/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */

/* GIO - GLib Input, Output and Streaming Library

 * 

 * Copyright (C) 2006-2007 Red Hat, Inc.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General

 * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.

 *

 * Author: Alexander Larsson <alexl@redhat.com>

 *         David Zeuthen <davidz@redhat.com>

 */

#include "config.h"

#include <string.h>

#include <glib.h>

#include "gunionvolumemonitor.h"

#include "gmountprivate.h"

#include "giomodule-priv.h"

#ifdef G_OS_UNIX

#include "gunixvolumemonitor.h"

#endif

#include "gnativevolumemonitor.h"

#include "glibintl.h"

struct _GUnionVolumeMonitor {

  GVolumeMonitor parent;

  GList *monitors;

};

static void g_union_volume_monitor_remove_monitor (GUnionVolumeMonitor *union_monitor,

						   GVolumeMonitor *child_monitor);

#define g_union_volume_monitor_get_type _g_union_volume_monitor_get_type

G_DEFINE_TYPE (GUnionVolumeMonitor, g_union_volume_monitor, G_TYPE_VOLUME_MONITOR)

static GRecMutex the_volume_monitor_mutex;

static GUnionVolumeMonitor *the_volume_monitor = NULL;

static void

g_union_volume_monitor_finalize (GObject *object)

{

  GUnionVolumeMonitor *monitor;

  GVolumeMonitor *child_monitor;

  monitor = G_UNION_VOLUME_MONITOR (object);

  while (monitor->monitors != NULL)

    {

      child_monitor = monitor->monitors->data;

      g_union_volume_monitor_remove_monitor (monitor, 

                                             child_monitor);

      g_object_unref (child_monitor);

    }

  G_OBJECT_CLASS (g_union_volume_monitor_parent_class)->finalize (object);

}

static void

g_union_volume_monitor_dispose (GObject *object)

{

  GUnionVolumeMonitor *monitor;

  GVolumeMonitor *child_monitor;

  GList *l;

  monitor = G_UNION_VOLUME_MONITOR (object);

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  the_volume_monitor = NULL;

  for (l = monitor->monitors; l != NULL; l = l->next)

    {

      child_monitor = l->data;

      g_object_run_dispose (G_OBJECT (child_monitor));

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  G_OBJECT_CLASS (g_union_volume_monitor_parent_class)->dispose (object);

}

static GList *

get_mounts (GVolumeMonitor *volume_monitor)

{

  GUnionVolumeMonitor *monitor;

  GVolumeMonitor *child_monitor;

  GList *res;

  GList *l;

  monitor = G_UNION_VOLUME_MONITOR (volume_monitor);

  res = NULL;

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  for (l = monitor->monitors; l != NULL; l = l->next)

    {

      child_monitor = l->data;

      res = g_list_concat (res, g_volume_monitor_get_mounts (child_monitor));

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  return res;

}

static GList *

get_volumes (GVolumeMonitor *volume_monitor)

{

  GUnionVolumeMonitor *monitor;

  GVolumeMonitor *child_monitor;

  GList *res;

  GList *l;

  monitor = G_UNION_VOLUME_MONITOR (volume_monitor);

  res = NULL;

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  for (l = monitor->monitors; l != NULL; l = l->next)

    {

      child_monitor = l->data;

      res = g_list_concat (res, g_volume_monitor_get_volumes (child_monitor));

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  return res;

}

static GList *

get_connected_drives (GVolumeMonitor *volume_monitor)

{

  GUnionVolumeMonitor *monitor;

  GVolumeMonitor *child_monitor;

  GList *res;

  GList *l;

  monitor = G_UNION_VOLUME_MONITOR (volume_monitor);

  res = NULL;

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  for (l = monitor->monitors; l != NULL; l = l->next)

    {

      child_monitor = l->data;

      res = g_list_concat (res, g_volume_monitor_get_connected_drives (child_monitor));

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  return res;

}

static GVolume *

get_volume_for_uuid (GVolumeMonitor *volume_monitor, const char *uuid)

{

  GUnionVolumeMonitor *monitor;

  GVolumeMonitor *child_monitor;

  GVolume *volume;

  GList *l;

  monitor = G_UNION_VOLUME_MONITOR (volume_monitor);

  volume = NULL;

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  for (l = monitor->monitors; l != NULL; l = l->next)

    {

      child_monitor = l->data;

      volume = g_volume_monitor_get_volume_for_uuid (child_monitor, uuid);

      if (volume != NULL)

        break;

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  return volume;

}

static GMount *

get_mount_for_uuid (GVolumeMonitor *volume_monitor, const char *uuid)

{

  GUnionVolumeMonitor *monitor;

