feat: align legacy operator and playout behavior

src/MBN_STOCK_WEBVIEW.LegacyApplication/Comparison/LegacyComparisonWorkflowController.cs

@@ -33,6 +33,7 @@ public sealed class LegacyComparisonWorkflowController
     private long _draftSequence;
     private int _domesticSearchVersion;
     private int _worldSearchVersion;
+    private int _activationGeneration;
     private bool _isBusy;
 
     public LegacyComparisonWorkflowController(
@@ -45,12 +46,44 @@ public sealed class LegacyComparisonWorkflowController
 
     public LegacyComparisonWorkflowSnapshot Current => CreateSnapshot();
 
+    /// <summary>
+    /// Recreates UC3's per-control state before its saved CP949 pairs are loaded for
+    /// a new tab activation. Search and pair-load generations invalidate completions
+    /// that belong to the discarded control instance.
+    /// </summary>
+    public LegacyComparisonWorkflowSnapshot ResetForTabActivation()
+    {
+        Interlocked.Increment(ref _activationGeneration);
+        Interlocked.Increment(ref _domesticSearchVersion);
+        Interlocked.Increment(ref _worldSearchVersion);
+        _domesticResults = [];
+        _worldResults = [];
+        _savedPairs = [];
+        _firstTarget = null;
+        _secondTarget = null;
+        _selectedDomesticResultId = null;
+        _selectedWorldResultId = null;
+        _selectedFixedTargetId = null;
+        _selectedPairId = null;
+        _domesticQuery = string.Empty;
+        _worldQuery = string.Empty;
+        _domesticError = string.Empty;
+        _worldError = string.Empty;
+        _statusMessage = string.Empty;
+        _domesticStatus = LegacyComparisonSearchStatus.Idle;
+        _worldStatus = LegacyComparisonSearchStatus.Idle;
+        _statusKind = LegacyOperatorStatusKind.Neutral;
+        _isBusy = false;
+        Touch();
+        return CreateSnapshot();
+    }
+
     public async Task<LegacyComparisonWorkflowSnapshot> SearchDomesticAsync(
         string query,
         CancellationToken cancellationToken = default)
     {
         var normalizedQuery = NormalizeSearchQuery(query);
-        var version = ++_domesticSearchVersion;
+        var version = Interlocked.Increment(ref _domesticSearchVersion);
         _domesticQuery = normalizedQuery;
         _domesticStatus = LegacyComparisonSearchStatus.Loading;
         _domesticError = string.Empty;
@@ -64,7 +97,7 @@ public sealed class LegacyComparisonWorkflowController
                 normalizedQuery,
                 LegacyComparisonWorkflowCatalog.DomesticMaximumResults,
                 cancellationToken).ConfigureAwait(false);
-            if (version != _domesticSearchVersion)
+            if (version != Volatile.Read(ref _domesticSearchVersion))
             {
                 return CreateSnapshot();
             }
@@ -81,7 +114,7 @@ public sealed class LegacyComparisonWorkflowController
         }
         catch (OperationCanceledException)
         {
-            if (version == _domesticSearchVersion)
+            if (version == Volatile.Read(ref _domesticSearchVersion))
             {
                 _domesticStatus = LegacyComparisonSearchStatus.Idle;
                 _domesticError = string.Empty;
@@ -92,7 +125,7 @@ public sealed class LegacyComparisonWorkflowController
         }
         catch
         {
-            if (version == _domesticSearchVersion)
+            if (version == Volatile.Read(ref _domesticSearchVersion))
             {
                 _domesticResults = [];
                 _domesticStatus = LegacyComparisonSearchStatus.Error;
@@ -110,7 +143,7 @@ public sealed class LegacyComparisonWorkflowController
     {
         // UC3's blank world query loaded the complete US/TW universe, so blank remains valid.
         var normalizedQuery = NormalizeSearchQuery(query);
-        var version = ++_worldSearchVersion;
+        var version = Interlocked.Increment(ref _worldSearchVersion);
         _worldQuery = normalizedQuery;
         _worldStatus = LegacyComparisonSearchStatus.Loading;
         _worldError = string.Empty;
@@ -124,7 +157,7 @@ public sealed class LegacyComparisonWorkflowController
                 normalizedQuery,
                 LegacyComparisonWorkflowCatalog.WorldMaximumResults,
                 cancellationToken).ConfigureAwait(false);
-            if (version != _worldSearchVersion)
+            if (version != Volatile.Read(ref _worldSearchVersion))
             {
                 return CreateSnapshot();
             }
@@ -141,7 +174,7 @@ public sealed class LegacyComparisonWorkflowController
         }
         catch (OperationCanceledException)
         {
-            if (version == _worldSearchVersion)
+            if (version == Volatile.Read(ref _worldSearchVersion))
             {
                 _worldStatus = LegacyComparisonSearchStatus.Idle;
                 _worldError = string.Empty;
@@ -152,7 +185,7 @@ public sealed class LegacyComparisonWorkflowController
         }
         catch
         {
-            if (version == _worldSearchVersion)
+            if (version == Volatile.Read(ref _worldSearchVersion))
             {
                 _worldResults = [];
                 _worldStatus = LegacyComparisonSearchStatus.Error;
@@ -220,6 +253,7 @@ public sealed class LegacyComparisonWorkflowController
     public async Task<LegacyComparisonWorkflowSnapshot> LoadSavedPairsAsync(
         CancellationToken cancellationToken = default)
     {
+        var activationGeneration = Volatile.Read(ref _activationGeneration);
         BeginBusy();
         try
         {
@@ -251,6 +285,11 @@ public sealed class LegacyComparisonWorkflowController
                 }
             }
 
