/*
    This file is part of Konsole, an X terminal.

    Copyright 2007-2008 by Robert Knight <robertknight@gmail.com>
    Copyright 1997,1998 by Lars Doelle <lars.doelle@on-line.de>
    Copyright 2009 by Thomas Dreibholz <dreibh@iem.uni-due.de>

    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 2 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, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301  USA.
*/

#ifndef SESSION_H
#define SESSION_H

// Qt
#include <QtCore/QStringList>
#include <QtCore/QHash>
//#include <QtCore/QByteRef>
#include <QtCore/QUuid>
#include <QtCore/QSize>
#include <QtCore/QProcess>
#include <QWidget>

// KDE
#include <KUrl>

// Konsole
#include "konsole_export.h"

class QColor;

class KConfigGroup;
class KProcess;

namespace Konsole
{
class Emulation;
class Pty;
class ProcessInfo;
class TerminalDisplay;
class ZModemDialog;
class HistoryType;

/**
 * Platform-specific main shortcut "opcode":
 */
enum Modifier {
#ifdef Q_OS_MAC
    ACCEL = Qt::META
#else
    ACCEL = Qt::CTRL
#endif
};

/**
 * Represents a terminal session consisting of a pseudo-teletype and a terminal emulation.
 * The pseudo-teletype (or PTY) handles I/O between the terminal process and Konsole.
 * The terminal emulation ( Emulation and subclasses ) processes the output stream from the
 * PTY and produces a character image which is then shown on views connected to the session.
 *
 * Each Session can be connected to one or more views by using the addView() method.
 * The attached views can then display output from the program running in the terminal
 * or send input to the program in the terminal in the form of keypresses and mouse
 * activity.
 */
class KONSOLEPRIVATE_EXPORT Session : public QObject
{
    Q_OBJECT
    Q_CLASSINFO("D-Bus Interface", "org.kde.konsole.Session")

public:
    Q_PROPERTY(QString name READ nameTitle)
    Q_PROPERTY(int processId READ processId)
    Q_PROPERTY(QString keyBindings READ keyBindings WRITE setKeyBindings)
    Q_PROPERTY(QSize size READ size WRITE setSize)

    /**
     * Constructs a new session.
     *
     * To start the terminal process, call the run() method,
     * after specifying the program and arguments
     * using setProgram() and setArguments()
     *
     * If no program or arguments are specified explicitly, the Session
     * falls back to using the program specified in the SHELL environment
     * variable.
     */
    explicit Session(QObject* parent = 0);
    ~Session();

    /**
     * Connect to an existing terminal.  When a new Session() is constructed it
     * automatically searches for and opens a new teletype.  If you want to
     * use an existing teletype (given its file descriptor) call this after
     * constructing the session.
     *
     * Calling openTeletype() while a session is running has no effect.
     *
     * @param masterFd The file descriptor of the pseudo-teletype master (See KPtyProcess::KPtyProcess())
     */
    void openTeletype(int masterFd);

    /**
     * Returns true if the session is currently running.  This will be true
     * after run() has been called successfully.
     */
    bool isRunning() const;

    /**
     * Adds a new view for this session.
     *
     * The viewing widget will display the output from the terminal and
     * input from the viewing widget (key presses, mouse activity etc.)
     * will be sent to the terminal.
     *
     * Views can be removed using removeView().  The session is automatically
     * closed when the last view is removed.
     */
    void addView(TerminalDisplay* widget);
    /**
     * Removes a view from this session.  When the last view is removed,
     * the session will be closed automatically.
     *
     * @p widget will no longer display output from or send input
     * to the terminal
     */
    void removeView(TerminalDisplay* widget);

    /**
     * Returns the views connected to this session
     */
    QList<TerminalDisplay*> views() const;

    /**
     * Returns the terminal emulation instance being used to encode / decode
     * characters to / from the process.
     */
    Emulation*  emulation() const;

    /** Returns the unique ID for this session. */
    int sessionId() const;

