package process

import (
	"errors"
	"fmt"
)

type RegisterNewProc[T Proc] func() (T, error)

var (
	ErrNoProcFound   = errors.New("cannot locate procType")
	ErrNoProcess     = errors.New("process not running")
	ErrNoCallStart   = errors.New("process ared runnning, dont call Start")
	ErrAppendProcess = errors.New("cannot append to makeProcs register")

	makeProcs = make(map[string]RegisterNewProc[Proc])
)

// RegisterProcess new proc
func RegisterProcess[T Proc](makeProc RegisterNewProc[T], names ...string) error {
	if makeProcs == nil {
		return ErrAppendProcess
	}

	for _, name := range names {
		makeProcs[name] = func() (proc Proc, err error) {
			defer func() {
				if err2, ok := recover().(error); ok && err != nil {
					err = fmt.Errorf("return new process: %w", err2)
				}
			}()
			return makeProc()
		}
	}
	return nil
}

// Return new process struct
func GetNewProc(typeName string) (Proc, error) {
	if newProc, ok := makeProcs[typeName]; ok {
		return newProc()
	}
	return nil, ErrNoProcFound
}

// Make new process and start command
func ReturnNewProcess(typeName string, options *Exec) (Proc, error) {
	if newProc, ok := makeProcs[typeName]; ok {
		proc, err := newProc()
		if err != nil {
			return nil, err
		}
		err = proc.Start(options)
		return proc, err
	}
	return nil, ErrNoProcFound
}