readline/readline.go

334 lines
7.0 KiB
Go

// Readline is a pure go implementation for GNU-Readline kind library.
//
// example:
// rl, err := readline.New(readline.StaticPrompt("> "))
// if err != nil {
// panic(err)
// }
// defer rl.Close()
//
// for {
// line, err := rl.Readline()
// if err != nil { // io.EOF
// break
// }
// println(line)
// }
//
package readline
import (
"fmt"
"io"
)
type Instance struct {
Config *Config
Terminal *Terminal
Operation *Operation
}
type Config struct {
// prompt supports ANSI escape sequence, so we can color some characters even in windows
Prompt fmt.Stringer
// readline will persist historys to file where HistoryFile specified
HistoryFile string
// specify the max length of historys, it's 500 by default, set it to -1 to disable history
HistoryLimit int
DisableAutoSaveHistory bool
// enable case-insensitive history searching
HistorySearchFold bool
// AutoCompleter will called once user press TAB
AutoComplete AutoCompleter
// Any key press will pass to Listener
// NOTE: Listener will be triggered by (nil, 0, 0) immediately
Listener Listener
Painter Painter
// If VimMode is true, readline will in vim.insert mode by default
VimMode bool
InterruptPrompt string
EOFPrompt string
FuncGetWidth func() int
Stdin io.ReadCloser
StdinWriter io.Writer
Stdout io.Writer
Stderr io.Writer
EnableMask bool
MaskRune rune
// erase the editing line after user submited it
// it use in IM usually.
UniqueEditLine bool
// filter input runes (may be used to disable CtrlZ or for translating some keys to different actions)
// -> output = new (translated) rune and true/false if continue with processing this one
FuncFilterInputRune func(rune) (rune, bool)
// force use interactive even stdout is not a tty
FuncIsTerminal func() bool
FuncMakeRaw func() error
FuncExitRaw func() error
FuncOnWidthChanged func(func())
ForceUseInteractive bool
// private fields
inited bool
opHistory *opHistory
opSearch *opSearch
}
func (c *Config) useInteractive() bool {
if c.ForceUseInteractive {
return true
}
return c.FuncIsTerminal()
}
func (c *Config) Init() error {
if c.inited {
return nil
}
c.inited = true
if c.Stdin == nil {
c.Stdin = NewCancelableStdin(Stdin)
}
c.Stdin, c.StdinWriter = NewFillableStdin(c.Stdin)
if c.Stdout == nil {
c.Stdout = Stdout
}
if c.Stderr == nil {
c.Stderr = Stderr
}
if c.HistoryLimit == 0 {
c.HistoryLimit = 500
}
if c.InterruptPrompt == "" {
c.InterruptPrompt = "^C"
} else if c.InterruptPrompt == "\n" {
c.InterruptPrompt = ""
}
if c.EOFPrompt == "" {
c.EOFPrompt = "^D"
} else if c.EOFPrompt == "\n" {
c.EOFPrompt = ""
}
if c.AutoComplete == nil {
c.AutoComplete = &TabCompleter{}
}
if c.FuncGetWidth == nil {
c.FuncGetWidth = GetScreenWidth
}
if c.FuncIsTerminal == nil {
c.FuncIsTerminal = DefaultIsTerminal
}
rm := new(RawMode)
if c.FuncMakeRaw == nil {
c.FuncMakeRaw = rm.Enter
}
if c.FuncExitRaw == nil {
c.FuncExitRaw = rm.Exit
}
if c.FuncOnWidthChanged == nil {
c.FuncOnWidthChanged = DefaultOnWidthChanged
}
return nil
}
func (c Config) Clone() *Config {
c.opHistory = nil
c.opSearch = nil
return &c
}
func (c *Config) SetListener(f func(line []rune, pos int, key rune) (newLine []rune, newPos int, ok bool)) {
c.Listener = FuncListener(f)
}
func (c *Config) SetPainter(p Painter) {
c.Painter = p
}
func NewEx(cfg *Config) (*Instance, error) {
t, err := NewTerminal(cfg)
if err != nil {
return nil, err
}
rl := t.Readline()
if cfg.Painter == nil {
