// +build windows
package winterm
import (
"bytes"
"log"
"os"
"strconv"
"github.com/Azure/go-ansiterm"
)
type windowsAnsiEventHandler struct {
fd uintptr
file *os.File
infoReset *CONSOLE_SCREEN_BUFFER_INFO
sr scrollRegion
buffer bytes.Buffer
attributes uint16
inverted bool
wrapNext bool
drewMarginByte bool
originMode bool
marginByte byte
curInfo *CONSOLE_SCREEN_BUFFER_INFO
curPos COORD
logf func(string, ...interface{})
}
type Option func(*windowsAnsiEventHandler)
func WithLogf(f func(string, ...interface{})) Option {
return func(w *windowsAnsiEventHandler) {
w.logf = f
}
}
func CreateWinEventHandler(fd uintptr, file *os.File, opts ...Option) ansiterm.AnsiEventHandler {
infoReset, err := GetConsoleScreenBufferInfo(fd)
if err != nil {
return nil
}
h := &windowsAnsiEventHandler{
fd: fd,
file: file,
infoReset: infoReset,
attributes: infoReset.Attributes,
}
for _, o := range opts {
o(h)
}
if isDebugEnv := os.Getenv(ansiterm.LogEnv); isDebugEnv == "1" {
logFile, _ := os.Create("winEventHandler.log")
logger := log.New(logFile, "", log.LstdFlags)
if h.logf != nil {
l := h.logf
h.logf = func(s string, v ...interface{}) {
l(s, v...)
logger.Printf(s, v...)
}
} else {
h.logf = logger.Printf
}
}
if h.logf == nil {
h.logf = func(string, ...interface{}) {}
}
return h
}
type scrollRegion struct {
top int16
bottom int16
}
// simulateLF simulates a LF or CR+LF by scrolling if necessary to handle the
// current cursor position and scroll region settings, in which case it returns
// true. If no special handling is necessary, then it does nothing and returns
// false.
//
// In the false case, the caller should ensure that a carriage return
// and line feed are inserted or that the text is otherwise wrapped.
func (h *windowsAnsiEventHandler) simulateLF(includeCR bool) (bool, error) {
if h.wrapNext {
if err := h.Flush(); err != nil {
return false, err
}
h.clearWrap()
}
pos, info, err := h.getCurrentInfo()
if err != nil {
return false, err
}
sr := h.effectiveSr(info.Window)
if pos.Y == sr.bottom {
// Scrolling is necessary. Let Windows automatically scroll if the scrolling region
// is the full window.
if sr.top == info.Window.Top && sr.bottom == info.Window.Bottom {
if includeCR {
pos.X = 0
h.updatePos(pos)
}
return false, nil
}
// A custom scroll region is active. Scroll the window manually to simulate
// the LF.
if err := h.Flush(); err != nil {
return false, err
}
h.logf("Simulating LF inside scroll region")
if err := h.scrollUp(1); err != nil {
return false, err
}
if includeCR {
pos.X = 0
if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
return false, err
}
}
return true, nil
} else if pos.Y < info.Window.Bottom {
// Let Windows handle the LF.
pos.Y++
if includeCR {
pos.X = 0
}
h.updatePos(pos)
return false, nil
} else {
// The cursor is at the bottom of the screen but outside the scroll
// region. Skip the LF.
h.logf("Simulating LF outside scroll region")
if includeCR {
if err := h.Flush(); err != nil {
return false, err
}
pos.X = 0
if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
return false, err
}
}
return true, nil
}
}
// executeLF executes a LF without a CR.
func (h *windowsAnsiEventHandler) executeLF() error {
handled, err := h.simulateLF(false)
if err != nil {
return err
}
if !handled {
// Windows LF will reset the cursor column position. Write the LF
// and restore the cursor position.