    /**
     * This enum describes the contexts for which separate
     * tab title formats may be specified.
     */
    enum TabTitleContext {
        /** Default tab title format */
        LocalTabTitle,
        /**
         * Tab title format used session currently contains
         * a connection to a remote computer (via SSH)
         */
        RemoteTabTitle
    };

    /**
     * Returns true if the session currently contains a connection to a
     * remote computer.  It currently supports ssh.
     */
    bool isRemote();

    /**
     * Sets the format used by this session for tab titles.
     *
     * @param context The context whose format should be set.
     * @param format The tab title format.  This may be a mixture
     * of plain text and dynamic elements denoted by a '%' character
     * followed by a letter.  (eg. %d for directory).  The dynamic
     * elements available depend on the @p context
     */
    void setTabTitleFormat(TabTitleContext context , const QString& format);
    /** Returns the format used by this session for tab titles. */
    QString tabTitleFormat(TabTitleContext context) const;

    /** Returns the arguments passed to the shell process when run() is called. */
    QStringList arguments() const;
    /** Returns the program name of the shell process started when run() is called. */
    QString program() const;

    /**
     * Sets the command line arguments which the session's program will be passed when
     * run() is called.
     */
    void setArguments(const QStringList& arguments);
    /** Sets the program to be executed when run() is called. */
    void setProgram(const QString& program);

    /** Returns the session's current working directory. */
    QString initialWorkingDirectory() {
        return _initialWorkingDir;
    }

    /**
     * Sets the initial working directory for the session when it is run
     * This has no effect once the session has been started.
     */
    void setInitialWorkingDirectory(const QString& dir);

    /**
     * Returns the current directory of the foreground process in the session
     */
    QString currentWorkingDirectory();

    /**
     * Sets the type of history store used by this session.
     * Lines of output produced by the terminal are added
     * to the history store.  The type of history store
     * used affects the number of lines which can be
     * remembered before they are lost and the storage
     * (in memory, on-disk etc.) used.
     */
    void setHistoryType(const HistoryType& type);
    /**
     * Returns the type of history store used by this session.
     */
    const HistoryType& historyType() const;
    /**
     * Clears the history store used by this session.
     */
    void clearHistory();

    /**
     * Sets the key bindings used by this session.  The bindings
     * specify how input key sequences are translated into
     * the character stream which is sent to the terminal.
     *
     * @param name The name of the key bindings to use.  The
     * names of available key bindings can be determined using the
     * KeyboardTranslatorManager class.
     */
    void setKeyBindings(const QString& name);
    /** Returns the name of the key bindings used by this session. */
    QString keyBindings() const;

    /**
     * This enum describes the available title roles.
     */
    enum TitleRole {
        /** The name of the session. */
        NameRole,
        /** The title of the session which is displayed in tabs etc. */
        DisplayedTitleRole
    };

    /**
     * Return the session title set by the user (ie. the program running
     * in the terminal), or an empty string if the user has not set a custom title
     */
    QString userTitle() const;

    /** Convenience method used to read the name property.  Returns title(Session::NameRole). */
    QString nameTitle() const {
        return title(Session::NameRole);
    }
    /** Returns a title generated from tab format and process information. */
    QString getDynamicTitle();

    /** Sets the name of the icon associated with this session. */
    void setIconName(const QString& iconName);
    /** Returns the name of the icon associated with this session. */
    QString iconName() const;

    /** Return URL for the session. */
    KUrl getUrl();

    /** Sets the text of the icon associated with this session. */
    void setIconText(const QString& iconText);
    /** Returns the text of the icon associated with this session. */
    QString iconText() const;

    /** Sets the session's title for the specified @p role to @p title. */
    void setTitle(TitleRole role , const QString& title);

    /** Returns the session's title for the specified @p role. */
    QString title(TitleRole role) const;

