package hostbox

import (
	"context"
	"path"
	"strings"
)

// IntendRole commits the empty child's exact parent and reserved name before
// mkdir. Only Reserve can turn it into execution authority.
func (j *LaunchJournal) IntendRole(ctx context.Context, r LaunchReservation) error {
	if j == nil {
		return ErrUnsupported
	}
	if j.remote != nil {
		out, err := journalCall(ctx, j.remote, JournalRequest{Op: "intend", Reservation: r})
		_ = out
		return err
	}

	if r.NeverIntended || r.ID == "" || r.Role == "" || r.InvocationID == "" || r.Inputs == "" || r.State != "" || r.PID != 0 || r.ProcessStart != "" || r.Group.Device != 0 || r.Group.Inode != 0 || r.Group.InvocationID != r.InvocationID || r.Executable.Device == 0 || r.Executable.Inode == 0 || r.Parent.Device == 0 || r.Parent.Inode == 0 || !managedName(r.Parent.RelativePath) || path.Dir(r.Group.RelativePath) != r.Parent.RelativePath || !strings.HasPrefix(path.Base(r.Group.RelativePath), "role-") || !managedName(r.Group.RelativePath) {
		return ErrUnsupported
	}
	return j.mutate(ctx, r.Target, func(in *LaunchInventory) error {
		parent := false
		for _, g := range in.Groups {
			if g == r.Parent {
				parent = true
			}
		}
		if !parent {
			return ErrChanged
		}
		for _, old := range in.Reservations {
			if old.ID == r.ID || old.Group.RelativePath == r.Group.RelativePath {
				return ErrChanged
			}
		}
		for _, g := range in.Groups {
			if g.RelativePath == r.Group.RelativePath {
				return ErrChanged
			}
		}
		r.State = "intended"
		in.Reservations = append(in.Reservations, r)
		return nil
	})
}