//
// Copyright (C) 2011-2012 Robert Dyer, Rico Tzschichholz
//
// This file is part of Plank.
//
// Plank 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 3 of the License, or
// (at your option) any later version.
//
// Plank 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, see <http://www.gnu.org/licenses/>.
//

namespace Plank {
  /**
   * The main class for all dock applications.  All docks should extend this class.
   * In the constructor, the string fields should be initialized to customize the dock.
   */
  public abstract class AbstractMain : Gtk.Application {
    /**
     * The default command-line options for the dock.
     */
    const OptionEntry[] options = {
      { "debug", 'd', 0, OptionArg.NONE, null, "Enable debug logging", null },
      { "verbose", 'v', 0, OptionArg.NONE, null, "Enable verbose logging", null },
      { "name", 'n', 0, OptionArg.STRING, null, "The name of this dock. Defaults to \"dock1\".", null },
      { "preferences", 0, 0, OptionArg.NONE, null, "Show preferences dialog of the just started or already running instance", null },
      { "version", 'V', 0, OptionArg.NONE, null, "Show the application's version", null },
      { null }
    };

    static void sig_handler (int sig) {
      warning ("Caught signal (%d), exiting", sig);
      GLib.Application.get_default ().quit ();
    }

    static construct
    {
      Posix.signal (Posix.Signal.INT, sig_handler);
      Posix.signal (Posix.Signal.TERM, sig_handler);
      Posix.signal (Posix.Signal.USR1, usr1_sig_handler);
    }

    /**
     * Provide USR1 signal to move dock to the active monitor.
     */
    static void usr1_sig_handler (int sig) {
      debug ("Caught signal (%d)", sig);

      unowned AbstractMain app = (AbstractMain) GLib.Application.get_default ();
      if (app == null || app.docks == null || app.docks.size == 0)
        return;

      foreach (var dock in app.docks) {
        if (dock.position_manager == null) {
          continue;
        }
        dock.position_manager.move_to_active_monitor ();
      }
    }

    /**
     * Should be Build.DATADIR
     */
    public string build_data_dir { get; construct; }
    /**
     * Should be Build.PKGDATADIR
     */
    public string build_pkg_data_dir { get; construct; }
    /**
     * Should be Build.RELEASE_NAME
     */
    public string build_release_name { get; construct; }
    /**
     * Should be Build.VERSION
     */
    public string build_version { get; construct; }
    /**
     * Should be Build.VERSION_INFO
     */
    public string build_version_info { get; construct; }

    /**
     * The displayed name of the program.
     */
    public string program_name { get; construct; }
    /**
     * The executable name of the program.
     */
    public string exec_name { get; construct; }

    /**
     * The copyright year(s).
     */
    public string app_copyright { get; construct; }
    /**
     * The (unique) dbus path for this program.
     */
    public string app_dbus { get; construct; }
    /**
     * The name of this program's icon.
     */
    public string app_icon { get; construct; }
    /**
     * The name of the launcher (.desktop file) for this program.
     */
    public string app_launcher { get; construct; }

    /**
     * The URL for this program's website.
     */
    public string main_url { get; construct set; }
    /**
     * The URL for this program's help.
     */
    public string help_url { get; construct set; }
    /**
     * The URL for translating this program.
     */
    public string translate_url { get; construct set; }

    /**
     * The list of authors (to show in about dialog).
     */
    public string[] about_authors { get; construct set; }
    /**
     * The list of documenters (to show in about dialog).
     */
    public string[] about_documenters { get; construct set; }
    /**
     * The list of artists (to show in about dialog).
     */
    public string[] about_artists { get; construct set; }
    /**
     * The list of translators (to show in about dialog).
     */
    public string about_translators { get; construct set; }
    /**
     * The license of this program (to show in about dialog).
     */
    public Gtk.License about_license_type { get; construct set; default = Gtk.License.UNKNOWN; }

    string dock_name = "";

