// Copyright (C) 2019-2020 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 <dhcpsrv/triplet.h>
#include <dhcpsrv/parsers/base_network_parser.h>
#include <dhcpsrv/parsers/reservation_modes_parser.h>
#include <util/optional.h>
#include <util/strutil.h>

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

namespace isc {
namespace dhcp {

const Triplet<uint32_t>
BaseNetworkParser::parseLifetime(const ConstElementPtr& scope,
                                 const std::string& name) {
    // Initialize as some compilers complain otherwise.
    uint32_t value = 0;
    bool has_value = false;
    uint32_t min_value = 0;
    bool has_min = false;
    uint32_t max_value = 0;
    bool has_max = false;
    if (scope->contains(name)) {
        value = getInteger(scope, name);
        has_value = true;
    }
    if (scope->contains("min-" + name)) {
        min_value = getInteger(scope, "min-" + name);
        has_min = true;
    }
    if (scope->contains("max-" + name)) {
        max_value = getInteger(scope, "max-" + name);
        has_max = true;
    }
    if (!has_value && !has_min && !has_max) {
        return (Triplet<uint32_t>());
    }
    if (has_value) {
        if (!has_min && !has_max) {
            // default only.
            min_value = value;
            max_value = value;
        } else if (!has_min) {
            // default and max.
            min_value = value;
        } else if (!has_max) {
            // default and min.
            max_value = value;
        }
    } else if (has_min) {
        // min only.
        if (!has_max) {
            value = min_value;
            max_value = min_value;
        } else {
            // min and max.
            isc_throw(DhcpConfigError, "have min-" << name << " and max-"
                      << name << " but no " << name << " (default) in "
                      << scope->getPosition());
        }
    } else {
        // max only.
        min_value = max_value;
        value = max_value;
    }
    // Check that min <= max.
    if (min_value > max_value) {
        if (has_min && has_max) {
            isc_throw(DhcpConfigError, "the value of min-" << name << " ("
                      << min_value << ") is not less than max-" << name << " ("
                      << max_value << ")");
        } else if (has_min) {
            // Only min and default so min > default.
            isc_throw(DhcpConfigError, "the value of min-" << name << " ("
                      << min_value << ") is not less than (default) " << name
                      << " (" << value << ")");
        } else {
            // Only default and max so default > max.
            isc_throw(DhcpConfigError, "the value of (default) " << name
                      << " (" << value << ") is not less than max-" << name
                      << " (" << max_value << ")");
        }
    }
    // Check that value is between min and max.
    if ((value < min_value) || (value > max_value)) {
        isc_throw(DhcpConfigError, "the value of (default) " << name << " ("
                  << value << ") is not between min-" << name << " ("
                  << min_value << ") and max-" << name << " ("
                  << max_value << ")");
    }
    return (Triplet<uint32_t>(min_value, value, max_value));
}

void
BaseNetworkParser::parseCommon(const ConstElementPtr& network_data,
                               NetworkPtr& network) {
    bool has_renew = network_data->contains("renew-timer");
    bool has_rebind = network_data->contains("rebind-timer");
    int64_t renew = -1;
    int64_t rebind = -1;

    if (has_renew) {
        renew = getInteger(network_data, "renew-timer");
        if (renew < 0) {
            isc_throw(DhcpConfigError, "the value of renew-timer" << " ("
                      << renew << ") must be a positive number");
        }
        network->setT1(renew);
    }

    if (has_rebind) {
        rebind = getInteger(network_data, "rebind-timer");
        if (rebind < 0) {
            isc_throw(DhcpConfigError, "the value of rebind-timer" << " ("
                      << rebind << ") must be a positive number");
        }
        network->setT2(rebind);
    }

    if (has_renew && has_rebind && (renew > rebind)) {
        isc_throw(DhcpConfigError, "the value of renew-timer" << " (" << renew
                  << ") is greater than the value of rebind-timer" << " ("
                  << rebind << ")");
    }

    network->setValid(parseLifetime(network_data, "valid-lifetime"));

    if (network_data->contains("store-extended-info")) {
        network->setStoreExtendedInfo(getBoolean(network_data,
                                                 "store-extended-info"));
    }
}

void
BaseNetworkParser::parseTeePercents(const ConstElementPtr& network_data,
                                    NetworkPtr& network) {
    bool calculate_tee_times = network->getCalculateTeeTimes();
    if (network_data->contains("calculate-tee-times")) {
        calculate_tee_times = getBoolean(network_data, "calculate-tee-times");
        network->setCalculateTeeTimes(calculate_tee_times);
    }

    Optional<double> t2_percent;
    if (network_data->contains("t2-percent")) {
        t2_percent = getDouble(network_data, "t2-percent");
    }

    Optional<double> t1_percent;
    if (network_data->contains("t1-percent")) {
        t1_percent = getDouble(network_data, "t1-percent");
    }
    if (calculate_tee_times) {
        if (!t2_percent.unspecified() && ((t2_percent.get() <= 0.0) ||
                                          (t2_percent.get() >= 1.0))) {
            isc_throw(DhcpConfigError, "t2-percent:  " << t2_percent.get()
                      << " is invalid, it must be greater than 0.0 and less than 1.0");
        }

        if (!t1_percent.unspecified() && ((t1_percent.get() <= 0.0) ||
                                          (t1_percent.get() >= 1.0))) {
            isc_throw(DhcpConfigError, "t1-percent:  " << t1_percent.get()
                      << " is invalid it must be greater than 0.0 and less than 1.0");
        }

