // Game1.LoadContent
                     FarmerRenderer.hairStylesTexture = this.LoadAndDisposeIfNeeded(FarmerRenderer.hairStylesTexture, key);
@@ -313,7 +312,7 @@ namespace StardewModdingAPI.Metadata
                     return true;
 
                 case "data/npcdispositions": // NPC constructor
-                    return !ignoreWorld && this.ReloadNpcDispositions(content, key);
+                    return !ignoreWorld && this.ReloadNpcDispositions(content, assetName);
 
                 case "data/npcgifttastes": // Game1.LoadContent
                     Game1.NPCGiftTastes = content.Load<Dictionary<string, string>>(key);
@@ -393,7 +392,7 @@ namespace StardewModdingAPI.Metadata
                     }
 
                     if (!ignoreWorld)
-                        this.ReloadDoorSprites(content, key);
+                        this.ReloadDoorSprites(content, assetName);
                     return true;
 
                 case "loosesprites/cursors2": // Game1.LoadContent
@@ -425,7 +424,7 @@ namespace StardewModdingAPI.Metadata
                     return true;
 
                 case "loosesprites/suspensionbridge": // SuspensionBridge constructor
-                    return !ignoreWorld && this.ReloadSuspensionBridges(content, key);
+                    return !ignoreWorld && this.ReloadSuspensionBridges(content, assetName);
 
                 /****
                 ** Content\Maps
@@ -456,7 +455,7 @@ namespace StardewModdingAPI.Metadata
                     return false;
 
                 case "minigames/titlebuttons": // TitleMenu
-                    return this.ReloadTitleButtons(content, key);
+                    return this.ReloadTitleButtons(content, assetName);
 
                 /****
                 ** Content\Strings
@@ -480,14 +479,14 @@ namespace StardewModdingAPI.Metadata
                     return true;
 
                 case "tilesheets/chairtiles": // Game1.LoadContent
-                    return this.ReloadChairTiles(content, key, ignoreWorld);
+                    return this.ReloadChairTiles(content, assetName, ignoreWorld);
 
                 case "tilesheets/craftables": // Game1.LoadContent
                     Game1.bigCraftableSpriteSheet = content.Load<Texture2D>(key);
                     return true;
 
                 case "tilesheets/critters": // Critter constructor
-                    return !ignoreWorld && this.ReloadCritterTextures(content, key) > 0;
+                    return !ignoreWorld && this.ReloadCritterTextures(content, assetName) > 0;
 
                 case "tilesheets/crops": // Game1.LoadContent
                     Game1.cropSpriteSheet = content.Load<Texture2D>(key);
@@ -541,7 +540,7 @@ namespace StardewModdingAPI.Metadata
                     return true;
 
                 case "terrainfeatures/grass": // from Grass
-                    return !ignoreWorld && this.ReloadGrassTextures(content, key);
+                    return !ignoreWorld && this.ReloadGrassTextures(content, assetName);
 
                 case "terrainfeatures/hoedirt": // from HoeDirt
                     HoeDirt.lightTexture = content.Load<Texture2D>(key);
@@ -556,27 +555,27 @@ namespace StardewModdingAPI.Metadata
                     return true;
 
                 case "terrainfeatures/mushroom_tree": // from Tree
-                    return !ignoreWorld && this.ReloadTreeTextures(content, key, Tree.mushroomTree);
+                    return !ignoreWorld && this.ReloadTreeTextures(content, assetName, Tree.mushroomTree);
 
                 case "terrainfeatures/tree_palm": // from Tree
-                    return !ignoreWorld && this.ReloadTreeTextures(content, key, Tree.palmTree);
+                    return !ignoreWorld && this.ReloadTreeTextures(content, assetName, Tree.palmTree);
 
                 case "terrainfeatures/tree1_fall": // from Tree
                 case "terrainfeatures/tree1_spring": // from Tree
                 case "terrainfeatures/tree1_summer": // from Tree
                 case "terrainfeatures/tree1_winter": // from Tree
-                    return !ignoreWorld && this.ReloadTreeTextures(content, key, Tree.bushyTree);
+                    return !ignoreWorld && this.ReloadTreeTextures(content, assetName, Tree.bushyTree);
 
