/*

  * Copyright (C) 2014, 2016, 2018, 2020  J. Ali Harlow <ali@juiblex.co.uk>

  *

  * 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.

  */

 #include "config.h"

 #include <stdlib.h>

 #include <string.h>

 #include <errno.h>

 #include <gtk/gtk.h>

 #include <plover/plover.h>

 #include <plover/transaction.h>

 #include <plover-gtk/transactionhelper.h>

 #include "plover/uri-handler.h"

 /*

  * A PloverTransactionHelper uses a GtkAssistant to help a user run a

  * transaction.

  */

 G_DEFINE_TYPE(PloverTransactionHelper,plover_transaction_helper,G_TYPE_OBJECT)

 enum plover_transaction_type {

     TRANSACTION_TYPE_NULL=0,

     TRANSACTION_TYPE_INSTALL=1UL<<0,

     TRANSACTION_TYPE_REMOVE=1UL<<1,

     TRANSACTION_TYPE_UPDATE=TRANSACTION_TYPE_INSTALL|TRANSACTION_TYPE_REMOVE

 };

 typedef struct _PloverTransactionHelperPrivate {

     enum plover_transaction_type transaction_type;

     gchar *default_prefix;

 } PloverTransactionHelperPrivate;

 #define PLOVER_TRANSACTION_HELPER_GET_PRIVATE(obj)\

                                 G_TYPE_INSTANCE_GET_PRIVATE(obj,\

 				  PLOVER_TYPE_TRANSACTION_HELPER,\

 				  PloverTransactionHelperPrivate)

 enum {

     CLOSE=0,

     N_SIGNALS

 };

 static guint signals[N_SIGNALS];

 static PloverTransaction *

   plover_transaction_helper_new_transaction(PloverTransactionHelper *helper,

   GError **error);

 static void plover_transaction_helper_finalize(PloverTransactionHelper *helper)

 {

     PloverTransactionHelperPrivate *priv;

     priv=PLOVER_TRANSACTION_HELPER_GET_PRIVATE(helper);

     g_free(priv->default_prefix);

     g_free(helper->error_primary_text);

     g_free(helper->base);

     g_free(helper->base_uri);

     g_free(helper->unsatisfied);

     if (helper->comps)

 	plover_comps_free(helper->comps);

     plover_vector_free(helper->report_adding);

     plover_vector_free(helper->report_removing);

 }

 static void plover_transaction_helper_dispose(PloverTransactionHelper *helper)

 {

     g_clear_error(&helper->error);

     if (helper->error_dialog)

     {

 	g_signal_handlers_disconnect_by_data(helper->error_dialog,helper);

 	gtk_widget_destroy(helper->error_dialog);

 	helper->error_dialog=NULL;

     }

     if (helper->assistant)

     {

 	g_signal_handlers_disconnect_by_data(helper->assistant,helper);

 	g_clear_object(&helper->assistant);

     }

     g_clear_object(&helper->ui);

     g_slist_foreach(helper->transactions,(GFunc)g_object_unref,NULL);

     g_slist_free(helper->transactions);

     helper->transactions=NULL;

     g_clear_object(&helper->alternate_installed);

     g_clear_object(&helper->installed);

     g_clear_object(&helper->upstream);

     g_clear_object(&helper->relocated_upstream);

 }

 static void

   plover_transaction_helper_class_init(PloverTransactionHelperClass *klass)

 {

     GObjectClass *gobject_class=G_OBJECT_CLASS(klass);

     gobject_class->finalize=

       (void (*)(GObject *))plover_transaction_helper_finalize;

     gobject_class->dispose=

       (void (*)(GObject *))plover_transaction_helper_dispose;

     g_type_class_add_private(klass,sizeof(PloverTransactionHelperPrivate));

     signals[CLOSE]=g_signal_newv("close",

       G_TYPE_FROM_CLASS(klass),G_SIGNAL_RUN_LAST,NULL,NULL,NULL,

       g_cclosure_marshal_VOID__VOID,G_TYPE_NONE,0,NULL);

 }

 static void plover_transaction_helper_init(PloverTransactionHelper *helper)

 {

     helper->report_adding=plover_vector_new();

     helper->report_removing=plover_vector_new();

 }

 static void plover_transaction_helper_assistant_cancel(GtkAssistant *assistant,

   PloverTransactionHelper *helper)

 {

     gtk_widget_hide(GTK_WIDGET(helper->assistant));

     gtk_assistant_set_current_page(helper->assistant,0);

     g_signal_emit(helper,signals[CLOSE],0);

 }

 static void plover_transaction_helper_assistant_close(GtkAssistant *assistant,

   PloverTransactionHelper *helper)

 {

     gtk_widget_hide(GTK_WIDGET(helper->assistant));

     gtk_assistant_set_current_page(helper->assistant,0);

     g_signal_emit(helper,signals[CLOSE],0);

 }

 static void

   plover_transaction_helper_prepare_confirm(PloverTransactionHelper *helper)

 {

     gchar *package_list,*add,*remove,*s;

     GtkLabel *label;

     struct plover_vector *report;

     if (helper->report_adding->len)

     {

 	plover_vector_sort(helper->report_adding);

 	if (helper->report_adding_dependencies)

 	{

 	    report=plover_vector_dup(helper->report_adding);

 	    if (helper->report_adding->len==1)

 		plover_vector_append(report,"its dependencies");

 	    else

 		plover_vector_append(report,"their dependencies");

 	    package_list=plover_vector_format_for_display(report);

 	    plover_vector_free(report);

 	}

 	else

 	    package_list=

 	      plover_vector_format_for_display(helper->report_adding);

 	add=g_strconcat("Packages to be installed or updated: ",package_list,

 	  ".",NULL);

 	g_free(package_list);

     }

     else

 	add=NULL;

     if (helper->report_removing->len)

     {

 	plover_vector_sort(helper->report_removing);

 	if (helper->report_removing_dependants)

 	{

 	    report=plover_vector_dup(helper->report_removing);

 	    if (helper->report_adding->len==1)

 		plover_vector_append(report,"its dependants");

 	    else

 		plover_vector_append(report,"their dependants");

 	    package_list=plover_vector_format_for_display(report);

 	    plover_vector_free(report);

 	}

 	else

 	    package_list=

 	      plover_vector_format_for_display(helper->report_removing);

 	remove=g_strconcat("Packages to be removed: ",package_list,".",NULL);

 	g_free(package_list);