    Gtk.AboutDialog? about_dlg;
    PreferencesWindow? preferences_dlg;
    DockController? primary_dock;
    Gee.ArrayList<DockController> docks;

    construct
    {
      flags = ApplicationFlags.HANDLES_COMMAND_LINE;
      docks = new Gee.ArrayList<DockController> ();

      // set program name
#if HAVE_SYS_PRCTL_H
      prctl (15, exec_name);
#else
      setproctitle (exec_name);
#endif
      Environment.set_prgname (exec_name);

      Intl.bindtextdomain (Build.GETTEXT_PACKAGE, Build.DATADIR + "/locale");
      Intl.bind_textdomain_codeset (Build.GETTEXT_PACKAGE, "UTF-8");

      add_main_option_entries (options);
    }

    /**
     * {@inheritDoc}
     */
    public override void activate () {
      // TODO Maybe let the dock hide/show for a visible feedback
    }

    /**
     * {@inheritDoc}
     */
    public override int handle_local_options (VariantDict options) {
      if (options.contains ("version")) {
        print ("%s\n", build_version);
        return 0;
      }

      Logger.initialize (program_name);

      if (options.contains ("verbose"))
        Logger.DisplayLevel = LogLevel.VERBOSE;
      else if (options.contains ("debug"))
        Logger.DisplayLevel = LogLevel.DEBUG;
      else
        Logger.DisplayLevel = LogLevel.INFO;

      if (options.lookup ("name", "&s", out dock_name)) {
        application_id = "%s.%s".printf (app_dbus, dock_name);
      } else {
        dock_name = "";
        application_id = app_dbus;
      }

      return -1;
    }

    /**
     * {@inheritDoc}
     */
    public override int command_line (ApplicationCommandLine command_line) {
      var options = command_line.get_options_dict ();

      if (options.contains ("preferences"))
        activate_action ("preferences", null);

      return 0;
    }

    /**
     * {@inheritDoc}
     */
    public override void startup () {
      // Make sure important properties are set
      assert (build_data_dir != null);
      assert (build_pkg_data_dir != null);
      assert (build_release_name != null);
      assert (build_version != null);
      assert (build_version_info != null);
      assert (program_name != null);
      assert (exec_name != null);
      assert (app_dbus != null);

      base.startup ();

      if (!Thread.supported ())
        critical ("Problem initializing thread support.");

      message ("%s version: %s", program_name, build_version);
      message ("Kernel version: %s", Posix.utsname ().release);
      message ("GLib version: %u.%u.%u (%u.%u.%u)",
               GLib.Version.major, GLib.Version.minor, GLib.Version.micro,
               GLib.Version.MAJOR, GLib.Version.MINOR, GLib.Version.MICRO);
      message ("GTK+ version: %u.%u.%u (%i.%i.%i)",
               Gtk.get_major_version (), Gtk.get_minor_version (), Gtk.get_micro_version (),
               Gtk.MAJOR_VERSION, Gtk.MINOR_VERSION, Gtk.MICRO_VERSION);
      message ("Wnck version: %d.%d.%d", Wnck.Version.MAJOR_VERSION, Wnck.Version.MINOR_VERSION, Wnck.Version.MICRO_VERSION);
      message ("Cairo version: %s", Cairo.version_string ());
      message ("Pango version: %s", Pango.version_string ());
      message ("+ Cairo/Gtk+ HiDPI support enabled");
#if HAVE_DBUSMENU
      message ("+ Dynamic Quicklists support enabled");
#endif
#if HAVE_BARRIERS
      message ("+ XInput Barriers support enabled");
#endif
      if (Gtk.Widget.get_default_direction () == Gtk.TextDirection.RTL)
        message ("+ RTL support enabled");

      internal_quarks_initialize ();
      environment_initialize ();

      // Make sure we are not doing silly things like trying to run in a wayland-session!
      if (environment_is_session_type (XdgSessionType.WAYLAND)) {
        critical ("Wayland environments are not supported.");
        quit ();
        return;
      }

      // Initialize FontConfig
      Gdk.pango_context_get ().get_font_map ();