    /**
     * Specifies whether a utmp entry should be created for the pty used by this session.
     * If true, KPty::login() is called when the session is started.
     */
    void setAddToUtmp(bool);

    /**
     * Specifies whether to close the session automatically when the terminal
     * process terminates.
     */
    void setAutoClose(bool close);

    /** See setAutoClose() */
    bool autoClose() const;

    /** Returns true if the user has started a program in the session. */
    bool isForegroundProcessActive();

    /** Returns the name of the current foreground process. */
    QString foregroundProcessName();

    /** Returns the terminal session's window size in lines and columns. */
    QSize size();
    /**
     * Emits a request to resize the session to accommodate
     * the specified window size.
     *
     * @param size The size in lines and columns to request.
     */
    void setSize(const QSize& size);

    QSize preferredSize() const;

    void setPreferredSize(const QSize & size);

    /**
     * Sets whether the session has a dark background or not.  The session
     * uses this information to set the COLORFGBG variable in the process's
     * environment, which allows the programs running in the terminal to determine
     * whether the background is light or dark and use appropriate colors by default.
     *
     * This has no effect once the session is running.
     */
    void setDarkBackground(bool darkBackground);

    /**
     * Attempts to get the shell program to redraw the current display area.
     * This can be used after clearing the screen, for example, to get the
     * shell to redraw the prompt line.
     */
    void refresh();

    void startZModem(const QString& rz, const QString& dir, const QStringList& list);
    void cancelZModem();
    bool isZModemBusy() {
        return _zmodemBusy;
    }

    /**
      * Possible values of the @p what parameter for setUserTitle()
      * See "Operating System Controls" section on http://rtfm.etla.org/xterm/ctlseq.html
      */
    enum UserTitleChange {
        IconNameAndWindowTitle = 0,
        IconName               = 1,
        WindowTitle            = 2,
        TextColor              = 10,
        BackgroundColor        = 11,
        SessionName            = 30,  // Non-standard
        SessionIcon            = 32,  // Non-standard
        ProfileChange          = 50   // this clashes with Xterm's font change command
    };

    // Sets the text codec used by this sessions terminal emulation.
    void setCodec(QTextCodec* codec);

    // session management
    void saveSession(KConfigGroup& group);
    void restoreSession(KConfigGroup& group);

    void sendSignal(int signal);

public slots:

    /**
     * Starts the terminal session.
     *
     * This creates the terminal process and connects the teletype to it.
     */
    void run();

    /**
     * Returns the environment of this session as a list of strings like
     * VARIABLE=VALUE
     */
    Q_SCRIPTABLE QStringList environment() const;

    /**
     * Sets the environment for this session.
     * @p environment should be a list of strings like
     * VARIABLE=VALUE
     */
    Q_SCRIPTABLE void setEnvironment(const QStringList& environment);

    /**
     * Adds one entry for the environment of this session
     * @p entry should be like VARIABLE=VALUE
     */
    void addEnvironmentEntry(const QString& entry);

    /**
     * Closes the terminal session. It kills the terminal process by calling
     * closeInNormalWay() and, optionally, closeInForceWay().
     */
    //Q_SCRIPTABLE void close(); // This cause the menu issues bko 185466
    void close();

    /**
     * Kill the terminal process in normal way. This sends a hangup signal
     * (SIGHUP) to the terminal process and causes the finished() signal to
     * be emitted. If the process does not respond to the SIGHUP signal then
     * the terminal connection (the pty) is closed and Konsole waits for the
     * process to exit. This method works most of the time, but fails with some
     * programs which respond to SIGHUP signal in special way, such as autossh
     * and irssi.
     */
    bool closeInNormalWay();

    /**
     * kill terminal process in force way. This send a SIGKILL signal to the
     * terminal process. It should be called only after closeInNormalWay() has
     * failed. Take it as last resort.
     */
    bool closeInForceWay();