+            if (activationGeneration != Volatile.Read(ref _activationGeneration))
+            {
+                return CreateSnapshot();
+            }
+
             _savedPairs = candidate;
             _pairSequence = Math.Max(_pairSequence, candidate.Count);
             _selectedPairId = candidate.FirstOrDefault()?.RowId;
@@ -261,13 +300,21 @@ public sealed class LegacyComparisonWorkflowController
         }
         catch
         {
+            if (activationGeneration != Volatile.Read(ref _activationGeneration))
+            {
+                return CreateSnapshot();
+            }
+
             _statusMessage = "CP949 종목비교.dat를 안전하게 불러오지 못했습니다.";
             _statusKind = LegacyOperatorStatusKind.Error;
             throw;
         }
         finally
         {
-            EndBusy();
+            if (activationGeneration == Volatile.Read(ref _activationGeneration))
+            {
+                EndBusy();
+            }
         }
 
         return CreateSnapshot();

src/MBN_STOCK_WEBVIEW.LegacyApplication/LegacyFixedActionCatalog.cs

@@ -104,7 +104,6 @@ public sealed class LegacyFixedAction
 public sealed record LegacyMaterializedFixedAction(
     LegacyFixedAction Action,
     LegacyFixedSelection Selection,
-    LegacyMovingAverageSelection MovingAverages,
     LegacyFixedRuntimeAsset RuntimeAsset);
 
 public sealed class LegacyFixedSection
@@ -262,8 +261,7 @@ public sealed class LegacyFixedActionCatalog
 
     public LegacyMaterializedFixedAction Materialize(
         string actionId,
-        DateTimeOffset localNow,
-        LegacyMovingAverageSelection movingAverages = default)
+        DateTimeOffset localNow)
     {
         var action = GetAction(actionId);
         if (!action.Available)
@@ -271,14 +269,9 @@ public sealed class LegacyFixedActionCatalog
             throw new InvalidOperationException(action.Prerequisite);
         }
 