cfg.Painter = &defaultPainter{}
}
return &Instance{
Config: cfg,
Terminal: t,
Operation: rl,
}, nil
}
type Prompter interface {
String() string
}
func New(prompt fmt.Stringer) (*Instance, error) {
return NewEx(&Config{Prompt: prompt})
}
func (i *Instance) ResetHistory() {
i.Operation.ResetHistory()
}
func (i *Instance) SetPrompt(s fmt.Stringer) {
i.Operation.SetPrompt(s)
}
func (i *Instance) SetMaskRune(r rune) {
i.Operation.SetMaskRune(r)
}
// change history persistence in runtime
func (i *Instance) SetHistoryPath(p string) {
i.Operation.SetHistoryPath(p)
}
// readline will refresh automatic when write through Stdout()
func (i *Instance) Stdout() io.Writer {
return i.Operation.Stdout()
}
// readline will refresh automatic when write through Stdout()
func (i *Instance) Stderr() io.Writer {
return i.Operation.Stderr()
}
// switch VimMode in runtime
func (i *Instance) SetVimMode(on bool) {
i.Operation.SetVimMode(on)
}
func (i *Instance) IsVimMode() bool {
return i.Operation.IsEnableVimMode()
}
func (i *Instance) GenPasswordConfig() *Config {
return i.Operation.GenPasswordConfig()
}
// we can generate a config by `i.GenPasswordConfig()`
func (i *Instance) ReadPasswordWithConfig(cfg *Config) ([]byte, error) {
return i.Operation.PasswordWithConfig(cfg)
}
func (i *Instance) ReadPasswordEx(prompt fmt.Stringer, l Listener) ([]byte, error) {
return i.Operation.PasswordEx(prompt, l)
}
func (i *Instance) ReadPassword(prompt fmt.Stringer) ([]byte, error) {
return i.Operation.Password(prompt)
}
type Result struct {
Line string
Error error
}
func (l *Result) CanContinue() bool {
return len(l.Line) != 0 && l.Error == ErrInterrupt
}
func (l *Result) CanBreak() bool {
return !l.CanContinue() && l.Error != nil
}
func (i *Instance) Line() *Result {
ret, err := i.Readline()
return &Result{ret, err}
}
// err is one of (nil, io.EOF, readline.ErrInterrupt)
func (i *Instance) Readline() (string, error) {
return i.Operation.String()
}
func (i *Instance) ReadlineWithDefault(what string) (string, error) {
i.Operation.SetBuffer(what)
return i.Operation.String()
}
func (i *Instance) SaveHistory(content string) error {
return i.Operation.SaveHistory(content)
}
// same as readline
func (i *Instance) ReadSlice() ([]byte, error) {
return i.Operation.Slice()
}
// we must make sure that call Close() before process exit.
func (i *Instance) Close() error {
if err := i.Terminal.Close(); err != nil {
return err
}
i.Config.Stdin.Close()
i.Operation.Close()
return nil
}
func (i *Instance) Clean() {
i.Operation.Clean()
}
func (i *Instance) Write(b []byte) (int, error) {
return i.Stdout().Write(b)
}
// WriteStdin prefill the next Stdin fetch
// Next time you call ReadLine() this value will be writen before the user input
// ie :
// i := readline.New()
// i.WriteStdin([]byte("test"))
// _, _= i.Readline()
//
// gives
//
// > test[cursor]
func (i *Instance) WriteStdin(val []byte) (int, error) {
return i.Terminal.WriteStdin(val)
}
func (i *Instance) SetConfig(cfg *Config) *Config {
if i.Config == cfg {
return cfg
}
old := i.Config
i.Config = cfg
i.Operation.SetConfig(cfg)
i.Terminal.SetConfig(cfg)
return old
}
func (i *Instance) Refresh() {
i.Operation.Refresh()
}
// HistoryDisable the save of the commands into the history
func (i *Instance) HistoryDisable() {
i.Operation.history.Disable()
}
// HistoryEnable the save of the commands into the history (default on)
func (i *Instance) HistoryEnable() {
i.Operation.history.Enable()
}