/* Copyright (C) 2023 The Qt Company Ltd.
 *
 * SPDX-License-Identifier: GPL-3.0-only WITH Qt-GPL-exception-1.0
*/

#include "licenser.h"

#include "commonsetup.h"

#include "clienthandlerfactory.h"
#include "clitoolhandler.h"
#include "version.h"
#include "utils.h"
#include "errors.h"

namespace QLicenseService {

Licenser::Licenser(uint16_t tcpPort, const std::string &settingsPath)
{
    // Init daemon settings
    m_settings = new LicdSetup(e_set_type_daemon,
                               settingsPath.empty() ? DAEMON_SETTINGS_FILE : settingsPath);
    m_settings->initSettings();

    if (m_settings->get("license_key").empty()) {
        std::cout << "Warning: No license key provided in qtlicd.ini, required for cloud operation\n";
    }

    if (tcpPort == 0) {
        tcpPort = utils::strToInt(m_settings->get("tcp_listening_port"));
    }
    m_mocInterval = utils::strToInt(m_settings->get("moc_renewal_interval")) * SECS_IN_HOUR;
    // Start the HTTP client
    m_http = new HttpClient(m_settings->get("server_addr"));
    // Start the TCP/IP server
    m_tcpServer = new TcpServer(tcpPort);
    if (!m_tcpServer->init()) {
        throw Error("Error while initializing TCP server in port: "
            + std::to_string(tcpPort));
    }
}

Licenser::~Licenser()
{
    delete(m_settings);
    delete(m_tcpServer);
    delete(m_http);
    std::cout << "Daemon stopped." << std::endl;
}

int Licenser::listen()
{
    m_infoString = "";
    uint16_t socketId = 0; // Placeholder for whatever socket gets active
    std::string input;
    if (!m_tcpServer->listenToClients(socketId, &input))
        throw QLicenseService::Error("Error while listening to clients!");

    input = utils::trimStr(input);

    if (input.empty()) {
        if (m_floatingClients.size() > 0) {
            checkTasksDue();
        }
        return 0; //continue;
    }
    if (input == SOCKET_CLOSED_MSG) {
        std::cout << "Client disconnected, socket id " << socketId << std::endl;
        removeReservation(socketId);
        return 0;
    }

    std::cout << "Got a request: " << input << std::endl;
    //  Check if we already have this client in storage (floating one):
    if (clientInStorage(socketId)) {
        // do nothing - floating clients should only send request at startup
        std::cout << "Floating client with ID " << socketId << " sent something while working: ignoring\n";
        m_tcpServer->sendResponse(socketId, "NOK\n");
        return 0;
    }
    std::string reply = ""; // Holds server response first (if got any). After parsing, holds reply to the client
    bool removeRes = false;

    std::unique_ptr<ClientHandler> currentClient(parseInputAndCreateCLient(socketId, input));
    if (currentClient) {
        if (currentClient->parseRequest() != e_bad_request) {
            RequestType reqType = currentClient->getRequestType();
            if (reqType == RequestType::reservation_query) {
                reply = checkReservations();
            } else if (reqType == RequestType::daemon_version) {
                reply = getDaemonVersion();
            } else {
                if (currentClient->isLicenseRequestDue()) {
                    std::cout << "Initiating a request to the server\n";
                    if (sendServerRequest(currentClient->getRequest(), reply) == e_bad_connection) {
                        // Bad server connection: Check the existing license file for expiry date
                        if (!currentClient->isCachedReservationValid(reply)) {
                            reply = replyString[e_bad_connection];
                            removeRes = true;
                        }
                    } else if (currentClient->parseAndSaveResponse(reply) != 0) {
                        removeRes = true;
                    }
                } else {
                    // No need to contact server
                    reply = replyString[e_license_granted];
                }
            }
        } else {
            reply = replyString[e_bad_request];
            removeRes = true;
        }
    } else {
        reply = replyString[e_bad_request];
        removeRes = true;
    }
    if (currentClient->hasFloatingLicense()
                && !clientInStorage(socketId)
                && !removeRes) {
        // Store QA tool, Coco or Squish client (floating license) if not already stored
        if (currentClient->hasParent()) {
            if (!addClientToParent(currentClient.release())) {
                reply = replyString[e_license_rejected];
                m_infoString = " Parent reservation not found";
            }
        } else {
            std::cout << "Storing client in main cache\n";
            m_floatingClients[socketId] = currentClient.release();
        }
    }
    if (!m_infoString.empty()) {
        reply += ": ";
        reply += m_infoString;
    }
    reply +="\n";
    m_tcpServer->sendResponse(socketId, reply);
    std::cout << "Replied to socket " << socketId << ": " << reply << std::endl;

    if (removeRes) {
        // No license, remove reservation from cache (floating license)
        // or license file (site license)
        removeReservation(socketId);
        return 0;
    }

    if (m_floatingClients.size() > 0) {
        checkTasksDue();
    }
    return 0;
}


int Licenser::checkTasksDue() {
    // Check if there's any floating clients which has tasks to be done
    for (auto entry : m_floatingClients) {
        // First check if (parent) client has stopped and no children left
        if (entry.second->stopped() && !entry.second->hasChildren()) {
            removeReservation(entry.first);
            return 0;
        }
        // Then check if there is any server pings due
        if (entry.second->isLicenseRequestDue()) {
            std::string reply;
            if (sendServerRequest(entry.second->getRequest(), reply) != e_bad_connection) {
                std::cout << "Reported alive floating reservation with socket ID " << entry.first << std::endl;
                std::cout << "Client has " << entry.second->getNumberOfClients() << " sub-processes running\n";
                entry.second->resetTime();
            }
        }
    }
    return 0;
}