                 case "terrainfeatures/tree2_fall": // from Tree
                 case "terrainfeatures/tree2_spring": // from Tree
                 case "terrainfeatures/tree2_summer": // from Tree
                 case "terrainfeatures/tree2_winter": // from Tree
-                    return !ignoreWorld && this.ReloadTreeTextures(content, key, Tree.leafyTree);
+                    return !ignoreWorld && this.ReloadTreeTextures(content, assetName, Tree.leafyTree);
 
                 case "terrainfeatures/tree3_fall": // from Tree
                 case "terrainfeatures/tree3_spring": // from Tree
                 case "terrainfeatures/tree3_winter": // from Tree
-                    return !ignoreWorld && this.ReloadTreeTextures(content, key, Tree.pineTree);
+                    return !ignoreWorld && this.ReloadTreeTextures(content, assetName, Tree.pineTree);
             }
 
             /****
@@ -585,25 +584,25 @@ namespace StardewModdingAPI.Metadata
             if (!ignoreWorld)
             {
                 // dynamic textures
-                if (this.KeyStartsWith(key, "animals/cat"))
-                    return this.ReloadPetOrHorseSprites<Cat>(content, key);
-                if (this.KeyStartsWith(key, "animals/dog"))
-                    return this.ReloadPetOrHorseSprites<Dog>(content, key);
-                if (this.IsInFolder(key, "Animals"))
-                    return this.ReloadFarmAnimalSprites(content, key);
+                if (assetName.StartsWith("animals/cat"))
+                    return this.ReloadPetOrHorseSprites<Cat>(content, assetName);
+                if (assetName.StartsWith("animals/dog"))
+                    return this.ReloadPetOrHorseSprites<Dog>(content, assetName);
+                if (assetName.IsDirectlyUnderPath("Animals"))
+                    return this.ReloadFarmAnimalSprites(content, assetName);
 
-                if (this.IsInFolder(key, "Buildings"))
-                    return this.ReloadBuildings(key);
+                if (assetName.IsDirectlyUnderPath("Buildings"))
+                    return this.ReloadBuildings(assetName);
 
-                if (this.KeyStartsWith(key, "LooseSprites/Fence"))
-                    return this.ReloadFenceTextures(key);
+                if (assetName.StartsWith("LooseSprites/Fence"))
+                    return this.ReloadFenceTextures(assetName);
 
                 // dynamic data
-                if (this.IsInFolder(key, "Characters/Dialogue"))
-                    return this.ReloadNpcDialogue(key);
+                if (assetName.IsDirectlyUnderPath("Characters/Dialogue"))
+                    return this.ReloadNpcDialogue(assetName);
 
-                if (this.IsInFolder(key, "Characters/schedules"))
-                    return this.ReloadNpcSchedules(key);
+                if (assetName.IsDirectlyUnderPath("Characters/schedules"))
+                    return this.ReloadNpcSchedules(assetName);
             }
 
             return false;
@@ -618,14 +617,14 @@ namespace StardewModdingAPI.Metadata
         ****/
         /// <summary>Reload buttons on the title screen.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
         /// <remarks>Derived from the <see cref="TitleMenu"/> constructor and <see cref="TitleMenu.setUpIcons"/>.</remarks>
-        private bool ReloadTitleButtons(LocalizedContentManager content, string key)
+        private bool ReloadTitleButtons(LocalizedContentManager content, IAssetName assetName)
         {
             if (Game1.activeClickableMenu is TitleMenu titleMenu)
             {
-                Texture2D texture = content.Load<Texture2D>(key);
+                Texture2D texture = content.Load<Texture2D>(assetName.Name);
 