      Paths.initialize (exec_name, build_pkg_data_dir);
      WindowControl.initialize ();
      DockletManager.get_default ().load_docklets ();

      initialize ();
      create_docks ();
      create_actions ();
    }

    /**
     * Additional initializations before the dock is created.
     */
    protected virtual void initialize () {
    }

    /**
     * Creates the docks.
     */
    protected virtual void create_docks () {
      if (dock_name != null && dock_name != "") {
        message ("Running with 1 dock ('%s')", dock_name);
        add_dock (create_dock (dock_name));
        return;
      }

      var settings = create_settings ("net.launchpad.plank");
      var enabled_docks = settings.get_strv ("enabled-docks");

      // Allow up to 8 docks
      if (enabled_docks.length <= 0) {
        enabled_docks = { "dock1" };
        settings.set_strv ("enabled-docks", enabled_docks);
      } else if (enabled_docks.length > 8) {
        enabled_docks = enabled_docks[0 : 8];
        settings.set_strv ("enabled-docks", enabled_docks);
      }

      message ("Running with %i docks ('%s')", enabled_docks.length, string.joinv ("', '", enabled_docks));
      foreach (unowned string dock_name in enabled_docks)
        add_dock (create_dock (dock_name));
    }

    DockController create_dock (string dock_name) {
      var config_folder = Paths.AppConfigFolder.get_child (dock_name);
      // Make sure our config-directory exists
      Paths.ensure_directory_exists (config_folder);

      var dock = new DockController (dock_name, config_folder);
      dock.initialize ();

      return dock;
    }

    void add_dock (DockController dock) {
      // Make sure to populate our primary-dock field
      if (primary_dock == null
          || (primary_dock.prefs.PinnedOnly && !dock.prefs.PinnedOnly))
        primary_dock = dock;

      docks.add (dock);
      add_window (dock.window);
    }

    void remove_dock (DockController dock) {
      if (docks.size == 1)
        return;

      remove_window (dock.window);
      docks.remove (dock);

      if (primary_dock == dock)
        primary_dock = docks[0];
    }

    /**
     * Creates the actions and adds them to this {@link GLib.Application}.
     */
    protected virtual void create_actions () {
      SimpleAction action;

      action = new SimpleAction ("help", null);
      action.activate.connect (() => {
        System.get_default ().open_uri (help_url);
      });
      add_action (action);

      action = new SimpleAction ("translate", null);
      action.activate.connect (() => {
        System.get_default ().open_uri (translate_url);
      });
      add_action (action);

      action = new SimpleAction ("preferences", null);
      action.activate.connect (() => {
        show_preferences (primary_dock);
      });
      add_action (action);

      action = new SimpleAction ("about", null);
      action.activate.connect (() => {
        show_about ();
      });
      add_action (action);

      action = new SimpleAction ("quit", null);
      action.activate.connect (() => {
        quit ();
      });
      add_action (action);
    }

    /**
     * Is true if the launcher given is the launcher for this dock.
     *
     * @param launcher the launcher to test
     */
    public bool is_launcher_for_dock (string launcher) {
      return launcher.has_suffix (app_launcher);
    }

    /**
     * Displays the about dialog.
     */
    void show_about () {
      if (about_dlg != null) {
        about_dlg.show_all ();
        return;
      }

      about_dlg = new Gtk.AboutDialog ();
      about_dlg.window_position = Gtk.WindowPosition.CENTER;
      about_dlg.gravity = Gdk.Gravity.CENTER;
      about_dlg.set_transient_for (primary_dock.window);

      about_dlg.set_program_name (exec_name);
      about_dlg.set_version ("%s\n%s".printf (build_version, build_version_info));
      about_dlg.set_logo_icon_name (app_icon);

      about_dlg.set_comments ("%s. %s".printf (program_name, build_release_name));
      about_dlg.set_copyright ("Copyright © %s %s Developers".printf (app_copyright, program_name));
      about_dlg.set_website (main_url);
      about_dlg.set_website_label ("Website");

