Use Survey For Interactions With User (#186)

fixes

Use Survey For Interactions With User

Add Vendor "github.com/AlecAivazis/survey/v2"

Co-authored-by: Norwin Roosen <git@nroo.de>
Co-authored-by: 6543 <6543@obermui.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/186
Reviewed-by: techknowlogick <techknowlogick@gitea.io>
Reviewed-by: Norwin <noerw@noreply.gitea.io>

vendor/github.com/AlecAivazis/survey/v2/terminal/runereader_posix.go

@@ -0,0 +1,111 @@
+// +build !windows
+
+// The terminal mode manipulation code is derived heavily from:
+// https://github.com/golang/crypto/blob/master/ssh/terminal/util.go:
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package terminal
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"syscall"
+	"unsafe"
+)
+
+type runeReaderState struct {
+	term   syscall.Termios
+	reader *bufio.Reader
+	buf    *bytes.Buffer
+}
+
+func newRuneReaderState(input FileReader) runeReaderState {
+	buf := new(bytes.Buffer)
+	return runeReaderState{
+		reader: bufio.NewReader(&BufferedReader{
+			In:     input,
+			Buffer: buf,
+		}),
+		buf: buf,
+	}
+}
+
+func (rr *RuneReader) Buffer() *bytes.Buffer {
+	return rr.state.buf
+}
+
+// For reading runes we just want to disable echo.
+func (rr *RuneReader) SetTermMode() error {
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(rr.stdio.In.Fd()), ioctlReadTermios, uintptr(unsafe.Pointer(&rr.state.term)), 0, 0, 0); err != 0 {
+		return err
+	}
+
+	newState := rr.state.term
+	newState.Lflag &^= syscall.ECHO | syscall.ECHONL | syscall.ICANON | syscall.ISIG
+
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(rr.stdio.In.Fd()), ioctlWriteTermios, uintptr(unsafe.Pointer(&newState)), 0, 0, 0); err != 0 {
+		return err
+	}
+
+	return nil
+}
+
+func (rr *RuneReader) RestoreTermMode() error {
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(rr.stdio.In.Fd()), ioctlWriteTermios, uintptr(unsafe.Pointer(&rr.state.term)), 0, 0, 0); err != 0 {
+		return err
+	}
+	return nil
+}
+
+func (rr *RuneReader) ReadRune() (rune, int, error) {
+	r, size, err := rr.state.reader.ReadRune()
+	if err != nil {
+		return r, size, err
+	}
+
+	// parse ^[ sequences to look for arrow keys
+	if r == '\033' {
+		if rr.state.reader.Buffered() == 0 {
+			// no more characters so must be `Esc` key
+			return KeyEscape, 1, nil
+		}
+		r, size, err = rr.state.reader.ReadRune()
+		if err != nil {
+			return r, size, err
+		}
+		if r != '[' {
+			return r, size, fmt.Errorf("Unexpected Escape Sequence: %q", []rune{'\033', r})
+		}
+		r, size, err = rr.state.reader.ReadRune()
+		if err != nil {
+			return r, size, err
+		}
+		switch r {
+		case 'D':
+			return KeyArrowLeft, 1, nil
+		case 'C':
+			return KeyArrowRight, 1, nil
+		case 'A':
+			return KeyArrowUp, 1, nil
+		case 'B':
+			return KeyArrowDown, 1, nil
+		case 'H': // Home button
+			return SpecialKeyHome, 1, nil
+		case 'F': // End button
+			return SpecialKeyEnd, 1, nil
+		case '3': // Delete Button
+			// discard the following '~' key from buffer
+			rr.state.reader.Discard(1)
+			return SpecialKeyDelete, 1, nil
+		default:
+			// discard the following '~' key from buffer
+			rr.state.reader.Discard(1)
+			return IgnoreKey, 1, nil
+		}
+		return r, size, fmt.Errorf("Unknown Escape Sequence: %q", []rune{'\033', '[', r})
+	}
+	return r, size, err
+}