/*
Copyright (c) 2020 Intel Corporation

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#pragma once

#include "app.hpp"
#include "dbus_utility.hpp"
#include "event_service_manager.hpp"
#include "generated/enums/resource.hpp"
#include "generated/enums/task_service.hpp"
#include "http/parsing.hpp"
#include "query.hpp"
#include "registries/privilege_registry.hpp"
#include "task_messages.hpp"

#include <boost/asio/post.hpp>
#include <boost/asio/steady_timer.hpp>
#include <boost/url/format.hpp>
#include <sdbusplus/bus/match.hpp>

#include <chrono>
#include <memory>
#include <ranges>
#include <variant>

namespace redfish
{

namespace task
{
constexpr size_t maxTaskCount = 100; // arbitrary limit

// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
static std::deque<std::shared_ptr<struct TaskData>> tasks;

constexpr bool completed = true;

struct Payload
{
    explicit Payload(const crow::Request& req) :
        targetUri(req.url().encoded_path()), httpOperation(req.methodString()),
        httpHeaders(nlohmann::json::array())
    {
        using field_ns = boost::beast::http::field;
        constexpr const std::array<boost::beast::http::field, 7>
            headerWhitelist = {field_ns::accept,     field_ns::accept_encoding,
                               field_ns::user_agent, field_ns::host,
                               field_ns::connection, field_ns::content_length,
                               field_ns::upgrade};

        JsonParseResult ret = parseRequestAsJson(req, jsonBody);
        if (ret != JsonParseResult::Success)
        {
            return;
        }

        for (const auto& field : req.fields())
        {
            if (std::ranges::find(headerWhitelist, field.name()) ==
                headerWhitelist.end())
            {
                continue;
            }
            std::string header;
            header.reserve(
                field.name_string().size() + 2 + field.value().size());
            header += field.name_string();
            header += ": ";
            header += field.value();
            httpHeaders.emplace_back(std::move(header));
        }
    }
    Payload() = delete;

    std::string targetUri;
    std::string httpOperation;
    nlohmann::json httpHeaders;
    nlohmann::json jsonBody;
};

struct TaskData : std::enable_shared_from_this<TaskData>
{
  private:
    TaskData(
        std::function<bool(boost::system::error_code, sdbusplus::message_t&,
                           const std::shared_ptr<TaskData>&)>&& handler,
        const std::string& matchIn, size_t idx) :
        callback(std::move(handler)), matchStr(matchIn), index(idx),
        startTime(std::chrono::system_clock::to_time_t(
            std::chrono::system_clock::now())),
        status("OK"), state("Running"), messages(nlohmann::json::array()),
        timer(crow::connections::systemBus->get_io_context())

    {}

  public:
    TaskData() = delete;

    static std::shared_ptr<TaskData>& createTask(
        std::function<bool(boost::system::error_code, sdbusplus::message_t&,
                           const std::shared_ptr<TaskData>&)>&& handler,
        const std::string& match)
    {
        static size_t lastTask = 0;
        struct MakeSharedHelper : public TaskData
        {
            MakeSharedHelper(
                std::function<bool(boost::system::error_code,
                                   sdbusplus::message_t&,
                                   const std::shared_ptr<TaskData>&)>&& handler,
                const std::string& match2, size_t idx) :
                TaskData(std::move(handler), match2, idx)
            {}
        };

        if (tasks.size() >= maxTaskCount)
        {
            const auto& last = tasks.front();

            // destroy all references
            last->timer.cancel();
            last->match.reset();
            tasks.pop_front();
        }

        return tasks.emplace_back(std::make_shared<MakeSharedHelper>(
            std::move(handler), match, lastTask++));
    }

    void populateResp(crow::Response& res, size_t retryAfterSeconds = 30)
    {
        if (!endTime)
        {
            res.result(boost::beast::http::status::accepted);
            std::string strIdx = std::to_string(index);
            boost::urls::url uri =
                boost::urls::format("/redfish/v1/TaskService/Tasks/{}", strIdx);