-        var trustedMovingAverages = action.SupportsMovingAverages
-            ? movingAverages
-            : default;
         var graphicType = action.DynamicNxtSession
             ? localNow.Hour <= 12 ? "PRE_MARKET" : "AFTER_MARKET"
-            : action.SupportsMovingAverages
-                ? MovingAverageText(trustedMovingAverages)
-                : action.Selection.GraphicType;
+            : action.Selection.GraphicType;
         var dataCode = action.DynamicDate
             ? localNow.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture)
             : action.Selection.DataCode;
@@ -291,7 +284,6 @@ public sealed class LegacyFixedActionCatalog
         return new LegacyMaterializedFixedAction(
             action,
             selection,
-            trustedMovingAverages,
             RuntimeAssets[action.Market]);
     }
 
@@ -602,21 +594,6 @@ public sealed class LegacyFixedActionCatalog
         }
     }
 
-    private static string MovingAverageText(LegacyMovingAverageSelection movingAverages)
-    {
-        if (movingAverages.Ma5 && movingAverages.Ma20)
-        {
-            return "MA5,MA20";
-        }
-
-        if (movingAverages.Ma5)
-        {
-            return "MA5";
-        }
-
-        return movingAverages.Ma20 ? "MA20" : string.Empty;
-    }
-
     private static LegacyFixedMarket ParseMarket(string value) => value switch
     {
         "overseas" => LegacyFixedMarket.Overseas,

src/MBN_STOCK_WEBVIEW.LegacyApplication/LegacyIndustrySelectionWorkflow.cs

@@ -82,6 +82,26 @@ public sealed class LegacyIndustrySelectionWorkflow
 
     public LegacyIndustrySelectionSnapshot Current => CreateSnapshot();
 
+    /// <summary>
+    /// Recreates the observable UC2 state for one tab activation. The generation
+    /// increment prevents a request started by the discarded control from restoring
+    /// its rows after the operator has re-entered the tab.
+    /// </summary>
+    public LegacyIndustrySelectionSnapshot ResetForTabActivation(IndustryMarket market)
+    {
+        ValidateMarket(market);
+        Interlocked.Increment(ref _loadGeneration);
+        _market = market;
+        _industries = NoIndustries;
+        _actions = LegacyIndustryActionCatalog.GetActions(market);
+        _selectedIndex = null;
+        _selectedIndustry = null;
+        _firstIndustry = null;
+        _secondIndustry = null;
+        Touch();
+        return CreateSnapshot();
+    }
+
     public async Task<LegacyIndustrySelectionSnapshot> LoadMarketAsync(
         IndustryMarket market,
         CancellationToken cancellationToken = default)

src/MBN_STOCK_WEBVIEW.LegacyApplication/LegacyOperatorPlayoutModels.cs

@@ -53,4 +53,7 @@ public sealed record LegacyOperatorPlayoutSnapshot(
     bool BackgroundEnabled,
     string BackgroundFileName,
     bool CanChangeBackground,
-    string Message);
+    string Message)
+{
+    public bool IsTakeOutCompletionPending { get; init; }
+}

src/MBN_STOCK_WEBVIEW.LegacyApplication/LegacyOverseasSelectionWorkflow.cs

@@ -273,6 +273,41 @@ public sealed class LegacyOverseasSelectionWorkflow
         }
     }
 
+    /// <summary>
+    /// Recreates UC5's per-control search and selection state while retaining the
+    /// MainForm-owned moving-average checkboxes. Incrementing both generations makes
+    /// results from the discarded control stale before they can commit.
+    /// </summary>
+    public LegacyOverseasWorkflowSnapshot ResetForTabActivation()
+    {
+        lock (_sync)
+        {
+            checked
+            {
+                _industryGeneration++;
+                _stockGeneration++;
+            }
+
+            _selectedFixedIndex = null;
+            _industryStatus = LegacyOverseasSearchStatus.Idle;
+            _industryQuery = string.Empty;
+            _industryRetrievedAt = null;
+            _industryResults = NoIndustryResults;
+            _industryIsTruncated = false;
+            _selectedIndustry = null;
+            _industryError = string.Empty;
+            _stockStatus = LegacyOverseasSearchStatus.Idle;
+            _stockQuery = string.Empty;
+            _stockRetrievedAt = null;
+            _stockResults = NoStockResults;
+            _stockIsTruncated = false;
+            _selectedStock = null;
+            _stockError = string.Empty;
+            Touch();
+            return CreateSnapshot();
+        }
+    }
+
     public LegacyOverseasWorkflowSnapshot SelectFixedIndex(string targetId)
     {
         var target = LegacyOverseasActionCatalog.GetFixedIndexTarget(targetId);

