package readline import ( "bytes" "io" "strings" "github.com/chzyer/readline/runes" ) type runeBufferBck struct { buf []rune idx int } type RuneBuffer struct { buf []rune idx int prompt []rune w io.Writer mask rune cleanInScreen bool bck *runeBufferBck } func (r *RuneBuffer) Backup() { r.bck = &runeBufferBck{r.buf, r.idx} } func (r *RuneBuffer) Restore() { r.Refresh(func() { if r.bck == nil { return } r.buf = r.bck.buf r.idx = r.bck.idx }) } func NewRuneBuffer(w io.Writer, prompt string, mask rune) *RuneBuffer { rb := &RuneBuffer{ w: w, mask: mask, } rb.SetPrompt(prompt) return rb } func (r *RuneBuffer) SetMask(m rune) { r.mask = m } func (r *RuneBuffer) CurrentWidth(x int) int { return runes.WidthAll(r.buf[:x]) } func (r *RuneBuffer) PromptLen() int { return runes.WidthAll(runes.ColorFilter(r.prompt)) } func (r *RuneBuffer) RuneSlice(i int) []rune { if i > 0 { rs := make([]rune, i) copy(rs, r.buf[r.idx:r.idx+i]) return rs } rs := make([]rune, -i) copy(rs, r.buf[r.idx+i:r.idx]) return rs } func (r *RuneBuffer) Runes() []rune { newr := make([]rune, len(r.buf)) copy(newr, r.buf) return newr } func (r *RuneBuffer) Pos() int { return r.idx } func (r *RuneBuffer) Len() int { return len(r.buf) } func (r *RuneBuffer) MoveToLineStart() { r.Refresh(func() { if r.idx == 0 { return } r.idx = 0 }) } func (r *RuneBuffer) MoveBackward() { r.Refresh(func() { if r.idx == 0 { return } r.idx-- }) } func (r *RuneBuffer) WriteString(s string) { r.WriteRunes([]rune(s)) } func (r *RuneBuffer) WriteRune(s rune) { r.WriteRunes([]rune{s}) } func (r *RuneBuffer) WriteRunes(s []rune) { r.Refresh(func() { tail := append(s, r.buf[r.idx:]...) r.buf = append(r.buf[:r.idx], tail...) r.idx += len(s) }) } func (r *RuneBuffer) MoveForward() { r.Refresh(func() { if r.idx == len(r.buf) { return } r.idx++ }) } func (r *RuneBuffer) Erase() { r.Refresh(func() { r.idx = 0 r.buf = r.buf[:0] }) } func (r *RuneBuffer) Delete() (success bool) { r.Refresh(func() { if r.idx == len(r.buf) { return } r.buf = append(r.buf[:r.idx], r.buf[r.idx+1:]...) success = true }) return } func (r *RuneBuffer) DeleteWord() { if r.idx == len(r.buf) { return } init := r.idx for init < len(r.buf) && IsWordBreak(r.buf[init]) { init++ } for i := init + 1; i < len(r.buf); i++ { if !IsWordBreak(r.buf[i]) && IsWordBreak(r.buf[i-1]) { r.Refresh(func() { r.buf = append(r.buf[:r.idx], r.buf[i-1:]...) }) return } } r.Kill() } func (r *RuneBuffer) MoveToPrevWord() (success bool) { r.Refresh(func() { if r.idx == 0 { return } for i := r.idx - 1; i > 0; i-- { if !IsWordBreak(r.buf[i]) && IsWordBreak(r.buf[i-1]) { r.idx = i success = true return } } r.idx = 0 success = true }) return } func (r *RuneBuffer) KillFront() { r.Refresh(func() { if r.idx == 0 { return } length := len(r.buf) - r.idx copy(r.buf[:length], r.buf[r.idx:]) r.idx = 0 r.buf = r.buf[:length] }) } func (r *RuneBuffer) Kill() { r.Refresh(func() { r.buf = r.buf[:r.idx] }) } func (r *RuneBuffer) Transpose() { r.Refresh(func() { if len(r.buf) == 1 { r.idx++ } if len(r.buf) < 2 { return } if r.idx == 0 { r.idx = 1 } else if r.idx >= len(r.buf) { r.idx = len(r.buf) - 1 } r.buf[r.idx], r.buf[r.idx-1] = r.buf[r.idx-1], r.buf[r.idx] r.idx++ }) } func (r *RuneBuffer) MoveToNextWord() { r.Refresh(func() { for i := r.idx + 1; i < len(r.buf); i++ { if !IsWordBreak(r.buf[i]) && IsWordBreak(r.buf[i-1]) { r.idx = i return } } r.idx = len(r.buf) }) } func (r *RuneBuffer) BackEscapeWord() { r.Refresh(func() { if r.idx == 0 { return } for i := r.idx - 1; i > 0; i-- { if !IsWordBreak(r.buf[i]) && IsWordBreak(r.buf[i-1]) { r.buf = append(r.buf[:i], r.buf[r.idx:]...) r.idx = i return } } r.buf = r.buf[:0] r.idx = 0 }) } func (r *RuneBuffer) Backspace() { r.Refresh(func() { if r.idx == 0 { return } r.idx-- r.buf = append(r.buf[:r.idx], r.buf[r.idx+1:]...) }) } func (r *RuneBuffer) MoveToLineEnd() { r.Refresh(func() { if r.idx == len(r.buf) { return } r.idx = len(r.buf) }) } func (r *RuneBuffer) LineCount() int { return LineCount(runes.WidthAll(r.buf) + r.PromptLen()) } func (r *RuneBuffer) MoveTo(ch rune, prevChar, reverse bool) (success bool) { r.Refresh(func() { if reverse { for i := r.idx - 1; i >= 0; i-- { if r.buf[i] == ch { r.idx = i if prevChar { r.idx++ } success = true return } } return } for i := r.idx + 1; i < len(r.buf); i++ { if r.buf[i] == ch { r.idx = i if prevChar { r.idx-- } success = true return } } }) return } func (r *RuneBuffer) IdxLine() int { totalWidth := runes.WidthAll(r.buf[:r.idx]) + r.PromptLen() w := getWidth() if w == 0 { return 0 } line := totalWidth / w // if cursor is in last colmun and not any character behind it // the cursor will in the first line, otherwise will in the second line // this situation only occurs in golang's Stdout // TODO: figure out why if totalWidth%w == 0 && len(r.buf) == r.idx && !isWindows { line-- } return line } func (r *RuneBuffer) CursorLineCount() int { return r.LineCount() - r.IdxLine() } func (r *RuneBuffer) Refresh(f func()) { r.Clean() if f != nil { f() } r.w.Write(r.output()) r.cleanInScreen = false } func (r *RuneBuffer) output() []byte { buf := bytes.NewBuffer(nil) buf.WriteString(string(r.prompt)) if r.mask != 0 && len(r.buf) > 0 { buf.Write([]byte(strings.Repeat(string(r.mask), len(r.buf)-1))) if r.buf[len(r.buf)-1] == '\n' { buf.Write([]byte{'\n'}) } else { buf.Write([]byte(string(r.mask))) } } else { buf.Write([]byte(string(r.buf))) } if len(r.buf) > r.idx { buf.Write(runes.Backspace(r.buf[r.idx:])) } return buf.Bytes() } func (r *RuneBuffer) Reset() []rune { ret := runes.Copy(r.buf) r.buf = r.buf[:0] r.idx = 0 return ret } func (r *RuneBuffer) calWidth(m int) int { if m > 0 { return runes.WidthAll(r.buf[r.idx : r.idx+m]) } return runes.WidthAll(r.buf[r.idx+m : r.idx]) } func (r *RuneBuffer) SetStyle(start, end int, style string) { if end < start { panic("end < start") } // goto start move := start - r.idx if move > 0 { r.w.Write([]byte(string(r.buf[r.idx : r.idx+move]))) } else { r.w.Write(bytes.Repeat([]byte("\b"), r.calWidth(move))) } r.w.Write([]byte("\033[" + style + "m")) r.w.Write([]byte(string(r.buf[start:end]))) r.w.Write([]byte("\033[0m")) // TODO: move back } func (r *RuneBuffer) SetWithIdx(idx int, buf []rune) { r.Refresh(func() { r.buf = buf r.idx = idx }) } func (r *RuneBuffer) Set(buf []rune) { r.SetWithIdx(len(buf), buf) } func (r *RuneBuffer) SetPrompt(prompt string) { r.prompt = []rune(prompt) } func (r *RuneBuffer) cleanOutput() []byte { buf := bytes.NewBuffer(nil) buf.Write([]byte("\033[J")) // just like ^k :) idxLine := r.IdxLine() if idxLine == 0 { buf.WriteString("\033[2K\r") return buf.Bytes() } for i := 0; i < idxLine; i++ { buf.WriteString("\033[2K\r\033[A") } buf.WriteString("\033[2K\r") return buf.Bytes() } func (r *RuneBuffer) Clean() { if r.cleanInScreen { return } r.cleanInScreen = true r.w.Write(r.cleanOutput()) }