/*
 * Squawk messenger.
 * Copyright (C) 2019  Yury Gubich <blue@macaw.me>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "manager.h"

#include <QDebug>

#include "cardinternal.h"
#include "infoforuser.h"
#include "owncardinternal.h"
#include "owninfoforuser.h"

Core::DelayManager::Manager::Manager(const QString& poj, Job::Id mpj, QObject* parent) :
    QObject(parent),
    maxParallelJobs(mpj),
    nextJobId(1),
    scheduledJobs(),
    scheduledJobsById(scheduledJobs.get<id>()),
    jobSequence(scheduledJobs.get<sequence>()),
    runningJobs(),
    ownVCardJobId(0),
    ownInfoJobId(0),
    scheduledVCards(),
    requestedVCards(),
#ifdef WITH_OMEMO
    requestedBundles(),
#endif
    ownJid(poj)
{}

Core::DelayManager::Manager::~Manager() {
    for (const std::pair<const Job::Id, Job*>& pair : runningJobs)
        delete pair.second;

    for (Job* job : jobSequence)
        delete job;
}

Core::DelayManager::Job::Id Core::DelayManager::Manager::getNextJobId() {
    Job::Id id = nextJobId++;
    if (id == 0)
        id = nextJobId++;

    return id;
}

void Core::DelayManager::Manager::getInfo(const QString& jid) {
    if (jid == ownJid)
        return getOwnInfo();

    Job* job = nullptr;
#ifdef WITH_OMEMO
    std::map<QString, Job::Id>::const_iterator bitr = requestedBundles.find(jid);
    if (bitr != requestedBundles.end()) {
        std::map<Job::Id, Job*>::const_iterator itr = runningJobs.find(bitr->second);
        if (itr == runningJobs.end())
            throw JobNotFound(bitr->second);

        job = itr->second;
    }
    else
#endif
        job = getVCardJob(jid);

    if (job != nullptr) {
        if (job->type == Job::Type::cardInternal)
            replaceJob(new InfoForUser(job->id, jid));
    } else
        scheduleJob(new InfoForUser(getNextJobId(), jid));
}

void Core::DelayManager::Manager::getOwnInfo() {
    if (ownInfoJobId == 0) {
        if (ownVCardJobId != 0)
            replaceJob(new OwnInfoForUser(ownVCardJobId));
        else
            scheduleJob(new OwnInfoForUser(getNextJobId()));
    }
}

void Core::DelayManager::Manager::getVCard(const QString& jid) {
    Job* job = getVCardJob(jid);
    if (job == nullptr)
        scheduleJob(new CardInternal(getNextJobId(), jid));
}

void Core::DelayManager::Manager::getOwnVCard() {
    if (ownVCardJobId == 0)
        scheduleJob(new OwnCardInternal(getNextJobId()));
}

bool Core::DelayManager::Manager::isOwnVCardPending() const {
    return ownVCardJobId != 0;
}

Core::DelayManager::Job* Core::DelayManager::Manager::getVCardJob(const QString& jid) {
    Job* job = nullptr;
    std::map<QString, Job::Id>::const_iterator sitr = scheduledVCards.find(jid);
    if (sitr == scheduledVCards.end()) {
        std::map<QString, Job::Id>::const_iterator ritr = requestedVCards.find(jid);
        if (ritr != requestedVCards.end()) {
            std::map<Job::Id, Job*>::const_iterator itr = runningJobs.find(ritr->second);
            if (itr == runningJobs.end())
                throw JobNotFound(ritr->second, "getVCardJob:1");

            job = itr->second;
        }
    } else {
        StorageById::const_iterator itr = scheduledJobsById.find(sitr->second);
        if (itr == scheduledJobsById.end())
            throw JobNotFound(sitr->second, "getVCardJob:2");

        job = *itr;
    }

    return job;
}
void Core::DelayManager::Manager::preScheduleJob(Job* job) {
    switch (job->type) {
        case Job::Type::cardInternal:
            scheduledVCards.emplace(dynamic_cast<CardInternal*>(job)->jid, job->id);
            break;
        case Job::Type::ownCardInternal:
            ownVCardJobId = job->id;
            break;
        case Job::Type::infoForUser:
            scheduledVCards.emplace(dynamic_cast<InfoForUser*>(job)->jid, job->id);
            break;
        case Job::Type::ownInfoForUser:
            ownVCardJobId = job->id;
            ownInfoJobId = job->id;
            break;
    }
}

void Core::DelayManager::Manager::scheduleJob(Job* job) {
    preScheduleJob(job);
    if (runningJobs.size() < maxParallelJobs)
        executeJob(job);
    else
        scheduledJobs.push_back(job);
}