            res.jsonValue["@odata.id"] = uri;
            res.jsonValue["@odata.type"] = "#Task.v1_4_3.Task";
            res.jsonValue["Id"] = strIdx;
            res.jsonValue["TaskState"] = state;
            res.jsonValue["TaskStatus"] = status;

            boost::urls::url taskMonitor = boost::urls::format(
                "/redfish/v1/TaskService/TaskMonitors/{}", strIdx);

            res.addHeader(boost::beast::http::field::location,
                          taskMonitor.buffer());
            res.addHeader(boost::beast::http::field::retry_after,
                          std::to_string(retryAfterSeconds));
        }
        else if (!gave204)
        {
            res.result(boost::beast::http::status::no_content);
            gave204 = true;
        }
    }

    void finishTask()
    {
        endTime = std::chrono::system_clock::to_time_t(
            std::chrono::system_clock::now());
    }

    void extendTimer(const std::chrono::seconds& timeout)
    {
        timer.expires_after(timeout);
        timer.async_wait(
            [self = shared_from_this()](boost::system::error_code ec) {
                if (ec == boost::asio::error::operation_aborted)
                {
                    return; // completed successfully
                }
                if (!ec)
                {
                    // change ec to error as timer expired
                    ec = boost::asio::error::operation_aborted;
                }
                self->match.reset();
                sdbusplus::message_t msg;
                self->finishTask();
                self->state = "Cancelled";
                self->status = "Warning";
                self->messages.emplace_back(
                    messages::taskAborted(std::to_string(self->index)));
                // Send event :TaskAborted
                self->sendTaskEvent(self->state, self->index);
                self->callback(ec, msg, self);
            });
    }

    static void sendTaskEvent(std::string_view state, size_t index)
    {
        // TaskState enums which should send out an event are:
        // "Starting" = taskResumed
        // "Running" = taskStarted
        // "Suspended" = taskPaused
        // "Interrupted" = taskPaused
        // "Pending" = taskPaused
        // "Stopping" = taskAborted
        // "Completed" = taskCompletedOK
        // "Killed" = taskRemoved
        // "Exception" = taskCompletedWarning
        // "Cancelled" = taskCancelled
        nlohmann::json event;
        std::string indexStr = std::to_string(index);
        if (state == "Starting")
        {
            event = redfish::messages::taskResumed(indexStr);
        }
        else if (state == "Running")
        {
            event = redfish::messages::taskStarted(indexStr);
        }
        else if ((state == "Suspended") || (state == "Interrupted") ||
                 (state == "Pending"))
        {
            event = redfish::messages::taskPaused(indexStr);
        }
        else if (state == "Stopping")
        {
            event = redfish::messages::taskAborted(indexStr);
        }
        else if (state == "Completed")
        {
            event = redfish::messages::taskCompletedOK(indexStr);
        }
        else if (state == "Killed")
        {
            event = redfish::messages::taskRemoved(indexStr);
        }
        else if (state == "Exception")
        {
            event = redfish::messages::taskCompletedWarning(indexStr);
        }
        else if (state == "Cancelled")
        {
            event = redfish::messages::taskCancelled(indexStr);
        }
        else
        {
            BMCWEB_LOG_INFO("sendTaskEvent: No events to send");
            return;
        }
        boost::urls::url origin =
            boost::urls::format("/redfish/v1/TaskService/Tasks/{}", index);
        EventServiceManager::getInstance().sendEvent(event, origin.buffer(),
                                                     "Task");
    }

    void startTimer(const std::chrono::seconds& timeout)
    {
        if (match)
        {
            return;
        }
        match = std::make_unique<sdbusplus::bus::match_t>(
            static_cast<sdbusplus::bus_t&>(*crow::connections::systemBus),
            matchStr,
            [self = shared_from_this()](sdbusplus::message_t& message) {
                boost::system::error_code ec;

                // callback to return True if callback is done, callback needs
                // to update status itself if needed
                if (self->callback(ec, message, self) == task::completed)
                {
                    self->timer.cancel();
                    self->finishTask();

                    // Send event
                    self->sendTaskEvent(self->state, self->index);