        if (!t1_percent.unspecified() && !t2_percent.unspecified() &&
            (t1_percent.get() >= t2_percent.get())) {
            isc_throw(DhcpConfigError, "t1-percent:  " << t1_percent.get()
                      << " is invalid, it must be less than t2-percent: "
                      << t2_percent.get());
        }
    }

    network->setT2Percent(t2_percent);
    network->setT1Percent(t1_percent);
}

void
BaseNetworkParser::parseCacheParams(const ConstElementPtr& network_data,
                                    NetworkPtr& network) {
    if (network_data->contains("cache-threshold")) {
        double cache_threshold = getDouble(network_data, "cache-threshold");
        if ((cache_threshold <= 0.0) || (cache_threshold >= 1.0)) {
            isc_throw(DhcpConfigError, "cache-threshold: " << cache_threshold
                      << " is invalid, it must be greater than 0.0 and less than 1.0");
        }
        network->setCacheThreshold(cache_threshold);
    }

    if (network_data->contains("cache-max-age")) {
        network->setCacheMaxAge(getInteger(network_data, "cache-max-age"));
    }
}

void
BaseNetworkParser::parseHostReservationMode(const data::ConstElementPtr& network_data,
                                            NetworkPtr& network) {
    if (network_data->contains("reservation-mode")) {
        bool found = false;
        if (network_data->contains("reservations-out-of-pool") ||
            network_data->contains("reservations-in-subnet") ||
            network_data->contains("reservations-global")) {
            found = true;
        }
        if (found) {
            isc_throw(DhcpConfigError, "invalid use of both 'reservation-mode'"
                                       " and one of 'reservations-out-of-pool'"
                                       " , 'reservations-in-subnet' or"
                                       " 'reservations-global' parameters");
        }
        try {
            std::string hr_mode = getString(network_data, "reservation-mode");
            network->setHostReservationMode(Network::hrModeFromString(hr_mode));
        } catch (const BadValue& ex) {
            isc_throw(DhcpConfigError, "invalid reservation-mode parameter: "
                      << ex.what() << " (" << getPosition("reservation-mode",
                                                          network_data) << ")");
        }
    }
}

void
BaseNetworkParser::parseHostReservationModes(const data::ConstElementPtr& network_data,
                                             NetworkPtr& network) {
    bool found = false;
    if (network_data->contains("reservations-out-of-pool") ||
        network_data->contains("reservations-in-subnet") ||
        network_data->contains("reservations-global")) {
        found = true;
    }
    if (found) {
        if (network_data->contains("reservation-mode")) {
            isc_throw(DhcpConfigError, "invalid use of both 'reservation-mode'"
                                       " and one of 'reservations-out-of-pool'"
                                       " , 'reservations-in-subnet' or"
                                       " 'reservations-global' parameters");
        }
    } else {
        return;
    }
    try {
        HostReservationModesParser parser;
        Network::HRMode flags = parser.parse(network_data);
        network->setHostReservationMode(flags);
    } catch (const BadValue& ex) {
        isc_throw(DhcpConfigError, "invalid parameter: " << ex.what());
    }
}

void
BaseNetworkParser::parseDdnsParams(const data::ConstElementPtr& network_data,
                                   NetworkPtr& network) {

    if (network_data->contains("ddns-send-updates")) {
        network->setDdnsSendUpdates(getBoolean(network_data, "ddns-send-updates"));
    }

    if (network_data->contains("ddns-override-no-update")) {
        network->setDdnsOverrideNoUpdate(getBoolean(network_data, "ddns-override-no-update"));
    }

    if (network_data->contains("ddns-override-client-update")) {
        network->setDdnsOverrideClientUpdate(getBoolean(network_data, "ddns-override-client-update"));
    }

    if (network_data->contains("ddns-replace-client-name")) {
        network->setDdnsReplaceClientNameMode(getAndConvert<D2ClientConfig::ReplaceClientNameMode,
                                                            D2ClientConfig::stringToReplaceClientNameMode>
                                                            (network_data, "ddns-replace-client-name",
                                                             "ReplaceClientName mode"));
    }

    if (network_data->contains("ddns-generated-prefix")) {
        network->setDdnsGeneratedPrefix(getString(network_data, "ddns-generated-prefix"));
    }

    if (network_data->contains("ddns-qualifying-suffix")) {
        network->setDdnsQualifyingSuffix(getString(network_data, "ddns-qualifying-suffix"));
    }

    std::string hostname_char_set;
    if (network_data->contains("hostname-char-set")) {
        hostname_char_set = getString(network_data, "hostname-char-set");
        network->setHostnameCharSet(hostname_char_set);
    }

    std::string hostname_char_replacement;
    if (network_data->contains("hostname-char-replacement")) {
        hostname_char_replacement = getString(network_data, "hostname-char-replacement");
        network->setHostnameCharReplacement(hostname_char_replacement);
    }

    // We need to validate santizer values here so we can detect problems and
    // cause a configuration.  We don't retain the compilation because it's not
    // something we can inherit.
    if (!hostname_char_set.empty()) {
        try {
            str::StringSanitizerPtr sanitizer(new str::StringSanitizer(hostname_char_set,
                                                                       hostname_char_replacement));
        } catch (const std::exception& ex) {
            isc_throw(BadValue, "hostname-char-set '" << hostname_char_set
                      << "' is not a valid regular expression");
        }
    }

    if (network_data->contains("ddns-update-on-renew")) {
        network->setDdnsUpdateOnRenew(getBoolean(network_data, "ddns-update-on-renew"));
    }

    if (network_data->contains("ddns-use-conflict-resolution")) {
        network->setDdnsUseConflictResolution(getBoolean(network_data, "ddns-use-conflict-resolution"));
    }
}

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