     }

     else

 	remove=NULL;

     label=GTK_LABEL(gtk_builder_get_object(helper->ui,"SISummaryOfWork"));

     if (add && remove)

 	s=g_strconcat("<b>Installation Summary</b>\n\n",remove,"\n\n",add,NULL);

     else if (add || remove)

 	s=g_strconcat("<b>Installation Summary</b>\n\n",add?add:remove,NULL);

     else

 	s=g_strdup("<b>Installation Summary</b>\n\nNo changes scheduled");

     gtk_label_set_markup(label,s);

     g_free(s);

     g_free(add);

     g_free(remove);

 }

 static void plover_transaction_helper_run(PloverTransactionHelper *helper);

 static void plover_transaction_helper_callback(GObject *source,

   GAsyncResult *result,gpointer user_data)

 {

     GError *error=NULL;

     PloverTransactionHelper *helper=user_data;

     PloverTransaction *transaction=PLOVER_TRANSACTION(source);

     if (!plover_transaction_commit_finish(transaction,result,&error))

     {

 	plover_transaction_helper_set_error(helper,error,

 	  "Software installation failed");

 	g_error_free(error);

     }

     else

 	plover_transaction_helper_run(helper);

     /*

      * There may be status updates queued by transaction as idle events.

      * Process them now before we disconnect so that we don't lose them.

      */

     while(g_main_context_pending(NULL))

 	g_main_context_iteration(NULL,FALSE);

     g_signal_handlers_disconnect_by_data(transaction,helper);

     g_object_unref(transaction);

 }

 static void plover_transaction_helper_transaction_status_changed(

   PloverTransaction *transaction,const char *status,

   PloverTransactionHelper *helper)

 {

     GtkProgressBar *bar;

     bar=GTK_PROGRESS_BAR(gtk_builder_get_object(helper->ui,"SIProgressBar"));

     gtk_progress_bar_set_text(bar,status);

 }

 static void plover_transaction_helper_run(PloverTransactionHelper *helper)

 {

     PloverTransaction *transaction;

     GtkWidget *page;

     page=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIProgress"));

     if (helper->transactions)

     {

 	if (helper->assistant)

 	    gtk_assistant_set_page_complete(helper->assistant,page,FALSE);

 	transaction=helper->transactions->data;

 	helper->transactions=g_slist_delete_link(helper->transactions,

 	  helper->transactions);

 	g_signal_connect(transaction,"status-changed",

 	  G_CALLBACK(plover_transaction_helper_transaction_status_changed),

 	  helper);

 	plover_transaction_commit_async(transaction,NULL,

 	  plover_transaction_helper_callback,helper);

     }

     else if (helper->assistant)

 	gtk_assistant_set_page_complete(helper->assistant,page,TRUE);

 }

 static gboolean plover_transaction_helper_pulse(gpointer user_data)

 {

     PloverTransactionHelper *helper=user_data;

     GtkWidget *w;

     GtkProgressBar *bar;

     if (!helper->assistant)

 	return FALSE;

     w=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIProgress"));

     bar=GTK_PROGRESS_BAR(gtk_builder_get_object(helper->ui,"SIProgressBar"));

     if (gtk_assistant_get_page_complete(helper->assistant,w))

     {

 	gtk_progress_bar_set_fraction(bar,1.0);

 	helper->pulse_handler=0;

 	return FALSE;

     }

     else

     {

 	gtk_progress_bar_pulse(bar);

 	return TRUE;

     }

 }

 static void

   plover_transaction_helper_prepare_progress(PloverTransactionHelper *helper)

 {

     GError *error=NULL;

     GtkToggleButton *button;

     PloverTransaction *transaction;

     GSList *save_transactions;

     PloverTransactionHelperPrivate *priv;

     enum plover_transaction_type save_transaction_type;

     priv=PLOVER_TRANSACTION_HELPER_GET_PRIVATE(helper);

     button=GTK_TOGGLE_BUTTON(gtk_builder_get_object(helper->ui,

       "SIRemoveExisting"));

     if (gtk_toggle_button_get_active(button))

     {

 	transaction=plover_transaction_helper_new_transaction(helper,&error);

 	/*

 	 * I think we want switch to the alternate installed set in the case of

 	 * alternate_database_clashes, but not in the case of

 	 * active_database_is_incompatible (see

 	 * plover_transaction_helper_update_summary_page).

 	 * Whether testing for helper->alternate_installed is sufficient I'm

 	 * far from clear.

 	 */

 	if (helper->alternate_installed)

 	    plover_transaction_set_installed(transaction,

 	      helper->alternate_installed);

 	if (transaction && !plover_transaction_remove(transaction,NULL,&error))

 	{

 	    g_object_unref(transaction);

 	    transaction=NULL;

 	}

 	if (transaction)

 	{

 	    save_transactions=helper->transactions;

 	    helper->transactions=NULL;

 	    save_transaction_type=priv->transaction_type;

 	    priv->transaction_type=0;

 	    if (!plover_transaction_helper_add_transaction(helper,transaction,

 	      NULL,PLOVER_TRANSACTION_HELPER_REPORT_REMOVE,&error))

 	    {

 		g_object_unref(transaction);

 		transaction=NULL;

 		helper->transactions=save_transactions;

 		priv->transaction_type=save_transaction_type;

 	    }

 	    else

 	    {

 		g_slist_foreach(save_transactions,(GFunc)g_object_unref,NULL);

 		g_slist_free(save_transactions);

 	    }

 	}

 	if (!transaction)

 	{

 	    if (g_error_matches(error,PLOVER_POSIX_ERROR,ENOENT))

 		g_clear_error(&error);

 	    if (error)

 	    {

 		plover_transaction_helper_set_error(helper,error,

 		  "Failed to remove existing packages");

 		g_error_free(error);

 		return;

 	    }

 	}

     }

     /*

      * Note that PloverTransaction does support cancelling a transaction, but

      * there are a number of challenges with using it:

      *	- cancellation is only supported during the file phase if razor

      *	  has atomic rollback,

      *  - cancellation is not supported during post-transaction scripts at all

      *    (since by the time the first script is started the atomic has already

      *    been committed) and these can take quite some time,

      *  - where a transaction has an embedded COMMIT, any rollback won't

      *    go back beyond this point.

