fix(tui): stabilize full-width layout and sparkline rendering

1 files changed, 22 insertions, 0 deletions

diff --git a/internal/tui/common/viewport.go b/internal/tui/common/viewport.go
index 099a4e1..d54c886 100644
--- a/internal/tui/common/viewport.go
+++ b/internal/tui/common/viewport.go
@@ -1,13 +1,35 @@
 package common
 
+import (
+	"os"
+
+	xterm "github.com/charmbracelet/x/term"
+)
+
 const (
 	defaultViewportWidth  = 80
 	defaultViewportHeight = 24
 )
 
+var queryTerminalSize = func() (int, int, error) {
+	return xterm.GetSize(os.Stdout.Fd())
+}
+
 // EffectiveViewport returns a usable terminal viewport size. Missing or invalid
 // dimensions fall back to defaults.
 func EffectiveViewport(width, height int) (int, int) {
+	if width <= 0 || height <= 0 {
+		terminalWidth, terminalHeight, err := queryTerminalSize()
+		if err == nil {
+			if width <= 0 && terminalWidth > 0 {
+				width = terminalWidth
+			}
+			if height <= 0 && terminalHeight > 0 {
+				height = terminalHeight
+			}
+		}
+	}
+
 	if width <= 0 {
 		width = defaultViewportWidth
 	}