Limit cursor movement in detail views

ui/cursor/cursor.go

@@ -14,10 +14,14 @@ func Down(v View) error {
 		return nil
 	}
 	cx, cy := v.Cursor()
+	ox, oy := v.Origin()
 	_, _, sy, _ := v.Speed()
+	_, fs := v.Limits()
+	if cy+oy+sy >= fs {
+		return nil
+	}
 	err := v.SetCursor(cx, cy+sy)
 	if err != nil {
-		ox, oy := v.Origin()
 		err := v.SetOrigin(ox, oy+sy)
 		if err != nil {
 			return err

ui/views/channel.go

@@ -49,7 +49,9 @@ func (c Channel) Speed() (int, int, int, int) {
 }
 
 func (c Channel) Limits() (pageSize int, fullSize int) {
-	return 0, 0
+	_, pageSize = c.view.Size()
+	fullSize = len(c.view.BufferLines()) - 1
+	return
 }
 
 func (c *Channel) SetCursor(x, y int) error {

ui/views/help.go

@@ -43,7 +43,9 @@ func (h Help) Speed() (int, int, int, int) {
 }
 
 func (h Help) Limits() (pageSize int, fullSize int) {
-	return 0, 0
+	_, pageSize = h.view.Size()
+	fullSize = len(h.view.BufferLines()) - 1
+	return
 }
 
 func (h *Help) SetCursor(x, y int) error {

ui/views/routing.go

@@ -137,6 +137,9 @@ func (c *Routing) Speed() (int, int, int, int) {
 func (c *Routing) Limits() (pageSize int, fullSize int) {
 	_, pageSize = c.view.Size()
 	fullSize = len(c.routingEvents.Log)
+	if pageSize < fullSize {
+		fullSize = pageSize
+	}
 	return
 }
 

ui/views/transaction.go

@@ -48,7 +48,9 @@ func (c Transaction) Speed() (int, int, int, int) {
 }
 
 func (c Transaction) Limits() (pageSize int, fullSize int) {
-	return 0, 0
+	_, pageSize = c.view.Size()
+	fullSize = len(c.view.BufferLines()) - 1
+	return
 }
 
 func (c *Transaction) SetCursor(x, y int) error {