      if (about_authors != null && about_authors.length > 0)
        about_dlg.set_authors (about_authors);
      if (about_documenters != null && about_documenters.length > 0)
        about_dlg.set_documenters (about_documenters);
      if (about_artists != null && about_artists.length > 0)
        about_dlg.set_artists (about_artists);
      if (about_translators != null && about_translators != "")
        about_dlg.set_translator_credits (about_translators);
      else
        about_dlg.set_translator_credits (_("translator-credits"));
      about_dlg.set_license_type (about_license_type);
      about_dlg.set_license ("""GNU GENERAL PUBLIC LICENSE
~~~~~~~~~~~~~~~~~~~~~~~~~~

Version 3, 29 June 2007

Copyright (C) 2007 Free Software Foundation, Inc. https://fsf.org/

Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.

Preamble
~~~~~~~~

The GNU General Public License is a free, copyleft license for software
and other kinds of works.

The licenses for most software and other practical works are designed to
take away your freedom to share and change the works. By contrast, the
GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program--to make sure it remains free
software for all its users. We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
any other work released this way by its authors. You can apply it to
your programs, too.

When we speak of free software, we are referring to freedom, not price.
Our General Public Licenses are designed to make sure that you have the
freedom to distribute copies of free software (and charge for them if
you wish), that you receive source code or can get it if you want it,
that you can change the software or use pieces of it in new free
programs, and that you know you can do these things.

To protect your rights, we need to prevent others from denying you these
rights or asking you to surrender the rights. Therefore, you have
certain responsibilities if you distribute copies of the software, or if
you modify it: responsibilities to respect the freedom of others.

For example, if you distribute copies of such a program, whether gratis
or for a fee, you must pass on to the recipients the same freedoms that
you received. You must make sure that they, too, receive or can get the
source code. And you must show them these terms so they know their
rights.

Developers that use the GNU GPL protect your rights with two steps: (1)
assert copyright on the software, and (2) offer you this License giving
you legal permission to copy, distribute and/or modify it.

For the developers' and authors' protection, the GPL clearly explains
that there is no warranty for this free software. For both users' and
authors' sake, the GPL requires that modified versions be marked as
changed, so that their problems will not be attributed erroneously to
authors of previous versions.

Some devices are designed to deny users access to install or run
modified versions of the software inside them, although the manufacturer
can do so. This is fundamentally incompatible with the aim of protecting
users' freedom to change the software. The systematic pattern of such
abuse occurs in the area of products for individuals to use, which is
precisely where it is most unacceptable. Therefore, we have designed
this version of the GPL to prohibit the practice for those products. If
such problems arise substantially in other domains, we stand ready to
extend this provision to those domains in future versions of the GPL, as
needed to protect the freedom of users.

Finally, every program is threatened constantly by software patents.
States should not allow patents to restrict development and use of
software on general-purpose computers, but in those that do, we wish to
avoid the special danger that patents applied to a free program could
make it effectively proprietary. To prevent this, the GPL assures that
patents cannot be used to render the program non-free.

The precise terms and conditions for copying, distribution and
modification follow.

