package shell

import (
	"io/ioutil"
	"os"
	"os/exec"
	"strings"
	"time"

	"go.wit.com/log"
)

// TODO: look at https://github.com/go-cmd/cmd/issues/20
// use go-cmd instead here?

var callback func(interface{}, int)

var shellStdout *os.File
var shellStderr *os.File

var spewOn bool = false
var quiet bool = false

// var msecDelay   int  = 20	// number of milliseconds to delay between reads with no data

// var bytesBuffer bytes.Buffer
// var bytesSplice []byte

func handleError(c interface{}, ret int) {
	log.Log(INFO, "shell.Run() Returned", ret)
	if callback != nil {
		callback(c, ret)
	}
}

func init() {
	callback = nil
}

func InitCallback(f func(interface{}, int)) {
	callback = f
}

// this means it won't copy all the output to STDOUT
func Quiet(q bool) {
	quiet = q
}

func Script(cmds string) int {
	// split on new lines (while we are at it, handle stupid windows text files
	lines := strings.Split(strings.Replace(cmds, "\r\n", "\n", -1), "\n")

	for _, line := range lines {
		line = Chomp(line) // this is like 'chomp' in perl
		log.Log(INFO, "LINE:", line)
		time.Sleep(1)
		RunString(line)
	}
	return 0
}

func SpewOn() {
	spewOn = true
}

func SetDelayInMsec(msecs int) {
	msecDelay = msecs
}

func SetStdout(newout *os.File) {
	shellStdout = newout
}

func SetStderr(newerr *os.File) {
	shellStderr = newerr
}

func Unlink(filename string) bool {
	if err := os.Remove(filename); err != nil {
		return Exists(filename)
	} else {
		return Exists(filename)
	}
}

func RM(filename string) {
	os.Remove(Path(filename))
}

func Daemon(cmdline string, timeout time.Duration) int {
	for {
		RunString(cmdline)
		time.Sleep(timeout)
	}
}

// run something and never return from it
// TODO: pass STDOUT, STDERR, STDIN correctly
// TODO: figure out how to nohup the process and exit
func Exec(cmdline string) {
	log.Log(INFO, "shell.Run() START "+cmdline)

	cmd := Chomp(cmdline) // this is like 'chomp' in perl
	cmdArgs := strings.Fields(cmd)

	process := exec.Command(cmdArgs[0], cmdArgs[1:len(cmdArgs)]...)
	process.Stderr = os.Stderr
	process.Stdin = os.Stdin
	process.Stdout = os.Stdout
	process.Start()
	err := process.Wait()
	log.Log(INFO, "shell.Exec() err =", err)
	os.Exit(0)
}

// run interactively. output from the cmd is in real time
func NewRun(workingpath string, cmd []string) error {
	log.Log(INFO, "NewRun() ", cmd)

	process := exec.Command(cmd[0], cmd[1:len(cmd)]...)
	// Set the working directory
	process.Dir = workingpath
	process.Stderr = os.Stderr
	process.Stdin = os.Stdin
	process.Stdout = os.Stdout
	process.Start()
	err := process.Wait()
	log.Log(INFO, "shell.Exec() err =", err)
	return err
}

// return true if the filename exists (cross-platform)
func Exists(filename string) bool {
	_, err := os.Stat(Path(filename))
	if os.IsNotExist(err) {
		return false
	}
	return true
}

// makes the directory
func Mkdir(dir string) bool {
	if Dir(dir) {
		// already a dir
		return true
	}
	if Exists(dir) {
		// something else is there
		return false
	}
	Run([]string{"mkdir", "-p", dir})
	return true
}

func IsDir(dirname string) bool {
	return Dir(dirname)
}

// return true if the filename exists (cross-platform)
func Dir(dirname string) bool {
	info, err := os.Stat(Path(dirname))
	if os.IsNotExist(err) {
		return false
	}
	return info.IsDir()
}

// Cat a file into a string
func Cat(filename string) string {
	buffer, err := ioutil.ReadFile(Path(filename))
	// log.Log(INFO, "buffer =", string(buffer))
	if err != nil {
		return ""
	}
	return Chomp(buffer)
}