#include "LegacyUpgradeTask.h"
#include "settings/INISettingsObject.h"
#include "FileSystem.h"
#include "NullInstance.h"
#include "pathmatcher/RegexpMatcher.h"
#include <QtConcurrentRun>
#include "LegacyInstance.h"
#include "minecraft/MinecraftInstance.h"
#include "minecraft/PackProfile.h"
#include "LegacyModList.h"
#include "classparser.h"

LegacyUpgradeTask::LegacyUpgradeTask(InstancePtr origInstance)
{
    m_origInstance = origInstance;
}

void LegacyUpgradeTask::executeTask()
{
    setStatus(tr("Copying instance %1").arg(m_origInstance->name()));

    FS::copy folderCopy(m_origInstance->instanceRoot(), m_stagingPath);
    folderCopy.followSymlinks(true);

    m_copyFuture = QtConcurrent::run(QThreadPool::globalInstance(), folderCopy);
    connect(&m_copyFutureWatcher, &QFutureWatcher<bool>::finished, this, &LegacyUpgradeTask::copyFinished);
    connect(&m_copyFutureWatcher, &QFutureWatcher<bool>::canceled, this, &LegacyUpgradeTask::copyAborted);
    m_copyFutureWatcher.setFuture(m_copyFuture);
}

static QString decideVersion(const QString& currentVersion, const QString& intendedVersion)
{
    if(intendedVersion != currentVersion)
    {
        if(!intendedVersion.isEmpty())
        {
            return intendedVersion;
        }
        else if(!currentVersion.isEmpty())
        {
            return currentVersion;
        }
    }
    else
    {
        if(!intendedVersion.isEmpty())
        {
            return intendedVersion;
        }
    }
    return QString();
}

void LegacyUpgradeTask::copyFinished()
{
    auto successful = m_copyFuture.result();
    if(!successful)
    {
        emitFailed(tr("Instance folder copy failed."));
        return;
    }
    auto legacyInst = std::dynamic_pointer_cast<LegacyInstance>(m_origInstance);

    auto instanceSettings = std::make_shared<INISettingsObject>(FS::PathCombine(m_stagingPath, "instance.cfg"));
    instanceSettings->registerSetting("InstanceType", "Legacy");
    instanceSettings->set("InstanceType", "OneSix");
    // NOTE: this scope ensures the instance is fully saved before we emitSucceeded
    {
        MinecraftInstance inst(m_globalSettings, instanceSettings, m_stagingPath);
        inst.setName(m_instName);

        QString preferredVersionNumber = decideVersion(legacyInst->currentVersionId(), legacyInst->intendedVersionId());
        if(preferredVersionNumber.isNull())
        {
            // try to decide version based on the jar(s?)
            preferredVersionNumber = classparser::GetMinecraftJarVersion(legacyInst->baseJar());
            if(preferredVersionNumber.isNull())
            {
                preferredVersionNumber = classparser::GetMinecraftJarVersion(legacyInst->runnableJar());
                if(preferredVersionNumber.isNull())
                {
                    emitFailed(tr("Could not decide Minecraft version."));
                    return;
                }
            }
        }
        auto components = inst.getPackProfile();
        components->buildingFromScratch();
        components->setComponentVersion("net.minecraft", preferredVersionNumber, true);

        QString jarPath = legacyInst->mainJarToPreserve();
        if(!jarPath.isNull())
        {
            qDebug() << "Preserving base jar! : " << jarPath;
            // FIXME: handle case when the jar is unreadable?
            // TODO: check the hash, if it's the same as the upstream jar, do not do this
            components->installCustomJar(jarPath);
        }

        auto jarMods = legacyInst->jarModList()->allMods();
        for(auto & jarMod: jarMods)
        {
            QString modPath = jarMod.absoluteFilePath();
            qDebug() << "jarMod: " << modPath;
            components->installJarMods({modPath});
        }

        // remove all the extra garbage we no longer need
        auto removeAll = [&](const QString &root, const QStringList &things)
        {
            for(auto &thing : things)
            {
                auto removePath = FS::PathCombine(root, thing);
                QFileInfo stat(removePath);
                if(stat.isDir())
                {
                    FS::deletePath(removePath);
                }
                else
                {
                    QFile::remove(removePath);
                }
            }
        };
        QStringList rootRemovables = {"modlist", "version", "instMods"};
        QStringList mcRemovables = {"bin", "MultiMCLauncher.jar", "icon.png"};
        removeAll(inst.instanceRoot(), rootRemovables);
        removeAll(inst.gameRoot(), mcRemovables);
    }
    emitSucceeded();
}

void LegacyUpgradeTask::copyAborted()
{
    emitFailed(tr("Instance folder copy has been aborted."));
    return;
}

