From fe4d5a076ca49396dfb22baf131ecfb137151b1d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ng=C3=B4=20Qu=E1=BB=91c=20=C4=90=E1=BA=A1t?=
 <datlechin@gmail.com>
Date: Tue, 31 Mar 2026 11:13:16 +0700
Subject: [PATCH 1/2] perf: optimize DataGridView scroll by pre-computing
 column metadata and warming display cache

---
 TablePro/Models/Query/RowProvider.swift       | 17 ++++++++++++
 .../Views/Results/DataGridCellFactory.swift   |  3 +--
 .../Views/Results/DataGridCoordinator.swift   | 26 +++++++++++++++++++
 TablePro/Views/Results/DataGridView.swift     |  8 ++++++
 .../Extensions/DataGridView+Columns.swift     | 16 ++----------
 5 files changed, 54 insertions(+), 16 deletions(-)

diff --git a/TablePro/Models/Query/RowProvider.swift b/TablePro/Models/Query/RowProvider.swift
index 2a81e1a1d..8af31183b 100644
--- a/TablePro/Models/Query/RowProvider.swift
+++ b/TablePro/Models/Query/RowProvider.swift
@@ -217,6 +217,23 @@ final class InMemoryRowProvider: RowProvider {
         return columnIndex < rowCache.count ? rowCache[columnIndex] : nil
     }
 
+    @MainActor
+    func preWarmDisplayCache(upTo rowCount: Int) {
+        let count = min(rowCount, totalRowCount)
+        for row in 0..<count {
+            let cacheKey = resolveCacheKey(for: row)
+            guard displayCache[cacheKey] == nil else { continue }
+            let src = sourceRow(at: row)
+            let columnCount = columns.count
+            var rowCache = [String?](repeating: nil, count: columnCount)
+            for col in 0..<min(src.count, columnCount) {
+                let ct = col < columnTypes.count ? columnTypes[col] : nil
+                rowCache[col] = CellDisplayFormatter.format(src[col], columnType: ct)
+            }
+            displayCache[cacheKey] = rowCache
+        }
+    }
+
     /// Invalidate entire display cache (after settings change, full reload).
     func invalidateDisplayCache() {
         displayCache.removeAll()
diff --git a/TablePro/Views/Results/DataGridCellFactory.swift b/TablePro/Views/Results/DataGridCellFactory.swift
index 6c402e661..d47c80913 100644
--- a/TablePro/Views/Results/DataGridCellFactory.swift
+++ b/TablePro/Views/Results/DataGridCellFactory.swift
@@ -230,8 +230,7 @@ final class DataGridCellFactory {
             isNewCell = true
         }
 
-        // Re-apply single-line properties (editing may reset these on reused cells)
-        if !isNewCell {
+        if !isNewCell && cell.lineBreakMode != .byTruncatingTail {
             cell.lineBreakMode = .byTruncatingTail
             cell.maximumNumberOfLines = 1
             cell.cell?.truncatesLastVisibleLine = true
diff --git a/TablePro/Views/Results/DataGridCoordinator.swift b/TablePro/Views/Results/DataGridCoordinator.swift
index 827b159d7..c98464e71 100644
--- a/TablePro/Views/Results/DataGridCoordinator.swift
+++ b/TablePro/Views/Results/DataGridCoordinator.swift
@@ -95,6 +95,8 @@ final class TableViewCoordinator: NSObject, NSTableViewDelegate, NSTableViewData
     var lastReapplyVersion: Int = -1
     private(set) var cachedRowCount: Int = 0
     private(set) var cachedColumnCount: Int = 0
+    private(set) var enumOrSetColumns: Set<Int> = []
+    private(set) var fkColumns: Set<Int> = []
     var isSyncingSortDescriptors: Bool = false
     /// Suppresses selection delegate callbacks during programmatic selection sync
     var isSyncingSelection = false
@@ -263,6 +265,30 @@ final class TableViewCoordinator: NSObject, NSTableViewDelegate, NSTableViewData
         cachedColumnCount = rowProvider.columns.count
     }
 
+    func rebuildColumnMetadataCache() {
+        var enumSet = Set<Int>()
+        var fkSet = Set<Int>()
+        let columns = rowProvider.columns
+        let types = rowProvider.columnTypes
+        let enumValues = rowProvider.columnEnumValues
+        let fkKeys = rowProvider.columnForeignKeys
+
+        for i in 0..<columns.count {
+            let name = columns[i]
+            if i < types.count {
+                let ct = types[i]
+                if (ct.isEnumType || ct.isSetType) && enumValues[name]?.isEmpty == false {
+                    enumSet.insert(i)
+                }
+            }
+            if fkKeys[name] != nil {
+                fkSet.insert(i)
+            }
+        }
+        enumOrSetColumns = enumSet
+        fkColumns = fkSet
+    }
+
     // MARK: - Font Updates
 