void Core::DelayManager::Manager::preExecuteJob(Job* job) {
    switch (job->type) {
        case Job::Type::cardInternal:
        case Job::Type::infoForUser: {
            Contact* cij = dynamic_cast<Contact*>(job);
            requestedVCards.emplace(cij->jid, job->id);
            scheduledVCards.erase(cij->jid);
        }
            break;
        case Job::Type::ownInfoForUser:
        case Job::Type::ownCardInternal:
            break;
    }
}

void Core::DelayManager::Manager::executeJob(Job* job) {
    preExecuteJob(job);
    runningJobs.emplace(job->id, job);
    switch (job->type) {
        case Job::Type::cardInternal:
        case Job::Type::infoForUser:
            emit requestVCard(dynamic_cast<Contact*>(job)->jid);
            break;
        case Job::Type::ownInfoForUser:
        case Job::Type::ownCardInternal:
            emit requestOwnVCard();
            break;
    }
}

void Core::DelayManager::Manager::jobIsDone(Job::Id jobId) {
    std::map<Job::Id, Job*>::const_iterator itr = runningJobs.find(jobId);
    if (itr == runningJobs.end())
        throw JobNotFound(jobId, "jobIsDone");

    Job* job = itr->second;
    delete job;
    runningJobs.erase(itr);
    if (scheduledJobs.size() > 0) {
        Job* job = scheduledJobs.front();
        scheduledJobs.pop_front();
        executeJob(job);
    }
}

void Core::DelayManager::Manager::replaceJob(Job* job) {
    preScheduleJob(job);
    std::map<Job::Id, Job*>::iterator itr = runningJobs.find(job->id);
    if (itr != runningJobs.end()) {
        preExecuteJob(job);
        delete itr->second;
        itr->second = job;
    } else {
        StorageById::iterator sitr = scheduledJobsById.find(job->id);
        if (sitr != scheduledJobsById.end()) {
            delete *(sitr);
            scheduledJobsById.replace(sitr, job);
        } else
            throw JobNotFound(job->id, "replaceJob");
    }
}

void Core::DelayManager::Manager::jobIsCanceled(Job* job, bool wasRunning) {
    switch (job->type) {
        case Job::Type::cardInternal: {
            CardInternal* jb = dynamic_cast<CardInternal*>(job);
            if (wasRunning)
                requestedVCards.erase(jb->jid);
            else
                scheduledVCards.erase(jb->jid);

            emit gotVCard(jb->jid, Shared::VCard());
        }
            break;
        case Job::Type::infoForUser: {
            InfoForUser* jb = dynamic_cast<InfoForUser*>(job);
            switch (jb->getStage()) {
                case InfoForUser::Stage::waitingForVCard:
                    if (wasRunning)
                        requestedVCards.erase(jb->jid);
                    else
                        scheduledVCards.erase(jb->jid);

                    emit gotVCard(jb->jid, Shared::VCard());
                    break;
                case InfoForUser::Stage::waitingForBundles:
#ifdef WITH_OMEMO
                    requestedBundles.erase(jb->jid);
#endif
                    break;
                default:
                    break;
            }
            emit gotInfo(Shared::Info(jb->jid));
        }
            break;
        case Job::Type::ownInfoForUser: {
            OwnInfoForUser* jb = dynamic_cast<OwnInfoForUser*>(job);
            if (jb->getStage() == OwnInfoForUser::Stage::waitingForVCard) {
                ownVCardJobId = 0;
                emit gotOwnVCard(Shared::VCard());
            }
            ownInfoJobId = 0;
            emit gotOwnInfo(Shared::Info (ownJid));
        }

            break;
        case Job::Type::ownCardInternal:
            ownVCardJobId = 0;
            emit gotOwnVCard(Shared::VCard());
            break;
    }

    delete job;
}

void Core::DelayManager::Manager::disconnected() {
    for (const std::pair<const Job::Id, Job*> pair : runningJobs)
        jobIsCanceled(pair.second, true);

    for (Job* job : scheduledJobs)
        jobIsCanceled(job, false);

    runningJobs.clear();
    scheduledJobs.clear();
}

void Core::DelayManager::Manager::receivedVCard(const QString& jid, const Shared::VCard& card) {
    std::map<QString, Job::Id>::const_iterator cardItr = requestedVCards.find(jid);
    if (cardItr == requestedVCards.end()) {
        qDebug() << "received VCard for" << jid << "but it was never requested through manager, ignoring";
        return;
    }
    Job::Id jobId = cardItr->second;
    requestedVCards.erase(cardItr);
    std::map<Job::Id, Job*>::const_iterator itr = runningJobs.find(jobId);
    if (itr == runningJobs.end())
        throw JobNotFound(jobId, "receivedVCard");