      * To support user-cancel, then, we would need some mechanism to:

      *  - Comunicate that the operation is being cancelled and this may take

      *    some time,

      *  - Not allow cancellation at all after the last post-transaction script

      *    phase is started,

      *  - Report the partially completed transaction where cancellation

      *    occurred after a COMMIT point.

      * At present, this doesn't appear worth the effort.

      */

     if (helper->assistant)

 	gtk_assistant_commit(helper->assistant);

     plover_transaction_helper_run(helper);

     helper->pulse_handler=g_timeout_add(100,plover_transaction_helper_pulse,

       helper);

 }

 static void plover_transaction_helper_assistant_prepare(GtkAssistant *assistant,

   GtkWidget *page,PloverTransactionHelper *helper)

 {

     if (page==GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIConfirm")))

 	plover_transaction_helper_prepare_confirm(helper);

     else if (page==GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIProgress")))

 	plover_transaction_helper_prepare_progress(helper);

 }

 static void

   plover_transaction_helper_remove_existing_toggled(GtkToggleButton *button,

   PloverTransactionHelper *helper)

 {

     GtkWidget *w;

     if (helper->assistant)

     {

 	w=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIConfirm"));

 	gtk_assistant_set_page_complete(helper->assistant,w,

 	  gtk_toggle_button_get_active(button));

     }

 }

 PloverTransactionHelper *plover_transaction_helper_new(GtkBuilder *ui)

 {

     gsize len;

     gchar *s,*directory,*contents;

     GError *error=NULL;

     GtkWidget *w;

     PloverTransactionHelper *helper;

     g_return_val_if_fail(ui == NULL || GTK_IS_BUILDER(ui),NULL);

     helper=PLOVER_TRANSACTION_HELPER(

       g_object_new(PLOVER_TYPE_TRANSACTION_HELPER,NULL));

     if (ui)

 	helper->ui=g_object_ref(ui);

     else

 	helper->ui=gtk_builder_new();

     helper->assistant=

       GTK_ASSISTANT(gtk_builder_get_object(helper->ui,"SoftwareInstallation"));

     if (!helper->assistant)

     {

 	directory=g_strdup(g_getenv("PLOVER_DATADIR"));

 	if (!directory)

 	{

 #ifdef WIN32

 	    s=g_win32_get_package_installation_directory_of_module(NULL);

 	    directory=g_build_filename(s,"share","plover",NULL);

 	    g_free(s);

 #else

 	    directory=g_strdup(PLOVER_DATADIR);

 #endif

 	}

 	s=g_build_filename(directory,"software-installation.ui",NULL);

 	g_free(directory);

 	(void)g_file_get_contents(s,&contents,&len,&error);

 	g_free(s);

 	if (!error)

 	{

 	    (void)gtk_builder_add_from_string(helper->ui,contents,len,&error);

 	    g_free(contents);

 	}

 	if (error)

 	{

 	    g_critical("software-installation.ui: %s",error->message);

 	    g_clear_error(&error);

 	    g_set_error(&error,PLOVER_GENERAL_ERROR,PLOVER_GENERAL_ERROR_FAILED,

 	      "Internal error (no user interface)");

 	    plover_transaction_helper_set_error(helper,error,

 	      "Can't start installer");

 	    return helper;

 	}

 	helper->assistant=GTK_ASSISTANT(gtk_builder_get_object(helper->ui,

 	  "SoftwareInstallation"));

     }

     if (!helper->assistant)

     {

 	g_critical("\"SoftwareInstallation\" object not found");

 	g_set_error(&error,PLOVER_GENERAL_ERROR,PLOVER_GENERAL_ERROR_FAILED,

 	  "Internal error (missing wizard)");

 	plover_transaction_helper_set_error(helper,error,

 	  "Can't start installer");

 	g_error_free(error);

 	return helper;

     }

     else

 	g_object_ref(helper->assistant);

     if (!GTK_IS_ASSISTANT(helper->assistant))

     {

 	g_critical("\"SoftwareInstallation\" is not a GtkAssistant");

 	g_set_error(&error,PLOVER_GENERAL_ERROR,PLOVER_GENERAL_ERROR_FAILED,

 	  "Internal error (unexpected wizard type)");

 	plover_transaction_helper_set_error(helper,error,

 	  "Can't start installer");

 	g_error_free(error);

 	return helper;

     }

     g_signal_connect(helper->assistant,"cancel",

       G_CALLBACK(plover_transaction_helper_assistant_cancel),helper);

     g_signal_connect(helper->assistant,"close",

       G_CALLBACK(plover_transaction_helper_assistant_close),helper);

     g_signal_connect(helper->assistant,"prepare",

       G_CALLBACK(plover_transaction_helper_assistant_prepare),helper);

     w=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIRemoveExisting"));

     if (w)

 	g_signal_connect(w,"toggled",

 	  G_CALLBACK(plover_transaction_helper_remove_existing_toggled),helper);

     w=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIIntroduction"));

     if (w)

 	gtk_assistant_set_page_complete(helper->assistant,w,TRUE);

     return helper;

 }

 PloverPackageSet *

   plover_transaction_helper_get_installed(PloverTransactionHelper *helper)

 {

     gchar *s,*saved_database_uri;

     char *install_root,*local_database;

     char *active_database=NULL,*alternate_database=NULL;

     const char *prefix;

     struct comps *comps;

     PloverPackageSet *alternate_installed,*installed;

     GError *error=NULL;

     struct razor_error *razor_error=NULL;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     if (!helper->installed)

     {

 	comps=plover_transaction_helper_get_comps(helper,&error);

 	if (!comps)

 	{

 	    g_warning("plover_transaction_helper_get_installed: No comps: %s",

 	      error->message);

 	    g_error_free(error);

 	    return NULL;

 	}

 	install_root=getenv("RAZOR_ROOT");

 	if (!install_root)

 	    install_root="file:/";

 	prefix=plover_transaction_helper_get_prefix(helper,NULL);

 	if (prefix)

 	{

 	    s=g_strconcat(prefix,"/var/lib/razor",NULL);

 	    local_database=razor_path_relative_to_uri(install_root,*s=='/'?s+1:s,

 	      &razor_error);

 	    g_free(s);

 	    if (!local_database)

 	    {

 		g_warning("plover_transaction_helper_get_installed: %s",

 		  razor_error_get_msg(razor_error));

 		razor_error_free(razor_error);

 		return NULL;