                 titleMenu.titleButtonsTexture = texture;
                 titleMenu.backButton.texture = texture;
@@ -645,21 +644,21 @@ namespace StardewModdingAPI.Metadata
         /// <summary>Reload the sprites for matching pets or horses.</summary>
         /// <typeparam name="TAnimal">The animal type.</typeparam>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
-        private bool ReloadPetOrHorseSprites<TAnimal>(LocalizedContentManager content, string key)
+        private bool ReloadPetOrHorseSprites<TAnimal>(LocalizedContentManager content, IAssetName assetName)
             where TAnimal : NPC
         {
             // find matches
             TAnimal[] animals = this.GetCharacters()
                 .OfType<TAnimal>()
-                .Where(p => this.IsSameAssetKey(p.Sprite?.Texture?.Name, key))
+                .Where(p => assetName.IsEquivalentTo(p.Sprite?.Texture?.Name))
                 .ToArray();
             if (!animals.Any())
                 return false;
 
             // update sprites
-            Texture2D texture = content.Load<Texture2D>(key);
+            Texture2D texture = content.Load<Texture2D>(assetName.Name);
             foreach (TAnimal animal in animals)
                 animal.Sprite.spriteTexture = texture;
             return true;
@@ -667,10 +666,10 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload the sprites for matching farm animals.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
         /// <remarks>Derived from <see cref="FarmAnimal.reload"/>.</remarks>
-        private bool ReloadFarmAnimalSprites(LocalizedContentManager content, string key)
+        private bool ReloadFarmAnimalSprites(LocalizedContentManager content, IAssetName assetName)
         {
             // find matches
             FarmAnimal[] animals = this.GetFarmAnimals().ToArray();
@@ -678,7 +677,7 @@ namespace StardewModdingAPI.Metadata
                 return false;
 
             // update sprites
-            Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(key));
+            Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(assetName.Name));
             foreach (FarmAnimal animal in animals)
             {
                 // get expected key
@@ -690,23 +689,23 @@ namespace StardewModdingAPI.Metadata
                 expectedKey = $"Animals/{expectedKey}";
 
                 // reload asset
-                if (this.IsSameAssetKey(expectedKey, key))
+                if (assetName.IsEquivalentTo(expectedKey))
                     animal.Sprite.spriteTexture = texture.Value;
             }
             return texture.IsValueCreated;
         }
 
         /// <summary>Reload building textures.</summary>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
-        private bool ReloadBuildings(string key)
+        private bool ReloadBuildings(IAssetName assetName)
         {
             // get paint mask info
             const string paintMaskSuffix = "_PaintMask";
-            bool isPaintMask = key.EndsWith(paintMaskSuffix, StringComparison.OrdinalIgnoreCase);
+            bool isPaintMask = assetName.BaseName.EndsWith(paintMaskSuffix, StringComparison.OrdinalIgnoreCase);
 
             // get building type
-            string type = Path.GetFileName(key);
+            string type = Path.GetFileName(assetName.Name)!;
             if (isPaintMask)
                 type = type.Substring(0, type.Length - paintMaskSuffix.Length);
 
@@ -718,7 +717,7 @@ namespace StardewModdingAPI.Metadata
                 .ToArray();
 
             // remove from paint mask cache
-            bool removedFromCache = this.RemoveFromPaintMaskCache(key);
+            bool removedFromCache = this.RemoveFromPaintMaskCache(assetName);
 
             // reload textures
             if (buildings.Any())
@@ -734,12 +733,12 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload map seat textures.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <param name="ignoreWorld">Whether the in-game world is fully unloaded (e.g. on the title screen), so there's no need to propagate changes into the world.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
-        private bool ReloadChairTiles(LocalizedContentManager content, string key, bool ignoreWorld)
+        private bool ReloadChairTiles(LocalizedContentManager content, IAssetName assetName, bool ignoreWorld)
         {
-            MapSeat.mapChairTexture = content.Load<Texture2D>(key);
+            MapSeat.mapChairTexture = content.Load<Texture2D>(assetName.Name);
 
