Initial commit: Star of Words Unity project

Snapshot of the existing Unity 6 language-learning word game before any
refactoring. Adds Unity .gitignore and .gitattributes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/GoogleMobileAds/Editor/Utils.cs

@@ -0,0 +1,115 @@
+// Copyright (C) 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text.RegularExpressions;
+
+namespace GoogleMobileAds.Editor
+{
+    /*
+    * Utils class that contains helper methods.
+    */
+    public static class Utils
+    {
+        //  Android library plugins directory that contains custom gradle templates.
+        internal const string AndroidPluginsDir = "Assets/Plugins/Android";
+
+        // Extracts an Android Gradle Plugin version number from the contents of a *.gradle file.
+        // This should work for Unity 2022.1 and below.
+        // Ex.
+        //   classpath 'com.android.tools.build:gradle:4.0.1'
+        private static Regex androidGradlePluginVersionExtract_legacy =
+            new Regex(@"^\s*classpath\s+['""]com\.android\.tools\.build:gradle:([^'""]+)['""]$");
+
+        // Extracts an Android Gradle Plugin version number from the contents of a *.gradle file for
+        // Unity 2022.2+ or 2023.1+.
+        // Ex.
+        //   id 'com.android.application' version '7.1.2' apply false
+        private static Regex androidGradlePluginVersionExtract =
+            new Regex(@"^\s*id\s+['""]com\.android\.application['""] version ['""]([^'""]+)['""]");
+
+        // Extracts major.minor[.patch] version numbers from a string.
+        private static readonly Regex versionParseRegex =
+            new Regex(@"^(\d+)\.(\d+)(?:\.(\d+))?", RegexOptions.Compiled);
+
+        /// <summary>
+        /// Get the Android Gradle Plugin version used by the Unity project.
+        /// </summary>
+        public static Version AndroidGradlePluginVersion
+        {
+            get
+            {
+                return ParseVersion(GetAndroidGradlePluginVersionString());
+            }
+        }
+
+        private static string GetAndroidGradlePluginVersionString()
+        {
+            if (!Directory.Exists(AndroidPluginsDir))
+            {
+                return DefaultAndroidGradlePlugin();
+            }
+            var gradleTemplates = Directory.GetFiles(AndroidPluginsDir, "*.gradle",
+                                                     SearchOption.TopDirectoryOnly);
+            foreach (var path in gradleTemplates)
+            {
+                foreach (var line in File.ReadLines(path))
+                {
+                    var match = androidGradlePluginVersionExtract_legacy.Match(line);
+                    if (match != null && match.Success)
+                    {
+                        return match.Result("$1");
+                    }
+                    match = androidGradlePluginVersionExtract.Match(line);
+                    if (match != null && match.Success)
+                    {
+                        return match.Result("$1");
+                    }
+                }
+            }
+            return DefaultAndroidGradlePlugin();
+        }
+
+        private static Version ParseVersion(string versionStr)
+        {
+            var match = versionParseRegex.Match(versionStr);
+            if (match.Success)
+            {
+                int major = int.Parse(match.Groups[1].Value);
+                int minor = int.Parse(match.Groups[2].Value);
+                int patch = match.Groups[3].Success ? int.Parse(match.Groups[3].Value) : 0;
+                return new Version(major, minor, patch);
+            }
+            return new Version(0, 0, 0);
+        }
+
+        // These values are based on the Unity documentation for the latest version of Unity. See
+        // https://docs.unity3d.com/2023.2/Documentation/Manual/android-gradle-overview.html
+        // https://docs.unity3d.com/6000.0/Documentation/Manual/android-gradle-version-compatibility.html
+        private static string DefaultAndroidGradlePlugin()
+        {
+#if UNITY_6000_0_OR_NEWER
+            return "8.3.0";
+#elif UNITY_2023_2_OR_NEWER
+            return "7.3.1";
+#elif UNITY_2022_2_OR_NEWER
+            return "7.1.2";
+#else
+            return "4.0.1";
+#endif
+        }
+    }
+}