package subprocess

import (
	"errors"
	"os/exec"
	"time"
)

const (
	gracefulTerminationWait = 2 * time.Second
	forcefulTerminationWait = 2 * time.Second
)

// ownedProcessTree owns every process started by a command invocation.
// Implementations must tolerate a leader that has already exited.
type ownedProcessTree interface {
	Start(*exec.Cmd) error
	TerminateGracefully() error
	TerminateForcefully() error
	Dispose() error
}

func joinErrors(errs ...error) error {
	filtered := make([]error, 0, len(errs))
	for _, err := range errs {
		if err != nil {
			filtered = append(filtered, err)
		}
	}
	return errors.Join(filtered...)
}