src/MBN_STOCK_WEBVIEW.LegacyApplication/LegacyRuntimeStockCutMenuLoader.cs

@@ -0,0 +1,355 @@
+using System.Text;
+
+namespace MBN_STOCK_WEBVIEW.LegacyApplication;
+
+public enum LegacyRuntimeStockCutMenuFailure
+{
+    None,
+    InvalidPath,
+    FileNotFound,
+    FileUnavailable,
+    FileTooLarge,
+    InvalidEncoding,
+    InvalidFormat,
+    TooManyRows,
+    UnknownCut,
+    EmptyMenu
+}
+
+public enum LegacyRuntimeStockCutMenuSource
+{
+    ExternalOverride,
+    Packaged,
+    BuiltIn
+}
+
+public sealed record LegacyRuntimeStockCutMenuComposition(
+    IReadOnlyList<LegacyCutCatalogRow> Rows,
+    LegacyRuntimeStockCutMenuSource Source,
+    LegacyRuntimeStockCutMenuFailure Failure,
+    string? WarningMessage)
+{
+    public bool UsesBuiltInCatalog => Source == LegacyRuntimeStockCutMenuSource.BuiltIn;
+}
+
+public static class LegacyRuntimeStockCutMenuLoader
+{
+    public const int MaximumRows = 50;
+    public const int MaximumFileBytes = 64 * 1024;
+    public const string StockSectionHeader = "[종목]";
+    public const string FallbackWarningMessage =
+        "런타임 컷 메뉴를 읽지 못해 내장 컷 목록을 사용합니다.";
+
+    private static readonly Encoding Cp949 = CreateCp949Encoding();
+    private static readonly HashSet<string> KnownCutLabels = LegacyStockCutCatalog.Rows
+        .Where(row => !row.IsSeparator)
+        .Select(row => row.RawLabel)
+        .ToHashSet(StringComparer.Ordinal);
+
+    public static LegacyRuntimeStockCutMenuComposition ResolveFromBaseDirectory(
+        string? baseDirectory)
+    {
+        if (!TryCreatePackagedCandidatePath(baseDirectory, out var path))
+        {
+            return CreateFallbackComposition(
+                LegacyRuntimeStockCutMenuFailure.InvalidPath);
+        }
+
+        if (TryLoad(path, out var rows, out var failure))
+        {
+            return CreateRuntimeComposition(
+                rows,
+                LegacyRuntimeStockCutMenuSource.Packaged);
+        }
+
+        return CreateFallbackComposition(failure);
+    }
+
+    public static LegacyRuntimeStockCutMenuComposition ResolveFromCandidates(
+        string? externalOverridePath,
+        string? packagedBaseDirectory)
+    {
+        if (externalOverridePath is not null)
+        {
+            if (!TryNormalizeExternalOverridePath(
+                    externalOverridePath,
+                    out var normalizedExternalPath))
+            {
+                return CreateFallbackComposition(
+                    LegacyRuntimeStockCutMenuFailure.InvalidPath);
+            }
+
+            if (TryLoad(
+                    normalizedExternalPath,
+                    out var externalRows,
+                    out var externalFailure))
+            {
+                return CreateRuntimeComposition(
+                    externalRows,
+                    LegacyRuntimeStockCutMenuSource.ExternalOverride);
+            }
+
+            if (externalFailure != LegacyRuntimeStockCutMenuFailure.FileNotFound)
+            {
+                return CreateFallbackComposition(externalFailure);
+            }
+        }
+
+        return ResolveFromBaseDirectory(packagedBaseDirectory);
+    }
+
+    public static bool TryLoad(
+        string? path,
+        out IReadOnlyList<LegacyCutCatalogRow> rows,
+        out LegacyRuntimeStockCutMenuFailure failure)
+    {
+        rows = Array.Empty<LegacyCutCatalogRow>();
+        if (string.IsNullOrWhiteSpace(path) ||
+            path.Any(char.IsControl) ||
+            !Path.IsPathFullyQualified(path))
+        {
+            failure = LegacyRuntimeStockCutMenuFailure.InvalidPath;
+            return false;
+        }
+
+        try
+        {
+            using var stream = new FileStream(
+                path,
+                FileMode.Open,
+                FileAccess.Read,