    /**
     * Changes the session title or other customizable aspects of the terminal
     * emulation display. For a list of what may be changed see the
     * Emulation::titleChanged() signal.
     *
     * @param what The feature being changed.  Value is one of UserTitleChange
     * @param caption The text part of the terminal command
     */
    void setUserTitle(int what , const QString& caption);

    /**
     * Enables monitoring for activity in the session.
     * This will cause notifySessionState() to be emitted
     * with the NOTIFYACTIVITY state flag when output is
     * received from the terminal.
     */
    Q_SCRIPTABLE void setMonitorActivity(bool);

    /** Returns true if monitoring for activity is enabled. */
    Q_SCRIPTABLE bool isMonitorActivity() const;

    /**
     * Enables monitoring for silence in the session.
     * This will cause notifySessionState() to be emitted
     * with the NOTIFYSILENCE state flag when output is not
     * received from the terminal for a certain period of
     * time, specified with setMonitorSilenceSeconds()
     */
    Q_SCRIPTABLE void setMonitorSilence(bool);

    /**
     * Returns true if monitoring for inactivity (silence)
     * in the session is enabled.
     */
    Q_SCRIPTABLE bool isMonitorSilence() const;

    /** See setMonitorSilence() */
    Q_SCRIPTABLE void setMonitorSilenceSeconds(int seconds);

    /**
     * Sets whether flow control is enabled for this terminal
     * session.
     */
    Q_SCRIPTABLE void setFlowControlEnabled(bool enabled);

    /** Returns whether flow control is enabled for this terminal session. */
    Q_SCRIPTABLE bool flowControlEnabled() const;

    /**
     * Sends @p text to the current foreground terminal program.
     */
    Q_SCRIPTABLE void sendText(const QString& text) const;

    /**
     * Sends @p command to the current foreground terminal program.
     */
    Q_SCRIPTABLE void runCommand(const QString& command) const;

    /**
     * Sends a mouse event of type @p eventType emitted by button
     * @p buttons on @p column/@p line to the current foreground
     * terminal program
     */
    Q_SCRIPTABLE void sendMouseEvent(int buttons, int column, int line, int eventType);

    /**
    * Returns the process id of the terminal process.
    * This is the id used by the system API to refer to the process.
    */
    Q_SCRIPTABLE int processId() const;

    /**
     * Returns the process id of the terminal's foreground process.
     * This is initially the same as processId() but can change
     * as the user starts other programs inside the terminal.
     */
    Q_SCRIPTABLE int foregroundProcessId();

    /** Sets the text codec used by this sessions terminal emulation.
      * Overloaded to accept a QByteArray for convenience since DBus
      * does not accept QTextCodec directly.
      */
    Q_SCRIPTABLE bool setCodec(QByteArray codec);

    /** Returns the codec used to decode incoming characters in this
     * terminal emulation
     */
    Q_SCRIPTABLE QByteArray codec();

    /** Sets the session's title for the specified @p role to @p title.
     *  This is an overloaded member function for setTitle(TitleRole, QString)
     *  provided for convenience since enum data types may not be
     *  exported directly through DBus
     */
    Q_SCRIPTABLE void setTitle(int role, const QString& title);

    /** Returns the session's title for the specified @p role.
     * This is an overloaded member function for  setTitle(TitleRole)
     * provided for convenience since enum data types may not be
     * exported directly through DBus
     */
    Q_SCRIPTABLE QString title(int role) const;

    /** Returns the "friendly" version of the QUuid of this session.
    * This is a QUuid with the braces and dashes removed, so it cannot be
    * used to construct a new QUuid. The same text appears in the
    * SHELL_SESSION_ID environment variable.
    */
    Q_SCRIPTABLE QString shellSessionId() const;

    /** Sets the session's tab title format for the specified @p context to @p format.
     *  This is an overloaded member function for setTabTitleFormat(TabTitleContext, QString)
     *  provided for convenience since enum data types may not be
     *  exported directly through DBus
     */
    Q_SCRIPTABLE void setTabTitleFormat(int context, const QString& format);

