#include "upgradelookup.h"
#include "manager.h"
#include "alpmdatabase.h"
#include "config.h"

#include <QtConcurrent/QtConcurrent>

#include <assert.h>

using namespace std;

namespace RepoIndex {

QJsonObject UpgradeResult::json() const
{
    QJsonObject obj;
    obj.insert(QStringLiteral("pkg"), package->basicInfo(true));
    obj.insert(QStringLiteral("prevVersion"), previousVersion);
    return obj;
}

UpgradeLookupProcess::UpgradeLookupProcess(UpgradeLookup *upgradeLookup, const Repository *upgradeSource) :
    QObject(upgradeLookup),
    m_toCheck(upgradeLookup->toCheck()),
    m_upgradeSource(upgradeSource),
    m_reply(nullptr),
    m_watcher(new QFutureWatcher<void>(this))
{
    connect(this, &UpgradeLookupProcess::finished, upgradeLookup, &UpgradeLookup::processFinished);
    switch(m_upgradeSource->requestsRequired()) {
    case PackageDetailAvailability::Request:
        m_reply = m_upgradeSource->requestPackageInfo(m_toCheck->packageNames());
        break;
    case PackageDetailAvailability::FullRequest:
        m_reply = m_upgradeSource->requestFullPackageInfo(m_toCheck->packageNames());
        break;
    case PackageDetailAvailability::Never:
        m_results.errors << QStringLiteral("Repository \"%1\" does not provide the required information.").arg(m_upgradeSource->name());
        emit finished();
        return;
    case PackageDetailAvailability::Immediately:
        break;
    }
    if(m_reply) {
        m_reply->setParent(this);
        connect(m_reply, &PackageReply::resultsAvailable, this, &UpgradeLookupProcess::sourceReady);
    } else {
        sourceReady();
    }
}

const UpgradeLookupResults &UpgradeLookupProcess::results() const
{
    return m_results;
}

void UpgradeLookupProcess::sourceReady()
{
    // if a request was required, check whether there occured an error
    if(m_reply && !m_reply->error().isEmpty()) {
        m_results.errors << m_reply->error();
        emit finished();
    } else {
        connect(m_watcher, &QFutureWatcher<void>::finished, this, &UpgradeLookupProcess::finished);
        m_watcher->setFuture(QtConcurrent::run(this, &UpgradeLookupProcess::checkUpgrades));
    }
}

void UpgradeLookupProcess::checkUpgrades()
{
    m_toCheck->checkForUpgrades(m_results, QList<const Repository *>() << m_upgradeSource);
}

UpgradeLookup::UpgradeLookup(const Manager &manager, const QJsonObject &request, QObject *parent) :
    QObject(parent),
    m_request(request),
    m_toCheck(nullptr),
    m_remainingProcesses(0),
    m_firstFinished(false)
{
    const auto toCheckName = request.value(QStringLiteral("db")).toString();
    if((m_toCheck = manager.repositoryByName(toCheckName))) {
        // construct upgrade lookup processes
        const auto syncDbsArray = request.value(QStringLiteral("syncdbs")).toArray();
        if(syncDbsArray.isEmpty()) {
            for(const auto *src : m_toCheck->upgradeSources()) {
                new UpgradeLookupProcess(this, src);
                ++m_remainingProcesses;
            }
        } else {
            for(const auto &syncDbValue : syncDbsArray) {
                const auto syncDbName = syncDbValue.toString();
                if(const auto *src = manager.repositoryByName(syncDbName)) {
                    new UpgradeLookupProcess(this, src);
                    ++m_remainingProcesses;
                } else {
                    m_warningsArray << QStringLiteral("The specified upgrade source \"%1\" can not be found.").arg(syncDbName);
                }
            }
        }
        // check whether any processes could be constructed
        if(!m_remainingProcesses) {
            m_errorsArray << QStringLiteral("No upgrade sources associated for repository \"%1\".").arg(m_toCheck->name());
        } else {
            return; // no errors so far
        }
    } else {
        m_errorsArray << QStringLiteral("Repository \"%1\" can not be found.").arg(toCheckName);
    }
    // there are errors
    QJsonObject results;
    results.insert(QStringLiteral("errors"), m_errorsArray);
    emit resultsAvailable(request.value(QStringLiteral("what")), request.value(QStringLiteral("id")), results);
    deleteLater();
}

void UpgradeLookup::processFinished()
{
    assert(m_remainingProcesses);
    // add results
    const auto &results = static_cast<UpgradeLookupProcess *>(sender())->results();
    for(const auto pkg : results.newVersions) {
        m_softwareUpdatesArray << pkg.json();
    }
    for(const auto pkg : results.newReleases) {
        m_packageOnlyUpdatesArray << pkg.json();
    }
    for(const auto pkg : results.downgrades) {
        m_downgradesArray << pkg.json();
    }
    for(const auto &warning : results.warnings) {
        m_warningsArray << warning;
    }
    for(const auto &error : results.errors) {
        m_errorsArray << error;
    }
    if(m_firstFinished) {
        m_orphanedPackages = m_orphanedPackages.intersect(results.orphaned);
    } else {
        m_firstFinished = true;
        m_orphanedPackages = results.orphaned;
    }
    // check whether all processes are finished
    if(--m_remainingProcesses == 0) {
        // finally make info for orphanded packages
        for(const auto *pkg : m_orphanedPackages) {
            m_orphanedPackagesArray << pkg->basicInfo(true);
        }
        // add results to results QJsonObject
        QJsonObject results;
        results.insert(QStringLiteral("softwareUpdates"), m_softwareUpdatesArray);
        results.insert(QStringLiteral("packageOnlyUpdates"), m_packageOnlyUpdatesArray);
        results.insert(QStringLiteral("downgrades"), m_downgradesArray);
        results.insert(QStringLiteral("orphanedPackages"), m_orphanedPackagesArray);
        if(!m_warningsArray.isEmpty()) {
            results.insert(QStringLiteral("warnings"), m_warningsArray);
        }
        if(!m_errorsArray.isEmpty()) {
            results.insert(QStringLiteral("errors"), m_errorsArray);
        }
        emit resultsAvailable(m_request.value(QStringLiteral("what")), m_request.value(QStringLiteral("id")), results);
        // lookup done, delete this helper object
        deleteLater();
    }
}

} // namespace PackageManagement