+                FileShare.Read,
+                bufferSize: 4096,
+                FileOptions.SequentialScan);
+            if (stream.Length > MaximumFileBytes)
+            {
+                failure = LegacyRuntimeStockCutMenuFailure.FileTooLarge;
+                return false;
+            }
+
+            var bytes = new byte[(int)stream.Length];
+            stream.ReadExactly(bytes);
+            return TryParse(bytes, out rows, out failure);
+        }
+        catch (Exception exception) when (
+            exception is FileNotFoundException or
+            DirectoryNotFoundException)
+        {
+            failure = LegacyRuntimeStockCutMenuFailure.FileNotFound;
+            return false;
+        }
+        catch (Exception exception) when (
+            exception is IOException or
+            UnauthorizedAccessException or
+            NotSupportedException or
+            ArgumentException or
+            System.Security.SecurityException)
+        {
+            failure = LegacyRuntimeStockCutMenuFailure.FileUnavailable;
+            return false;
+        }
+    }
+
+    public static bool TryParse(
+        ReadOnlySpan<byte> cp949Bytes,
+        out IReadOnlyList<LegacyCutCatalogRow> rows,
+        out LegacyRuntimeStockCutMenuFailure failure)
+    {
+        rows = Array.Empty<LegacyCutCatalogRow>();
+        if (cp949Bytes.Length > MaximumFileBytes)
+        {
+            failure = LegacyRuntimeStockCutMenuFailure.FileTooLarge;
+            return false;
+        }
+
+        string text;
+        try
+        {
+            text = Cp949.GetString(cp949Bytes);
+        }
+        catch (DecoderFallbackException)
+        {
+            failure = LegacyRuntimeStockCutMenuFailure.InvalidEncoding;
+            return false;
+        }
+
+        return TryParseDecodedText(text, out rows, out failure);
+    }
+
+    private static bool TryParseDecodedText(
+        string text,
+        out IReadOnlyList<LegacyCutCatalogRow> rows,
+        out LegacyRuntimeStockCutMenuFailure failure)
+    {
+        rows = Array.Empty<LegacyCutCatalogRow>();
+        var parsedRows = new List<LegacyCutCatalogRow>();
+        var sawSection = false;
+        var displayOrdinal = 0;
+
+        using var reader = new StringReader(text);
+        while (reader.ReadLine() is { } sourceLine)
+        {
+            var line = sourceLine.Trim();
+            if (line.Length == 0)
+            {
+                continue;
+            }
+
+            if (!sawSection)
+            {
+                if (!string.Equals(line, StockSectionHeader, StringComparison.Ordinal))
+                {
+                    failure = LegacyRuntimeStockCutMenuFailure.InvalidFormat;
+                    return false;
+                }
+
+                sawSection = true;
+                continue;
+            }
+
+            if (line.StartsWith("[", StringComparison.Ordinal))
+            {
+                failure = LegacyRuntimeStockCutMenuFailure.InvalidFormat;
+                return false;
+            }
+
+            if (parsedRows.Count >= MaximumRows)
+            {
+                failure = LegacyRuntimeStockCutMenuFailure.TooManyRows;
+                return false;
+            }
+
+            var isSeparator = string.Equals(line, "-", StringComparison.Ordinal);
+            if (!isSeparator && !KnownCutLabels.Contains(line))
+            {
+                failure = LegacyRuntimeStockCutMenuFailure.UnknownCut;
+                return false;
+            }
+
+            parsedRows.Add(new LegacyCutCatalogRow(
+                parsedRows.Count,
+                isSeparator ? null : ++displayOrdinal,
+                isSeparator ? string.Empty : line,
+                isSeparator));
+        }
+
+        if (!sawSection)
+        {