TERMS AND CONDITIONS
~~~~~~~~~~~~~~~~~~~~

0. Definitions.
^^^^^^^^^^^^^^^

"This License" refers to version 3 of the GNU General Public License.

"Copyright" also means copyright-like laws that apply to other kinds of
works, such as semiconductor masks.

"The Program" refers to any copyrightable work licensed under this
License. Each licensee is addressed as "you". "Licensees" and
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To "modify" a work means to copy from or adapt all or part of the work
in a fashion requiring copyright permission, other than the making of an
exact copy. The resulting work is called a "modified version" of the
earlier work or a work "based on" the earlier work.

A "covered work" means either the unmodified Program or a work based on
the Program.

To "propagate" a work means to do anything with it that, without
permission, would make you directly or secondarily liable for
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computer or modifying a private copy. Propagation includes copying,
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public, and in some countries other activities as well.

To "convey" a work means any kind of propagation that enables other
parties to make or receive copies. Mere interaction with a user through
a computer network, with no transfer of a copy, is not conveying.

An interactive user interface displays "Appropriate Legal Notices" to
the extent that it includes a convenient and prominently visible feature
that (1) displays an appropriate copyright notice, and (2) tells the
user that there is no warranty for the work (except to the extent that
warranties are provided), that licensees may convey the work under this
License, and how to view a copy of this License. If the interface
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item in the list meets this criterion.

1. Source Code.
^^^^^^^^^^^^^^^

The "source code" for a work means the preferred form of the work for
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2. Basic Permissions.
^^^^^^^^^^^^^^^^^^^^^

All rights granted under this License are granted for the term of
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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6. Conveying Non-Source Forms.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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part of a transaction in which the right of possession and use of the
User Product is transferred to the recipient in perpetuity or for a
fixed term (regardless of how the transaction is characterized), the
Corresponding Source conveyed under this section must be accompanied by
the Installation Information. But this requirement does not apply if
neither you nor any third party retains the ability to install modified
object code on the User Product (for example, the work has been
installed in ROM).

The requirement to provide Installation Information does not include a
requirement to continue to provide support service, warranty, or updates
for a work that has been modified or installed by the recipient, or for
the User Product in which it has been modified or installed. Access to a
network may be denied when the modification itself materially and
adversely affects the operation of the network or violates the rules and
protocols for communication across the network.

Corresponding Source conveyed, and Installation Information provided, in
accord with this section must be in a format that is publicly documented
(and with an implementation available to the public in source code
form), and must require no special password or key for unpacking,
reading or copying.

7. Additional Terms.
^^^^^^^^^^^^^^^^^^^^

"Additional permissions" are terms that supplement the terms of this
License by making exceptions from one or more of its conditions.
Additional permissions that are applicable to the entire Program shall
be treated as though they were included in this License, to the extent
that they are valid under applicable law. If additional permissions
apply only to part of the Program, that part may be used separately
under those permissions, but the entire Program remains governed by this
License without regard to the additional permissions.

When you convey a copy of a covered work, you may at your option remove
any additional permissions from that copy, or from any part of it.
(Additional permissions may be written to require their own removal in
certain cases when you modify the work.) You may place additional
permissions on material, added by you to a covered work, for which you
have or can give appropriate copyright permission.

Notwithstanding any other provision of this License, for material you
add to a covered work, you may (if authorized by the copyright holders
of that material) supplement the terms of this License with terms:

a) Disclaiming warranty or limiting liability differently from the
   terms of sections 15 and 16 of this License; or

b) Requiring preservation of specified reasonable legal notices or
   author attributions in that material or in the Appropriate Legal
   Notices displayed by works containing it; or

c) Prohibiting misrepresentation of the origin of that material, or
   requiring that modified versions of such material be marked in
   reasonable ways as different from the original version; or

d) Limiting the use for publicity purposes of names of licensors or
   authors of the material; or

e) Declining to grant rights under trademark law for use of some
   trade names, trademarks, or service marks; or

f) Requiring indemnification of licensors and authors of that
   material by anyone who conveys the material (or modified versions
   of it) with contractual assumptions of liability to the recipient,
   for any liability that these contractual assumptions directly
   impose on those licensors and authors.

All other non-permissive additional terms are considered "further
restrictions" within the meaning of section 10. If the Program as you
received it, or any part of it, contains a notice stating that it is
governed by this License along with a term that is a further
restriction, you may remove that term. If a license document contains a
further restriction but permits relicensing or conveying under this
License, you may add to a covered work material governed by the terms of