 	    }

 	}

 	else

 	    local_database=NULL;

 	switch(comps->database)

 	{

 	    case COMPS_DATABASE_DISTRIBUTION_LOCAL:

 		active_database=local_database;

 		break;

 	    case COMPS_DATABASE_GLOBAL:

 		alternate_database=local_database;

 		break;

 	}

 	saved_database_uri=g_strdup(razor_get_database_uri());

 	if (prefix)

 	{

 	    razor_set_database_uri(alternate_database);

 	    alternate_installed=plover_package_set_new();

 	    if (!plover_package_set_open(alternate_installed,install_root,TRUE,

 	      &error))

 	    {

 		g_object_unref(alternate_installed);

 		g_warning("plover_transaction_helper_get_installed: %s",

 		  error->message);

 		g_error_free(error);

 		free(local_database);

 		razor_set_database_uri(saved_database_uri);

 		g_free(saved_database_uri);

 		return NULL;

 	    }

 	}

 	else

 	    alternate_installed=NULL;

 	razor_set_database_uri(active_database);

 	free(local_database);

 	installed=plover_package_set_new();

 	if (plover_package_set_open(installed,install_root,TRUE,&error))

 	{

 	    helper->alternate_installed=alternate_installed;

 	    helper->installed=installed;

 	}

 	else

 	{

 	    g_object_unref(installed);

 	    if (alternate_installed)

 		g_object_unref(alternate_installed);

 	    g_warning("plover_transaction_helper_get_installed: %s",error->message);

 	    g_error_free(error);

 	}

 	razor_set_database_uri(saved_database_uri);

 	g_free(saved_database_uri);

     }

     return helper->installed;

 }

 void plover_transaction_helper_set_installed(PloverTransactionHelper *helper,

   PloverPackageSet *installed)

 {

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     g_return_if_fail(PLOVER_IS_PACKAGE_SET(installed));

     g_return_if_fail(helper->installed == NULL);

     g_clear_object(&helper->alternate_installed);

     helper->installed=g_object_ref(installed);

 }

 PloverRepository *

   plover_transaction_helper_get_upstream(PloverTransactionHelper *helper,

   GError **error)

 {

     const char *base_uri;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     if (!helper->upstream)

     {

 	base_uri=plover_transaction_helper_get_base_uri(helper);

 	helper->upstream=plover_repository_new_from_yum_uri(base_uri,error);

     }

     return helper->upstream;

 }

 void plover_transaction_helper_set_upstream(PloverTransactionHelper *helper,

   PloverRepository *upstream)

 {

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     g_return_if_fail(PLOVER_IS_REPOSITORY(upstream));

     g_return_if_fail(helper->upstream == NULL);

     helper->upstream=g_object_ref(upstream);

 }

 const char *

   plover_transaction_helper_get_base_uri(PloverTransactionHelper *helper)

 {

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     return helper->base_uri;

 }

 static gboolean plover_gtk__uri_validate(const char *uri)

 {

     char *s;

     s=razor_path_relative_to_uri(uri,".",NULL);

     free(s);

     return !!s;

 }

 void plover_transaction_helper_set_base_uri(PloverTransactionHelper *helper,

   const char *base_uri)

 {

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     g_return_if_fail(helper->transactions == NULL);

     g_return_if_fail(plover_gtk__uri_validate(base_uri));

     g_free(helper->base_uri);

     helper->base_uri=g_strdup(base_uri);

     g_free(helper->base);

     helper->base=NULL;

 }

 const char *plover_transaction_helper_get_base(PloverTransactionHelper *helper)

 {

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     if (helper->base_uri && !helper->base)

 	helper->base=razor_path_from_uri(helper->base_uri,NULL);

     return helper->base;

 }

 void plover_transaction_helper_set_base(PloverTransactionHelper *helper,

   const char *base)

 {

     gchar *base_uri;

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     g_return_if_fail(helper->transactions == NULL);

     if (base)

 	base_uri=razor_path_to_uri(base);

     else

 	base_uri=NULL;

     plover_transaction_helper_set_base_uri(helper,base_uri);

     g_free(base_uri);

     helper->base=g_strdup(base);

 }

 struct comps *

   plover_transaction_helper_get_comps(PloverTransactionHelper *helper,

   GError **error)

 {

     char *s;

     GError *tmp_err=NULL;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     if (!helper->comps && helper->base_uri)

     {

 	s=razor_path_relative_to_uri(helper->base_uri,"repodata/comps.xml",

 	  NULL);

 	helper->comps=plover_comps_new_from_uri(s,&tmp_err);

 	if (!helper->comps)

 	{

 	    g_warning(

 	      "PloverTransactionHelper: Failed to get comps at '%s': %s",

 	      s,tmp_err->message);

 	    g_propagate_error(error,tmp_err);

 	}

 	free(s);

     }

     return helper->comps;

 }

 const char *

   plover_transaction_helper_get_prefix(PloverTransactionHelper *helper,

   GError **error)

 {

     const char *prefix;

     struct comps *comps;

     PloverTransactionHelperPrivate *priv;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     g_return_val_if_fail(helper->base_uri != NULL || plover_transaction_helper_get_installed(helper) != NULL,NULL);

     priv=PLOVER_TRANSACTION_HELPER_GET_PRIVATE(helper);

     if (helper->base_uri)

     {

 	comps=plover_transaction_helper_get_comps(helper,error);

 	if (!comps)

 	    return NULL;

 	g_free(priv->default_prefix);

 	priv->default_prefix=plover_comps_get_default_prefix(comps);

 	return priv->default_prefix;

     }

     prefix=plover_package_set_guess_prefix(helper->installed,error);

     return prefix;

 }

 #if 0

 static int plover_transaction_helper_package_count(void)

 {

     int count=0;

     char *install_root;

     struct razor_set *set;

     struct razor_package *package;

     struct razor_package_iterator *pi;

     install_root=getenv("RAZOR_ROOT");

     if (!install_root)

 	install_root="";

     set=razor_root_open_read_only(install_root,NULL);

     if (set)

     {

 	pi=razor_package_iterator_create(set);

 	while (razor_package_iterator_next(pi,&package,RAZOR_DETAIL_LAST))

 	    count++;

 	razor_package_iterator_destroy(pi);

 	razor_set_unref(set);

     }

     return count;

 }

 #endif

 static gboolean prefix_clashes(const char *prefix,const char *alt)