             if (!ignoreWorld)
             {
@@ -747,7 +746,7 @@ namespace StardewModdingAPI.Metadata
                 {
                     foreach (MapSeat seat in location.mapSeats.Where(p => p != null))
                     {
-                        if (this.IsSameAssetKey(seat._loadedTextureFile, key))
+                        if (assetName.IsEquivalentTo(seat._loadedTextureFile))
                             seat.overlayTexture = MapSeat.mapChairTexture;
                     }
                 }
@@ -758,9 +757,9 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload critter textures.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns the number of reloaded assets.</returns>
-        private int ReloadCritterTextures(LocalizedContentManager content, string key)
+        private int ReloadCritterTextures(LocalizedContentManager content, IAssetName assetName)
         {
             // get critters
             Critter[] critters =
@@ -768,7 +767,7 @@ namespace StardewModdingAPI.Metadata
                     from location in this.GetLocations()
                     where location.critters != null
                     from Critter critter in location.critters
-                    where this.IsSameAssetKey(critter.sprite?.Texture?.Name, key)
+                    where assetName.IsEquivalentTo(critter.sprite?.Texture?.Name)
                     select critter
                 )
                 .ToArray();
@@ -776,7 +775,7 @@ namespace StardewModdingAPI.Metadata
                 return 0;
 
             // update sprites
-            Texture2D texture = content.Load<Texture2D>(key);
+            Texture2D texture = content.Load<Texture2D>(assetName.Name);
             foreach (var entry in critters)
                 entry.sprite.spriteTexture = texture;
 
@@ -785,11 +784,11 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload the sprites for interior doors.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any doors were affected.</returns>
-        private bool ReloadDoorSprites(LocalizedContentManager content, string key)
+        private bool ReloadDoorSprites(LocalizedContentManager content, IAssetName assetName)
         {
-            Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(key));
+            Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(assetName.Name));
 
             foreach (GameLocation location in this.GetLocations())
             {
@@ -803,7 +802,7 @@ namespace StardewModdingAPI.Metadata
                         continue;
 
                     string curKey = this.Reflection.GetField<string>(door.Sprite, "textureName").GetValue();
-                    if (this.IsSameAssetKey(curKey, key))
+                    if (assetName.IsEquivalentTo(curKey))
                         door.Sprite.texture = texture.Value;
                 }
             }
@@ -827,12 +826,12 @@ namespace StardewModdingAPI.Metadata
         }
 
         /// <summary>Reload the sprites for a fence type.</summary>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
-        private bool ReloadFenceTextures(string key)
+        private bool ReloadFenceTextures(IAssetName assetName)
         {
-            // get fence type
-            if (!int.TryParse(this.GetSegments(key)[1].Substring("Fence".Length), out int fenceType))
+            // get fence type (e.g. LooseSprites/Fence3 => 3)
+            if (!int.TryParse(this.GetSegments(assetName.BaseName)[1].Substring("Fence".Length), out int fenceType))
                 return false;
 
             // get fences
@@ -855,22 +854,22 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload tree textures.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
-        private bool ReloadGrassTextures(LocalizedContentManager content, string key)
+        private bool ReloadGrassTextures(LocalizedContentManager content, IAssetName assetName)
         {
             Grass[] grasses =
                 (
                     from location in this.GetLocations()
                     from grass in location.terrainFeatures.Values.OfType<Grass>()
-                    where this.IsSameAssetKey(grass.textureName(), key)
+                    where assetName.IsEquivalentTo(grass.textureName())
                     select grass
                 )
                 .ToArray();
 
