package liquidsoap

import (
	"os/exec"
	"syscall"

	"github.com/pkg/errors"
)

var ErrNotRunning = errors.New("liquidsoap is not running")

type Liquidsoap struct {
	command *exec.Cmd
}

func NewLiquidsoap(liquidsoapPath, scriptPath string) (*Liquidsoap, error) {
	if _, err := exec.LookPath(liquidsoapPath); err != nil {
		return nil, err
	}

	out, err := exec.Command(liquidsoapPath, "--verbose", "-c", scriptPath).CombinedOutput()
	if err != nil {
		return nil, errors.Wrap(err, "cannot check script")
	}

	if len(out) > 0 {
		return nil, errors.Errorf("script validation failed: %s", string(out))
	}

	cmd := exec.Command(liquidsoapPath, scriptPath)

	if err := cmd.Start(); err != nil {
		return nil, err
	}

	return &Liquidsoap{
		command: cmd}, nil
}

func (l *Liquidsoap) Stop() error {
	if l.command.Process == nil && l.command.ProcessState != nil {
		return ErrNotRunning
	}

	if err := l.command.Process.Signal(syscall.SIGINT); err != nil {
		return err
	}

	if err := l.command.Wait(); err != nil {
		return err
	}

	return nil
}