 {

     return g_str_has_prefix(prefix,alt) &&

       (prefix[strlen(alt)]=='\0' || prefix[strlen(alt)]=='/');

 }

 static void

   plover_transaction_helper_update_summary_page(PloverTransactionHelper *helper,

   GError **error)

 {

     int remove_count=0;

     gboolean alternate_database_clashes=FALSE;

     gboolean active_database_is_incompatible=FALSE;

     const char *alternate_prefix;

     gchar *prefix=NULL,*s;

     struct comps *comps=NULL;

     GtkWidget *container,*summary,*page;

     GtkButton *button;

     GtkLabel *label;

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     comps=plover_transaction_helper_get_comps(helper,error);

     if (comps)

 	prefix=plover_comps_get_default_prefix(comps);

     else

 	prefix=NULL;

     button=GTK_BUTTON(gtk_builder_get_object(helper->ui,"SIRemoveExisting"));

     gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(button),FALSE);

     container=GTK_WIDGET(gtk_builder_get_object(helper->ui,

       "SIIncompatibleInstallation"));

     summary=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SISummaryOfWork"));

     page=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIConfirm"));

     if (helper->check_vendor && prefix && helper->alternate_installed)

     {

 	alternate_prefix=

 	  plover_package_set_guess_prefix(helper->alternate_installed,NULL);

 	if (alternate_prefix && prefix_clashes(prefix,alternate_prefix))

 	{

 	    alternate_database_clashes=TRUE;

 	    remove_count=g_slist_length(

 	      plover_package_set_get_packages(helper->alternate_installed));

 	}

     }

     /*

      * Rather than try to be too clever, we only deal with one thing

      * at a time. That means that if the alternate database clashes

      * there's no point checking if the active database is compatible.

      */

     if (!alternate_database_clashes)

     {

 	if (helper->check_vendor && prefix &&

 	  !plover_package_set_files_match_prefix(helper->installed,prefix))

 	{

 	    active_database_is_incompatible=TRUE;

 	    remove_count=

 	      g_slist_length(plover_package_set_get_packages(helper->installed));

 	}

     }

     if (alternate_database_clashes || active_database_is_incompatible)

     {

 	g_assert(comps!=NULL);

 	label=GTK_LABEL(gtk_builder_get_object(helper->ui,

 	  "SIIncompatibleInstallationLabel"));

 	if (alternate_database_clashes)

 	    s=g_strdup_printf("<b>Incompatible Installation</b>\n\n"

 	      "There is an existing installation under %s\n"

 	      "which is not compatible with this distribution. In order\n"

 	      "to continue, the existing installation must be uninstalled.",

 	      comps->vendor);

 	else /* active_database_is_incompatible */

 	    s=g_strdup_printf("<b>Incompatible Installation</b>\n\n"

 	      "The existing installation is not from %s.\n In order "

 	      "to continue, all the existing packages must be removed.",

 	      comps->vendor);

 	gtk_label_set_markup(label,s);

 	g_free(s);

 	s=g_strdup_printf("Remove %d existing package%s",remove_count,

 	  remove_count==1?"":"s");

 	gtk_button_set_label(button,s);

 	g_free(s);

 	gtk_widget_show(container);

 	gtk_widget_hide(summary);

 	if (helper->assistant)

 	    gtk_assistant_set_page_complete(helper->assistant,page,FALSE);

     }

     else

     {

 	gtk_widget_hide(container);

 	gtk_widget_show(summary);

 	if (helper->assistant)

 	    gtk_assistant_set_page_complete(helper->assistant,page,TRUE);

     }

     g_free(prefix);

 }

 void plover_transaction_helper_set_check_vendor(PloverTransactionHelper *helper,

   gboolean check_vendor)

 {

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     if (helper->check_vendor!=check_vendor)

     {

 	helper->check_vendor=check_vendor;

 	if (helper->transactions)

 	    plover_transaction_helper_update_summary_page(helper,NULL);

     }

 }

 /*

  * If plover_transaction_helper_add_transaction() fails with an error

  * of PLOVER_GENERAL_ERROR,PLOVER_GENERAL_ERROR_REQUIREMENTS_NOT_MET

  * then plover_transaction_helper_get_unsatisfied() can be used to

  * retrieve a textual description of the problem.

  */

 const char *

   plover_transaction_helper_get_unsatisfied(PloverTransactionHelper *helper)

 {

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     return helper->unsatisfied;

 }

 #define PLOVER_TRANSACTION_HELPER_IS_VALID_REPORT_ACTION(action) \

   ((action)==PLOVER_TRANSACTION_HELPER_REPORT_INSTALL || \

   (action)==PLOVER_TRANSACTION_HELPER_REPORT_REMOVE || \

   (action)==PLOVER_TRANSACTION_HELPER_REPORT_UPDATE)

 gboolean

   plover_transaction_helper_add_transaction(PloverTransactionHelper *helper,

   PloverTransaction *transaction,struct plover_vector *report_packages,

   PloverTransactionHelperReportAction report_action,GError **error)

 {

     int i,count;

     gboolean other_packages;

     const char *s,*name;

     enum razor_install_action razor_action;

     PloverTransactionHelperReportAction action;

     struct razor_install_iterator *ii;

     struct razor_set *report_set;

     struct razor_package *package;

     struct plover_vector *tasked_packages;

     PloverTransactionHelperPrivate *priv;

     GtkWidget *w;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     g_return_val_if_fail(PLOVER_IS_TRANSACTION(transaction),FALSE);

     g_return_val_if_fail(PLOVER_TRANSACTION_HELPER_IS_VALID_REPORT_ACTION(report_action),FALSE);

     g_return_val_if_fail(plover_transaction_get_system_set(transaction)!=NULL,FALSE);

     priv=PLOVER_TRANSACTION_HELPER_GET_PRIVATE(helper);

     g_free(helper->unsatisfied);

     helper->unsatisfied=NULL;

     if (!plover_transaction_resolve(transaction,error))

     {

 	s=plover_transaction_get_unsatisfied(transaction);

 	helper->unsatisfied=g_strdup(s);

 	return FALSE;

