Vendor integration dependencies.

integration/vendor/github.com/Azure/go-ansiterm/winterm/scroll_helper.go

@@ -0,0 +1,118 @@
+// +build windows
+
+package winterm
+
+// effectiveSr gets the current effective scroll region in buffer coordinates
+func (h *windowsAnsiEventHandler) effectiveSr(window SMALL_RECT) scrollRegion {
+	top := addInRange(window.Top, h.sr.top, window.Top, window.Bottom)
+	bottom := addInRange(window.Top, h.sr.bottom, window.Top, window.Bottom)
+	if top >= bottom {
+		top = window.Top
+		bottom = window.Bottom
+	}
+	return scrollRegion{top: top, bottom: bottom}
+}
+
+func (h *windowsAnsiEventHandler) scrollUp(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	sr := h.effectiveSr(info.Window)
+	return h.scroll(param, sr, info)
+}
+
+func (h *windowsAnsiEventHandler) scrollDown(param int) error {
+	return h.scrollUp(-param)
+}
+
+func (h *windowsAnsiEventHandler) deleteLines(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	start := info.CursorPosition.Y
+	sr := h.effectiveSr(info.Window)
+	// Lines cannot be inserted or deleted outside the scrolling region.
+	if start >= sr.top && start <= sr.bottom {
+		sr.top = start
+		return h.scroll(param, sr, info)
+	} else {
+		return nil
+	}
+}
+
+func (h *windowsAnsiEventHandler) insertLines(param int) error {
+	return h.deleteLines(-param)
+}
+
+// scroll scrolls the provided scroll region by param lines. The scroll region is in buffer coordinates.
+func (h *windowsAnsiEventHandler) scroll(param int, sr scrollRegion, info *CONSOLE_SCREEN_BUFFER_INFO) error {
+	logger.Infof("scroll: scrollTop: %d, scrollBottom: %d", sr.top, sr.bottom)
+	logger.Infof("scroll: windowTop: %d, windowBottom: %d", info.Window.Top, info.Window.Bottom)
+
+	// Copy from and clip to the scroll region (full buffer width)
+	scrollRect := SMALL_RECT{
+		Top:    sr.top,
+		Bottom: sr.bottom,
+		Left:   0,
+		Right:  info.Size.X - 1,
+	}
+
+	// Origin to which area should be copied
+	destOrigin := COORD{
+		X: 0,
+		Y: sr.top - int16(param),
+	}
+
+	char := CHAR_INFO{
+		UnicodeChar: ' ',
+		Attributes:  h.attributes,
+	}
+
+	if err := ScrollConsoleScreenBuffer(h.fd, scrollRect, scrollRect, destOrigin, char); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) deleteCharacters(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+	return h.scrollLine(param, info.CursorPosition, info)
+}
+
+func (h *windowsAnsiEventHandler) insertCharacters(param int) error {
+	return h.deleteCharacters(-param)
+}
+
+// scrollLine scrolls a line horizontally starting at the provided position by a number of columns.
+func (h *windowsAnsiEventHandler) scrollLine(columns int, position COORD, info *CONSOLE_SCREEN_BUFFER_INFO) error {
+	// Copy from and clip to the scroll region (full buffer width)
+	scrollRect := SMALL_RECT{
+		Top:    position.Y,
+		Bottom: position.Y,
+		Left:   position.X,
+		Right:  info.Size.X - 1,
+	}
+
+	// Origin to which area should be copied
+	destOrigin := COORD{
+		X: position.X - int16(columns),
+		Y: position.Y,
+	}
+
+	char := CHAR_INFO{
+		UnicodeChar: ' ',
+		Attributes:  h.attributes,
+	}
+
+	if err := ScrollConsoleScreenBuffer(h.fd, scrollRect, scrollRect, destOrigin, char); err != nil {
+		return err
+	}
+	return nil
+}