package liquidsoap

import (
	"os"
	"os/exec"
	"syscall"
)

// End describes how liquidsoap ended; successfully? With errors?
type End struct {
	Retval int
	Err    error
}

// Success returns true if the process ended successfully
func (e *End) Success() bool {
	if e.Err == nil && e.Retval == 0 {
		return true
	}
	return false
}

// RunLiquidsoap will launch a new instance of liquidsoap and take control of it. It will also read output
// messages and send them to out chan. No magic will be done to liquidsoap config file, so if you want output
// messages, don't forget to set("log.stderr", true) in your liquidsoap file.
//
// RunLiquidsoap is an async function, which provides channels as feedback and needs a channel to ask for its
// termination
func RunLiquidsoap(configfile string, kill <-chan struct{}) (<-chan Output, <-chan End, error) {
	out := make(chan Output)
	exit := make(chan End, 1)
	cmd := exec.Command("liquidsoap", "--enable-telnet", configfile)
	cmd.Stderr = os.Stderr // connect liquidsoap err to process stderr
	log, err := cmd.StdoutPipe()
	if err != nil {
		return nil, nil, err
	}
	endparse := make(chan interface{})
	go Parse(log, out, endparse)
	err = cmd.Start()
	proc := cmd.Process
	go func() {
		<-kill
		proc.Signal(syscall.SIGINT)
	}()
	go func() {
		<-endparse
		err := cmd.Wait()
		close(out)
		if err != nil {
			exit <- End{Err: err}
		} else {
			exit <- End{}
		}
		close(exit)
	}()
	return out, exit, err
}