// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright OpenBMC Authors
// SPDX-FileCopyrightText: Copyright 2020 Intel Corporation
#include "subscription.hpp"

#include "dbus_singleton.hpp"
#include "event_log.hpp"
#include "event_logs_object_type.hpp"
#include "event_matches_filter.hpp"
#include "event_service_store.hpp"
#include "filter_expr_executor.hpp"
#include "heartbeat_messages.hpp"
#include "http_client.hpp"
#include "http_response.hpp"
#include "logging.hpp"
#include "server_sent_event.hpp"
#include "ssl_key_handler.hpp"
#include "telemetry_readings.hpp"
#include "utils/time_utils.hpp"

#include <boost/asio/error.hpp>
#include <boost/asio/io_context.hpp>
#include <boost/asio/steady_timer.hpp>
#include <boost/beast/http/field.hpp>
#include <boost/beast/http/fields.hpp>
#include <boost/beast/http/verb.hpp>
#include <boost/system/errc.hpp>
#include <boost/url/format.hpp>
#include <boost/url/url_view_base.hpp>
#include <nlohmann/json.hpp>

#include <algorithm>
#include <chrono>
#include <cstdint>
#include <format>
#include <functional>
#include <memory>
#include <span>
#include <string>
#include <string_view>
#include <utility>
#include <vector>

namespace redfish
{

Subscription::Subscription(
    std::shared_ptr<persistent_data::UserSubscription> userSubIn,
    const boost::urls::url_view_base& url, boost::asio::io_context& ioc) :
    userSub{std::move(userSubIn)},
    policy(std::make_shared<crow::ConnectionPolicy>()), hbTimer(ioc)
{
    userSub->destinationUrl = url;
    client.emplace(ioc, policy);
    // Subscription constructor
    policy->invalidResp = retryRespHandler;
}

Subscription::Subscription(crow::sse_socket::Connection& connIn) :
    userSub{std::make_shared<persistent_data::UserSubscription>()},
    sseConn(&connIn), hbTimer(crow::connections::systemBus->get_io_context())
{}

// callback for subscription sendData
void Subscription::resHandler(const std::shared_ptr<Subscription>& /*self*/,
                              const crow::Response& res)
{
    BMCWEB_LOG_DEBUG("Response handled with return code: {}", res.resultInt());

    if (!client)
    {
        BMCWEB_LOG_ERROR(
            "Http client wasn't filled but http client callback was called.");
        return;
    }

    if (userSub->retryPolicy != "TerminateAfterRetries")
    {
        return;
    }
    if (client->isTerminated())
    {
        hbTimer.cancel();
        if (deleter)
        {
            BMCWEB_LOG_INFO("Subscription {} is deleted after MaxRetryAttempts",
                            userSub->id);
            deleter();
        }
    }
}

void Subscription::sendHeartbeatEvent()
{
    // send the heartbeat message
    nlohmann::json eventMessage = messages::redfishServiceFunctional();
    eventMessage["EventTimestamp"] = time_utils::getDateTimeOffsetNow().first;
    eventMessage["OriginOfCondition"] =
        std::format("/redfish/v1/EventService/Subscriptions/{}", userSub->id);
    eventMessage["MemberId"] = "0";

    nlohmann::json::array_t eventRecord;
    eventRecord.emplace_back(std::move(eventMessage));

    nlohmann::json msgJson;
    msgJson["@odata.type"] = "#Event.v1_4_0.Event";
    msgJson["Name"] = "Heartbeat";
    msgJson["Events"] = std::move(eventRecord);

    std::string strMsg =
        msgJson.dump(2, ' ', true, nlohmann::json::error_handler_t::replace);

    // Note, eventId here is always zero, because this is a a per subscription
    // event and doesn't have an "ID"
    uint64_t eventId = 0;
    sendEventToSubscriber(eventId, std::move(strMsg));
}

void Subscription::scheduleNextHeartbeatEvent()
{
    hbTimer.expires_after(std::chrono::minutes(userSub->hbIntervalMinutes));
    hbTimer.async_wait(
        std::bind_front(&Subscription::onHbTimeout, this, weak_from_this()));
}

void Subscription::heartbeatParametersChanged()
{
    hbTimer.cancel();

    if (userSub->sendHeartbeat)
    {
        scheduleNextHeartbeatEvent();
    }
}

void Subscription::onHbTimeout(const std::weak_ptr<Subscription>& weakSelf,
                               const boost::system::error_code& ec)
{
    if (ec == boost::asio::error::operation_aborted)
    {
        BMCWEB_LOG_DEBUG("heartbeat timer async_wait is aborted");
        return;
    }
    if (ec == boost::system::errc::operation_canceled)
    {
        BMCWEB_LOG_DEBUG("heartbeat timer async_wait canceled");
        return;
    }
    if (ec)
    {
        BMCWEB_LOG_CRITICAL("heartbeat timer async_wait failed: {}", ec);
        return;
    }

    std::shared_ptr<Subscription> self = weakSelf.lock();
    if (!self)
    {
        BMCWEB_LOG_CRITICAL("onHbTimeout failed on Subscription");
        return;
    }

    // Timer expired.
    sendHeartbeatEvent();