pos, _, err := h.getCurrentInfo()
if err != nil {
return err
}
h.buffer.WriteByte(ansiterm.ANSI_LINE_FEED)
if pos.X != 0 {
if err := h.Flush(); err != nil {
return err
}
h.logf("Resetting cursor position for LF without CR")
if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
return err
}
}
}
return nil
}
func (h *windowsAnsiEventHandler) Print(b byte) error {
if h.wrapNext {
h.buffer.WriteByte(h.marginByte)
h.clearWrap()
if _, err := h.simulateLF(true); err != nil {
return err
}
}
pos, info, err := h.getCurrentInfo()
if err != nil {
return err
}
if pos.X == info.Size.X-1 {
h.wrapNext = true
h.marginByte = b
} else {
pos.X++
h.updatePos(pos)
h.buffer.WriteByte(b)
}
return nil
}
func (h *windowsAnsiEventHandler) Execute(b byte) error {
switch b {
case ansiterm.ANSI_TAB:
h.logf("Execute(TAB)")
// Move to the next tab stop, but preserve auto-wrap if already set.
if !h.wrapNext {
pos, info, err := h.getCurrentInfo()
if err != nil {
return err
}
pos.X = (pos.X + 8) - pos.X%8
if pos.X >= info.Size.X {
pos.X = info.Size.X - 1
}
if err := h.Flush(); err != nil {
return err
}
if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
return err
}
}
return nil
case ansiterm.ANSI_BEL:
h.buffer.WriteByte(ansiterm.ANSI_BEL)
return nil
case ansiterm.ANSI_BACKSPACE:
if h.wrapNext {
if err := h.Flush(); err != nil {
return err
}
h.clearWrap()
}
pos, _, err := h.getCurrentInfo()
if err != nil {
return err
}
if pos.X > 0 {
pos.X--
h.updatePos(pos)
h.buffer.WriteByte(ansiterm.ANSI_BACKSPACE)
}
return nil
case ansiterm.ANSI_VERTICAL_TAB, ansiterm.ANSI_FORM_FEED:
// Treat as true LF.
return h.executeLF()
case ansiterm.ANSI_LINE_FEED:
// Simulate a CR and LF for now since there is no way in go-ansiterm
// to tell if the LF should include CR (and more things break when it's
// missing than when it's incorrectly added).
handled, err := h.simulateLF(true)
if handled || err != nil {
return err
}
return h.buffer.WriteByte(ansiterm.ANSI_LINE_FEED)
case ansiterm.ANSI_CARRIAGE_RETURN:
if h.wrapNext {
if err := h.Flush(); err != nil {
return err
}
h.clearWrap()
}
pos, _, err := h.getCurrentInfo()
if err != nil {
return err
}
if pos.X != 0 {
pos.X = 0
h.updatePos(pos)
h.buffer.WriteByte(ansiterm.ANSI_CARRIAGE_RETURN)
}
return nil
default:
return nil
}
}
func (h *windowsAnsiEventHandler) CUU(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CUU: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.moveCursorVertical(-param)
}
func (h *windowsAnsiEventHandler) CUD(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CUD: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.moveCursorVertical(param)
}
func (h *windowsAnsiEventHandler) CUF(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CUF: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.moveCursorHorizontal(param)
}
func (h *windowsAnsiEventHandler) CUB(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CUB: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.moveCursorHorizontal(-param)
}
func (h *windowsAnsiEventHandler) CNL(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CNL: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.moveCursorLine(param)
}
func (h *windowsAnsiEventHandler) CPL(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CPL: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.moveCursorLine(-param)
}
func (h *windowsAnsiEventHandler) CHA(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CHA: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.moveCursorColumn(param)
}
func (h *windowsAnsiEventHandler) VPA(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("VPA: [[%d]]", param)
h.clearWrap()
info, err := GetConsoleScreenBufferInfo(h.fd)
if err != nil {
return err
}
window := h.getCursorWindow(info)
position := info.CursorPosition
position.Y = window.Top + int16(param) - 1
return h.setCursorPosition(position, window)
}
func (h *windowsAnsiEventHandler) CUP(row int, col int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("CUP: [[%d %d]]", row, col)
h.clearWrap()
info, err := GetConsoleScreenBufferInfo(h.fd)
if err != nil {
return err
}
window := h.getCursorWindow(info)
position := COORD{window.Left + int16(col) - 1, window.Top + int16(row) - 1}
return h.setCursorPosition(position, window)
}
