/*

    This file is part of the KFloppy program, part of the KDE project
    
    Copyright (C) 2002 Adriaan de Groot <groot@kde.org>
    Copyright (C) 2004, 2005 Nicolas GOUTTE <goutte@kde.org>
    Copyright (C) 2015, 2016 Wolfgang Bauer <wbauer@tmo.at>


    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, version 2.

    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 FORMAT_H
#define FORMAT_H

/** \file format.h
 * This file defines a hierarchy of classes that
 * can run a sequence of external programs (like
 * fdformat, mkisofs, etc.) in sequence. Stdout
 * and stderr of those programs can be captured
 * and analyzed in order to provide feedback to
 * the user.
 *
 * <ul>
 * <li>KFAction:           Base class, just for performing some action.
 * <li>KFActionQueue:     Provides sequencing of KFActions
 * <li>FloppyAction:      Weird name; handles running a program,
 *                     understands FD device names. This can be
 *                     considered the "useful" base class of
 *                     programming actions.
 * <li>FDFormat:        Runs fdformat(1) under BSD or Linux.
 * <li>FATFilesystem:   Creates an msdos (FAT) filesystem.
 * <li>Ext2Filesystem:  Creates ext2 filesystems.
 * <li>MinixFilesystem: Creates Minix filesystems, under Linux.
 * <li>UFSFilesystem:   Creates UFS filesystem, under BSD.
 * </ul>
 *
 * \note Maybe this is overkill, since for floppies all you need is
 * fdformat(1) and some create-filesystem program like newfs(1)
 * or mke2fs(1). However, for Zip disks, should they ever be supported,
 * this is quite useful since you need to dd, fdisk, disklabel, and
 * newfs them.
*/

#include "debug.h"
#include <QObject>
#include <QProcess>

/**
 * \brief Abstract base class of actions to be undertaken.
 *
 * Basically you can create a KFActionStack (See below)
 * and push a bunch of actions on it, then run exec()
 * on the stack and wait for the done() signal.
*/
class KFAction : public QObject
{
Q_OBJECT

public:
	explicit KFAction(QObject *parent = nullptr);
	virtual ~KFAction();
	
public Q_SLOTS:
	/**
	 * Exec() should return quickly to ensure that the GUI
	 * thread stays alive. quit() should abort the action.
	 */
	virtual void exec();
	/**
	 * Quit aborts the action. No done() signal should
	 * be emitted.
	 */
	virtual void quit();
	
Q_SIGNALS:
	/**
	 * done() should always be emitted with this as first
	 * parameter, to avoid sender() magic and the like.
	 * @p success indicates whether the action was
	 * successful.
	 */
	void done(KFAction *me,bool success);

	/**
	 * Emit this signal to inform the user of interesting
	 * changes; setting msg to an empty string doesn't
	 * change any visible user message. @p progress
	 * indicates the action's progress (if that can be determined)
	 * and sending -1 leaves the visible indicator unchanged.
	 */
	void status(const QString &msg, int progress);

        /** error() displays a box. It interrupts
	 * the user's work and should be used with care.
	 */
	void error(const QString &msg, const QString &details);
} ;


/**
 * Acts as a queue and executes the actions in the
 * queue in FIFO order.
 */
class KFActionQueue : public KFAction
{
Q_OBJECT

public:
	explicit KFActionQueue(QObject *parent = nullptr);
	virtual ~KFActionQueue();
	
	/**
	 * Add a KFAction to the queue. When exec() is called,
	 * the actions are called one after the other (if each
	 * action is successful; if any action fails, the whole
	 * queue fails and the unsuccessful action is the last
	 * one run.) Actions become the property of the queue
	 * action. Note that queues can be nested.
	 */
	void queue(KFAction *);
	
	void exec() override;

protected Q_SLOTS:
	void actionDone(KFAction *,bool);
	
private:
	class KFActionQueue_p *d;
} ;


/*
** The remainder of the Actions are concrete ones and
** might better go off to live in another header file,
** but this is only needed if the number of supported
** formats grows enormously.
*/

/**
 * Description structure for floppy devices.
 * devices is a list of possible device names (yay
 * /dev/ consistency) while drive,blocks denotes
 * fd0 or fd1, and the size of the disk (ought to
 * be 1440, 1200, 720 or 360. I've never seen a 2880
 * floppy drive).
 *
 * Tracks is pretty bogus; see the internal code for its use.
 * Similarly, flags are internal too.
 */

typedef struct { const char * const * devices;
	int drive;
	int blocks;
	int tracks;
	int flags; } fdinfo;

class KProcess;

/**
 * Concrete action for running a single external program.
 */

class FloppyAction : public KFAction
{
Q_OBJECT

public:
	explicit FloppyAction(QObject *parent = nullptr);
	
	/**
	 * Kills the running process, if one exists.
	 */
    void quit() override;
	
	/**
	 * ConfigureDevice() needs to be called prior to exec()
	 * or exec() will fail; this indicates which drive and
	 * density to use.
         *
         * \param driveno Number of drive (0 or 1)
         * \param density Floppy density (in Kilobytes)
         * \note This same function needs to be
	 * called on all subclasses in order to configure them
	 * for which drive to use, _along_ with their local
	 * configuration functions.
	 */
	
	bool configureDevice(int driveno, int density );