ClientHandler *Licenser::parseInputAndCreateCLient(uint16_t socketId, const std::string &incoming)
{
    // This parses client type from the input string and decides which type of client
    // to initiate into m_currentClient member

    RequestInfo request;
    request.socketId = socketId;

    // Find out which class of client is calling
    std::vector<std::string> paramList = utils::splitStr(incoming);
    std::string client;
    for ( int i = 0; i < paramList.size() ;i++ ) {
        std::string item = paramList.at(i);
        if (item == "-a" && paramList.size() > i) {
            client = paramList[i+1];
            break;
        }
    }

    if (client.empty()) {
        // Make this thing backwards compatible with old qtlicensetool
        // which does not send -a switch (app name)
        std::cout << "Warning: '-a' switch not found: Client undefined, assuming it's a CLI Tool" << std::endl;
        client = QTLICENSETOOL_APP_NAME;
    }

    ClientHandler *currentClient = ClientHandlerFactory::instance().create(client, request, *m_settings);
    if (!currentClient) {
        std::cout << "Warning: Client undefined!" << std::endl;
        return nullptr;
    }
    currentClient->params = paramList;
    return currentClient;
}

int Licenser::sendServerRequest(const RequestInfo &request, std::string &reply)
{
    std::string auth;

    // Generate auth hash for HTTP headers
    std::string hash;
    utils::doHmacHashSha256(request.payload, m_settings->get("server_secret"), hash);
    // For the HTTP 'Authorization' field
    auth = "apikey " + hash;

    // Send the request
    if (m_http->sendAndReceive(reply, request.payload,
                            request.accessPoint,
                            request.serverAddr, auth) != 0) {
        return e_bad_connection;
    }
    return e_got_response;
}

std::string Licenser::checkReservations()
{
    // Open all license files
    std::string dir = WORKING_DIR;
    std::string filter = LICENSE_FILE_PREFIX;
    std::vector<std::string> files = utils::getDirListing(dir, filter);

    std::stringstream reply;
    reply << "Current reservations: \n";
    for (auto file : files) {
        file = DIR_SEPARATOR + file;
        file = WORKING_DIR + file;
        std::cout << "File list: " << file << std::endl;
        std::string data;
        if (utils::readFile(data, file) != 0) {
            std::cout << "Couldn't read license file: " << file << std::endl;
            continue;
        }
        JsonHandler json(data);
        reply << "\n--- License ID " << json.get("license_number") << " ---\n";
        reply << " User ID: " << json.get("user_id") << std::endl;
        reply << " Expiry date: " << json.get("expiry_date") << std::endl;
        reply << " Reservation ID: " << json.get("reservation_id") << std::endl;
    }
    return reply.str();
}


bool Licenser::addClientToParent(ClientHandler *const client)
{
    bool found = false;
    for (auto parent : m_floatingClients) {
        if (parent.second->getReservationId() == client->getParentReservationId()) {
            parent.second->addChildClient(client);
            found = true;
            std::cout << "Stored client under reservation ID "
                << client->getParentReservationId() << std::endl;
            break;
        }
    }
    if (!found) {
        std::cout << "Warning! Not able to add current client under reservation ID "
                << client->getParentReservationId() << std::endl;
        return false;
    }
    return true;
}


void Licenser::removeReservation(int socketId) {
    // Close the socket
    m_tcpServer->closeClientSocket(socketId);
    // Check if the client had a floating license, or is a child of one.
    // Need to loop through all of them because socketId can be under any parent
    for (auto element : m_floatingClients) {
        ClientHandler* client = element.second;
        if (element.first == socketId) {
            if (!client->stopped()) {
                client->prepareRelease();
                // Don't remove parent yet, it might have child processes left
            }
            if (!client->hasChildren()) {
                // If client has no running children left, we can release the reservation and remove client
                std::string reply;
                client->release();
                client->buildRequestJson();
                if (sendServerRequest(client->getRequest(), reply) != e_bad_connection) {
                    // if connection succeeds, we can forget about this client
                    std::cout << "Removing floating reservation with ID " << client->getReservationId() << std::endl;
                    m_floatingClients.erase(socketId);
                    delete client;

                }
            }
            return;
        } else if (client->removeChildClient(socketId)) {
            std::cout << "Removed child client under reservation ID " << client->getReservationId() << std::endl;
            return;
        }
    }
    return;
}


bool Licenser::clientInStorage(uint16_t socketId) {
    for (auto client : m_floatingClients) {
        if (client.first == socketId) {
            return true;
        }
        if (client.second->hasChildren()) {
            if (client.second->clientInStorage(socketId)) {
                return true;
            }
        }
    }
    return false;
}


std::string Licenser::getDaemonVersion()
{
    std::string version = "Qt License Daemon (qtlicd) v";
    version += DAEMON_VERSION;
    return version;
}

} // namespace QLicenseService