     }

     ii=plover_transaction_get_install_iterator(transaction,error);

     if (!ii)

 	return FALSE;

     if (report_action==PLOVER_TRANSACTION_HELPER_REPORT_REMOVE)

 	report_set=plover_transaction_get_system_set(transaction);

     else

 	report_set=plover_transaction_get_next_set(transaction,error);

     if (!report_set)

 	return FALSE;

     tasked_packages=plover_vector_new();

     other_packages=FALSE;

     while (razor_install_iterator_next(ii,&package,&razor_action,&count))

     {

 	if (razor_action==RAZOR_INSTALL_ACTION_ADD)

 	    action=PLOVER_TRANSACTION_HELPER_REPORT_INSTALL;

 	else if (razor_action==RAZOR_INSTALL_ACTION_REMOVE)

 	    action=PLOVER_TRANSACTION_HELPER_REPORT_REMOVE;

 	else

 	    continue;

 	if (action==report_action || razor_action==RAZOR_INSTALL_ACTION_ADD &&

 	  report_action==PLOVER_TRANSACTION_HELPER_REPORT_UPDATE)

 	{

 	    razor_package_get_details(report_set,package,RAZOR_DETAIL_NAME,

 	      &name,RAZOR_DETAIL_LAST);

 	    if (!report_packages ||

 	      plover_vector_contains(report_packages,name))

 		plover_vector_append(tasked_packages,name);

 	    else

 		other_packages=TRUE;

 	}

     }

     if (!tasked_packages->len)

     {

 	/*

 	 * If there are no reportable packages tasked for action there

 	 * shouldn't be any packages at all, but let's be paranoid.

 	 */

 	other_packages=FALSE;

 	razor_install_iterator_rewind(ii);

 	while (razor_install_iterator_next(ii,&package,&razor_action,&count))

 	{

 	    if (razor_action==RAZOR_INSTALL_ACTION_ADD)

 		action=PLOVER_TRANSACTION_HELPER_REPORT_INSTALL;

 	    else if (razor_action==RAZOR_INSTALL_ACTION_REMOVE)

 		action=PLOVER_TRANSACTION_HELPER_REPORT_REMOVE;

 	    else

 		continue;

 	    if (action==report_action ||

 	      razor_action==RAZOR_INSTALL_ACTION_ADD &&

 	      report_action==PLOVER_TRANSACTION_HELPER_REPORT_UPDATE)

 	    {

 		razor_package_get_details(report_set,package,RAZOR_DETAIL_NAME,

 		  &name,RAZOR_DETAIL_LAST);

 		plover_vector_append(tasked_packages,name);

 	    }

 	}

     }

     if (!tasked_packages->len)

     {

 	g_set_error(error,PLOVER_GENERAL_ERROR,

 	  PLOVER_GENERAL_ERROR_NO_WORK,"Transaction includes no %s actions",

 	  report_action==PLOVER_TRANSACTION_HELPER_REPORT_REMOVE?

 	  "remove":"add");

 	plover_vector_free(tasked_packages);

 	return FALSE;

     }

     if (!helper->transactions)

 	plover_transaction_helper_update_summary_page(helper,error);

     g_object_ref(transaction);

     helper->transactions=g_slist_append(helper->transactions,transaction);

     if (report_action==PLOVER_TRANSACTION_HELPER_REPORT_REMOVE)

     {

 	priv->transaction_type|=TRANSACTION_TYPE_REMOVE;

 	for(i=0;i<tasked_packages->len;i++)

 	{

 	    s=tasked_packages->strings[i];

 	    if (!plover_vector_contains(helper->report_removing,s))

 		plover_vector_append(helper->report_removing,s);

 	}

 	helper->report_removing_dependants|=other_packages;

     }

     else

     {

 	if (report_action==PLOVER_TRANSACTION_HELPER_REPORT_UPDATE)

 	    priv->transaction_type|=TRANSACTION_TYPE_REMOVE;

 	priv->transaction_type|=TRANSACTION_TYPE_INSTALL;

 	for(i=0;i<tasked_packages->len;i++)

 	{

 	    s=tasked_packages->strings[i];

 	    if (!plover_vector_contains(helper->report_adding,s))

 		plover_vector_append(helper->report_adding,s);

 	}

 	helper->report_adding_dependencies|=other_packages;

     }

     w=GTK_WIDGET(gtk_builder_get_object(helper->ui,"SIProgressLabel"));

     switch(priv->transaction_type)

     {

 	case TRANSACTION_TYPE_INSTALL:

 	    gtk_label_set_markup(GTK_LABEL(w),

 	      "<b>Installing the Software</b>\n\n"

 	      "Please wait while the Installation Assistant "

 	      "installs the software.\n"

 	      "This may take several minutes.");

 	    break;

 	case TRANSACTION_TYPE_REMOVE:

 	    gtk_label_set_markup(GTK_LABEL(w),

 	      "<b>Removing Packages</b>\n\n"

 	      "Please wait while the Installation Assistant "

 	      "removes packages.\n"

 	      "This may take several minutes.");

 	    break;

 	default:

 	case TRANSACTION_TYPE_UPDATE:

 	    gtk_label_set_markup(GTK_LABEL(w),

 	      "<b>Updating the Software</b>\n\n"

 	      "Please wait while the Installation Assistant "

 	      "updates the software.\n"

 	      "This may take several minutes.");

 	    break;

     }

     plover_vector_free(tasked_packages);

     return TRUE;

 }

 static PloverTransaction *

   plover_transaction_helper_new_transaction(PloverTransactionHelper *helper,

   GError **error)

 {

     gboolean ok;

     const char *base_uri,*prefix;

     GError *tmp_error=NULL;

     PloverTransaction *transaction;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     g_return_val_if_fail(plover_transaction_helper_get_installed(helper) != NULL,NULL);

     prefix=plover_transaction_helper_get_prefix(helper,&tmp_error);

     if (tmp_error)

     {

 	g_propagate_error(error,tmp_error);

 	return NULL;

     }

     transaction=plover_transaction_new();

     plover_transaction_set_prefix(transaction,prefix);

     plover_transaction_set_installed(transaction,helper->installed);

     if (helper->upstream)

 	ok=plover_transaction_set_upstream(transaction,helper->upstream,error);

     else

     {

 	base_uri=plover_transaction_helper_get_base_uri(helper);

 	ok=plover_transaction_set_upstream_from_yum_uri(transaction,base_uri,

 	  error);

     }

     if (!ok)

     {

 	g_object_unref(transaction);

 	transaction=NULL;

     }

     return transaction;