             if (grasses.Any())
             {
-                Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(key));
+                Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(assetName.Name));
                 foreach (Grass grass in grasses)
                     grass.texture = texture;
                 return true;
@@ -932,11 +931,11 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload the disposition data for matching NPCs.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any NPCs were affected.</returns>
-        private bool ReloadNpcDispositions(LocalizedContentManager content, string key)
+        private bool ReloadNpcDispositions(LocalizedContentManager content, IAssetName assetName)
         {
-            IDictionary<string, string> data = content.Load<Dictionary<string, string>>(key);
+            IDictionary<string, string> data = content.Load<Dictionary<string, string>>(assetName.Name);
             bool changed = false;
             foreach (NPC npc in this.GetCharacters())
             {
@@ -953,16 +952,16 @@ namespace StardewModdingAPI.Metadata
         /// <summary>Reload the sprites for matching NPCs.</summary>
         /// <param name="keys">The asset keys to reload.</param>
         /// <param name="propagated">The asset keys which have been propagated.</param>
-        private void ReloadNpcSprites(IEnumerable<string> keys, IDictionary<string, bool> propagated)
+        private void ReloadNpcSprites(IEnumerable<IAssetName> keys, IDictionary<IAssetName, bool> propagated)
         {
             // get NPCs
-            HashSet<string> lookup = new HashSet<string>(keys, StringComparer.OrdinalIgnoreCase);
+            IDictionary<string, IAssetName> lookup = keys.ToDictionary(p => p.Name, StringComparer.OrdinalIgnoreCase);
             var characters =
                 (
                     from npc in this.GetCharacters()
                     let key = this.NormalizeAssetNameIgnoringEmpty(npc.Sprite?.Texture?.Name)
-                    where key != null && lookup.Contains(key)
-                    select new { Npc = npc, Key = key }
+                    where key != null && lookup.ContainsKey(key)
+                    select new { Npc = npc, AssetName = lookup[key] }
                 )
                 .ToArray();
             if (!characters.Any())
@@ -971,56 +970,56 @@ namespace StardewModdingAPI.Metadata
             // update sprite
             foreach (var target in characters)
             {
-                target.Npc.Sprite.spriteTexture = this.LoadAndDisposeIfNeeded(target.Npc.Sprite.spriteTexture, target.Key);
-                propagated[target.Key] = true;
+                target.Npc.Sprite.spriteTexture = this.LoadAndDisposeIfNeeded(target.Npc.Sprite.spriteTexture, target.AssetName.Name);
+                propagated[target.AssetName] = true;
             }
         }
 
         /// <summary>Reload the portraits for matching NPCs.</summary>
         /// <param name="keys">The asset key to reload.</param>
         /// <param name="propagated">The asset keys which have been propagated.</param>
-        private void ReloadNpcPortraits(IEnumerable<string> keys, IDictionary<string, bool> propagated)
+        private void ReloadNpcPortraits(IEnumerable<IAssetName> keys, IDictionary<IAssetName, bool> propagated)
         {
             // get NPCs
-            HashSet<string> lookup = new HashSet<string>(keys, StringComparer.OrdinalIgnoreCase);
+            IDictionary<string, IAssetName> lookup = keys.ToDictionary(p => p.Name, StringComparer.OrdinalIgnoreCase);
             var characters =
                 (
                     from npc in this.GetCharacters()
                     where npc.isVillager()
 
                     let key = this.NormalizeAssetNameIgnoringEmpty(npc.Portrait?.Name)
-                    where key != null && lookup.Contains(key)
-                    select new { Npc = npc, Key = key }
+                    where key != null && lookup.ContainsKey(key)
+                    select new { Npc = npc, AssetName = lookup[key] }
                 )
                 .ToList();
 
             // special case: Gil is a private NPC field on the AdventureGuild class (only used for the portrait)
             {
                 string gilKey = this.NormalizeAssetNameIgnoringEmpty("Portraits/Gil");
-                if (lookup.Contains(gilKey))
+                if (lookup.TryGetValue(gilKey, out IAssetName assetName))
                 {
                     GameLocation adventureGuild = Game1.getLocationFromName("AdventureGuild");
                     if (adventureGuild != null)
-                        characters.Add(new { Npc = this.Reflection.GetField<NPC>(adventureGuild, "Gil").GetValue(), Key = gilKey });
+                        characters.Add(new { Npc = this.Reflection.GetField<NPC>(adventureGuild, "Gil").GetValue(), AssetName = assetName });
                 }
             }
 
