"sync"
	"testing"
	"time"

	"gorm.io/gorm"
	. "gorm.io/gorm/utils/tests"
)

func TestPreparedStmt(t *testing.T) {
	tx := DB.Session(&gorm.Session{PrepareStmt: true})

	if _, ok := tx.ConnPool.(*gorm.PreparedStmtDB); !ok {
		t.Fatalf("should assign PreparedStatement Manager back to database when using PrepareStmt mode")
	}

	ctx, cancel := context.WithTimeout(context.Background(), 500*time.Millisecond)
	defer cancel()

}

// GetSerializer get serializer
func GetSerializer(name string) (serializer SerializerInterface, ok bool) {
	v, ok := serializerMap.Load(strings.ToLower(name))
	if ok {
		serializer, ok = v.(SerializerInterface)
	}
	return serializer, ok
}

func init() {
	RegisterSerializer("json", JSONSerializer{})
	RegisterSerializer("unixtime", UnixSecondSerializer{})

		builder.WriteString("OFFSET ")
		builder.AddVar(builder, limit.Offset)
	}
}

// MergeClause merge order by clauses
func (limit Limit) MergeClause(clause *Clause) {
	clause.Name = ""

	if v, ok := clause.Expression.(Limit); ok {
		if (limit.Limit == nil || *limit.Limit == 0) && v.Limit != nil {
			limit.Limit = v.Limit
		}

		if limit.Offset == 0 && v.Offset > 0 {
			limit.Offset = v.Offset
		} else if limit.Offset < 0 {

		stmt              = db.Statement
		resetBuildClauses bool
	)

	if len(stmt.BuildClauses) == 0 {
		stmt.BuildClauses = p.Clauses
		resetBuildClauses = true
	}

	if optimizer, ok := db.Statement.Dest.(StatementModifier); ok {
		optimizer.ModifyStatement(stmt)
	}

	// assign model values
	if stmt.Model == nil {
		stmt.Model = stmt.Dest
	} else if stmt.Dest == nil {
		stmt.Dest = stmt.Model
	}

	}

	if err = tx.First(&User{}, "name = ?", user1.Name).Error; err != nil {
		t.Fatalf("Should find saved record, but got %v", err)
	}

	if sqlTx, ok := tx.Statement.ConnPool.(gorm.TxCommitter); !ok || sqlTx == nil {
		t.Fatalf("Should return the underlying sql.Tx")
	}

	tx.Rollback()

	if err = db.First(&User{}, "name = ?", "transaction").Error; err == nil {

	createCallback.Remove("c1")
	if ok, msg := assertCallbacks(createCallback, []string{"c3", "c4", "c2"}); !ok {
		t.Errorf("callbacks tests failed, got %v", msg)
	}

	createCallback.Remove("c4")
	if ok, msg := assertCallbacks(createCallback, []string{"c3", "c2"}); !ok {
		t.Errorf("callbacks tests failed, got %v", msg)
	}

	createCallback.Remove("c2")

	yval := reflect.ValueOf(y)
	if xval.Kind() == reflect.Ptr && xval.IsNil() ||
		yval.Kind() == reflect.Ptr && yval.IsNil() {
		return false
	}

	if valuer, ok := x.(driver.Valuer); ok {
		x, _ = valuer.Value()
	}
	if valuer, ok := y.(driver.Valuer); ok {
		y, _ = valuer.Value()
	}
	return reflect.DeepEqual(x, y)
}

func ToString(value interface{}) string {
	switch v := value.(type) {
	case string:

				f.TagSettings = schema.ParseTagSetting(f.Tag.Get("gorm"), ";")
			} else {
				f.TagSettings = map[string]string{}
			}
		}

		parsedField, ok := s.FieldsByDBName[f.DBName]
		if !ok {
			parsedField, ok = s.FieldsByName[f.Name]
		}

		if !ok {
			t.Errorf("schema %v failed to look up field with name %v", s, f.Name)
		} else {

		default:
			rv := reflect.ValueOf(v)
			if v == nil || !rv.IsValid() || rv.Kind() == reflect.Ptr && rv.IsNil() {
				vars[idx] = nullStr
			} else if valuer, ok := v.(driver.Valuer); ok {
				v, _ = valuer.Value()
				convertParams(v, idx)
			} else if rv.Kind() == reflect.Ptr && !rv.IsZero() {
				convertParams(reflect.Indirect(rv).Interface(), idx)
			} else if isNumeric(rv.Kind()) {

	if sqldb, ok := db.ConnPool.(*sql.DB); ok {
		return sqldb, nil
	}

	if dbConnector, ok := db.ConnPool.(GetDBConnector); ok && dbConnector != nil {
		return dbConnector.GetDBConn()
	}

	return nil, ErrInvalidDB
}

func (db *PreparedStmtDB) Close() {
	db.Mux.Lock()
	defer db.Mux.Unlock()

	for _, query := range db.PreparedSQL {
		if stmt, ok := db.Stmts[query]; ok {