App

src/Alma.App/Services/FolderService.cs

@@ -0,0 +1,51 @@
+namespace Alma.Services;
+
+public class FolderService : IFolderService
+{
+    public string? ConfigRoot { get; }
+    public string AppData { get; }
+
+    public FolderService()
+    {
+        ConfigRoot = GetConfigHomePath();
+        AppData = GetAppDataPath();
+
+        if (!Directory.Exists(AppData)) Directory.CreateDirectory(AppData);
+    }
+
+    private static string? GetConfigHomePath()
+    {
+        var configHomeProviders = new List<Func<string?>>
+        {
+            () => Environment.GetEnvironmentVariable("XDG_CONFIG_HOME"),
+            () => Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), ".config")
+        };
+
+        var configHome = EnumerateProviders(configHomeProviders);
+        return configHome == null ? null : Path.Combine(configHome, "alma");
+    }
+
+    private static string GetAppDataPath()
+    {
+        var appDataProviders = new List<Func<string?>>
+        {
+            () => Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData)
+        };
+
+        var appData = EnumerateProviders(appDataProviders) ?? Environment.CurrentDirectory;
+        return Path.Combine(appData, "alma");
+    }
+
+    private static string? EnumerateProviders(List<Func<string?>> providers)
+    {
+        string? result = null;
+
+        foreach (var provider in providers)
+        {
+            result = provider();
+            if (result is not null && Directory.Exists(result)) break;
+        }
+
+        return result;
+    }
+}