// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: MIT

package nfs4

import (
	"bytes"
	"testing"

	"sourcedock.dev/petrbalvin/nfs/internal/xdr"
)

func TestDirDelegationShapes(t *testing.T) {
	t.Parallel()
	st := Stateid{1, 'D', 'D', 'E'}

	args := AppendGetDirDelegationArgs(nil, true, OfBits(NotifyAddEntry),
		NfsTime{Seconds: 5, Nseconds: 6}, NfsTime{Seconds: 7, Nseconds: 8},
		Bitmap{}, Bitmap{})
	d := xdr.NewDecoder(args[4:])
	if sig, err := d.Bool(); err != nil || !sig {
		t.Fatalf("signal %v: %v", sig, err)
	}
	if _, err := ReadBitmap(d); err != nil {
		t.Fatal(err)
	}
	for _, want := range []NfsTime{{Seconds: 5, Nseconds: 6}, {Seconds: 7, Nseconds: 8}} {
		s, err := d.Int64()
		if err != nil || s != want.Seconds {
			t.Fatalf("delay seconds %d: %v", s, err)
		}
		ns, err := d.Uint32()
		if err != nil || ns != want.Nseconds {
			t.Fatalf("delay nseconds %d: %v", ns, err)
		}
	}
	if _, err := ReadBitmap(d); err != nil {
		t.Fatal(err)
	}
	if _, err := ReadBitmap(d); err != nil {
		t.Fatal(err)
	}
	if d.Remaining() != 0 {
		t.Fatalf("%d bytes left in the dir delegation args", d.Remaining())
	}

	ok := AppendGetDirDelegationResOK(nil, [8]byte{9}, st,
		OfBits(NotifyAddEntry), Bitmap{}, Bitmap{})
	n, err := resBodyLen(OpGetDirDelegation, ErrOK, ok)
	if err != nil || n != len(ok) {
		t.Fatalf("resok measured %d of %d: %v", n, len(ok), err)
	}
	un := AppendGetDirDelegationResUnavail(nil, true)
	if n, err := resBodyLen(OpGetDirDelegation, ErrOK, un); err != nil || n != len(un) {
		t.Fatalf("unavail measured %d of %d: %v", n, len(un), err)
	}
	d = xdr.NewDecoder(un)
	if s, err := d.Uint32(); err != nil || s != GddUnavail {
		t.Fatalf("unavail status %d: %v", s, err)
	}
}

func TestNotifyShapes(t *testing.T) {
	t.Parallel()
	add := AppendNotifyAdd(nil, "entry", 0, true)
	d := xdr.NewDecoder(add)
	if n, err := d.Uint32(); err != nil || n != 0 {
		t.Fatalf("old entries %d: %v", n, err)
	}
	if name, err := d.String(); err != nil || name != "entry" {
		t.Fatalf("name %q: %v", name, err)
	}
	if _, err := ReadBitmap(d); err != nil { // empty fattr bitmap
		t.Fatal(err)
	}
	if _, err := d.VarOpaque(); err != nil { // empty fattr blob
		t.Fatal(err)
	}
	for range 2 {
		if _, err := d.Uint32(); err != nil {
			t.Fatal(err)
		}
	}
	if last, err := d.Bool(); err != nil || !last {
		t.Fatalf("last %v: %v", last, err)
	}
	if d.Remaining() != 0 {
		t.Fatalf("%d bytes left in the add body", d.Remaining())
	}

	rem := AppendNotifyRemove(nil, "gone", 7)
	d = xdr.NewDecoder(rem)
	if name, err := d.String(); err != nil || name != "gone" {
		t.Fatalf("name %q: %v", name, err)
	}
	if _, err := ReadBitmap(d); err != nil {
		t.Fatal(err)
	}
	if _, err := d.VarOpaque(); err != nil {
		t.Fatal(err)
	}
	if c, err := d.Uint64(); err != nil || c != 7 {
		t.Fatalf("cookie %d: %v", c, err)
	}

	// CB_NOTIFY args round trip through the decoder the client uses.
	st := Stateid{2, 'N'}
	fh := []byte("dir-fh")
	changes := []Notify4{{Mask: OfBits(NotifyAddEntry), Vals: add}}
	cb := AppendCBNotifyArgs(nil, st, fh, changes)
	if n, err := resBodyLenCB(OpCBSequence, ErrOK, make([]byte, 32)); err != nil {
		t.Fatal(err)
	} else if n != 32 {
		t.Fatalf("cb sequence body %d", n)
	}
	got, err := DecodeCBNotifyArgs(xdr.NewDecoder(cb[4:]))
	if err != nil {
		t.Fatal(err)
	}
	if got.Stateid != st || !bytes.Equal(got.FH, fh) || len(got.Changes) != 1 {
		t.Fatalf("decoded %+v", got)
	}
	if !got.Changes[0].Mask.Has(NotifyAddEntry) {
		t.Fatalf("mask %v", got.Changes[0].Mask)
	}

	// CB_NOTIFY_LOCK args round trip.
	nl := AppendCBNotifyLockArgs(nil, fh, 0x77, []byte("owner"))
	lock, err := DecodeCBNotifyLockArgs(xdr.NewDecoder(nl[4:]))
	if err != nil {
		t.Fatal(err)
	}
	if lock.Clientid != 0x77 || string(lock.Owner) != "owner" || !bytes.Equal(lock.FH, fh) {
		t.Fatalf("decoded %+v", lock)
	}
	if n, err := resBodyLenCB(OpCBNotifyLock, ErrOK, nil); err != nil || n != 0 {
		t.Fatalf("notify lock res body %d: %v", n, err)
	}
}