  GVolumeMonitor *child_monitor;

  GMount *mount;

  GList *l;

  monitor = G_UNION_VOLUME_MONITOR (volume_monitor);

  mount = NULL;

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  for (l = monitor->monitors; l != NULL; l = l->next)

    {

      child_monitor = l->data;

      mount = g_volume_monitor_get_mount_for_uuid (child_monitor, uuid);

      if (mount != NULL)

        break;

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  return mount;

}

static void

g_union_volume_monitor_class_init (GUnionVolumeMonitorClass *klass)

{

  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);

  GVolumeMonitorClass *monitor_class = G_VOLUME_MONITOR_CLASS (klass);

  gobject_class->finalize = g_union_volume_monitor_finalize;

  gobject_class->dispose = g_union_volume_monitor_dispose;

  monitor_class->get_connected_drives = get_connected_drives;

  monitor_class->get_volumes = get_volumes;

  monitor_class->get_mounts = get_mounts;

  monitor_class->get_volume_for_uuid = get_volume_for_uuid;

  monitor_class->get_mount_for_uuid = get_mount_for_uuid;

}

static void

child_volume_added (GVolumeMonitor      *child_monitor,

                    GVolume    *child_volume,

                    GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "volume-added",

			 child_volume);

}

static void

child_volume_removed (GVolumeMonitor      *child_monitor,

                      GVolume    *child_volume,

                      GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "volume-removed",

			 child_volume);

}

static void

child_volume_changed (GVolumeMonitor      *child_monitor,

                      GVolume    *child_volume,

                      GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "volume-changed",

			 child_volume);

}

static void

child_mount_added (GVolumeMonitor      *child_monitor,

                   GMount              *child_mount,

                   GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

                         "mount-added",

                         child_mount);

}

static void

child_mount_removed (GVolumeMonitor      *child_monitor,

                     GMount              *child_mount,

                     GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "mount-removed",

			 child_mount);

}

static void

child_mount_pre_unmount (GVolumeMonitor       *child_monitor,

                          GMount              *child_mount,

                          GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "mount-pre-unmount",

			 child_mount);

}

static void

child_mount_changed (GVolumeMonitor       *child_monitor,

                      GMount              *child_mount,

                      GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "mount-changed",

			 child_mount);

}

static void

child_drive_connected (GVolumeMonitor      *child_monitor,

                       GDrive              *child_drive,

                       GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "drive-connected",

			 child_drive);

}

static void

child_drive_disconnected (GVolumeMonitor      *child_monitor,

                          GDrive              *child_drive,

                          GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

			 "drive-disconnected",

			 child_drive);

}

static void

child_drive_changed (GVolumeMonitor      *child_monitor,

                     GDrive             *child_drive,

                     GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

                         "drive-changed",

                         child_drive);

}

static void

child_drive_eject_button (GVolumeMonitor      *child_monitor,

                          GDrive             *child_drive,

                          GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

                         "drive-eject-button",

                         child_drive);

}

static void

child_drive_stop_button (GVolumeMonitor      *child_monitor,

                         GDrive             *child_drive,

                         GUnionVolumeMonitor *union_monitor)

{

  g_signal_emit_by_name (union_monitor,

                         "drive-stop-button",

                         child_drive);

}

static void

g_union_volume_monitor_add_monitor (GUnionVolumeMonitor *union_monitor,

                                    GVolumeMonitor      *volume_monitor)

{

  if (g_list_find (union_monitor->monitors, volume_monitor))

    return;

  union_monitor->monitors =

    g_list_prepend (union_monitor->monitors,

		    g_object_ref (volume_monitor));

  g_signal_connect (volume_monitor, "volume-added", (GCallback)child_volume_added, union_monitor);

  g_signal_connect (volume_monitor, "volume-removed", (GCallback)child_volume_removed, union_monitor);

  g_signal_connect (volume_monitor, "volume-changed", (GCallback)child_volume_changed, union_monitor);

  g_signal_connect (volume_monitor, "mount-added", (GCallback)child_mount_added, union_monitor);

  g_signal_connect (volume_monitor, "mount-removed", (GCallback)child_mount_removed, union_monitor);

  g_signal_connect (volume_monitor, "mount-pre-unmount", (GCallback)child_mount_pre_unmount, union_monitor);

  g_signal_connect (volume_monitor, "mount-changed", (GCallback)child_mount_changed, union_monitor);

  g_signal_connect (volume_monitor, "drive-connected", (GCallback)child_drive_connected, union_monitor);

  g_signal_connect (volume_monitor, "drive-disconnected", (GCallback)child_drive_disconnected, union_monitor);

  g_signal_connect (volume_monitor, "drive-changed", (GCallback)child_drive_changed, union_monitor);

  g_signal_connect (volume_monitor, "drive-eject-button", (GCallback)child_drive_eject_button, union_monitor);

  g_signal_connect (volume_monitor, "drive-stop-button", (GCallback)child_drive_stop_button, union_monitor);