                    // reset the match after the callback was successful
                    boost::asio::post(
                        crow::connections::systemBus->get_io_context(),
                        [self] { self->match.reset(); });
                    return;
                }
            });

        extendTimer(timeout);
        messages.emplace_back(messages::taskStarted(std::to_string(index)));
        // Send event : TaskStarted
        sendTaskEvent(state, index);
    }

    std::function<bool(boost::system::error_code, sdbusplus::message_t&,
                       const std::shared_ptr<TaskData>&)>
        callback;
    std::string matchStr;
    size_t index;
    time_t startTime;
    std::string status;
    std::string state;
    nlohmann::json messages;
    boost::asio::steady_timer timer;
    std::unique_ptr<sdbusplus::bus::match_t> match;
    std::optional<time_t> endTime;
    std::optional<Payload> payload;
    bool gave204 = false;
    int percentComplete = 0;
};

} // namespace task

inline void requestRoutesTaskMonitor(App& app)
{
    BMCWEB_ROUTE(app, "/redfish/v1/TaskService/TaskMonitors/<str>/")
        .privileges(redfish::privileges::getTask)
        .methods(boost::beast::http::verb::get)(
            [&app](const crow::Request& req,
                   const std::shared_ptr<bmcweb::AsyncResp>& asyncResp,
                   const std::string& strParam) {
                if (!redfish::setUpRedfishRoute(app, req, asyncResp))
                {
                    return;
                }
                auto find = std::ranges::find_if(
                    task::tasks,
                    [&strParam](const std::shared_ptr<task::TaskData>& task) {
                        if (!task)
                        {
                            return false;
                        }

                        // we compare against the string version as on failure
                        // strtoul returns 0
                        return std::to_string(task->index) == strParam;
                    });

                if (find == task::tasks.end())
                {
                    messages::resourceNotFound(asyncResp->res, "Task",
                                               strParam);
                    return;
                }
                std::shared_ptr<task::TaskData>& ptr = *find;
                // monitor expires after 204
                if (ptr->gave204)
                {
                    messages::resourceNotFound(asyncResp->res, "Task",
                                               strParam);
                    return;
                }
                ptr->populateResp(asyncResp->res);
            });
}

inline void requestRoutesTask(App& app)
{
    BMCWEB_ROUTE(app, "/redfish/v1/TaskService/Tasks/<str>/")
        .privileges(redfish::privileges::getTask)
        .methods(boost::beast::http::verb::get)(
            [&app](const crow::Request& req,
                   const std::shared_ptr<bmcweb::AsyncResp>& asyncResp,
                   const std::string& strParam) {
                if (!redfish::setUpRedfishRoute(app, req, asyncResp))
                {
                    return;
                }
                auto find = std::ranges::find_if(
                    task::tasks,
                    [&strParam](const std::shared_ptr<task::TaskData>& task) {
                        if (!task)
                        {
                            return false;
                        }

                        // we compare against the string version as on failure
                        // strtoul returns 0
                        return std::to_string(task->index) == strParam;
                    });

                if (find == task::tasks.end())
                {
                    messages::resourceNotFound(asyncResp->res, "Task",
                                               strParam);
                    return;
                }

                const std::shared_ptr<task::TaskData>& ptr = *find;

                asyncResp->res.jsonValue["@odata.type"] = "#Task.v1_4_3.Task";
                asyncResp->res.jsonValue["Id"] = strParam;
                asyncResp->res.jsonValue["Name"] = "Task " + strParam;
                asyncResp->res.jsonValue["TaskState"] = ptr->state;
                asyncResp->res.jsonValue["StartTime"] =
                    redfish::time_utils::getDateTimeStdtime(ptr->startTime);
                if (ptr->endTime)
                {
                    asyncResp->res.jsonValue["EndTime"] =
                        redfish::time_utils::getDateTimeStdtime(
                            *(ptr->endTime));
                }
                asyncResp->res.jsonValue["TaskStatus"] = ptr->status;
                asyncResp->res.jsonValue["Messages"] = ptr->messages;
                asyncResp->res.jsonValue["@odata.id"] = boost::urls::format(
                    "/redfish/v1/TaskService/Tasks/{}", strParam);
                if (!ptr->gave204)
                {
                    asyncResp->res.jsonValue["TaskMonitor"] =
                        boost::urls::format(
                            "/redfish/v1/TaskService/TaskMonitors/{}",
                            strParam);
                }

