// Copyright (C) 2017-2023 Internet Systems Consortium, Inc. ("ISC")
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

#include <config.h>

#include <dhcp/dhcp4.h>
#include <dhcp/option_custom.h>
#include <dhcp/option_space.h>
#include <dhcpsrv/network.h>
#include <boost/pointer_cast.hpp>

using namespace isc::asiolink;
using namespace isc::data;
using namespace isc::util;

namespace isc {
namespace dhcp {

void
Network::RelayInfo::addAddress(const asiolink::IOAddress& addr) {
    if (containsAddress(addr)) {
        isc_throw (BadValue, "RelayInfo already contains address: "
                   << addr.toText());
    }

    addresses_.push_back(addr);
}

bool
Network::RelayInfo::hasAddresses() const {
    return (!addresses_.empty());
}

bool
Network::RelayInfo::containsAddress(const asiolink::IOAddress& addr) const {
    auto const& index = addresses_.get<IOAddressListSetTag>();
    return (index.find(addr) != index.end());
}

const IOAddressList&
Network::RelayInfo::getAddresses() const {
    return (addresses_);
}

void
Network::addRelayAddress(const asiolink::IOAddress& addr) {
    relay_.addAddress(addr);
}

bool
Network::hasRelays() const {
    return (relay_.hasAddresses());
}

bool
Network::hasRelayAddress(const asiolink::IOAddress& addr) const {
    return (relay_.containsAddress(addr));
}

const IOAddressList&
Network::getRelayAddresses() const {
    return (relay_.getAddresses());
}

bool
Network::clientSupported(const isc::dhcp::ClientClasses& classes) const {
    if (client_class_.empty()) {
        // There is no class defined for this network, so we do
        // support everyone.
        return (true);
    }

    return (classes.contains(client_class_));
}

void
Network::allowClientClass(const isc::dhcp::ClientClass& class_name) {
    client_class_ = class_name;
}

void
Network::requireClientClass(const isc::dhcp::ClientClass& class_name) {
    if (!required_classes_.contains(class_name)) {
        required_classes_.insert(class_name);
    }
}

const ClientClasses&
Network::getRequiredClasses() const {
    return (required_classes_);
}

Optional<IOAddress>
Network::getGlobalProperty(Optional<IOAddress> property,
                           const int global_index,
                           const int /*min_index*/,
                           const int /*max_index*/) const {
    if ((global_index >= 0) && fetch_globals_fn_) {
        ConstCfgGlobalsPtr globals = fetch_globals_fn_();
        if (globals) {
            ConstElementPtr global_param = globals->get(global_index);
            if (global_param) {
                std::string global_str = global_param->stringValue();
                if (!global_str.empty()) {
                    return (IOAddress(global_str));
                }
            }
        }
    }
    return (property);
}

ElementPtr
Network::toElement() const {
    ElementPtr map = Element::createMap();

    // Set user-context
    contextToElement(map);

    // Set interface
    if (!iface_name_.unspecified()) {
        map->set("interface", Element::create(iface_name_.get()));
    }

    ElementPtr relay_map = Element::createMap();
    ElementPtr address_list = Element::createList();
    const IOAddressList addresses = getRelayAddresses();
    for (auto address = addresses.begin(); address != addresses.end(); ++address) {
        address_list->add(Element::create((*address).toText()));
    }

    relay_map->set("ip-addresses", address_list);
    map->set("relay", relay_map);

    // Set client-class
    if (!client_class_.unspecified()) {
        map->set("client-class", Element::create(client_class_.get()));
    }

    // Set require-client-classes
    const ClientClasses& classes = getRequiredClasses();
    if (!classes.empty()) {
        ElementPtr class_list = Element::createList();
        for (ClientClasses::const_iterator it = classes.cbegin();
             it != classes.cend(); ++it) {
            class_list->add(Element::create(*it));
        }
        map->set("require-client-classes", class_list);
    }

    // T1, T2, and Valid are optional for SharedNetworks, and
    // T1 and T2 are optional for Subnet4 thus we will only
    // output them if they are marked as specified.
    if (!t1_.unspecified()) {
        map->set("renew-timer",
                 Element::create(static_cast<long long>(t1_.get())));
    }

    // Set rebind-timer
    if (!t2_.unspecified()) {
        map->set("rebind-timer",
                 Element::create(static_cast<long long>(t2_.get())));
    }

    // Set valid-lifetime
    if (!valid_.unspecified()) {
        map->set("valid-lifetime",
                 Element::create(static_cast<long long>(valid_.get())));
        map->set("min-valid-lifetime",
                 Element::create(static_cast<long long>(valid_.getMin())));
        map->set("max-valid-lifetime",
                 Element::create(static_cast<long long>(valid_.getMax())));
    }

    // Set reservations-global
    if (!reservations_global_.unspecified()) {
        map->set("reservations-global",
                 Element::create(reservations_global_.get()));
    }

    // Set reservations-in-subnet
    if (!reservations_in_subnet_.unspecified()) {
        map->set("reservations-in-subnet",
                 Element::create(reservations_in_subnet_.get()));
    }

    // Set reservations-out-of-pool
    if (!reservations_out_of_pool_.unspecified()) {
        map->set("reservations-out-of-pool",
                 Element::create(reservations_out_of_pool_.get()));
    }

    // Set options
    ConstCfgOptionPtr opts = getCfgOption();
    map->set("option-data", opts->toElement());

