feat: add ssh server

backend/pkg/proto/ssh/client/parse.go

@@ -0,0 +1,67 @@
+package client
+
+import (
+	"bytes"
+	"sync"
+)
+
+type Parser struct {
+	lock         sync.Mutex
+	vimState     bool
+	commandState bool
+}
+
+var (
+	enterMarks = [][]byte{
+		[]byte("\x1b[?1049h"),
+		[]byte("\x1b[?1048h"),
+		[]byte("\x1b[?1047h"),
+		[]byte("\x1b[?47h"),
+	}
+
+	exitMarks = [][]byte{
+		[]byte("\x1b[?1049l"),
+		[]byte("\x1b[?1048l"),
+		[]byte("\x1b[?1047l"),
+		[]byte("\x1b[?47l"),
+	}
+	screenMarks = [][]byte{
+		{0x1b, 0x5b, 0x4b, 0x0d, 0x0a},
+		{0x1b, 0x5b, 0x34, 0x6c},
+	}
+)
+
+func (p *Parser) State(b []byte) bool {
+	if !p.vimState && IsEditEnterMode(b) {
+		if !isNewScreen(b) {
+			p.vimState = true
+			p.commandState = false
+		}
+	}
+	if p.vimState && IsEditExitMode(b) {
+		p.vimState = false
+		p.commandState = true
+	}
+	return p.vimState
+}
+
+func isNewScreen(p []byte) bool {
+	return matchMark(p, screenMarks)
+}
+
+func IsEditEnterMode(p []byte) bool {
+	return matchMark(p, enterMarks)
+}
+
+func IsEditExitMode(p []byte) bool {
+	return matchMark(p, exitMarks)
+}
+
+func matchMark(p []byte, marks [][]byte) bool {
+	for _, item := range marks {
+		if bytes.Contains(p, item) {
+			return true
+		}
+	}
+	return false
+}