package family

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"golang.org/x/crypto/bcrypt"
)

func testStore(t *testing.T) (*Store, string) {
	t.Helper()
	dir := t.TempDir()
	s, err := Open(dir)
	if err != nil {
		t.Fatal(err)
	}
	s.SetCost(bcrypt.MinCost)
	return s, dir
}

// A member signs in with their own password; the password is never stored; the list survives a reopen.
func TestFamily_AddVerifyPersist(t *testing.T) {
	s, dir := testStore(t)
	pw, err := s.Add("anna")
	if err != nil || len(pw) != 19 {
		t.Fatalf("add: %v %q", err, pw)
	}
	if !s.Verify("anna", pw) || s.Verify("anna", pw+"x") || s.Verify("bela", pw) {
		t.Fatal("verify wrong")
	}
	b, _ := os.ReadFile(filepath.Join(dir, "family.json"))
	if strings.Contains(string(b), pw) {
		t.Fatal("the plain password reached family.json")
	}
	if st, _ := os.Stat(filepath.Join(dir, "family.json")); st.Mode().Perm() != 0o600 {
		t.Fatalf("family.json mode %v", st.Mode().Perm())
	}
	s2, err := Open(dir)
	if err != nil || !s2.Verify("anna", pw) {
		t.Fatalf("the list did not survive a reopen: %v", err)
	}
	if _, err := s.Add("anna"); err != ErrExists {
		t.Fatalf("duplicate: %v", err)
	}
	for _, bad := range []string{"", "Anna", "a b", "../x", strings.Repeat("a", 33), "-x"} {
		if _, err := s.Add(bad); err != ErrBadName {
			t.Fatalf("name %q accepted", bad)
		}
	}
}

// THE CONSEQUENCE: a reset or a removal ends the member's sessions at once; a logout ends one session; an expired
// session is refused; another member's session is untouched.
func TestFamily_SessionsEndOnResetRemoveLogout(t *testing.T) {
	s, _ := testStore(t)
	now := time.Date(2026, 10, 2, 9, 0, 0, 0, time.UTC)
	s.SetClock(func() time.Time { return now })
	s.Add("anna")
	s.Add("bela")
	a1, _ := s.NewSession("anna")
	a2, _ := s.NewSession("anna")
	b1, _ := s.NewSession("bela")
	h1, _ := s.NewSession("")
	for _, id := range []string{a1, a2, b1, h1} {
		if _, ok := s.Valid(id); !ok {
			t.Fatalf("fresh session %s refused", id)
		}
	}
	if _, err := s.Reset("anna"); err != nil {
		t.Fatal(err)
	}
	if _, ok := s.Valid(a1); ok {
		t.Fatal("a reset password must end the member's earlier sessions")
	}
	if _, ok := s.Valid(b1); !ok {
		t.Fatal("another member's session must survive")
	}
	s.EndSession(b1)
	if _, ok := s.Valid(b1); ok {
		t.Fatal("logout must end the session")
	}
	b2, _ := s.NewSession("bela")
	s.Remove("bela")
	if _, ok := s.Valid(b2); ok {
		t.Fatal("a removed member's session must end")
	}
	if _, err := s.NewSession("bela"); err != ErrNoMember {
		t.Fatal("no session for a removed member")
	}
	now = now.Add(SessionLife + time.Minute)
	if _, ok := s.Valid(h1); ok {
		t.Fatal("an expired session must be refused")
	}
}

// A gen bump survives a reopen: an OLD session read back from disk after a reset is still refused.
func TestFamily_ResetHoldsAcrossReopen(t *testing.T) {
	s, dir := testStore(t)
	s.Add("anna")
	id, _ := s.NewSession("anna")
	s.Reset("anna")
	s2, _ := Open(dir)
	if _, ok := s2.Valid(id); ok {
		t.Fatal("after a reopen the pre-reset session must still be refused")
	}
}

func TestFamily_UnreadableFileIsAnError(t *testing.T) {
	dir := t.TempDir()
	os.WriteFile(filepath.Join(dir, "family.json"), []byte("{not json"), 0o600)
	if _, err := Open(dir); err == nil {
		t.Fatal("an unreadable list must be an error, never an empty list")
	}
}

func TestFamily_NilStoreAnswersNobody(t *testing.T) {
	var s *Store
	if s.Verify("a", "b") || len(s.Names()) != 0 {
		t.Fatal("nil store")
	}
	if _, ok := s.Valid("x"); ok {
		t.Fatal("nil store valid")
	}
}