     /// Update fonts on existing visible cell views in-place.
diff --git a/TablePro/Views/Results/DataGridView.swift b/TablePro/Views/Results/DataGridView.swift
index ad28f3dcf..a6216221c 100644
--- a/TablePro/Views/Results/DataGridView.swift
+++ b/TablePro/Views/Results/DataGridView.swift
@@ -174,6 +174,7 @@ struct DataGridView: NSViewRepresentable {
         scrollView.documentView = tableView
         context.coordinator.tableView = tableView
         context.coordinator.onMoveRow = onMoveRow
+        context.coordinator.rebuildColumnMetadataCache()
         if let connectionId {
             context.coordinator.observeTeardown(connectionId: connectionId)
         }
@@ -280,6 +281,13 @@ struct DataGridView: NSViewRepresentable {
         }
 
         coordinator.updateCache()
+        coordinator.rebuildColumnMetadataCache()
+
+        if previousIdentity == nil || previousIdentity?.rowCount == 0 {
+            let visibleRows = Int(tableView.visibleRect.height / tableView.rowHeight) + 5
+            coordinator.rowProvider.preWarmDisplayCache(upTo: visibleRows)
+        }
+
         coordinator.changeManager = changeManager
         coordinator.isEditable = isEditable
         coordinator.onRefresh = onRefresh
diff --git a/TablePro/Views/Results/Extensions/DataGridView+Columns.swift b/TablePro/Views/Results/Extensions/DataGridView+Columns.swift
index f8f61ffd9..7a6b6851c 100644
--- a/TablePro/Views/Results/Extensions/DataGridView+Columns.swift
+++ b/TablePro/Views/Results/Extensions/DataGridView+Columns.swift
@@ -43,20 +43,8 @@ extension TableViewCoordinator {
         let isDropdown = dropdownColumns?.contains(columnIndex) == true
         let isTypePicker = typePickerColumns?.contains(columnIndex) == true
 
-        let isEnumOrSet: Bool = {
-            guard columnIndex < rowProvider.columnTypes.count,
-                  columnIndex < rowProvider.columns.count else { return false }
-            let ct = rowProvider.columnTypes[columnIndex]
-            let columnName = rowProvider.columns[columnIndex]
-            guard ct.isEnumType || ct.isSetType else { return false }
-            return rowProvider.columnEnumValues[columnName]?.isEmpty == false
-        }()
-
-        let isFKColumn: Bool = {
-            guard columnIndex < rowProvider.columns.count else { return false }
-            let columnName = rowProvider.columns[columnIndex]
-            return rowProvider.columnForeignKeys[columnName] != nil
-        }()
+        let isEnumOrSet = enumOrSetColumns.contains(columnIndex)
+        let isFKColumn = fkColumns.contains(columnIndex)
 
         return cellFactory.makeDataCell(
             tableView: tableView,

From c8f122e3eed8382c7af741f31d1e6cd3699f964b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ng=C3=B4=20Qu=E1=BB=91c=20=C4=90=E1=BA=A1t?=
 <datlechin@gmail.com>
Date: Tue, 31 Mar 2026 11:17:01 +0700
Subject: [PATCH 2/2] =?UTF-8?q?fix:=20address=20review=20=E2=80=94=20compl?=
 =?UTF-8?q?ete=20cell=20property=20guard,=20prevent=20division=20by=20zero?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 TablePro/Views/Results/DataGridCellFactory.swift | 7 ++++++-
 TablePro/Views/Results/DataGridView.swift        | 7 +++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/TablePro/Views/Results/DataGridCellFactory.swift b/TablePro/Views/Results/DataGridCellFactory.swift
index d47c80913..a7f25b687 100644
--- a/TablePro/Views/Results/DataGridCellFactory.swift
+++ b/TablePro/Views/Results/DataGridCellFactory.swift
@@ -230,7 +230,12 @@ final class DataGridCellFactory {
             isNewCell = true
         }
 
-        if !isNewCell && cell.lineBreakMode != .byTruncatingTail {
+        if !isNewCell && (
+            cell.lineBreakMode != .byTruncatingTail ||
+            cell.maximumNumberOfLines != 1 ||
+            cell.cell?.truncatesLastVisibleLine != true ||
+            cell.cell?.usesSingleLineMode != true
+        ) {
             cell.lineBreakMode = .byTruncatingTail
             cell.maximumNumberOfLines = 1
             cell.cell?.truncatesLastVisibleLine = true
diff --git a/TablePro/Views/Results/DataGridView.swift b/TablePro/Views/Results/DataGridView.swift
index a6216221c..02d6d0e3c 100644
--- a/TablePro/Views/Results/DataGridView.swift
+++ b/TablePro/Views/Results/DataGridView.swift
@@ -284,8 +284,11 @@ struct DataGridView: NSViewRepresentable {
         coordinator.rebuildColumnMetadataCache()
 
         if previousIdentity == nil || previousIdentity?.rowCount == 0 {
-            let visibleRows = Int(tableView.visibleRect.height / tableView.rowHeight) + 5
-            coordinator.rowProvider.preWarmDisplayCache(upTo: visibleRows)
+            let rowH = tableView.rowHeight
+            if rowH > 0 {
+                let visibleRows = Int(tableView.visibleRect.height / rowH) + 5
+                coordinator.rowProvider.preWarmDisplayCache(upTo: visibleRows)
+            }
         }
 
         coordinator.changeManager = changeManager