From 5a32d79d81550f2d41447f452e0278d212defeee Mon Sep 17 00:00:00 2001
From: roboomp <omp@can.ac>
Date: Tue, 14 Jul 2026 19:55:16 +0000
Subject: [PATCH] fix(tui): stop PageUp/PageDown stepping prompt history at
 idle

PageUp/PageDown on an empty editor aliased to prompt-history navigation, identical to Up/Down, so idle page keys loaded the previous prompt instead of paging. They now only page the editor viewport (a no-op on a short draft) and never touch prompt history.

Fixes #4754
---
 packages/tui/CHANGELOG.md             |  4 ++++
 packages/tui/src/components/editor.ts | 19 ++++++-------------
 packages/tui/test/editor.test.ts      | 21 +++++++++++++++++++++
 3 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/packages/tui/CHANGELOG.md b/packages/tui/CHANGELOG.md
index b6d4864c9..dd0c4c178 100644
--- a/packages/tui/CHANGELOG.md
+++ b/packages/tui/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed PageUp/PageDown on an idle (empty) prompt editor stepping through prompt history like the Up/Down arrows instead of paging the draft. The paging keys now only scroll the editor viewport (a no-op on a short draft) and never touch prompt history ([#4754](https://github.com/can1357/oh-my-pi/issues/4754)).
+
 ## [16.3.10] - 2026-07-06
 
 ### Fixed
diff --git a/packages/tui/src/components/editor.ts b/packages/tui/src/components/editor.ts
index 8a631d790..312a78d6f 100644
--- a/packages/tui/src/components/editor.ts
+++ b/packages/tui/src/components/editor.ts
@@ -1357,21 +1357,14 @@ export class Editor implements Component, Focusable {
 		} else if (kb.matches(data, "tui.editor.cursorLineEnd")) {
 			this.#moveToLineEnd();
 		}
-		// Page navigation (PageUp/PageDown)
+		// Page navigation (PageUp/PageDown): page the editor viewport only. On a
+		// short draft this is a no-op — it never steps prompt history (that stays
+		// on Up/Down), so an idle empty editor swallows the keys instead of
+		// surprising the user by loading the previous prompt (#4754).
 		else if (kb.matches(data, "tui.editor.pageUp")) {
-			if (this.#isEditorEmpty()) {
-				this.#navigateHistory(-1);
-			} else if (this.#historyIndex > -1 && this.#isOnFirstVisualLine()) {
-				this.#navigateHistory(-1);
-			} else {
-				this.#pageScroll(-1);
-			}
+			this.#pageScroll(-1);
 		} else if (kb.matches(data, "tui.editor.pageDown")) {
-			if (this.#historyIndex > -1 && this.#isOnLastVisualLine()) {
-				this.#navigateHistory(1);
-			} else {
-				this.#pageScroll(1);
-			}
+			this.#pageScroll(1);
 		}
 		// Forward delete (Fn+Backspace or Delete key, including Shift+Delete)
 		else if (kb.matches(data, "tui.editor.deleteCharForward") || matchesKey(data, "shift+delete")) {
diff --git a/packages/tui/test/editor.test.ts b/packages/tui/test/editor.test.ts
index d451c758e..278f391b9 100644
--- a/packages/tui/test/editor.test.ts
+++ b/packages/tui/test/editor.test.ts
@@ -1936,6 +1936,27 @@ describe("Editor component", () => {
 			expect(editor.getCursor()).toEqual({ line: 6, col: 2 });
 		});
 
+		it("PageUp/PageDown on an idle editor never step prompt history (#4754)", () => {
+			const editor = new Editor(defaultEditorTheme);
+
+			editor.addToHistory("first prompt");
+			editor.addToHistory("second prompt");
+			editor.render(80);
+			expect(editor.getText()).toBe("");
+
+			editor.handleInput("\x1b[5~"); // PageUp on empty editor
+			expect(editor.getText()).toBe("");
+
+			editor.handleInput("\x1b[6~"); // PageDown on empty editor
+			expect(editor.getText()).toBe("");
+
+			// While browsing history (entered via Up), PageUp must not advance it.
+			editor.handleInput("\x1b[A"); // Up - shows "second prompt"
+			expect(editor.getText()).toBe("second prompt");
+			editor.handleInput("\x1b[5~"); // PageUp - stays put
+			expect(editor.getText()).toBe("second prompt");
+		});
+
 		it("moves correctly through wrapped visual lines without getting stuck", () => {
 			const editor = new Editor(defaultEditorTheme);