             // update portrait
             foreach (var target in characters)
             {
-                target.Npc.Portrait = this.LoadAndDisposeIfNeeded(target.Npc.Portrait, target.Key);
-                propagated[target.Key] = true;
+                target.Npc.Portrait = this.LoadAndDisposeIfNeeded(target.Npc.Portrait, target.AssetName.Name);
+                propagated[target.AssetName] = true;
             }
         }
 
         /// <summary>Reload the sprites for matching players.</summary>
-        /// <param name="key">The asset key to reload.</param>
-        private bool ReloadPlayerSprites(string key)
+        /// <param name="assetName">The asset name to reload.</param>
+        private bool ReloadPlayerSprites(IAssetName assetName)
         {
             Farmer[] players =
                 (
                     from player in Game1.getOnlineFarmers()
-                    where this.IsSameAssetKey(player.getTexture(), key)
+                    where assetName.IsEquivalentTo(player.getTexture())
                     select player
                 )
                 .ToArray();
@@ -1036,11 +1035,11 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload suspension bridge textures.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
-        private bool ReloadSuspensionBridges(LocalizedContentManager content, string key)
+        private bool ReloadSuspensionBridges(LocalizedContentManager content, IAssetName assetName)
         {
-            Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(key));
+            Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(assetName.Name));
 
             foreach (GameLocation location in this.GetLocations(buildingInteriors: false))
             {
@@ -1059,10 +1058,10 @@ namespace StardewModdingAPI.Metadata
 
         /// <summary>Reload tree textures.</summary>
         /// <param name="content">The content manager through which to reload the asset.</param>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <param name="type">The type to reload.</param>
         /// <returns>Returns whether any textures were reloaded.</returns>
-        private bool ReloadTreeTextures(LocalizedContentManager content, string key, int type)
+        private bool ReloadTreeTextures(LocalizedContentManager content, IAssetName assetName, int type)
         {
             Tree[] trees = this.GetLocations()
                 .SelectMany(p => p.terrainFeatures.Values.OfType<Tree>())
@@ -1071,7 +1070,7 @@ namespace StardewModdingAPI.Metadata
 
             if (trees.Any())
             {
-                Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(key));
+                Lazy<Texture2D> texture = new Lazy<Texture2D>(() => content.Load<Texture2D>(assetName.Name));
                 foreach (Tree tree in trees)
                     tree.texture = texture;
                 return true;
@@ -1084,12 +1083,12 @@ namespace StardewModdingAPI.Metadata
         ** Reload data methods
         ****/
         /// <summary>Reload the dialogue data for matching NPCs.</summary>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any assets were reloaded.</returns>
-        private bool ReloadNpcDialogue(string key)
+        private bool ReloadNpcDialogue(IAssetName assetName)
         {
             // get NPCs
-            string name = Path.GetFileName(key);
+            string name = Path.GetFileName(assetName.Name);
             NPC[] villagers = this.GetCharacters().Where(npc => npc.Name == name && npc.isVillager()).ToArray();
             if (!villagers.Any())
                 return false;
@@ -1114,12 +1113,12 @@ namespace StardewModdingAPI.Metadata
         }
 
         /// <summary>Reload the schedules for matching NPCs.</summary>
-        /// <param name="key">The asset key to reload.</param>
+        /// <param name="assetName">The asset name to reload.</param>
         /// <returns>Returns whether any assets were reloaded.</returns>
-        private bool ReloadNpcSchedules(string key)
+        private bool ReloadNpcSchedules(IAssetName assetName)
         {
             // get NPCs
-            string name = Path.GetFileName(key);
+            string name = Path.GetFileName(assetName.Name);
             NPC[] villagers = this.GetCharacters().Where(npc => npc.Name == name && npc.isVillager()).ToArray();
             if (!villagers.Any())
                 return false;
@@ -1243,39 +1242,6 @@ namespace StardewModdingAPI.Metadata
             return this.AssertAndNormalizeAssetName(path);
         }
 