    // Output calculate-tee-times and percentages if calculation is enabled.
    if (!calculate_tee_times_.unspecified()) {
        map->set("calculate-tee-times", Element::create(calculate_tee_times_));
    }

    if (!t1_percent_.unspecified()) {
        map->set("t1-percent", Element::create(t1_percent_));
    }

    if (!t2_percent_.unspecified()) {
        map->set("t2-percent", Element::create(t2_percent_));
    }

    if (!ddns_send_updates_.unspecified()) {
        map->set("ddns-send-updates", Element::create(ddns_send_updates_));
    }

    if (!ddns_override_no_update_.unspecified()) {
        map->set("ddns-override-no-update", Element::create(ddns_override_no_update_));
    }

    if (!ddns_override_client_update_.unspecified()) {
        map->set("ddns-override-client-update", Element::create(ddns_override_client_update_));
    }

    if (!ddns_replace_client_name_mode_.unspecified()) {
        map->set("ddns-replace-client-name",
                  Element::create(D2ClientConfig::
                                  replaceClientNameModeToString(ddns_replace_client_name_mode_)));
    }

    if (!ddns_generated_prefix_.unspecified()) {
        map->set("ddns-generated-prefix", Element::create(ddns_generated_prefix_));
    }

    if (!ddns_qualifying_suffix_.unspecified()) {
        map->set("ddns-qualifying-suffix", Element::create(ddns_qualifying_suffix_));
    }

    if (!hostname_char_set_.unspecified()) {
        map->set("hostname-char-set", Element::create(hostname_char_set_));
    }

    if (!hostname_char_replacement_.unspecified()) {
        map->set("hostname-char-replacement", Element::create(hostname_char_replacement_));
    }

    if (!store_extended_info_.unspecified()) {
        map->set("store-extended-info", Element::create(store_extended_info_));
    }

    if (!cache_threshold_.unspecified()) {
        map->set("cache-threshold", Element::create(cache_threshold_));
    }

    if (!cache_max_age_.unspecified()) {
        map->set("cache-max-age",
                 Element::create(static_cast<long long>(cache_max_age_)));
    }

    if (!ddns_update_on_renew_.unspecified()) {
        map->set("ddns-update-on-renew", Element::create(ddns_update_on_renew_));
    }

    if (!ddns_use_conflict_resolution_.unspecified()) {
        map->set("ddns-use-conflict-resolution", Element::create(ddns_use_conflict_resolution_));
    }

    if (!allocator_type_.unspecified()) {
        map->set("allocator", Element::create(allocator_type_));
    }

    return (map);
}

void
Network4::setSiaddr(const Optional<IOAddress>& siaddr) {
    if (!siaddr.get().isV4()) {
        isc_throw(BadValue, "Can't set siaddr to non-IPv4 address "
                  << siaddr);
    }
    siaddr_ = siaddr;
}

void
Network4::setSname(const Optional<std::string>& sname) {
    sname_ = sname;
}

void
Network4::setFilename(const Optional<std::string>& filename) {
    filename_ = filename;
}

ElementPtr
Network4::toElement() const {
    ElementPtr map = Network::toElement();

    // Set match-client-id
    if (!match_client_id_.unspecified()) {
        map->set("match-client-id", Element::create(match_client_id_.get()));
    }

    // Set authoritative
    if (!authoritative_.unspecified()) {
        map->set("authoritative", Element::create(authoritative_.get()));
    }

    // Set next-server
    if (!siaddr_.unspecified()) {
        map->set("next-server", Element::create(siaddr_.get().toText()));
    }

    // Set server-hostname
    if (!sname_.unspecified()) {
        map->set("server-hostname", Element::create(sname_.get()));
    }

    // Set boot-file-name
    if (!filename_.unspecified()) {
        map->set("boot-file-name",Element::create(filename_.get()));
    }

    return (map);
}

IOAddress
Network4::getServerId() const {
    try {
        OptionCustomPtr opt_server_id = boost::dynamic_pointer_cast<OptionCustom>
            (cfg_option_->get(DHCP4_OPTION_SPACE, DHO_DHCP_SERVER_IDENTIFIER).option_);
        if (opt_server_id) {
            return (opt_server_id->readAddress());
        }
    } catch (const std::exception&) {
        // Ignore any exceptions and simply return empty buffer.
    }

    return (IOAddress::IPV4_ZERO_ADDRESS());
}

ElementPtr
Network6::toElement() const {
    ElementPtr map = Network::toElement();

    // Set preferred-lifetime
    if (!preferred_.unspecified()) {
        map->set("preferred-lifetime",
                 Element::create(static_cast<long long>(preferred_.get())));
        map->set("min-preferred-lifetime",
                 Element::create(static_cast<long long>(preferred_.getMin())));
        map->set("max-preferred-lifetime",
                 Element::create(static_cast<long long>(preferred_.getMax())));
    }

    // Set interface-id
    if (interface_id_) {
        std::vector<uint8_t> bin = interface_id_->getData();
        std::string ifid;
        ifid.resize(bin.size());
        if (!bin.empty()) {
            std::memcpy(&ifid[0], &bin[0], bin.size());
        }
        map->set("interface-id", Element::create(ifid));
    }

    // Set rapid-commit
    if (!rapid_commit_.unspecified()) {
        map->set("rapid-commit", Element::create(rapid_commit_.get()));
    }

    // Set pd-allocator
    if (!pd_allocator_type_.unspecified()) {
        map->set("pd-allocator", Element::create(pd_allocator_type_));
    }

    return (map);
}

} // end of namespace isc::dhcp
} // end of namespace isc