    // reschedule heartbeat timer
    scheduleNextHeartbeatEvent();
}

bool Subscription::sendEventToSubscriber(uint64_t eventId, std::string&& msg)
{
    persistent_data::EventServiceConfig eventServiceConfig =
        persistent_data::EventServiceStore::getInstance()
            .getEventServiceConfig();
    if (!eventServiceConfig.enabled)
    {
        return false;
    }

    if (client)
    {
        boost::beast::http::fields httpHeadersCopy(userSub->httpHeaders);
        httpHeadersCopy.set(boost::beast::http::field::content_type,
                            "application/json");
        client->sendDataWithCallback(
            std::move(msg), userSub->destinationUrl,
            static_cast<ensuressl::VerifyCertificate>(
                userSub->verifyCertificate),
            httpHeadersCopy, boost::beast::http::verb::post,
            std::bind_front(&Subscription::resHandler, this,
                            shared_from_this()));
        return true;
    }

    if (sseConn != nullptr)
    {
        sseConn->sendSseEvent(std::to_string(eventId), msg);
    }
    return true;
}

void Subscription::filterAndSendEventLogs(
    uint64_t eventId, const std::vector<EventLogObjectsType>& eventRecords)
{
    nlohmann::json::array_t logEntryArray;
    for (const EventLogObjectsType& logEntry : eventRecords)
    {
        BMCWEB_LOG_DEBUG("Processing logEntry: {}, {} '{}'", logEntry.id,
                         logEntry.timestamp, logEntry.messageId);
        std::vector<std::string_view> messageArgsView(
            logEntry.messageArgs.begin(), logEntry.messageArgs.end());

        nlohmann::json::object_t bmcLogEntry;
        if (event_log::formatEventLogEntry(
                eventId, logEntry.id, logEntry.messageId, messageArgsView,
                logEntry.timestamp, userSub->customText, bmcLogEntry) != 0)
        {
            BMCWEB_LOG_WARNING("Read eventLog entry failed");
            continue;
        }

        if (!eventMatchesFilter(*userSub, bmcLogEntry, ""))
        {
            BMCWEB_LOG_DEBUG("Event {} did not match the filter",
                             nlohmann::json(bmcLogEntry).dump());
            continue;
        }

        if (filter)
        {
            if (!memberMatches(bmcLogEntry, *filter))
            {
                BMCWEB_LOG_DEBUG("Filter didn't match");
                continue;
            }
        }

        logEntryArray.emplace_back(std::move(bmcLogEntry));
        eventId++;
    }

    if (logEntryArray.empty())
    {
        BMCWEB_LOG_DEBUG("No log entries available to be transferred.");
        return;
    }

    nlohmann::json msg;
    msg["@odata.type"] = "#Event.v1_4_0.Event";
    msg["Id"] = std::to_string(eventId);
    msg["Name"] = "Event Log";
    msg["Events"] = std::move(logEntryArray);
    std::string strMsg =
        msg.dump(2, ' ', true, nlohmann::json::error_handler_t::replace);
    sendEventToSubscriber(eventId, std::move(strMsg));
}

void Subscription::filterAndSendReports(uint64_t eventId,
                                        const std::string& reportId,
                                        const telemetry::TimestampReadings& var)
{
    boost::urls::url mrdUri = boost::urls::format(
        "/redfish/v1/TelemetryService/MetricReportDefinitions/{}", reportId);

    // Empty list means no filter. Send everything.
    if (!userSub->metricReportDefinitions.empty())
    {
        if (std::ranges::find(userSub->metricReportDefinitions,
                              mrdUri.buffer()) ==
            userSub->metricReportDefinitions.end())
        {
            return;
        }
    }

    nlohmann::json msg;
    if (!telemetry::fillReport(msg, reportId, var))
    {
        BMCWEB_LOG_ERROR("Failed to fill the MetricReport for DBus "
                         "Report with id {}",
                         reportId);
        return;
    }

    // Context is set by user during Event subscription and it must be
    // set for MetricReport response.
    if (!userSub->customText.empty())
    {
        msg["Context"] = userSub->customText;
    }

    std::string strMsg =
        msg.dump(2, ' ', true, nlohmann::json::error_handler_t::replace);
    sendEventToSubscriber(eventId, std::move(strMsg));
}

void Subscription::updateRetryConfig(uint32_t retryAttempts,
                                     uint32_t retryTimeoutInterval)
{
    if (policy == nullptr)
    {
        BMCWEB_LOG_DEBUG("Retry policy was nullptr, ignoring set");
        return;
    }
    policy->maxRetryAttempts = retryAttempts;
    policy->retryIntervalSecs = std::chrono::seconds(retryTimeoutInterval);
}

bool Subscription::matchSseId(const crow::sse_socket::Connection& thisConn)
{
    return &thisConn == sseConn;
}

// Check used to indicate what response codes are valid as part of our retry
// policy.  2XX is considered acceptable
boost::system::error_code Subscription::retryRespHandler(unsigned int respCode)
{
    BMCWEB_LOG_DEBUG("Checking response code validity for SubscriptionEvent");
    if ((respCode < 200) || (respCode >= 300))
    {
        return boost::system::errc::make_error_code(
            boost::system::errc::result_out_of_range);
    }

    // Return 0 if the response code is valid
    return boost::system::errc::make_error_code(boost::system::errc::success);
}

} // namespace redfish