+            failure = LegacyRuntimeStockCutMenuFailure.InvalidFormat;
+            return false;
+        }
+
+        if (displayOrdinal == 0)
+        {
+            failure = LegacyRuntimeStockCutMenuFailure.EmptyMenu;
+            return false;
+        }
+
+        rows = parsedRows.AsReadOnly();
+        failure = LegacyRuntimeStockCutMenuFailure.None;
+        return true;
+    }
+
+    private static Encoding CreateCp949Encoding()
+    {
+        Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
+        return Encoding.GetEncoding(
+            949,
+            EncoderFallback.ExceptionFallback,
+            DecoderFallback.ExceptionFallback);
+    }
+
+    private static LegacyRuntimeStockCutMenuComposition CreateFallbackComposition(
+        LegacyRuntimeStockCutMenuFailure failure) =>
+        new(
+            LegacyStockCutCatalog.Rows,
+            LegacyRuntimeStockCutMenuSource.BuiltIn,
+            failure,
+            FallbackWarningMessage);
+
+    private static LegacyRuntimeStockCutMenuComposition CreateRuntimeComposition(
+        IReadOnlyList<LegacyCutCatalogRow> rows,
+        LegacyRuntimeStockCutMenuSource source) =>
+        new(
+            rows,
+            source,
+            LegacyRuntimeStockCutMenuFailure.None,
+            WarningMessage: null);
+
+    private static bool TryCreatePackagedCandidatePath(
+        string? baseDirectory,
+        out string path)
+    {
+        path = string.Empty;
+        if (string.IsNullOrWhiteSpace(baseDirectory) ||
+            baseDirectory.Any(char.IsControl) ||
+            !Path.IsPathFullyQualified(baseDirectory))
+        {
+            return false;
+        }
+
+        try
+        {
+            path = Path.Combine(
+                Path.GetFullPath(baseDirectory),
+                "Res",
+                "종목.ini");
+            return true;
+        }
+        catch (Exception exception) when (
+            exception is ArgumentException or
+            IOException or
+            NotSupportedException or
+            System.Security.SecurityException)
+        {
+            return false;
+        }
+    }
+
+    private static bool TryNormalizeExternalOverridePath(
+        string path,
+        out string normalizedPath)
+    {
+        normalizedPath = string.Empty;
+        if (string.IsNullOrWhiteSpace(path) ||
+            path.Any(char.IsControl) ||
+            !Path.IsPathFullyQualified(path))
+        {
+            return false;
+        }
+
+        try
+        {
+            normalizedPath = Path.GetFullPath(path);
+            var resourceDirectory = Path.GetDirectoryName(normalizedPath);
+            var applicationDirectory = resourceDirectory is null
+                ? null
+                : Path.GetDirectoryName(resourceDirectory);
+            return string.Equals(
+                    Path.GetFileName(normalizedPath),
+                    "종목.ini",
+                    StringComparison.OrdinalIgnoreCase) &&
+                string.Equals(
+                    resourceDirectory is null
+                        ? null
+                        : Path.GetFileName(resourceDirectory),
+                    "Res",
+                    StringComparison.OrdinalIgnoreCase) &&
+                string.Equals(
+                    applicationDirectory is null
+                        ? null
+                        : Path.GetFileName(applicationDirectory),
+                    "MBN_STOCK_WEBVIEW",
+                    StringComparison.OrdinalIgnoreCase);
+        }
+        catch (Exception exception) when (
+            exception is ArgumentException or
+            IOException or
+            NotSupportedException or
+            System.Security.SecurityException)
+        {
+            normalizedPath = string.Empty;
+            return false;
+        }
+    }
+}