func (h *windowsAnsiEventHandler) HVP(row int, col int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("HVP: [[%d %d]]", row, col)
h.clearWrap()
return h.CUP(row, col)
}
func (h *windowsAnsiEventHandler) DECTCEM(visible bool) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("DECTCEM: [%v]", []string{strconv.FormatBool(visible)})
h.clearWrap()
return nil
}
func (h *windowsAnsiEventHandler) DECOM(enable bool) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("DECOM: [%v]", []string{strconv.FormatBool(enable)})
h.clearWrap()
h.originMode = enable
return h.CUP(1, 1)
}
func (h *windowsAnsiEventHandler) DECCOLM(use132 bool) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("DECCOLM: [%v]", []string{strconv.FormatBool(use132)})
h.clearWrap()
if err := h.ED(2); err != nil {
return err
}
info, err := GetConsoleScreenBufferInfo(h.fd)
if err != nil {
return err
}
targetWidth := int16(80)
if use132 {
targetWidth = 132
}
if info.Size.X < targetWidth {
if err := SetConsoleScreenBufferSize(h.fd, COORD{targetWidth, info.Size.Y}); err != nil {
h.logf("set buffer failed: %v", err)
return err
}
}
window := info.Window
window.Left = 0
window.Right = targetWidth - 1
if err := SetConsoleWindowInfo(h.fd, true, window); err != nil {
h.logf("set window failed: %v", err)
return err
}
if info.Size.X > targetWidth {
if err := SetConsoleScreenBufferSize(h.fd, COORD{targetWidth, info.Size.Y}); err != nil {
h.logf("set buffer failed: %v", err)
return err
}
}
return SetConsoleCursorPosition(h.fd, COORD{0, 0})
}
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
}
func (h *windowsAnsiEventHandler) EL(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("EL: [%v]", strconv.Itoa(param))
h.clearWrap()
// [K -- Erases from the cursor to the end of the line, including the cursor position.
// [1K -- Erases from the beginning of the line to the cursor, including the cursor position.
// [2K -- Erases the complete line.
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, info.CursorPosition.Y}
case 1:
start = COORD{0, info.CursorPosition.Y}
end = info.CursorPosition
case 2:
start = COORD{0, info.CursorPosition.Y}
end = COORD{info.Size.X, info.CursorPosition.Y}
}
err = h.clearRange(h.attributes, start, end)
if err != nil {
return err
}
return nil
}
func (h *windowsAnsiEventHandler) IL(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("IL: [%v]", strconv.Itoa(param))
h.clearWrap()
return h.insertLines(param)
}
func (h *windowsAnsiEventHandler) DL(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("DL: [%v]", strconv.Itoa(param))
h.clearWrap()
return h.deleteLines(param)
}
func (h *windowsAnsiEventHandler) ICH(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("ICH: [%v]", strconv.Itoa(param))
h.clearWrap()
return h.insertCharacters(param)
}
func (h *windowsAnsiEventHandler) DCH(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("DCH: [%v]", strconv.Itoa(param))
h.clearWrap()
return h.deleteCharacters(param)
}
func (h *windowsAnsiEventHandler) SGR(params []int) error {
if err := h.Flush(); err != nil {
return err
}
strings := []string{}
for _, v := range params {
strings = append(strings, strconv.Itoa(v))
}
h.logf("SGR: [%v]", strings)
if len(params) <= 0 {
h.attributes = h.infoReset.Attributes
h.inverted = false
} else {
for _, attr := range params {
if attr == ansiterm.ANSI_SGR_RESET {
h.attributes = h.infoReset.Attributes
h.inverted = false
continue
}
h.attributes, h.inverted = collectAnsiIntoWindowsAttributes(h.attributes, h.inverted, h.infoReset.Attributes, int16(attr))
}
}
attributes := h.attributes
if h.inverted {
attributes = invertAttributes(attributes)
}
err := SetConsoleTextAttribute(h.fd, attributes)
if err != nil {
return err
}
return nil
}
func (h *windowsAnsiEventHandler) SU(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("SU: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.scrollUp(param)
}
func (h *windowsAnsiEventHandler) SD(param int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("SD: [%v]", []string{strconv.Itoa(param)})
h.clearWrap()
return h.scrollDown(param)
}
func (h *windowsAnsiEventHandler) DA(params []string) error {
h.logf("DA: [%v]", params)
// DA cannot be implemented because it must send data on the VT100 input stream,
// which is not available to go-ansiterm.
