//    OpenVPN -- An application to securely tunnel IP networks
//               over a single port, with support for SSL/TLS-based
//               session authentication and key exchange,
//               packet encryption, packet authentication, and
//               packet compression.
//
//    Copyright (C) 2012- OpenVPN Inc.
//
//    SPDX-License-Identifier: MPL-2.0 OR AGPL-3.0-only WITH openvpn3-openssl-exception
//

#ifndef OPENVPN_OPTIONS_SERVPUSH_H
#define OPENVPN_OPTIONS_SERVPUSH_H

#include <string>
#include <sstream>
#include <ostream>
#include <vector>
#include <utility> // for std::move

#include <openvpn/common/exception.hpp>
#include <openvpn/common/options.hpp>
#include <openvpn/common/jsonlib.hpp>

#ifdef HAVE_JSON
#include <openvpn/common/jsonhelper.hpp>
#endif

namespace openvpn {
class ServerPushList : public std::vector<std::string>
{
  public:
    void parse(const std::string &opt_name, const OptionList &opt)
    {
        const auto *push = opt.get_index_ptr(opt_name);
        if (push)
        {
            reserve(size() + push->size());
            for (auto &i : *push)
            {
                const Option &o = opt[i];
                o.touch();
                push_back(o.get(1, 512));
            }
        }
    }

#ifdef HAVE_JSON
    // Parse JSON representation of a push list.
    // Each push list array element can be one of:
    // 1. simple JSON string,
    // 2. dictionary containing an "item" string, or
    // 3. dictionary containing an "item" array of strings.
    void parse(const std::string &title, const Json::Value &push_list) // push_list is JSON array
    {
        reserve(16); // arbitrary, just a guess
        const auto &ja = json::cast_array(push_list, false, title).asArray();
        for (size_t i = 0; i < ja.size(); ++i)
        {
            const Json::Value &jv = ja[i];
            if (jv.isString())
                push_back(jv.asStringRef());
            else if (jv.isObject())
            {
                const Json::Value &ji = jv["item"];
                if (ji.isString())
                    push_back(ji.asStringRef());
                else if (ji.isArray())
                {
                    const auto &ia = ji.asArray();
                    for (size_t j = 0; j < ia.size(); ++j)
                    {
                        const Json::Value &iv = ia[j];
                        if (iv.isString())
                            push_back(iv.asStringRef());
                        else
                            throw json::json_parse(json::fmt_name(i, title) + " object contains 'item' array that includes non-string element at index=" + std::to_string(j));
                    }
                }
                else
                    throw json::json_parse(json::fmt_name(i, title) + " object must contain 'item' string or array");
            }
            else
                throw json::json_parse(json::fmt_name(i, title) + " must be of type string or object");
        }
    }
#endif

    void extend(const std::vector<std::string> &other)
    {
        reserve(size() + other.size());
        for (auto &e : other)
            push_back(e);
    }

    // do a roundtrip to csv and back to OptionList
    OptionList to_option_list() const
    {
        std::ostringstream os;
        output_csv(os);
        return OptionList::parse_from_csv_static(os.str(), nullptr);
    }

    void output_csv(std::ostream &os) const
    {
        for (auto &e : *this)
        {
            os << ',';
            output_arg(e, os);
        }
    }

    static void output_arg(const std::string &e, std::ostream &os)
    {
        const bool must_quote = (e.find_first_of(',') != std::string::npos);
        Option::escape_string(os, e, must_quote);
    }
};
} // namespace openvpn

#endif
