Implement CONFIG mixer and native profile persistence

2026-07-29 10:22:22 -04:00
parent bcfb3848bc
commit 1678459b05
16 changed files with 1037 additions and 32 deletions
--- a/engine/Age.Engine/Persistence/Sys4PersistencePaths.cs
+++ b/engine/Age.Engine/Persistence/Sys4PersistencePaths.cs
@@ -0,0 +1,98 @@
+using System.Globalization;
+using Age.Engine.Sys4;
+
+namespace Age.Engine.Persistence;
+
+/// <summary>
+/// Resolves the two native AGE persistence locations from one SYS4INI profile. Native mode follows
+/// USEAPPDATAFOLDER plus the independent SAVEPATH and REGFILEPATH values. A profile override replaces
+/// the resolved REGFILEPATH directory while preserving SAVEPATH's relative tail beneath it.
+/// </summary>
+public readonly record struct Sys4PersistencePaths(
+    string SaveDirectory,
+    string Sys4RegIniPath)
+{
+    public static Sys4PersistencePaths ResolveNative(
+        Sys4StartupSettings startupSettings,
+        string gameRoot,
+        string? localApplicationDataRoot = null)
+    {
+        ArgumentNullException.ThrowIfNull(startupSettings);
+        ArgumentException.ThrowIfNullOrWhiteSpace(gameRoot);
+
+        bool useAppData = int.TryParse(
+            startupSettings.GetValueOrDefault("USEAPPDATAFOLDER"),
+            NumberStyles.Integer,
+            CultureInfo.InvariantCulture,
+            out int useAppDataValue)
+            && useAppDataValue != 0;
+        string root = useAppData
+            ? localApplicationDataRoot
+                ?? Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData)
+            : gameRoot;
+        if (string.IsNullOrWhiteSpace(root))
+            throw new InvalidDataException("Native AGE persistence root is unavailable.");
+
+        string saveDirectory = CombineWindowsRelativePath(
+            root, startupSettings.GetValueOrDefault("SAVEPATH"), "SAVEPATH");
+        string settingsDirectory = CombineWindowsRelativePath(
+            root, startupSettings.GetValueOrDefault("REGFILEPATH"), "REGFILEPATH");
+        return new Sys4PersistencePaths(
+            saveDirectory,
+            Path.Combine(settingsDirectory, Sys4RegIniStore.FileName));
+    }
+
+    public static Sys4PersistencePaths ResolveProfileOverride(
+        Sys4StartupSettings startupSettings,
+        string profileRoot)
+    {
+        ArgumentNullException.ThrowIfNull(startupSettings);
+        ArgumentException.ThrowIfNullOrWhiteSpace(profileRoot);
+
+        IReadOnlyList<string> settingsComponents = ParseWindowsRelativePath(
+            startupSettings.GetValueOrDefault("REGFILEPATH"), "REGFILEPATH");
+        IReadOnlyList<string> saveComponents = ParseWindowsRelativePath(
+            startupSettings.GetValueOrDefault("SAVEPATH"), "SAVEPATH");
+        if (settingsComponents.Count > saveComponents.Count
+            || !settingsComponents
+                .Select((component, index) => string.Equals(
+                    component, saveComponents[index], StringComparison.OrdinalIgnoreCase))
+                .All(matches => matches))
+        {
+            throw new InvalidDataException(
+                "SAVEPATH is not beneath REGFILEPATH; one profile-root override cannot safely " +
+                "represent both native AGE persistence locations.");
+        }
+
+        string root = Path.GetFullPath(profileRoot);
+        string saveDirectory = saveComponents
+            .Skip(settingsComponents.Count)
+            .Aggregate(root, Path.Combine);
+        return new Sys4PersistencePaths(
+            saveDirectory,
+            Path.Combine(root, Sys4RegIniStore.FileName));
+    }
+
+    private static string CombineWindowsRelativePath(
+        string root,
+        string? relative,
+        string settingName)
+        => ParseWindowsRelativePath(relative, settingName)
+            .Aggregate(Path.GetFullPath(root), Path.Combine);
+
+    private static IReadOnlyList<string> ParseWindowsRelativePath(
+        string? relative,
+        string settingName)
+    {
+        string[] components = (relative ?? "").Split(
+            ['\\', '/'],
+            StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
+        foreach (string component in components)
+        {
+            if (component is "." or ".." || component.Contains(':'))
+                throw new InvalidDataException(
+                    $"{settingName} contains unsafe component '{component}'.");
+        }
+        return components;
+    }
+}