From e3bf513b1e2d99838fdc18de7d386a3e1aaaa6c3 Mon Sep 17 00:00:00 2001
From: Jin Ku <jin.ku@sendbird.com>
Date: Fri, 22 May 2026 09:56:55 -0700
Subject: [PATCH] Support Ctrl+Enter for sending messages

Treat terminal-reported Ctrl+Enter the same as plain Enter in insert mode so IME users have a native send chord that is less likely to be consumed as composition commit.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
---
 internal/ui/app.go      |  6 ++++--
 internal/ui/app_test.go | 38 ++++++++++++++++++++++++++++++++++++++
 wiki/Keybindings.md     |  2 +-
 3 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/internal/ui/app.go b/internal/ui/app.go
index e65bb953..f5ba85bb 100644
--- a/internal/ui/app.go
+++ b/internal/ui/app.go
@@ -3311,8 +3311,10 @@ func (a *App) handleInsertMode(msg tea.KeyMsg) tea.Cmd {
 			return nil
 		}
 	}
-	// Plain Enter sends; Shift+Enter (and Ctrl+J as a fallback for terminals
-	// that don't disambiguate modifiers) inserts a newline.
+	// Plain Enter sends. Ctrl+Enter also sends when the terminal reports it
+	// distinctly, which gives IME users a send key that is less likely to be
+	// consumed as composition commit. Shift+Enter (and Ctrl+J as a fallback for
+	// terminals that don't disambiguate modifiers) inserts a newline.
 	isSend := code == tea.KeyEnter && !mod.Contains(tea.ModShift)
 	isNewline := (code == tea.KeyEnter && mod.Contains(tea.ModShift)) ||
 		(code == 'j' && mod == tea.ModCtrl)
diff --git a/internal/ui/app_test.go b/internal/ui/app_test.go
index d70b825e..dcc8901d 100644
--- a/internal/ui/app_test.go
+++ b/internal/ui/app_test.go
@@ -303,6 +303,44 @@ func TestHandleInsertMode_PlainEnterSends(t *testing.T) {
 	}
 }
 
+func TestHandleInsertMode_CtrlEnterSends(t *testing.T) {
+	app := NewApp()
+	app.activeChannelID = "C1"
+	app.focusedPanel = PanelMessages
+	app.SetMode(ModeInsert)
+	app.compose.SetValue("hello")
+
+	cmd := app.handleInsertMode(tea.KeyPressMsg{Code: tea.KeyEnter, Mod: tea.ModCtrl})
+	if cmd == nil {
+		t.Fatalf("Ctrl+Enter with text should return a send cmd")
+	}
+	msg := cmd()
+	if _, ok := msg.(SendMessageMsg); !ok {
+		t.Fatalf("expected SendMessageMsg, got %T", msg)
+	}
+	if app.compose.Value() != "" {
+		t.Fatalf("expected compose to be reset after Ctrl+Enter send, got %q", app.compose.Value())
+	}
+}
+
+func TestHandleInsertMode_ThreadReplyCtrlEnterSends(t *testing.T) {
+	app := NewApp()
+	app.activeChannelID = "C1"
+	app.threadPanel.SetThread(messages.MessageItem{TS: "P1"}, nil, "C1", "P1")
+	app.threadVisible = true
+	app.focusedPanel = PanelThread
+	app.SetMode(ModeInsert)
+	app.threadCompose.SetValue("reply")
+
+	cmd := app.handleInsertMode(tea.KeyPressMsg{Code: tea.KeyEnter, Mod: tea.ModCtrl})
+	if cmd == nil {
+		t.Fatalf("Ctrl+Enter with thread text should return a send cmd")
+	}
+	if _, ok := cmd().(SendThreadReplyMsg); !ok {
+		t.Fatalf("expected SendThreadReplyMsg, got %T", cmd())
+	}
+}
+
 // TestHandleInsertMode_PlainEnterReturnsToNormalMode locks in the
 // vim-style UX: hitting Enter to submit a channel message drops the
 // user back to ModeNormal instead of leaving them in insert mode.
diff --git a/wiki/Keybindings.md b/wiki/Keybindings.md
index 4ebc111e..df062144 100644
--- a/wiki/Keybindings.md
+++ b/wiki/Keybindings.md
@@ -10,7 +10,7 @@
 | `Enter` | Normal (message) | Open thread |
 | `i` / `F2` | Normal | Enter insert mode (`F2` is useful when a CJK IME consumes alphabetic keys for composition) |
 | `Esc` | Insert / Command | Return to normal mode |
-| `Enter` | Insert | Send message |
+| `Enter` / `Ctrl+Enter` | Insert | Send message (`Ctrl+Enter` is useful when IME composition consumes plain Enter) |
 | `Shift+Enter` | Insert | Newline |
 | `Ctrl+V` | Insert | Smart paste — image / file path / text (use `Ctrl+V`, not the terminal's `Ctrl+Shift+V`) |
 | `Ctrl+U` | Insert | Clear compose (text + pending attachments) |