    Job* job = itr->second;

    switch (job->type) {
        case Job::Type::cardInternal:
            jobIsDone(jobId);
            emit gotVCard(jid, card);
            break;
        case Job::Type::infoForUser: {
#ifdef WITH_OMEMO
            requestedBundles.emplace(jid, jobId);
            InfoForUser* jb = dynamic_cast<InfoForUser*>(job);
            jb->receivedVCard(card);
            emit requestBundles(jid);
#else
            Shared::Info info(jid);
            info.turnIntoContact(card);
            emit gotInfo(info);
            jobIsDone(jobId);
#endif
            emit gotVCard(jid, card);
        }
            break;
        default:
            throw UnexpectedJobType(job->type, "receivedVCard");
    }
}

void Core::DelayManager::Manager::receivedOwnVCard(const Shared::VCard& card) {
    if (ownVCardJobId == 0) {
        qDebug() << "received own VCard for" << ownJid << "but it was never requested through manager, ignoring";
        return;
    }
    Job::Id jobId = ownVCardJobId;
    ownVCardJobId = 0;
    std::map<Job::Id, Job*>::const_iterator itr = runningJobs.find(jobId);
    if (itr == runningJobs.end())
        throw JobNotFound(jobId, "receivedOwnVCard");

    Job* job = itr->second;
    switch (job->type) {
        case Job::Type::ownCardInternal:
            jobIsDone(jobId);
            emit gotOwnVCard(card);
            break;
        case Job::Type::ownInfoForUser: {
#ifdef WITH_OMEMO
            OwnInfoForUser* jb = dynamic_cast<OwnInfoForUser*>(job);
            jb->receivedVCard(card);
            emit requestOwnBundles();
#else
            Shared::Info info(ownJid);
            info.turnIntoOwnAccount(card);
            emit gotOwnInfo(info);
            jobIsDone(jobId);
#endif
            emit gotOwnVCard(card);
        }
            break;
        default:
            throw UnexpectedJobType(job->type, "receivedVCard");
    }
}

#ifdef WITH_OMEMO
void Core::DelayManager::Manager::receivedBundles(const QString& jid, const std::list<Shared::KeyInfo>& keys) {
    std::map<QString, Job::Id>::const_iterator itr = requestedBundles.find(jid);
    if (itr == requestedBundles.end()) {
        qDebug() << "received bundles for" << jid << "but they were never requested through manager, ignoring";
        return;
    }

    Job::Id jobId = itr->second;
    requestedBundles.erase(itr);
    std::map<Job::Id, Job*>::const_iterator jitr = runningJobs.find(jobId);
    if (jitr == runningJobs.end())
        throw JobNotFound(jobId, "receivedBundles");

    Job* jb = jitr->second;
    InfoForUser* job = dynamic_cast<InfoForUser*>(jb);

    Shared::Info info(jid);
    info.turnIntoContact(job->claim(), new std::list<Shared::KeyInfo>(keys));
    emit gotInfo(info);
    jobIsDone(jobId);
}

void Core::DelayManager::Manager::receivedOwnBundles(const std::list<Shared::KeyInfo>& keys) {
    if (ownInfoJobId == 0) {
        qDebug() << "received own bundles for" << ownJid << "but they were never requested through manager, ignoring";
        return;
    }
    Job::Id jobId = ownInfoJobId;
    ownInfoJobId = 0;
    std::map<Job::Id, Job*>::const_iterator jitr = runningJobs.find(jobId);
    if (jitr == runningJobs.end())
        throw JobNotFound(jobId, "receivedOwnBundles");

    Job* jb = jitr->second;
    OwnInfoForUser* job = dynamic_cast<OwnInfoForUser*>(jb);

    Shared::Info info(ownJid);
    info.turnIntoOwnAccount(job->claim(), new std::list<Shared::KeyInfo>(keys));
    emit gotOwnInfo(info);
    jobIsDone(jobId);
}
#endif

void Core::DelayManager::Manager::setOwnJid(const QString& jid) {
    ownJid = jid;
}


Core::DelayManager::Manager::UnexpectedJobType::UnexpectedJobType(Job::Type p_type, const std::string& p_method):
    Exception(),
    type(p_type),
    method(p_method)
{}

std::string Core::DelayManager::Manager::UnexpectedJobType::getMessage() const{
    std::string msg("Unexpected job type: ");
    msg += Job::TypeString[static_cast<int>(type)];
    if (method.size() > 0)
        msg += " in method " + method;

    return msg;
}

Core::DelayManager::Manager::JobNotFound::JobNotFound(Job::Id p_id, const std::string& p_method) :
    Exception(),
    id(p_id),
    method(p_method)
{}

std::string Core::DelayManager::Manager::JobNotFound::getMessage() const {
    std::string msg("Job with id ");
    msg += std::to_string(id);
    msg += " was not found";
    if (method.size() > 0)
        msg += " in method " + method;

    return msg;
}