go-prompt/prompt/prompt.go
2017-07-15 20:22:56 +09:00

135 lines
2.3 KiB
Go

package prompt
import (
"syscall"
"os"
"os/signal"
"time"
)
type Executor func(*Buffer) string
type Completer func(*Buffer) []string
type Prompt struct {
in *VT100Parser
buf *Buffer
renderer *Render
title string
executor Executor
completer Completer
}
func (p *Prompt) Run() {
p.setUp()
defer p.tearDown()
bufCh := make(chan []byte, 128)
go readBuffer(bufCh)
exitCh := make(chan bool, 16)
winSizeCh := make(chan *WinSize, 128)
go handleSignals(p.in, exitCh, winSizeCh)
for {
select {
case b := <- bufCh:
p.renderer.Erase(p.buf)
ac := p.in.GetASCIICode(b)
if ac == nil {
p.buf.InsertText(string(b), false, true)
} else if ac.Key == ControlJ || ac.Key == Enter {
res := p.executor(p.buf)
p.renderer.BreakLine(p.buf, res)
p.buf = NewBuffer()
} else if ac.Key == ControlC {
return
} else {
InputHandler(ac, p.buf)
}
completions := p.completer(p.buf)
p.renderer.Render(p.buf, completions)
case w := <- winSizeCh:
p.renderer.UpdateWinSize(w)
case e := <- exitCh:
if e {
return
}
default:
time.Sleep(10 * time.Millisecond)
}
}
}
func (p *Prompt) setUp() {
p.in.Setup()
p.renderer.Setup()
}
func (p *Prompt) tearDown() {
p.in.TearDown()
p.renderer.TearDown()
}
func readBuffer(bufCh chan []byte) {
buf := make([]byte, 1024)
for {
if n, err := syscall.Read(syscall.Stdin, buf); err == nil {
bufCh <- buf[:n]
}
}
}
func handleSignals(in *VT100Parser, exitCh chan bool, winSizeCh chan *WinSize) {
sigCh := make(chan os.Signal, 1)
signal.Notify(
sigCh,
syscall.SIGHUP,
syscall.SIGINT,
syscall.SIGTERM,
syscall.SIGQUIT,
syscall.SIGWINCH,
)
for {
s := <-sigCh
switch s {
// kill -SIGHUP XXXX
case syscall.SIGHUP:
exitCh <- true
// kill -SIGINT XXXX or Ctrl+c
case syscall.SIGINT:
exitCh <- true
// kill -SIGTERM XXXX
case syscall.SIGTERM:
exitCh <- true
// kill -SIGQUIT XXXX
case syscall.SIGQUIT:
exitCh <- true
case syscall.SIGWINCH:
winSizeCh <- in.GetWinSize()
default:
}
}
}
func NewPrompt(executor Executor, completer Completer) *Prompt {
return &Prompt{
in: NewVT100Parser(),
renderer: &Render{
Prefix: ">>> ",
out: NewVT100Writer(),
},
title: "Hello! this is prompt toolkit",
buf: NewBuffer(),
executor: executor,
completer: completer,
}
}