1 files changed, 88 insertions, 0 deletions
diff --git a/Emby.Naming/Video/ExtraRuleResolver.cs b/Emby.Naming/Video/ExtraRuleResolver.cs
new file mode 100644
index 000000000..0970e509a
--- /dev/null
+++ b/Emby.Naming/Video/ExtraRuleResolver.cs
@@ -0,0 +1,88 @@
+using System;
+using System.IO;
+using System.Text.RegularExpressions;
+using Emby.Naming.Audio;
+using Emby.Naming.Common;
+
+namespace Emby.Naming.Video
+{
+    /// <summary>
+    /// Resolve if file is extra for video.
+    /// </summary>
+    public static class ExtraRuleResolver
+    {
+        private static readonly char[] _digits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
+
+        /// <summary>
+        /// Attempts to resolve if file is extra.
+        /// </summary>
+        /// <param name="path">Path to file.</param>
+        /// <param name="namingOptions">The naming options.</param>
+        /// <returns>Returns <see cref="ExtraResult"/> object.</returns>
+        public static ExtraResult GetExtraInfo(string path, NamingOptions namingOptions)
+        {
+            var result = new ExtraResult();
+
+            for (var i = 0; i < namingOptions.VideoExtraRules.Length; i++)
+            {
+                var rule = namingOptions.VideoExtraRules[i];
+                if ((rule.MediaType == MediaType.Audio && !AudioFileParser.IsAudioFile(path, namingOptions))
+                    || (rule.MediaType == MediaType.Video && !VideoResolver.IsVideoFile(path, namingOptions)))
+                {
+                    continue;
+                }
+
+                var pathSpan = path.AsSpan();
+                if (rule.RuleType == ExtraRuleType.Filename)
+                {
+                    var filename = Path.GetFileNameWithoutExtension(pathSpan);
+
+                    if (filename.Equals(rule.Token, StringComparison.OrdinalIgnoreCase))
+                    {
+                        result.ExtraType = rule.ExtraType;
+                        result.Rule = rule;
+                    }
+                }
+                else if (rule.RuleType == ExtraRuleType.Suffix)
+                {
+                    // Trim the digits from the end of the filename so we can recognize things like -trailer2
+                    var filename = Path.GetFileNameWithoutExtension(pathSpan).TrimEnd(_digits);
+
+                    if (filename.EndsWith(rule.Token, StringComparison.OrdinalIgnoreCase))
+                    {
+                        result.ExtraType = rule.ExtraType;
+                        result.Rule = rule;
+                    }
+                }
+                else if (rule.RuleType == ExtraRuleType.Regex)
+                {
+                    var filename = Path.GetFileName(path);
+
+                    var isMatch = Regex.IsMatch(filename, rule.Token, RegexOptions.IgnoreCase | RegexOptions.Compiled);
+
+                    if (isMatch)
+                    {
+                        result.ExtraType = rule.ExtraType;
+                        result.Rule = rule;
+                    }
+                }
+                else if (rule.RuleType == ExtraRuleType.DirectoryName)
+                {
+                    var directoryName = Path.GetFileName(Path.GetDirectoryName(pathSpan));
+                    if (directoryName.Equals(rule.Token, StringComparison.OrdinalIgnoreCase))
+                    {
+                        result.ExtraType = rule.ExtraType;
+                        result.Rule = rule;
+                    }
+                }
+
+                if (result.ExtraType != null)
+                {
+                    return result;
+                }
+            }
+
+            return result;
+        }
+    }
+}