}

static void

g_union_volume_monitor_remove_monitor (GUnionVolumeMonitor *union_monitor,

                                       GVolumeMonitor      *child_monitor)

{

  GList *l;

  l = g_list_find (union_monitor->monitors, child_monitor);

  if (l == NULL)

    return;

  union_monitor->monitors = g_list_delete_link (union_monitor->monitors, l);

  g_signal_handlers_disconnect_by_func (child_monitor, child_volume_added, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_volume_removed, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_volume_changed, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_mount_added, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_mount_removed, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_mount_pre_unmount, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_mount_changed, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_drive_connected, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_drive_disconnected, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_drive_changed, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_drive_eject_button, union_monitor);

  g_signal_handlers_disconnect_by_func (child_monitor, child_drive_stop_button, union_monitor);

}

static GType

get_default_native_class (gpointer data)

{

  GNativeVolumeMonitorClass *klass, *native_class, **native_class_out;

  const char *use_this;

  GIOExtensionPoint *ep;

  GIOExtension *extension;

  GList *l;

  native_class_out = data;

  use_this = g_getenv ("GIO_USE_VOLUME_MONITOR");

  /* Ensure vfs in modules loaded */

  _g_io_modules_ensure_loaded ();

  ep = g_io_extension_point_lookup (G_NATIVE_VOLUME_MONITOR_EXTENSION_POINT_NAME);

  native_class = NULL;

  if (use_this)

    {

      extension = g_io_extension_point_get_extension_by_name (ep, use_this);

      if (extension)

	{

	  klass = G_NATIVE_VOLUME_MONITOR_CLASS (g_io_extension_ref_class (extension));

	  if (G_VOLUME_MONITOR_CLASS (klass)->is_supported())

	    native_class = klass;

	  else

	    g_type_class_unref (klass);

	}

    }

  if (native_class == NULL)

    {

      for (l = g_io_extension_point_get_extensions (ep); l != NULL; l = l->next)

	{

	  extension = l->data;

	  klass = G_NATIVE_VOLUME_MONITOR_CLASS (g_io_extension_ref_class (extension));

	  if (G_VOLUME_MONITOR_CLASS (klass)->is_supported())

	    {

	      native_class = klass;

	      break;

	    }

	  else

	    g_type_class_unref (klass);

	}

    }

  if (native_class)

    {

      *native_class_out = native_class;

      return G_TYPE_FROM_CLASS (native_class);

    }

  else

    return G_TYPE_INVALID;

}

/* We return the class, with a ref taken.

 * This way we avoid unloading the class/module

 * between selecting the type and creating the

 * instance on the first call.

 */

static GNativeVolumeMonitorClass *

get_native_class (void)

{

  static GOnce once_init = G_ONCE_INIT;

  GTypeClass *type_class;

  type_class = NULL;

  g_once (&once_init, (GThreadFunc)get_default_native_class, &type_class);

  if (type_class == NULL && once_init.retval != GUINT_TO_POINTER(G_TYPE_INVALID))

    type_class = g_type_class_ref ((GType)once_init.retval);

  return (GNativeVolumeMonitorClass *)type_class;

}

static void

g_union_volume_monitor_init (GUnionVolumeMonitor *union_monitor)

{

}

static void

populate_union_monitor (GUnionVolumeMonitor *union_monitor)

{

  GVolumeMonitor *monitor;

  GNativeVolumeMonitorClass *native_class;

  GVolumeMonitorClass *klass;

  GIOExtensionPoint *ep;

  GIOExtension *extension;

  GList *l;

  native_class = get_native_class ();

  if (native_class != NULL)

    {

      monitor = g_object_new (G_TYPE_FROM_CLASS (native_class), NULL);

      g_union_volume_monitor_add_monitor (union_monitor, monitor);

      g_object_unref (monitor);

      g_type_class_unref (native_class);

    }

  ep = g_io_extension_point_lookup (G_VOLUME_MONITOR_EXTENSION_POINT_NAME);

  for (l = g_io_extension_point_get_extensions (ep); l != NULL; l = l->next)

    {

      extension = l->data;

      klass = G_VOLUME_MONITOR_CLASS (g_io_extension_ref_class (extension));

      if (klass->is_supported == NULL || klass->is_supported())

	{

	  monitor = g_object_new (g_io_extension_get_type (extension), NULL);

	  g_union_volume_monitor_add_monitor (union_monitor, monitor);

	  g_object_unref (monitor);

	}

      g_type_class_unref (klass);

    }

}

static GUnionVolumeMonitor *

g_union_volume_monitor_new (void)

{

  GUnionVolumeMonitor *monitor;

  monitor = g_object_new (G_TYPE_UNION_VOLUME_MONITOR, NULL);

  return monitor;

}

/**

 * g_volume_monitor_get:

 * 

 * Gets the volume monitor used by gio.