that license document, provided that the further restriction does not
survive such relicensing or conveying.

If you add terms to a covered work in accord with this section, you must
place, in the relevant source files, a statement of the additional terms
that apply to those files, or a notice indicating where to find the
applicable terms.

Additional terms, permissive or non-permissive, may be stated in the
form of a separately written license, or stated as exceptions; the above
requirements apply either way.

8. Termination.
^^^^^^^^^^^^^^^

You may not propagate or modify a covered work except as expressly
provided under this License. Any attempt otherwise to propagate or
modify it is void, and will automatically terminate your rights under
this License (including any patent licenses granted under the third
paragraph of section 11).

However, if you cease all violation of this License, then your license
from a particular copyright holder is reinstated (a) provisionally,
unless and until the copyright holder explicitly and finally terminates
your license, and (b) permanently, if the copyright holder fails to
notify you of the violation by some reasonable means prior to 60 days
after the cessation.

Moreover, your license from a particular copyright holder is reinstated
permanently if the copyright holder notifies you of the violation by
some reasonable means, this is the first time you have received notice
of violation of this License (for any work) from that copyright holder,
and you cure the violation prior to 30 days after your receipt of the
notice.

Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License. If your rights have been terminated and not permanently
reinstated, you do not qualify to receive new licenses for the same
material under section 10.

9. Acceptance Not Required for Having Copies.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

You are not required to accept this License in order to receive or run a
copy of the Program. Ancillary propagation of a covered work occurring
solely as a consequence of using peer-to-peer transmission to receive a
copy likewise does not require acceptance. However, nothing other than
this License grants you permission to propagate or modify any covered
work. These actions infringe copyright if you do not accept this
License. Therefore, by modifying or propagating a covered work, you
indicate your acceptance of this License to do so.

10. Automatic Licensing of Downstream Recipients.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Each time you convey a covered work, the recipient automatically
receives a license from the original licensors, to run, modify and
propagate that work, subject to this License. You are not responsible
for enforcing compliance by third parties with this License.

An "entity transaction" is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations. If propagation of a covered work
results from an entity transaction, each party to that transaction who
receives a copy of the work also receives whatever licenses to the work
the party's predecessor in interest had or could give under the previous
paragraph, plus a right to possession of the Corresponding Source of the
work from the predecessor in interest, if the predecessor has it or can
get it with reasonable efforts.

You may not impose any further restrictions on the exercise of the
rights granted or affirmed under this License. For example, you may not
impose a license fee, royalty, or other charge for exercise of rights
granted under this License, and you may not initiate litigation
(including a cross-claim or counterclaim in a lawsuit) alleging that any
patent claim is infringed by making, using, selling, offering for sale,
or importing the Program or any portion of it.

11. Patents.
^^^^^^^^^^^^

A "contributor" is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based. The work
thus licensed is called the contributor's "contributor version".

A contributor's "essential patent claims" are all patent claims owned or
controlled by the contributor, whether already acquired or hereafter
acquired, that would be infringed by some manner, permitted by this
License, of making, using, or selling its contributor version, but do
not include claims that would be infringed only as a consequence of
further modification of the contributor version. For purposes of this
definition, "control" includes the right to grant patent sublicenses in
a manner consistent with the requirements of this License.

Each contributor grants you a non-exclusive, worldwide, royalty-free
patent license under the contributor's essential patent claims, to make,
use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.

In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement). To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.

If you convey a covered work, knowingly relying on a patent license, and
the Corresponding Source of the work is not available for anyone to
copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients. "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.

If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify or
convey a specific copy of the covered work, then the patent license you
grant is automatically extended to all recipients of the covered work
and works based on it.

A patent license is "discriminatory" if it does not include within the
scope of its coverage, prohibits the exercise of, or is conditioned on
the non-exercise of one or more of the rights that are specifically
granted under this License. You may not convey a covered work if you are
a party to an arrangement with a third party that is in the business of
distributing software, under which you make payment to the third party
based on the extent of your activity of conveying the work, and under
which the third party grants, to any of the parties who would receive
the covered work from you, a discriminatory patent license (a) in
connection with copies of the covered work conveyed by you (or copies
made from those copies), or (b) primarily for and in connection with
specific products or compilations that contain the covered work, unless
you entered into that arrangement, or that patent license was granted,
prior to 28 March 2007.

Nothing in this License shall be construed as excluding or limiting any
implied license or other defenses to infringement that may otherwise be