-        /// <summary>Get whether a given asset key is equivalent to a normalized asset key, ignoring unimportant differences like capitalization and formatting.</summary>
-        /// <param name="actualKey">The actual key to check.</param>
-        /// <param name="normalizedKey">The key to match, already normalized via <see cref="AssertAndNormalizeAssetName"/> or <see cref="NormalizeAssetNameIgnoringEmpty"/>.</param>
-        private bool IsSameAssetKey(string actualKey, string normalizedKey)
-        {
-            if (actualKey is null || normalizedKey is null)
-                return false;
-
-            return normalizedKey.Equals(PathUtilities.NormalizeAssetName(actualKey), StringComparison.OrdinalIgnoreCase);
-        }
-
-        /// <summary>Get whether a key starts with a substring after the substring is normalized.</summary>
-        /// <param name="key">The key to check.</param>
-        /// <param name="rawSubstring">The substring to normalize and find.</param>
-        private bool KeyStartsWith(string key, string rawSubstring)
-        {
-            if (string.IsNullOrWhiteSpace(key) || string.IsNullOrWhiteSpace(rawSubstring))
-                return false;
-
-            return key.StartsWith(this.NormalizeAssetNameIgnoringEmpty(rawSubstring), StringComparison.OrdinalIgnoreCase);
-        }
-
-        /// <summary>Get whether a normalized asset key is in the given folder.</summary>
-        /// <param name="key">The normalized asset key (like <c>Animals/cat</c>).</param>
-        /// <param name="folder">The key folder (like <c>Animals</c>); doesn't need to be normalized.</param>
-        /// <param name="allowSubfolders">Whether to return true if the key is inside a subfolder of the <paramref name="folder"/>.</param>
-        private bool IsInFolder(string key, string folder, bool allowSubfolders = false)
-        {
-            return
-                this.KeyStartsWith(key, $"{folder}/")
-                && (allowSubfolders || this.CountSegments(key) == this.CountSegments(folder) + 1);
-        }
-
         /// <summary>Get the segments in a path (e.g. 'a/b' is 'a' and 'b').</summary>
         /// <param name="path">The path to check.</param>
         private string[] GetSegments(string path)
@@ -1285,13 +1251,6 @@ namespace StardewModdingAPI.Metadata
                 : Array.Empty<string>();
         }
 
-        /// <summary>Count the number of segments in a path (e.g. 'a/b' is 2).</summary>
-        /// <param name="path">The path to check.</param>
-        private int CountSegments(string path)
-        {
-            return this.GetSegments(path).Length;
-        }
-
         /// <summary>Load a texture, and dispose the old one if <see cref="AggressiveMemoryOptimizations"/> is enabled and it's different from the new instance.</summary>
         /// <param name="oldTexture">The previous texture to dispose.</param>
         /// <param name="key">The asset key to load.</param>
@@ -1315,8 +1274,8 @@ namespace StardewModdingAPI.Metadata
         }
 
         /// <summary>Remove a case-insensitive key from the paint mask cache.</summary>
-        /// <param name="key">The paint mask asset key.</param>
-        private bool RemoveFromPaintMaskCache(string key)
+        /// <param name="assetName">The paint mask asset name.</param>
+        private bool RemoveFromPaintMaskCache(IAssetName assetName)
         {
             // make cache case-insensitive
             // This is needed for cache invalidation since mods may specify keys with a different capitalization
@@ -1324,7 +1283,7 @@ namespace StardewModdingAPI.Metadata
                 BuildingPainter.paintMaskLookup = new Dictionary<string, List<List<int>>>(BuildingPainter.paintMaskLookup, StringComparer.OrdinalIgnoreCase);
 
             // remove key from cache
-            return BuildingPainter.paintMaskLookup.Remove(key);
+            return BuildingPainter.paintMaskLookup.Remove(assetName.Name);
         }
 
         /// <summary>Metadata about a location used in asset propagation.</summary>