src/MBN_STOCK_WEBVIEW.LegacyApplication/LegacyStockCutCatalog.cs

@@ -1,3 +1,4 @@
+using MBN_STOCK_WEBVIEW.Core.Playout;
 using MBN_STOCK_WEBVIEW.Core.Playout.Scenes;
 
 namespace MBN_STOCK_WEBVIEW.LegacyApplication;
@@ -21,7 +22,8 @@ public sealed record LegacyOperatorPlaylistRow(
     int FadeDuration,
     bool IsSelected = false,
     string SceneAlias = "",
-    LegacySceneSelection? PlayoutSelection = null)
+    LegacySceneSelection? PlayoutSelection = null,
+    bool IsActive = false)
 {
     public LegacyPlaylistEntry ToPlayoutEntry()
     {
@@ -40,7 +42,47 @@ public sealed record LegacyOperatorPlaylistRow(
                 StockName,
                 GraphicType,
                 Subtype,
-                StockCode));
+                StockCode),
+            CreatePageNavigation());
+    }
+
+    private LegacyPlaylistPageNavigation CreatePageNavigation()
+    {
+        var pageSize = GraphicType switch
+        {
+            "5단 표그래프" => ScenePageSize.Five,
+            "6종목 현재가" => ScenePageSize.Six,
+            "12종목 현재가" => ScenePageSize.Twelve,
+            _ => (ScenePageSize?)null
+        };
+        if (!pageSize.HasValue)
+        {
+            // MainForm's PageN branches compared the visible FarPoint column text
+            // exactly. A scene alias that happens to resolve to a paged builder is still
+            // an ordinary playlist row when that column uses any other spelling.
+            return LegacyPlaylistPageNavigation.Disabled;
+        }
+
+        var separator = PageText.IndexOf('/');
+        if (separator <= 0 || separator != PageText.LastIndexOf('/') ||
+            !int.TryParse(
+                PageText.AsSpan(0, separator),
+                System.Globalization.NumberStyles.None,
+                System.Globalization.CultureInfo.InvariantCulture,
+                out var currentPage) ||
+            !int.TryParse(
+                PageText.AsSpan(separator + 1),
+                System.Globalization.NumberStyles.None,
+                System.Globalization.CultureInfo.InvariantCulture,
+                out var totalPages) ||
+            totalPages is < 1 or > ScenePaging.MaximumPageCount ||
+            currentPage < 1 || currentPage > totalPages)
+        {
+            throw new InvalidOperationException(
+                "A PageN playlist row must use current/total with a total from 1 through 20.");
+        }
+
+        return new LegacyPlaylistPageNavigation(pageSize, totalPages);
     }
 }
 

src/MBN_STOCK_WEBVIEW.LegacyApplication/TradingHalt/LegacyTradingHaltWorkflow.cs

@@ -119,6 +119,33 @@ public sealed class LegacyTradingHaltWorkflowController
         }
     }
 
+    /// <summary>
+    /// Recreates UC7's per-control query, result, selection and column-sort state.
+    /// MainForm-owned moving-average values remain in force across tab activation.
+    /// </summary>
+    public LegacyTradingHaltWorkflowSnapshot ResetForTabActivation()
+    {
+        lock (_gate)
+        {
+            checked
+            {
+                _searchGeneration++;
+            }
+
+            _results = [];
+            _selected = null;
+            _query = string.Empty;
+            _errorMessage = string.Empty;
+            _statusMessage = string.Empty;
+            _status = LegacyTradingHaltRequestStatus.Idle;
+            _nameSort = LegacyTradingHaltNameSort.None;
+            _statusKind = LegacyOperatorStatusKind.Neutral;
+            _isTruncated = false;
+            Touch();
+            return CreateSnapshot();
+        }
+    }
+
     public async Task<LegacyTradingHaltWorkflowSnapshot> SearchAsync(
         string query,
         CancellationToken cancellationToken = default)