 }

 struct plover_vector *plover_transaction_helper_group_get_default_packages(

   PloverTransactionHelper *helper,const char *group,GError **error)

 {

     gboolean changed;

     struct comps *comps;

     struct comps_group *grp;

     struct comps_requirement *pkg;

     struct plover_vector *default_packages;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     comps=plover_transaction_helper_get_comps(helper,error);

     if (!comps)

 	return NULL;

     grp=plover_comps_lookup_group(comps,group);

     if (!grp)

     {

 	g_set_error(error,PLOVER_GENERAL_ERROR,

 	  PLOVER_GENERAL_ERROR_FAILED,"%s: group not found",group);

 	return NULL;

     }

     default_packages=plover_vector_new();

     do

     {

 	changed=FALSE;

 	for(pkg=grp->packages;pkg;pkg=pkg->next)

 	{

 	    if (plover_vector_contains(default_packages,pkg->name))

 		continue;

 	    if (pkg->type==COMPS_REQUIREMENT_DEFAULT ||

 	      pkg->type==COMPS_REQUIREMENT_MANDATORY ||

 	      pkg->type==COMPS_REQUIREMENT_CONDITIONAL && pkg->requires &&

 	      plover_vector_contains(default_packages,pkg->requires))

 	    {

 		changed=TRUE;

 		plover_vector_append(default_packages,pkg->name);

 	    }

 	}

     } while(changed);

     return default_packages;

 }

 /*

  * Returns TRUE if there is work to be done or FALSE if the packages are

  * already installed or on error.

  */

 gboolean

   plover_transaction_helper_install_packages(PloverTransactionHelper *helper,

   struct plover_vector *packages,GError **error)

 {

     gboolean retval;

     PloverTransaction *transaction;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     g_return_val_if_fail(packages != NULL,FALSE);

     if (!packages->len)

     {

 	g_set_error(error,PLOVER_GENERAL_ERROR,

 	  PLOVER_GENERAL_ERROR_NO_WORK,"No packages listed to be installed");

 	return FALSE;

     }

     transaction=plover_transaction_helper_new_transaction(helper,error);

     if (!transaction)

 	return FALSE;

     if (!plover_transaction_install(transaction,packages->strings,error))

     {

 	g_object_unref(transaction);

 	return FALSE;

     }

     retval=plover_transaction_helper_add_transaction(helper,transaction,

       packages,PLOVER_TRANSACTION_HELPER_REPORT_INSTALL,error);

     g_object_unref(transaction);

     return retval;

 }

 /*

  * Returns TRUE if there is work to be done or FALSE if the group is

  * already installed or on error.

  */

 gboolean

   plover_transaction_helper_install_group(PloverTransactionHelper *helper,

   const char *group,GError **error)

 {

     gboolean retval;

     struct plover_vector *selected_packages;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     selected_packages=plover_transaction_helper_group_get_default_packages(

       helper,group,error);

     if (!selected_packages)

 	return FALSE;

     if (!selected_packages->len)

     {

 	g_set_error(error,PLOVER_GENERAL_ERROR,

 	  PLOVER_GENERAL_ERROR_FAILED,"%s: no default packages",group);

 	plover_vector_free(selected_packages);

 	return FALSE;

     }

     retval=plover_transaction_helper_install_packages(helper,selected_packages,

       error);

     plover_vector_free(selected_packages);

     return retval;

 }

 /*

  * Returns TRUE if there is work to be done or FALSE if the group is

  * not installed or on error.

  */

 gboolean plover_transaction_helper_remove_group(PloverTransactionHelper *helper,

   const char *group,GError **error)

 {

     gboolean retval;

     struct plover_vector *selected_packages;

     PloverTransaction *transaction;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     g_return_val_if_fail(plover_transaction_helper_get_installed(helper) != NULL,FALSE);

     selected_packages=plover_transaction_helper_group_get_default_packages(

       helper,group,error);

     if (!selected_packages)

 	return FALSE;

     if (!selected_packages->len)

     {

 	g_set_error(error,PLOVER_GENERAL_ERROR,

 	  PLOVER_GENERAL_ERROR_FAILED,"%s: no default packages",group);

 	plover_vector_free(selected_packages);

 	return FALSE;

     }

     transaction=plover_transaction_new();

     plover_transaction_set_installed(transaction,helper->installed);

     if (!plover_transaction_remove(transaction,selected_packages->strings,

       error))

     {

 	plover_vector_free(selected_packages);

 	g_object_unref(transaction);

 	return FALSE;

     }

     retval=plover_transaction_helper_add_transaction(helper,transaction,

       NULL,PLOVER_TRANSACTION_HELPER_REPORT_REMOVE,error);

     g_object_unref(transaction);

     plover_vector_free(selected_packages);

     return retval;

 }

 /*

  * Returns TRUE if there is work to be done or FALSE if the group is

  * empty or on error.

  *

  * The default action is to:

  *	- install (and update all) if any of the packages in @group are

  *	  missing or out of date,

  *	- otherwise update all if any packages are out of date,

  *	- otherwise remove ALL packages for distribution-local comps,

  *	- otherwise remove all packages in @group, their dependants and leaves.

  */

 gboolean plover_transaction_helper_default_action_on_group(

   PloverTransactionHelper *helper,const char *group,GError **error)

 {

     gboolean distribution_local=FALSE,retval;

     GError *tmp_err=NULL;

     struct comps *comps;

     struct plover_vector *selected_packages;

     PloverTransaction *transaction;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     selected_packages=plover_transaction_helper_group_get_default_packages(

       helper,group,error);

     if (!selected_packages)

 	return FALSE;

     if (!selected_packages->len)

     {

 	g_set_error(error,PLOVER_GENERAL_ERROR,

 	  PLOVER_GENERAL_ERROR_FAILED,"%s: no default packages",group);

 	plover_vector_free(selected_packages);

 	return FALSE;

     }

     comps=plover_transaction_helper_get_comps(helper,NULL);

     if (comps && comps->database==COMPS_DATABASE_DISTRIBUTION_LOCAL)

 	distribution_local=TRUE;

     transaction=plover_transaction_helper_new_transaction(helper,error);

     if (!transaction)

     {

 	plover_vector_free(selected_packages);

 	return FALSE;

     }

     if (!plover_transaction_install_with_update_all(transaction,

       selected_packages->strings,error))

     {

 	g_object_unref(transaction);

 	plover_vector_free(selected_packages);

 	return FALSE;