 *

 * Returns: (transfer full): a reference to the #GVolumeMonitor used by gio. Call

 *    g_object_unref() when done with it.

 **/

GVolumeMonitor *

g_volume_monitor_get (void)

{

  GVolumeMonitor *vm;

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  if (the_volume_monitor)

    vm = G_VOLUME_MONITOR (g_object_ref (the_volume_monitor));

  else

    {

      the_volume_monitor = g_union_volume_monitor_new ();

      populate_union_monitor (the_volume_monitor);

      vm = G_VOLUME_MONITOR (the_volume_monitor);

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  return vm;

}

GMount *

_g_mount_get_for_mount_path (const gchar  *mount_path,

			     GCancellable *cancellable)

{

  GNativeVolumeMonitorClass *klass;

  GMount *mount;

  klass = get_native_class ();

  if (klass == NULL)

    return NULL;

  mount = NULL;

  if (klass->get_mount_for_mount_path)

    mount = klass->get_mount_for_mount_path (mount_path, cancellable);

  /* TODO: How do we know this succeeded? Keep in mind that the native

   *       volume monitor may fail (e.g. not being able to connect to

   *       hald). Is the get_mount_for_mount_path() method allowed to

   *       return NULL? Seems like it is ... probably the method needs

   *       to take a boolean and write if it succeeds or not.. Messy.

   *       Very messy.

   */

  g_type_class_unref (klass);

  return mount;

}

/**

 * g_volume_monitor_adopt_orphan_mount:

 * @mount: a #GMount object to find a parent for

 *

 * This function should be called by any #GVolumeMonitor

 * implementation when a new #GMount object is created that is not

 * associated with a #GVolume object. It must be called just before

 * emitting the @mount_added signal.

 *

 * If the return value is not %NULL, the caller must associate the

 * returned #GVolume object with the #GMount. This involves returning

 * it in its g_mount_get_volume() implementation. The caller must

 * also listen for the "removed" signal on the returned object

 * and give up its reference when handling that signal

 * 

 * Similary, if implementing g_volume_monitor_adopt_orphan_mount(),

 * the implementor must take a reference to @mount and return it in

 * its g_volume_get_mount() implemented. Also, the implementor must

 * listen for the "unmounted" signal on @mount and give up its

 * reference upon handling that signal.

 *

 * There are two main use cases for this function.

 *

 * One is when implementing a user space file system driver that reads

 * blocks of a block device that is already represented by the native

 * volume monitor (for example a CD Audio file system driver). Such

 * a driver will generate its own #GMount object that needs to be

 * associated with the #GVolume object that represents the volume.

 *

 * The other is for implementing a #GVolumeMonitor whose sole purpose

 * is to return #GVolume objects representing entries in the users

 * "favorite servers" list or similar.

 *

 * Returns: (transfer full): the #GVolume object that is the parent for @mount or %NULL

 * if no wants to adopt the #GMount.

 *

 * Deprecated: 2.20: Instead of using this function, #GVolumeMonitor

 * implementations should instead create shadow mounts with the URI of

 * the mount they intend to adopt. See the proxy volume monitor in

 * gvfs for an example of this. Also see g_mount_is_shadowed(),

 * g_mount_shadow() and g_mount_unshadow() functions.

 */

GVolume *

g_volume_monitor_adopt_orphan_mount (GMount *mount)

{

  GVolumeMonitor *child_monitor;

  GVolumeMonitorClass *child_monitor_class;

  GVolume *volume;

  GList *l;

  g_return_val_if_fail (mount != NULL, NULL);

  if (the_volume_monitor == NULL)

    return NULL;

  volume = NULL;

  g_rec_mutex_lock (&the_volume_monitor_mutex);

  for (l = the_volume_monitor->monitors; l != NULL; l = l->next)

    {

      child_monitor = l->data;

      child_monitor_class = G_VOLUME_MONITOR_GET_CLASS (child_monitor);

      if (child_monitor_class->adopt_orphan_mount != NULL)

        {

          volume = child_monitor_class->adopt_orphan_mount (mount, child_monitor);

          if (volume != NULL)

            break;

        }

    }

  g_rec_mutex_unlock (&the_volume_monitor_mutex);

  return volume;

}