package container

import (
	"encoding/gob"
	"fmt"
)

func init() { gob.Register(new(RemountOp)) }

// Remount appends an [Op] that applies [RemountOp.Flags] on container path [RemountOp.Target].
func (f *Ops) Remount(target *Absolute, flags uintptr) *Ops {
	*f = append(*f, &RemountOp{target, flags})
	return f
}

// RemountOp remounts Target with Flags.
type RemountOp struct {
	Target *Absolute
	Flags  uintptr
}

func (r *RemountOp) Valid() bool           { return r != nil && r.Target != nil }
func (*RemountOp) early(*setupState) error { return nil }
func (r *RemountOp) apply(*setupState) error {
	return wrapErrSuffix(hostProc.remount(toSysroot(r.Target.String()), r.Flags),
		fmt.Sprintf("cannot remount %q:", r.Target))
}

func (r *RemountOp) Is(op Op) bool {
	vr, ok := op.(*RemountOp)
	return ok && r.Valid() && vr.Valid() &&
		r.Target.Is(vr.Target) &&
		r.Flags == vr.Flags
}
func (*RemountOp) prefix() string   { return "remounting" }
func (r *RemountOp) String() string { return fmt.Sprintf("%q flags %#x", r.Target, r.Flags) }