utf8/win1251 converter

enum encode_mode {
    UTFtoWIN,
    WINtoUTF
};

std::string encoder(std::string text_to_encode, int encode_mode) {
    BSTR bstrWide;
    int length;
    char *text = new char[text_to_encode.size() + 1];
    for (int i = 0; i < text_to_encode.size(); i++) {
        text[i] = text_to_encode[i];
    }
    text[text_to_encode.size()] = '\0';
    if (encode_mode == encode_mode::UTFtoWIN) {
        length = MultiByteToWideChar(CP_UTF8, 0, text, strlen(text), NULL, NULL);
        bstrWide = SysAllocStringLen(NULL, length);
        MultiByteToWideChar(CP_UTF8, 0, text, strlen(text), bstrWide, length);
        length = WideCharToMultiByte(1251, 0, bstrWide, -1, NULL, 0, NULL, NULL);
        char *text_1251 = new char[length];
        WideCharToMultiByte(1251, 0, bstrWide, -1, text_1251, length, NULL, NULL);
        SysFreeString(bstrWide);
        text_to_encode.clear();
        for (int i = 0; i < strlen(text_1251); i++) {
            text_to_encode += text_1251[i];
        }
        delete[]text_1251;
    }
    else if (encode_mode == encode_mode::WINtoUTF) {
        length = MultiByteToWideChar(1251, 0, text, strlen(text), NULL, NULL);
        bstrWide = SysAllocStringLen(NULL, length);
        MultiByteToWideChar(1251, 0, text, strlen(text), bstrWide, length);
        length = WideCharToMultiByte(CP_UTF8, 0, bstrWide, -1, NULL, 0, NULL, NULL);
        char *text_u8 = new char[length];
        WideCharToMultiByte(CP_UTF8, 0, bstrWide, -1, text_u8, length, NULL, NULL);
        SysFreeString(bstrWide);
        text_to_encode.clear();
        for (int i = 0; i < strlen(text_u8); i++) {
            text_to_encode += text_u8[i];
        }
        delete[]text_u8;
    }
    delete[]text;
    return text_to_encode;
}