                asyncResp->res.jsonValue["HidePayload"] = !ptr->payload;

                if (ptr->payload)
                {
                    const task::Payload& p = *(ptr->payload);
                    asyncResp->res.jsonValue["Payload"]["TargetUri"] =
                        p.targetUri;
                    asyncResp->res.jsonValue["Payload"]["HttpOperation"] =
                        p.httpOperation;
                    asyncResp->res.jsonValue["Payload"]["HttpHeaders"] =
                        p.httpHeaders;
                    asyncResp->res.jsonValue["Payload"]["JsonBody"] =
                        p.jsonBody.dump(
                            -1, ' ', true,
                            nlohmann::json::error_handler_t::replace);
                }
                asyncResp->res.jsonValue["PercentComplete"] =
                    ptr->percentComplete;
            });
}

inline void requestRoutesTaskCollection(App& app)
{
    BMCWEB_ROUTE(app, "/redfish/v1/TaskService/Tasks/")
        .privileges(redfish::privileges::getTaskCollection)
        .methods(boost::beast::http::verb::get)(
            [&app](const crow::Request& req,
                   const std::shared_ptr<bmcweb::AsyncResp>& asyncResp) {
                if (!redfish::setUpRedfishRoute(app, req, asyncResp))
                {
                    return;
                }
                asyncResp->res.jsonValue["@odata.type"] =
                    "#TaskCollection.TaskCollection";
                asyncResp->res.jsonValue["@odata.id"] =
                    "/redfish/v1/TaskService/Tasks";
                asyncResp->res.jsonValue["Name"] = "Task Collection";
                asyncResp->res.jsonValue["Members@odata.count"] =
                    task::tasks.size();
                nlohmann::json& members = asyncResp->res.jsonValue["Members"];
                members = nlohmann::json::array();

                for (const std::shared_ptr<task::TaskData>& task : task::tasks)
                {
                    if (task == nullptr)
                    {
                        continue; // shouldn't be possible
                    }
                    nlohmann::json::object_t member;
                    member["@odata.id"] =
                        boost::urls::format("/redfish/v1/TaskService/Tasks/{}",
                                            std::to_string(task->index));
                    members.emplace_back(std::move(member));
                }
            });
}

inline void requestRoutesTaskService(App& app)
{
    BMCWEB_ROUTE(app, "/redfish/v1/TaskService/")
        .privileges(redfish::privileges::getTaskService)
        .methods(boost::beast::http::verb::get)(
            [&app](const crow::Request& req,
                   const std::shared_ptr<bmcweb::AsyncResp>& asyncResp) {
                if (!redfish::setUpRedfishRoute(app, req, asyncResp))
                {
                    return;
                }
                asyncResp->res.jsonValue["@odata.type"] =
                    "#TaskService.v1_1_4.TaskService";
                asyncResp->res.jsonValue["@odata.id"] =
                    "/redfish/v1/TaskService";
                asyncResp->res.jsonValue["Name"] = "Task Service";
                asyncResp->res.jsonValue["Id"] = "TaskService";
                asyncResp->res.jsonValue["DateTime"] =
                    redfish::time_utils::getDateTimeOffsetNow().first;
                asyncResp->res.jsonValue["CompletedTaskOverWritePolicy"] =
                    task_service::OverWritePolicy::Oldest;

                asyncResp->res.jsonValue["LifeCycleEventOnTaskStateChange"] =
                    true;

                asyncResp->res.jsonValue["Status"]["State"] =
                    resource::State::Enabled;
                asyncResp->res.jsonValue["ServiceEnabled"] = true;
                asyncResp->res.jsonValue["Tasks"]["@odata.id"] =
                    "/redfish/v1/TaskService/Tasks";
            });
}

} // namespace redfish