func()

in winterm/win_event_handler.go [447:504]

• 42 lines of code
• 10 McCabe index (conditional complexity)

func (h *windowsAnsiEventHandler) ED(param int) error {
	if err := h.Flush(); err != nil {
		return err
	}
	h.logf("ED: [%v]", []string{strconv.Itoa(param)})
	h.clearWrap()

	// [J  -- Erases from the cursor to the end of the screen, including the cursor position.
	// [1J -- Erases from the beginning of the screen to the cursor, including the cursor position.
	// [2J -- Erases the complete display. The cursor does not move.
	// Notes:
	// -- Clearing the entire buffer, versus just the Window, works best for Windows Consoles

	info, err := GetConsoleScreenBufferInfo(h.fd)
	if err != nil {
		return err
	}

	var start COORD
	var end COORD

	switch param {
	case 0:
		start = info.CursorPosition
		end = COORD{info.Size.X - 1, info.Size.Y - 1}

	case 1:
		start = COORD{0, 0}
		end = info.CursorPosition

	case 2:
		start = COORD{0, 0}
		end = COORD{info.Size.X - 1, info.Size.Y - 1}
	}

	err = h.clearRange(h.attributes, start, end)
	if err != nil {
		return err
	}

	// If the whole buffer was cleared, move the window to the top while preserving
	// the window-relative cursor position.
	if param == 2 {
		pos := info.CursorPosition
		window := info.Window
		pos.Y -= window.Top
		window.Bottom -= window.Top
		window.Top = 0
		if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
			return err
		}
		if err := SetConsoleWindowInfo(h.fd, true, window); err != nil {
			return err
		}
	}

	return nil
}