return nil
}
func (h *windowsAnsiEventHandler) DECSTBM(top int, bottom int) error {
if err := h.Flush(); err != nil {
return err
}
h.logf("DECSTBM: [%d, %d]", top, bottom)
// Windows is 0 indexed, Linux is 1 indexed
h.sr.top = int16(top - 1)
h.sr.bottom = int16(bottom - 1)
// This command also moves the cursor to the origin.
h.clearWrap()
return h.CUP(1, 1)
}
func (h *windowsAnsiEventHandler) RI() error {
if err := h.Flush(); err != nil {
return err
}
h.logf("RI: []")
h.clearWrap()
info, err := GetConsoleScreenBufferInfo(h.fd)
if err != nil {
return err
}
sr := h.effectiveSr(info.Window)
if info.CursorPosition.Y == sr.top {
return h.scrollDown(1)
}
return h.moveCursorVertical(-1)
}
func (h *windowsAnsiEventHandler) IND() error {
h.logf("IND: []")
return h.executeLF()
}
func (h *windowsAnsiEventHandler) Flush() error {
h.curInfo = nil
if h.buffer.Len() > 0 {
h.logf("Flush: [%s]", h.buffer.Bytes())
if _, err := h.buffer.WriteTo(h.file); err != nil {
return err
}
}
if h.wrapNext && !h.drewMarginByte {
h.logf("Flush: drawing margin byte '%c'", h.marginByte)
info, err := GetConsoleScreenBufferInfo(h.fd)
if err != nil {
return err
}
charInfo := []CHAR_INFO{{UnicodeChar: uint16(h.marginByte), Attributes: info.Attributes}}
size := COORD{1, 1}
position := COORD{0, 0}
region := SMALL_RECT{Left: info.CursorPosition.X, Top: info.CursorPosition.Y, Right: info.CursorPosition.X, Bottom: info.CursorPosition.Y}
if err := WriteConsoleOutput(h.fd, charInfo, size, position, ®ion); err != nil {
return err
}
h.drewMarginByte = true
}
return nil
}
// cacheConsoleInfo ensures that the current console screen information has been queried
// since the last call to Flush(). It must be called before accessing h.curInfo or h.curPos.
func (h *windowsAnsiEventHandler) getCurrentInfo() (COORD, *CONSOLE_SCREEN_BUFFER_INFO, error) {
if h.curInfo == nil {
info, err := GetConsoleScreenBufferInfo(h.fd)
if err != nil {
return COORD{}, nil, err
}
h.curInfo = info
h.curPos = info.CursorPosition
}
return h.curPos, h.curInfo, nil
}
func (h *windowsAnsiEventHandler) updatePos(pos COORD) {
if h.curInfo == nil {
panic("failed to call getCurrentInfo before calling updatePos")
}
h.curPos = pos
}
// clearWrap clears the state where the cursor is in the margin
// waiting for the next character before wrapping the line. This must
// be done before most operations that act on the cursor.
func (h *windowsAnsiEventHandler) clearWrap() {
h.wrapNext = false
h.drewMarginByte = false
}
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