    /** Returns the session's tab title format for the specified @p context.
     * This is an overloaded member function for tabTitleFormat(TitleRole)
     * provided for convenience since enum data types may not be
     * exported directly through DBus
     */
    Q_SCRIPTABLE QString tabTitleFormat(int context) const;

    /**
     * Sets the history capacity of this session.
     *
     * @param lines The history capacity in unit of lines. Its value can be:
     * <ul>
     * <li> positive integer  -  fixed size history</li>
     * <li> 0 -  no history</li>
     * <li> negative integer -  unlimited history</li>
     * </ul>
     */
    Q_SCRIPTABLE void setHistorySize(int lines);

    /**
     * Returns the history capacity of this session.
     */
    Q_SCRIPTABLE int historySize() const;

signals:

    /** Emitted when the terminal process starts. */
    void started();

    /**
     * Emitted when the terminal process exits.
     */
    void finished();

    /** Emitted when the session's title has changed. */
    void titleChanged();

    /**
     * Emitted when the activity state of this session changes.
     *
     * @param state The new state of the session.  This may be one
     * of NOTIFYNORMAL, NOTIFYSILENCE or NOTIFYACTIVITY
     */
    void stateChanged(int state);

    /**
     * Emitted when the current working directory of this session changes.
     *
     * @param dir The new current working directory of the session.
     */
    void currentDirectoryChanged(const QString& dir);

    /** Emitted when a bell event occurs in the session. */
    void bellRequest(const QString& message);

    /**
     * Requests that the color the text for any tabs associated with
     * this session should be changed;
     *
     * TODO: Document what the parameter does
     */
    void changeTabTextColorRequest(int);

    /**
     * Requests that the background color of views on this session
     * should be changed.
     */
    void changeBackgroundColorRequest(const QColor&);
    /**
     * Requests that the text color of views on this session should
     * be changed to @p color.
     */
    void changeForegroundColorRequest(const QColor&);

    /** TODO: Document me. */
    void openUrlRequest(const QString& url);

    /**
     * Emitted when the request for data transmission through ZModem
     * protocol is detected.
     */
    void zmodemDetected();

    /**
     * Emitted when the terminal process requests a change
     * in the size of the terminal window.
     *
     * @param size The requested window size in terms of lines and columns.
     */
    void resizeRequest(const QSize& size);

    /**
     * Emitted when a profile change command is received from the terminal.
     *
     * @param text The text of the command.  This is a string of the form
     * "PropertyName=Value;PropertyName=Value ..."
     */
    void profileChangeCommandReceived(const QString& text);

    /**
     * Emitted when the flow control state changes.
     *
     * @param enabled True if flow control is enabled or false otherwise.
     */
    void flowControlEnabledChanged(bool enabled);

    /**
     * Emitted when the active screen is switched, to indicate whether the primary
     * screen is in use.
     *
     * This signal serves as a relayer of Emulation::priamyScreenInUse(bool),
     * making it usable for higher level component.
     */
    void primaryScreenInUse(bool use);

    /**
     * Emitted when the text selection is changed.
     *
     * This signal serves as a relayer of Emulation::selectedText(QString),
     * making it usable for higher level component.
     */
    void selectionChanged(const QString& text);

private slots:
    void done(int, QProcess::ExitStatus);

    void fireZModemDetected();

    void onReceiveBlock(const char* buffer, int len);
    void silenceTimerDone();
    void activityTimerDone();

    void onViewSizeChange(int height, int width);

    void activityStateSet(int);

    //automatically detach views from sessions when view is destroyed
    void viewDestroyed(QObject* view);

    void zmodemReadStatus();
    void zmodemReadAndSendBlock();
    void zmodemReceiveBlock(const char* data, int len);
    void zmodemFinished();

    void updateFlowControlState(bool suspended);
    void updateWindowSize(int lines, int columns);

