From 42b802b688f92e7077c5a828df4c62296c326bbf Mon Sep 17 00:00:00 2001
From: adamelmore <2363879+adamdottv@users.noreply.github.com>
Date: Sat, 24 Jan 2026 12:19:39 -0600
Subject: [PATCH] fix(app): line selection ux fixes

---
 packages/ui/src/components/code.tsx           | 29 +++++++--------
 packages/ui/src/components/diff.tsx           | 37 +++++++++++++++++--
 packages/ui/src/components/line-comment.css   |  2 +-
 packages/ui/src/components/session-review.tsx |  2 +-
 packages/ui/src/pierre/index.ts               |  9 +++++
 5 files changed, 57 insertions(+), 22 deletions(-)

diff --git a/packages/ui/src/components/code.tsx b/packages/ui/src/components/code.tsx
index 16a915d9d..eb0ba7826 100644
--- a/packages/ui/src/components/code.tsx
+++ b/packages/ui/src/components/code.tsx
@@ -66,28 +66,16 @@ export function Code<T>(props: CodeProps<T>) {
     "selectedLines",
     "commentedLines",
     "onRendered",
-    "onLineSelectionEnd",
   ])
 
   const [rendered, setRendered] = createSignal(0)
 
-  const handleLineClick: FileOptions<T>["onLineClick"] = (info) => {
-    props.onLineClick?.(info)
-
-    if (props.enableLineSelection !== true) return
-    if (info.numberColumn) return
-    if (!local.selectedLines) return
-
-    file().setSelectedLines(null)
-  }
-
   const file = createMemo(
     () =>
       new File<T>(
         {
           ...createDefaultOptions<T>("unified"),
           ...others,
-          onLineClick: props.enableLineSelection === true || props.onLineClick ? handleLineClick : undefined,
         },
         getWorkerPool("unified"),
       ),
@@ -332,12 +320,21 @@ export function Code<T>(props: CodeProps<T>) {
     if (props.enableLineSelection !== true) return
     if (dragStart === undefined) return
 
-    if (dragMoved) {
-      pendingSelectionEnd = true
-      scheduleDragUpdate()
-      scheduleSelectionUpdate()
+    if (!dragMoved) {
+      pendingSelectionEnd = false
+      const line = dragStart
+      setSelectedLines({ start: line, end: line })
+      props.onLineSelectionEnd?.(lastSelection)
+      dragStart = undefined
+      dragEnd = undefined
+      dragMoved = false
+      return
     }
 
+    pendingSelectionEnd = true
+    scheduleDragUpdate()
+    scheduleSelectionUpdate()
+
     dragStart = undefined
     dragEnd = undefined
     dragMoved = false
diff --git a/packages/ui/src/components/diff.tsx b/packages/ui/src/components/diff.tsx
index 825a7e076..5aff93d1d 100644
--- a/packages/ui/src/components/diff.tsx
+++ b/packages/ui/src/components/diff.tsx
@@ -35,6 +35,13 @@ function findSide(node: Node | null): SelectionSide | undefined {
   const element = findElement(node)
   if (!element) return
 
+  const line = element.closest("[data-line], [data-alt-line]")
+  if (line instanceof HTMLElement) {
+    const type = line.dataset.lineType
+    if (type === "change-deletion") return "deletions"
+    if (type === "change-addition" || type === "change-additions") return "additions"
+  }
+
   const code = element.closest("[data-code]")
   if (!(code instanceof HTMLElement)) return
 
@@ -303,6 +310,12 @@ export function Diff<T>(props: DiffProps<T>) {
 
       numberColumn = numberColumn || item.dataset.columnNumber != null
 
+      if (side === undefined) {
+        const type = item.dataset.lineType
+        if (type === "change-deletion") side = "deletions"
+        if (type === "change-addition" || type === "change-additions") side = "additions"
+      }
+
       if (side === undefined && item.dataset.code != null) {
         side = item.hasAttribute("data-deletions") ? "deletions" : "additions"
       }
@@ -364,12 +377,28 @@ export function Diff<T>(props: DiffProps<T>) {
     if (props.enableLineSelection !== true) return
     if (dragStart === undefined) return
 
-    if (dragMoved) {
-      pendingSelectionEnd = true
-      scheduleDragUpdate()
-      scheduleSelectionUpdate()
+    if (!dragMoved) {
+      pendingSelectionEnd = false
+      const line = dragStart
+      const selected: SelectedLineRange = {
+        start: line,
+        end: line,
+      }
+      if (dragSide) selected.side = dragSide
+      setSelectedLines(selected)
+      props.onLineSelectionEnd?.(lastSelection)
+      dragStart = undefined
+      dragEnd = undefined
+      dragSide = undefined
+      dragEndSide = undefined
+      dragMoved = false
+      return
     }
 
+    pendingSelectionEnd = true
+    scheduleDragUpdate()
+    scheduleSelectionUpdate()
+
     dragStart = undefined
     dragEnd = undefined
     dragSide = undefined
diff --git a/packages/ui/src/components/line-comment.css b/packages/ui/src/components/line-comment.css
index 1cdf78189..d497f7fcd 100644
--- a/packages/ui/src/components/line-comment.css
+++ b/packages/ui/src/components/line-comment.css
@@ -13,7 +13,7 @@
   justify-content: center;
   background: var(--icon-interactive-base);
   box-shadow: var(--shadow-xs);
-  cursor: pointer;
+  cursor: default;
   border: none;
 }
 
diff --git a/packages/ui/src/components/session-review.tsx b/packages/ui/src/components/session-review.tsx
index 2b6d93e2d..1174cf2f3 100644
--- a/packages/ui/src/components/session-review.tsx
+++ b/packages/ui/src/components/session-review.tsx
@@ -618,7 +618,7 @@ export const SessionReview = (props: SessionReviewProps) => {
                                 />
                                 <div data-slot="session-review-comment-actions">
                                   <div data-slot="session-review-comment-draft-label">
-                                    Commenting on {getFilename(diff.file)}:{selectionLabel(range())}
+                                    Commenting on {selectionLabel(range())}
                                   </div>
                                   <Button size="small" variant="ghost" onClick={() => setCommenting(null)}>
                                     Cancel
diff --git a/packages/ui/src/pierre/index.ts b/packages/ui/src/pierre/index.ts
index cef515613..976f67eca 100644
--- a/packages/ui/src/pierre/index.ts
+++ b/packages/ui/src/pierre/index.ts
@@ -87,6 +87,15 @@ const unsafeCSS = `
   }
   [data-column-number] {
     background-color: var(--background-stronger);
+    cursor: default !important;
+  }
+
+  &[data-interactive-line-numbers] [data-column-number] {
+    cursor: default !important;
+  }
+
+  &[data-interactive-lines] [data-line] {
+    cursor: auto !important;
   }
   [data-code] {
     overflow-x: auto !important;