available to you under applicable patent law.

12. No Surrender of Others' Freedom.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

If conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License. If you cannot convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you
may not convey it at all. For example, if you agree to terms that
obligate you to collect a royalty for further conveying from those to
whom you convey the Program, the only way you could satisfy both those
terms and this License would be to refrain entirely from conveying the
Program.

13. Use with the GNU Affero General Public License.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Notwithstanding any other provision of this License, you have permission
to link or combine any covered work with a work licensed under version 3
of the GNU Affero General Public License into a single combined work,
and to convey the resulting work. The terms of this License will
continue to apply to the part which is the covered work, but the special
requirements of the GNU Affero General Public License, section 13,
concerning interaction through a network will apply to the combination
as such.

14. Revised Versions of this License.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The Free Software Foundation may publish revised and/or new versions of
the GNU General Public License from time to time. Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.

Each version is given a distinguishing version number. If the Program
specifies that a certain numbered version of the GNU General Public
License "or any later version" applies to it, you have the option of
following the terms and conditions either of that numbered version or of
any later version published by the Free Software Foundation. If the
Program does not specify a version number of the GNU General Public
License, you may choose any version ever published by the Free Software
Foundation.

If the Program specifies that a proxy can decide which future versions
of the GNU General Public License can be used, that proxy's public
statement of acceptance of a version permanently authorizes you to
choose that version for the Program.

Later license versions may give you additional or different permissions.
However, no additional obligations are imposed on any author or
copyright holder as a result of your choosing to follow a later version.

15. Disclaimer of Warranty.
^^^^^^^^^^^^^^^^^^^^^^^^^^^

THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT
WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF
THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

16. Limitation of Liability.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR
CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT
NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES
SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE
WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

17. Interpretation of Sections 15 and 16.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

If the disclaimer of warranty and limitation of liability provided above
cannot be given local legal effect according to their terms, reviewing
courts shall apply local law that most closely approximates an absolute
waiver of all civil liability in connection with the Program, unless a
warranty or assumption of liability accompanies a copy of the Program in
return for a fee.

END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Programs
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these
terms.

To do so, attach the following notices to the program. It is safest to
attach them to the start of each source file to most effectively state
the exclusion of warranty; and each file should have at least the
"copyright" line and a pointer to where the full notice is found.

::

        <one line to give the program's name and a brief idea of what it does.>
        Copyright (C) <year>  <name of author>

        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 3 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, see <https://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

If the program does terminal interaction, make it output a short notice
like this when it starts in an interactive mode:

::

        <program>  Copyright (C) <year>  <name of author>
        This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
        This is free software, and you are welcome to redistribute it
        under certain conditions; type `show c' for details.

The hypothetical commands \`show w' and \`show c' should show the
appropriate parts of the General Public License. Of course, your
program's commands might be different; for a GUI interface, you would
use an "about box".

You should also get your employer (if you work as a programmer) or
school, if any, to sign a "copyright disclaimer" for the program, if
necessary. For more information on this, and how to apply and follow the
GNU GPL, see https://www.gnu.org/licenses/.

The GNU General Public License does not permit incorporating your
program into proprietary programs. If your program is a subroutine
library, you may consider it more useful to permit linking proprietary
applications with the library. If this is what you want to do, use the
GNU Lesser General Public License instead of this License. But first,
please read https://www.gnu.org/licenses/why-not-lgpl.html.""");

      about_dlg.response.connect (() => {
        about_dlg.hide ();
      });

      about_dlg.hide.connect (() => {
        about_dlg.destroy ();
        about_dlg = null;
      });

      about_dlg.show_all ();
    }

    /**
     * Displays the preferences dialog.
     *
     * @param controller the dock to show preferences for
     */
    void show_preferences (DockController controller) {
      if (preferences_dlg != null) {
        preferences_dlg.controller = controller;
        preferences_dlg.set_transient_for (controller.window);
        preferences_dlg.show ();
        return;
      }

      preferences_dlg = new PreferencesWindow (controller);
      preferences_dlg.set_transient_for (controller.window);

      preferences_dlg.destroy.connect (() => {
        preferences_dlg = null;
      });

      preferences_dlg.hide.connect (() => {
        preferences_dlg.destroy ();
        preferences_dlg = null;
      });

      preferences_dlg.show ();
    }
  }
}
