BASE changed interface

Core/SessionStore.cs

@@ -0,0 +1,96 @@
+using System.IO;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace FoxBrowser.Core;
+
+/// <summary>
+/// Snapshot of a single tab persisted to disk.
+/// All properties are nullable so old session files remain forward-compatible.
+/// </summary>
+public sealed class TabSnapshot
+{
+    public string  Address       { get; init; } = "https://www.google.com";
+    public string  Title         { get; init; } = "Нова вкладка";
+    public bool    IsAudioOnly   { get; init; }
+    public double  ScrollY       { get; init; }
+    public double  MediaPosition { get; init; }
+    public bool    WasPlaying    { get; init; }
+}
+
+public sealed class Session
+{
+    public List<TabSnapshot> Tabs          { get; init; } = new();
+    public int               ActiveTabIndex { get; init; }
+}
+
+/// <summary>
+/// Saves and loads the browser session (open tabs + per-tab state) to a JSON
+/// file in LocalApplicationData\FoxBrowser\session.json.
+///
+/// Crash-recovery strategy: the file is re-written after every successful
+/// NavigationCompleted so a hard crash never loses more than one page load.
+/// </summary>
+public static class SessionStore
+{
+    private static readonly string SessionPath = Path.Combine(
+        Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+        "FoxBrowser", "session.json");
+
+    private static readonly JsonSerializerOptions JsonOptions = new()
+    {
+        WriteIndented         = true,
+        DefaultIgnoreCondition = JsonIgnoreCondition.Never,
+    };
+
+    public static async Task SaveAsync(IEnumerable<BrowserTab> tabs, int activeIndex)
+    {
+        try
+        {
+            var snapshots = tabs.Select(t => new TabSnapshot
+            {
+                Address       = t.Address,
+                Title         = t.Title,
+                IsAudioOnly   = t.IsAudioOnly,
+                ScrollY       = t.ScrollY,
+                MediaPosition = t.MediaPosition,
+                WasPlaying    = t.WasPlaying,
+            }).ToList();
+
+            if (snapshots.Count == 0) return;
+
+            var session = new Session
+            {
+                Tabs           = snapshots,
+                ActiveTabIndex = Math.Clamp(activeIndex, 0, snapshots.Count - 1),
+            };
+
+            Directory.CreateDirectory(Path.GetDirectoryName(SessionPath)!);
+            var json = JsonSerializer.Serialize(session, JsonOptions);
+            // Write to a temp file first, then replace atomically — avoids
+            // truncating the real file if the process is killed mid-write.
+            var tmp = SessionPath + ".tmp";
+            await File.WriteAllTextAsync(tmp, json);
+            File.Move(tmp, SessionPath, overwrite: true);
+        }
+        catch (Exception ex)
+        {
+            System.Diagnostics.Debug.WriteLine($"[SessionStore] Save failed: {ex.Message}");
+        }
+    }
+
+    public static async Task<Session?> LoadAsync()
+    {
+        if (!File.Exists(SessionPath)) return null;
+        try
+        {
+            var json = await File.ReadAllTextAsync(SessionPath);
+            return JsonSerializer.Deserialize<Session>(json);
+        }
+        catch (Exception ex)
+        {
+            System.Diagnostics.Debug.WriteLine($"[SessionStore] Load failed: {ex.Message}");
+            return null;
+        }
+    }
+}