package camfish

import "fmt"
import "log"
import "time"
import "iter"
import "errors"
import "strconv"
import "syscall"
import "os/user"
import "strings"
import "context"
import "sync/atomic"
import "unicode/utf8"

func defaul[T comparable](value, def T) T {
	var zero T
	if value == zero { return def }
	return value
}

func panicWrap(f func() error) (err error) {
	defer func () {
		if pan := recover(); pan != nil {
			if panErr, ok := pan.(error); ok {
				err = panErr
			} else {
				err = errors.New(fmt.Sprint(pan))
			}
		}
	} ()
	
	err = f()
	return
}

func panicWrapCtx(ctx context.Context, f func(context.Context) error) (err error) {
	defer func () {
		if pan := recover(); pan != nil {
			if panErr, ok := pan.(error); ok {
				err = panErr
			} else {
				err = errors.New(fmt.Sprint(pan))
			}
		}
	} ()
	
	err = f(ctx)
	return
}

type atomicDuration atomic.Int64
type atomicInt64Ptr = *atomic.Int64

func (duration* atomicDuration) Load() time.Duration {
	return time.Duration((*atomic.Int64)(duration).Load())
}

func (duration *atomicDuration) Store(newDuration time.Duration) {
	(*atomic.Int64)(duration).Store(int64(newDuration))
}

func logActors (actors iter.Seq[Actor]) {
	output := "actors: "
	x := utf8.RuneCountInString(output)
	first := true
	line := func () {		
		if output == "" { return }
		if first {
			first = false
			log.Println("(i)", output)
		} else {
			log.Println("   ", output)
		}
		output = ""
		x = 0
	}
	types := make(map[string] int)
	for actor := range actors {
		types[actor.Type()] += 1
	}
	for typ, count := range types {
		if count > 1 {
			typ += fmt.Sprintf("(%d)", count)
		}
		typ += ", "
		x += 2
		typeLen := utf8.RuneCountInString(typ)
		if x + typeLen >= 60 {
			line()
		}
		output += typ
		x += typeLen
	}
	if output != "" {
		output = strings.TrimSuffix(output, ", ")
	}
	line()
}

func dropPrivelege (usr, group string) error {
	if group != "" {
		groupInfo, err := user.LookupGroup(group)
		if err != nil { return err }
		gid, err := strconv.Atoi(groupInfo.Gid)
		if err != nil { return err }
		err = syscall.Setgid(gid)
		if err != nil { return err }
	}
	if usr != "" {
		usrInfo, err := user.Lookup(usr)
		if err != nil { return err }
		uid, err := strconv.Atoi(usrInfo.Uid)
		if err != nil { return err }
		err = syscall.Setuid(uid)
		if err != nil { return err }
	}
	return nil
}