        /**
         * \brief Configure the device with a device name
         *
         * This is an alternate to FloppyAction::configureDevice
         * for user-given devices.
         *
         * \note It does not work for each type of FloppyAction yet
         */
        bool configureDevice( const QString& newDeviceName );
        
protected:
	const fdinfo *deviceInfo;      ///< Configuration info (Pointer into list of "/dev/..." entries)
	QString deviceName;  ///< Name of the device

protected Q_SLOTS:
        /**
         * \brief Provide handling of the exit of the external program
         */
	virtual void processDone(int, QProcess::ExitStatus);
	/**
         * \brief Provide handling of stdout
         */
	virtual void processStdOut(const QString &s);
	/**
         * \brief Provide handling stderr.
         *
	 * The default implementation just sends stderr on
	 * to processStdOut(), so you need reimplement only
	 * FloppyAction::processStdOut if you choose.
	 */
	virtual void processStdErr(const QString &s);
	
protected:
	KProcess *theProcess;
	QString theProcessName;  ///< human-readable

	/**
	 * Sets up connections, calls KProcess::start().
	 * You need to *theProcess << program << args ; first.
	 */
		
	bool startProcess();
private Q_SLOTS:
	/**
	 * These functions read stdout/stderr and call
	 * processStdOut()/processStdErr() accordingly
	 */
	void readStdOut();
	void readStdErr();
} ;

/**
 * Concrete class that runs fdformat(1)
 */

class FDFormat : public FloppyAction
{
public:
	explicit FDFormat(QObject *parent = nullptr);
	
	void exec() override;

	
	/**
	 * Concrete classes can provide a runtimeCheck
	 * function (heck, this is static, so the name
	 * is up to you) that checks if the required
	 * applications are available. This way, the
	 * calling application can decide not to use
	 * actions whose prerequisites are absent anyway.
	 */
	static bool runtimeCheck();
		
	/** @p verify instructs fdformat(1) to verify the
	 * medium as well.
	 */
	
	bool configure(bool verify);
	
    void processStdOut(const QString &s) override;

protected:
	static QString fdformatName;    ///< path to executable.
	int formatTrackCount;    ///< How many tracks formatted.
	bool doVerify;
} ;

/**
 * Zero out disk by running dd(1)
 * \bug As dd terminates with the error "No space left on device", KFloppy aborts
 */
class DDZeroOut : public FloppyAction
{
public:
    explicit DDZeroOut(QObject *parent = nullptr);

    void exec() override;

    /**
     * Concrete classes can provide a runtimeCheck
     * function (heck, this is static, so the name
     * is up to you) that checks if the required
     * applications are available. This way, the
     * calling application can decide not to use
     * actions whose prerequisites are absent anyway.
     */
    static bool runtimeCheck();           

protected:
    /**
     * \brief Provide handling of the exit of the external program
     */
    void processDone(int exitCode, QProcess::ExitStatus exitStatus) override;
protected:
    static QString m_ddName;    ///< path to executable.
} ;


/**
 * Create an msdos (FAT) filesystem on the floppy.
 */
class FATFilesystem : public FloppyAction
{
public:
	explicit FATFilesystem(QObject *parent = nullptr);
	
	void exec() override;
	
	static bool runtimeCheck();

	/**
	 * newfs_msdos(1) doesn't support an additional verify,
	 * but Linux mkdosfs(1) does. Enable additional medium
	 * verify with @p verify. Disks can be labeled (@p label) with the
	 * remaining parameters (@p l).
	 */	
	bool configure(bool verify, bool label, const QString &l);
	
        /// Parse output
        void processStdOut(const QString &s) override;
        
protected:
	static QString newfs_fat;
	
	bool doVerify,doLabel;
	QString label;
	
} ;

/**
 * Format with Ext2
 */
class Ext2Filesystem : public FloppyAction
{
public:
	explicit Ext2Filesystem(QObject *parent = nullptr);
	
	void exec() override;
	
	static bool runtimeCheck();
	
	/// Same args as FATFilesystem::configure
	bool configure(bool verify, bool label, const QString &l);

        /// Parse output
        void processStdOut(const QString &s) override;
	
protected:
	static QString newfs;
	
	bool doVerify,doLabel;
	QString label;
} ;

#ifdef ANY_BSD

/**
 * \brief Format with UFS
 * \note BSD only
 */
class UFSFilesystem : public FloppyAction
{
public:
	explicit UFSFilesystem(QObject *parent = nullptr);
	
	void exec() override;
	
	static bool runtimeCheck();
	
protected:
	static QString newfs;
	
	bool doVerify,doLabel;
	QString label;
} ;
#endif

#ifdef ANY_LINUX
/**
 * \brief Format with Minix
 * \note Linux only
 */
class MinixFilesystem : public FloppyAction
{
public:
	explicit MinixFilesystem(QObject *parent = nullptr);
	
   	void exec() override;

	static bool runtimeCheck();
	
	/// Same args as FATFilesystem::configure
	bool configure(bool verify, bool label, const QString &l);
        
        /// Parse output
        void processStdOut(const QString &s) override;
protected:
	static QString newfs;
	
	bool doVerify,doLabel;
	QString label;
} ;
#endif

/**
 * Utility function that looks for executables in $PATH
 * and in /sbin and /usr/sbin.
 */

QString findExecutable(const QString &);

#endif