/* Copyright 2013-2019 MultiMC Contributors
 *
 * 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 <cassert>

#include <QObject>
#include "QObjectPtr.h"
#include <QDateTime>
#include <QSet>
#include <QProcess>

#include "settings/SettingsObject.h"

#include "settings/INIFile.h"
#include "BaseVersionList.h"
#include "minecraft/auth/MojangAccount.h"
#include "MessageLevel.h"
#include "pathmatcher/IPathMatcher.h"

#include "net/Mode.h"

#include "multimc_logic_export.h"

class QDir;
class Task;
class LaunchTask;
class BaseInstance;

// pointer for lazy people
typedef std::shared_ptr<BaseInstance> InstancePtr;

/*!
 * \brief Base class for instances.
 * This class implements many functions that are common between instances and
 * provides a standard interface for all instances.
 *
 * To create a new instance type, create a new class inheriting from this class
 * and implement the pure virtual functions.
 */
class MULTIMC_LOGIC_EXPORT BaseInstance : public QObject, public std::enable_shared_from_this<BaseInstance>
{
    Q_OBJECT
protected:
    /// no-touchy!
    BaseInstance(SettingsObjectPtr globalSettings, SettingsObjectPtr settings, const QString &rootDir);

public: /* types */
    enum class Status
    {
        Present,
        Gone // either nuked or invalidated
    };

public:
    /// virtual destructor to make sure the destruction is COMPLETE
    virtual ~BaseInstance() {};

    virtual void saveNow() = 0;

    /***
     * the instance has been invalidated - it is no longer tracked by MultiMC for some reason,
     * but it has not necessarily been deleted.
     *
     * Happens when the instance folder changes to some other location, or the instance is removed by external means.
     */
    void invalidate();

    /// The instance's ID. The ID SHALL be determined by MMC internally. The ID IS guaranteed to
    /// be unique.
    virtual QString id() const;

    void setRunning(bool running);
    bool isRunning() const;
    int64_t totalTimePlayed() const;
    void resetTimePlayed();

    /// get the type of this instance
    QString instanceType() const;

    /// Path to the instance's root directory.
    QString instanceRoot() const;

    /// Path to the instance's game root directory.
    virtual QString gameRoot() const
    {
        return instanceRoot();
    }

    QString name() const;
    void setName(QString val);

    /// Value used for instance window titles
    QString windowTitle() const;

    QString iconKey() const;
    void setIconKey(QString val);

    QString notes() const;
    void setNotes(QString val);

    QString getPreLaunchCommand();
    QString getPostExitCommand();
    QString getWrapperCommand();

    /// guess log level from a line of game log
    virtual MessageLevel::Enum guessLevel(const QString &line, MessageLevel::Enum level)
    {
        return level;
    };

    virtual QStringList extraArguments() const;

    /// Traits. Normally inside the version, depends on instance implementation.
    virtual QSet <QString> traits() const = 0;

    /**
     * Gets the time that the instance was last launched.
     * Stored in milliseconds since epoch.
     */
    qint64 lastLaunch() const;
    /// Sets the last launched time to 'val' milliseconds since epoch
    void setLastLaunch(qint64 val = QDateTime::currentMSecsSinceEpoch());

    /*!
     * \brief Gets this instance's settings object.
     * This settings object stores instance-specific settings.
     * \return A pointer to this instance's settings object.
     */
    virtual SettingsObjectPtr settings() const;

    /// returns a valid update task
    virtual shared_qobject_ptr<Task> createUpdateTask(Net::Mode mode) = 0;

    /// returns a valid launcher (task container)
    virtual shared_qobject_ptr<LaunchTask> createLaunchTask(AuthSessionPtr account) = 0;

    /// returns the current launch task (if any)
    shared_qobject_ptr<LaunchTask> getLaunchTask();

    /*!
     * Create envrironment variables for running the instance
     */
    virtual QProcessEnvironment createEnvironment() = 0;

    /*!
     * Returns a matcher that can maps relative paths within the instance to whether they are 'log files'
     */
    virtual IPathMatcher::Ptr getLogFileMatcher() = 0;

    /*!
     * Returns the root folder to use for looking up log files
     */
    virtual QString getLogFileRoot() = 0;

    virtual QString getStatusbarDescription() = 0;

    /// FIXME: this really should be elsewhere...
    virtual QString instanceConfigFolder() const = 0;

    /// get variables this instance exports
    virtual QMap<QString, QString> getVariables() const = 0;

    virtual QString typeName() const = 0;

    bool hasVersionBroken() const
    {
        return m_hasBrokenVersion;
    }
    void setVersionBroken(bool value)
    {
        if(m_hasBrokenVersion != value)
        {
            m_hasBrokenVersion = value;
            emit propertiesChanged(this);
        }
    }

    bool hasUpdateAvailable() const
    {
        return m_hasUpdate;
    }
    void setUpdateAvailable(bool value)
    {
        if(m_hasUpdate != value)
        {
            m_hasUpdate = value;
            emit propertiesChanged(this);
        }
    }

    bool hasCrashed() const
    {
        return m_crashed;
    }
    void setCrashed(bool value)
    {
        if(m_crashed != value)
        {
            m_crashed = value;
            emit propertiesChanged(this);
        }
    }

    virtual bool canLaunch() const;
    virtual bool canEdit() const = 0;
    virtual bool canExport() const = 0;

    bool reloadSettings();

    /**
     * 'print' a verbose desription of the instance into a QStringList
     */
    virtual QStringList verboseDescription(AuthSessionPtr session) = 0;

    Status currentStatus() const;

    int getConsoleMaxLines() const;
    bool shouldStopOnConsoleOverflow() const;

protected:
    void changeStatus(Status newStatus);

signals:
    /*!
     * \brief Signal emitted when properties relevant to the instance view change
     */
    void propertiesChanged(BaseInstance *inst);

    void launchTaskChanged(shared_qobject_ptr<LaunchTask>);

    void runningStatusChanged(bool running);

    void statusChanged(Status from, Status to);

protected slots:
    void iconUpdated(QString key);

protected: /* data */
    QString m_rootDir;
    SettingsObjectPtr m_settings;
    // InstanceFlags m_flags;
    bool m_isRunning = false;
    shared_qobject_ptr<LaunchTask> m_launchProcess;
    QDateTime m_timeStarted;

private: /* data */
    Status m_status = Status::Present;
    bool m_crashed = false;
    bool m_hasUpdate = false;
    bool m_hasBrokenVersion = false;
};

Q_DECLARE_METATYPE(shared_qobject_ptr<BaseInstance>)
//Q_DECLARE_METATYPE(BaseInstance::InstanceFlag)
//Q_DECLARE_OPERATORS_FOR_FLAGS(BaseInstance::InstanceFlags)