     }

     retval=plover_transaction_helper_add_transaction(helper,transaction,

       selected_packages,PLOVER_TRANSACTION_HELPER_REPORT_INSTALL,&tmp_err);

     g_object_unref(transaction);

     if (!retval)

     {

 	if (!g_error_matches(tmp_err,PLOVER_GENERAL_ERROR,

 	  PLOVER_GENERAL_ERROR_NO_WORK))

 	{

 	    g_propagate_error(error,tmp_err);

 	    plover_vector_free(selected_packages);

 	    return FALSE;

 	}

 	g_clear_error(&tmp_err);

 	transaction=plover_transaction_helper_new_transaction(helper,error);

 	if (!transaction)

 	{

 	    plover_vector_free(selected_packages);

 	    return FALSE;

 	}

 	if (!plover_transaction_update(transaction,NULL,error))

 	{

 	    g_object_unref(transaction);

 	    plover_vector_free(selected_packages);

 	    return FALSE;

 	}

 	retval=plover_transaction_helper_add_transaction(helper,transaction,

 	  selected_packages,PLOVER_TRANSACTION_HELPER_REPORT_UPDATE,&tmp_err);

 	g_object_unref(transaction);

 	if (!retval)

 	{

 	    if (!g_error_matches(tmp_err,PLOVER_GENERAL_ERROR,

 	      PLOVER_GENERAL_ERROR_NO_WORK))

 	    {

 		g_propagate_error(error,tmp_err);

 		plover_vector_free(selected_packages);

 		return FALSE;

 	    }

 	    g_clear_error(&tmp_err);

 	    transaction=plover_transaction_helper_new_transaction(helper,error);

 	    if (!transaction)

 	    {

 		plover_vector_free(selected_packages);

 		return FALSE;

 	    }

 	    if (!plover_transaction_remove_with_dependants_and_leaves(

 	      transaction,distribution_local?NULL:selected_packages->strings,

 	      error))

 	    {

 		g_object_unref(transaction);

 		plover_vector_free(selected_packages);

 		return FALSE;

 	    }

 	    retval=plover_transaction_helper_add_transaction(helper,transaction,

 	      NULL,PLOVER_TRANSACTION_HELPER_REPORT_REMOVE,error);

 	    g_object_unref(transaction);

 	}

     }

     plover_vector_free(selected_packages);

     return retval;

 }

 /*

  * Returns TRUE if there is work to be done or FALSE if all updates have

  * already been applied or on error.

  */

 gboolean plover_transaction_helper_update(PloverTransactionHelper *helper,

   GError **error)

 {

     gboolean retval;

     PloverTransaction *transaction;

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     transaction=plover_transaction_helper_new_transaction(helper,error);

     if (!transaction)

 	return FALSE;

     if (!plover_transaction_update(transaction,NULL,error))

     {

 	g_object_unref(transaction);

 	return FALSE;

     }

     retval=plover_transaction_helper_add_transaction(helper,transaction,

       NULL,PLOVER_TRANSACTION_HELPER_REPORT_UPDATE,error);

     g_object_unref(transaction);

     return retval;

 }

 gboolean plover_transaction_helper_get_visible(PloverTransactionHelper *helper)

 {

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),FALSE);

     if (helper->error_dialog)

 	return TRUE;

     else if (!helper->assistant)

 	return FALSE;

     else

 	return gtk_widget_get_visible(GTK_WIDGET(helper->assistant));

 }

 void plover_transaction_helper_present(PloverTransactionHelper *helper)

 {

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     if (helper->error_dialog)

 	gtk_window_present(GTK_WINDOW(helper->error_dialog));

     else if (helper->assistant)

 	gtk_window_present(GTK_WINDOW(helper->assistant));

 }

 static void

   plover_transaction_helper_error_dialog_response(GtkDialog *error_dialog,

   int response_id,PloverTransactionHelper *helper)

 {

     g_signal_handlers_disconnect_by_data(error_dialog,helper);

     if ((GtkWidget *)error_dialog==helper->error_dialog)

     {

 	gtk_widget_destroy(helper->error_dialog);

 	helper->error_dialog=NULL;

 	if (helper->assistant)

 	{

 	    gtk_widget_hide(GTK_WIDGET(helper->assistant));

 	    gtk_assistant_set_current_page(helper->assistant,0);

 	}

 	g_signal_emit(helper,signals[CLOSE],0);

     }

 }

 const char *plover_transaction_helper_get_error(PloverTransactionHelper *helper,

   const GError **error)

 {

     g_return_val_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper),NULL);

     if (!helper->error_dialog)

 	return NULL;

     if (error)

 	*error=helper->error;

     return helper->error_primary_text;

 }

 void plover_transaction_helper_set_error(PloverTransactionHelper *helper,

   const GError *error,const char *primary_text)

 {

     GtkMessageType type;

     GtkWindow *window;

     g_return_if_fail(PLOVER_IS_TRANSACTION_HELPER(helper));

     g_return_if_fail(error != NULL);

     g_return_if_fail(primary_text != NULL);

     if (helper->pulse_handler)

     {

 	g_source_remove(helper->pulse_handler);

 	helper->pulse_handler=0;

     }

     if (helper->error_dialog)

     {

 	gtk_widget_destroy(helper->error_dialog);

 	helper->error_dialog=NULL;

     }

     g_free(helper->error_primary_text);

     helper->error_primary_text=g_strdup(primary_text);

     g_clear_error(&helper->error);

     helper->error=g_error_copy(error);

     if (g_error_matches(error,PLOVER_GENERAL_ERROR,

       PLOVER_GENERAL_ERROR_NO_WORK))

 	type=GTK_MESSAGE_INFO;

     else

 	type=GTK_MESSAGE_ERROR;

     if (helper->assistant)

 	window=GTK_WINDOW(helper->assistant);

     else

     	window=NULL;

     helper->error_dialog=gtk_message_dialog_new(window,

       GTK_DIALOG_DESTROY_WITH_PARENT,type,GTK_BUTTONS_CLOSE,primary_text);

     gtk_message_dialog_format_secondary_text(

       GTK_MESSAGE_DIALOG(helper->error_dialog),error->message);

     gtk_widget_show(helper->error_dialog);

     g_signal_connect(helper->error_dialog,"response",

       G_CALLBACK(plover_transaction_helper_error_dialog_response),helper);

 }