    // signal relayer
    void onPrimaryScreenInUse(bool use);

private:
    // checks that the binary 'program' is available and can be executed
    // returns the binary name if available or an empty string otherwise
    static QString checkProgram(const QString& program);

    void updateTerminalSize();
    WId windowId() const;
    bool kill(int signal);
    // print a warning message in the terminal.  This is used
    // if the program fails to start, or if the shell exits in
    // an unsuccessful manner
    void terminalWarning(const QString& message);
    ProcessInfo* getProcessInfo();
    void updateSessionProcessInfo();
    bool updateForegroundProcessInfo();
    ProcessInfo* updateWorkingDirectory();

    QUuid            _uniqueIdentifier; // SHELL_SESSION_ID

    Pty*          _shellProcess;
    Emulation*    _emulation;

    QList<TerminalDisplay*> _views;

    // monitor activity & silence
    bool           _monitorActivity;
    bool           _monitorSilence;
    bool           _notifiedActivity;
    int            _silenceSeconds;
    QTimer*        _silenceTimer;
    QTimer*        _activityTimer;

    bool           _autoClose;
    bool           _closePerUserRequest;

    QString        _nameTitle;
    QString        _displayTitle;
    QString        _userTitle;

    QString        _localTabTitleFormat;
    QString        _remoteTabTitleFormat;

    QString        _iconName;
    QString        _iconText; // not actually used
    bool           _addToUtmp;
    bool           _flowControlEnabled;

    QString        _program;
    QStringList    _arguments;

    QStringList    _environment;
    int            _sessionId;

    QString        _initialWorkingDir;
    QString        _currentWorkingDir;

    ProcessInfo*   _sessionProcessInfo;
    ProcessInfo*   _foregroundProcessInfo;
    int            _foregroundPid;

    // ZModem
    bool           _zmodemBusy;
    KProcess*      _zmodemProc;
    ZModemDialog*  _zmodemProgress;

    bool _hasDarkBackground;

    QSize _preferredSize;

    static int lastSessionId;
};

/**
 * Provides a group of sessions which is divided into master and slave sessions.
 * Activity in master sessions can be propagated to all sessions within the group.
 * The type of activity which is propagated and method of propagation is controlled
 * by the masterMode() flags.
 */
class SessionGroup : public QObject
{
    Q_OBJECT

public:
    /** Constructs an empty session group. */
    explicit SessionGroup(QObject* parent);
    /** Destroys the session group and removes all connections between master and slave sessions. */
    ~SessionGroup();

    /** Adds a session to the group. */
    void addSession(Session* session);
    /** Removes a session from the group. */
    void removeSession(Session* session);

    /** Returns the list of sessions currently in the group. */
    QList<Session*> sessions() const;

    /**
     * Sets whether a particular session is a master within the group.
     * Changes or activity in the group's master sessions may be propagated
     * to all the sessions in the group, depending on the current masterMode()
     *
     * @param session The session whose master status should be changed.
     * @param master True to make this session a master or false otherwise
     */
    void setMasterStatus(Session* session , bool master);
    /** Returns the master status of a session.  See setMasterStatus() */
    bool masterStatus(Session* session) const;

    /**
     * This enum describes the options for propagating certain activity or
     * changes in the group's master sessions to all sessions in the group.
     */
    enum MasterMode {
        /**
         * Any input key presses in the master sessions are sent to all
         * sessions in the group.
         */
        CopyInputToAll = 1
    };

    /**
     * Specifies which activity in the group's master sessions is propagated
     * to all sessions in the group.
     *
     * @param mode A bitwise OR of MasterMode flags.
     */
    void setMasterMode(int mode);
    /**
     * Returns a bitwise OR of the active MasterMode flags for this group.
     * See setMasterMode()
     */
    int masterMode() const;

private slots:
    void sessionFinished();
    void forwardData(const char* data, int size);

private:
    QList<Session*> masters() const;

    // maps sessions to their master status
    QHash<Session*, bool> _sessions;

    int _masterMode;
};
}

#endif
