Remove the gedit style scheme manager instance

Instead of reimplementing our singleton for the style scheme manager,
leverage the gtksourceview one, so that plugins can simply obtain it
with get_default(). We just need to make sure the search path is set
at startup before any document is opened.
The utility functions to install/uninstall a style scheme are now in
the pref dialog file since in five years we never needed to export them
or use them in another context.

gedit/Makefile.am

@@ -123,7 +123,6 @@ NOINST_H_FILES =			\
 	gedit-session.h			\
 	gedit-settings.h		\
 	gedit-status-combo-box.h	\
-	gedit-style-scheme-manager.h	\
 	gedit-tab-label.h		\
 	gedittextregion.h		\
 	gedit-ui.h			\
@@ -208,7 +207,6 @@ libgedit_c_files =			\
 	gedit-settings.c		\
 	gedit-statusbar.c		\
 	gedit-status-combo-box.c	\
-	gedit-style-scheme-manager.c	\
 	gedit-tab.c 			\
 	gedit-tab-label.c		\
 	gedit-utils.c 			\

gedit/dialogs/gedit-preferences-dialog.c

@@ -35,15 +35,17 @@
 
 #include <stdio.h>
 #include <string.h>
+#include <errno.h>
 
 #include <glib/gi18n.h>
+#include <glib/gstdio.h>
 #include <libpeas-gtk/peas-gtk-plugin-manager.h>
+#include <gtksourceview/gtksourcestyleschememanager.h>
 
 #include "gedit-preferences-dialog.h"
 #include "gedit-utils.h"
 #include "gedit-debug.h"
 #include "gedit-document.h"
-#include "gedit-style-scheme-manager.h"
 #include "gedit-dirs.h"
 #include "gedit-settings.h"
 #include "gedit-utils.h"
@@ -464,16 +466,36 @@ setup_font_colors_page_font_section (GeditPreferencesDialog *dlg)
 			 G_SETTINGS_BIND_GET | G_SETTINGS_BIND_SET);
 }
 
+static gboolean
+is_gedit_user_style_scheme (const gchar *scheme_id)
+{
+	GtkSourceStyleSchemeManager *manager;
+	GtkSourceStyleScheme *scheme;
+	gboolean res = FALSE;
+
+	manager = gtk_source_style_scheme_manager_get_default ();
+	scheme = gtk_source_style_scheme_manager_get_scheme (manager, scheme_id);
+	if (scheme != NULL)
+	{
+		const gchar *filename;
+
+		filename = gtk_source_style_scheme_get_filename (scheme);
+		if (filename != NULL)
+		{
+			res = g_str_has_prefix (filename, gedit_dirs_get_user_styles_dir ());
+		}
+	}
+
+	return res;
+}
+
 static void
 set_buttons_sensisitivity_according_to_scheme (GeditPreferencesDialog *dlg,
 					       const gchar            *scheme_id)
 {
 	gboolean editable;
-
-	editable = (scheme_id != NULL) && 
-	           _gedit_style_scheme_manager_scheme_is_gedit_user_scheme (
-						gedit_get_style_scheme_manager (),
-						scheme_id);
+
+	editable = ((scheme_id != NULL) && is_gedit_user_style_scheme (scheme_id));
 
 	gtk_widget_set_sensitive (dlg->priv->uninstall_scheme_button,
 				  editable);
@@ -509,9 +531,10 @@ static const gchar *
 ensure_color_scheme_id (GeditPreferencesDialog *dlg,
 			const gchar            *id)
 {
+	GtkSourceStyleSchemeManager *manager;
 	GtkSourceStyleScheme *scheme = NULL;
-	GtkSourceStyleSchemeManager *manager = gedit_get_style_scheme_manager ();
 
+	manager = gtk_source_style_scheme_manager_get_default ();
 	if (id == NULL)
 	{
 		gchar *pref_id;
@@ -545,13 +568,10 @@ ensure_color_scheme_id (GeditPreferencesDialog *dlg,
 	return 	gtk_source_style_scheme_get_id (scheme);
 }
 
-/* If def_id is NULL, use the default scheme as returned by 
- * gedit_style_scheme_manager_get_default_scheme. If this one returns NULL
- * use the first available scheme as default */
 static const gchar *
 populate_color_scheme_list (GeditPreferencesDialog *dlg, const gchar *def_id)
 {
-	GtkSourceStyleSchemeManager *sm;
+	GtkSourceStyleSchemeManager *manager;
 	const gchar * const *ids;
 	gint i;
 
@@ -565,16 +585,16 @@ populate_color_scheme_list (GeditPreferencesDialog *dlg, const gchar *def_id)
 		return NULL;
 	}
 
-	sm = gedit_get_style_scheme_manager ();
-	ids = gtk_source_style_scheme_manager_get_scheme_ids (sm);
+	manager = gtk_source_style_scheme_manager_get_default ();
+	ids = gtk_source_style_scheme_manager_get_scheme_ids (manager);
 	for (i = 0; ids[i] != NULL; i++)
 	{
 		GtkSourceStyleScheme *scheme;
 		const gchar *name;
 		const gchar *description;
 		GtkTreeIter iter;
 
-		scheme = gtk_source_style_scheme_manager_get_scheme (sm, ids[i]);
+		scheme = gtk_source_style_scheme_manager_get_scheme (manager, ids[i]);
 
 		name = gtk_source_style_scheme_get_name (scheme);
 		description = gtk_source_style_scheme_get_description (scheme);
@@ -600,6 +620,217 @@ populate_color_scheme_list (GeditPreferencesDialog *dlg, const gchar *def_id)
 	return def_id;
 }
 
+/*
+ * file_copy:
+ * @name: a pointer to a %NULL-terminated string, that names
+ * the file to be copied, in the GLib file name encoding
+ * @dest_name: a pointer to a %NULL-terminated string, that is the
+ * name for the destination file, in the GLib file name encoding
+ * @error: return location for a #GError, or %NULL
+ *
+ * Copies file @name to @dest_name.
+ *
+ * If the call was successful, it returns %TRUE. If the call was not
+ * successful, it returns %FALSE and sets @error. The error domain
+ * is #G_FILE_ERROR. Possible error
+ * codes are those in the #GFileError enumeration.
+ *
+ * Return value: %TRUE on success, %FALSE otherwise.
+ */
+static gboolean
+file_copy (const gchar  *name,
+	   const gchar  *dest_name,
+	   GError      **error)
+{
+	gchar *contents;
+	gsize length;
+	gchar *dest_dir;
+
+	/* FIXME - Paolo (Aug. 13, 2007):
+	 * Since the style scheme files are relatively small, we can implement
+	 * file copy getting all the content of the source file in a buffer and
+	 * then write the content to the destination file. In this way we
+	 * can use the g_file_get_contents and g_file_set_contents and avoid to
+	 * write custom code to copy the file (with sane error management).
+	 * If needed we can improve this code later. */
+
+	g_return_val_if_fail (name != NULL, FALSE);
+	g_return_val_if_fail (dest_name != NULL, FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	/* Note: we allow to copy a file to itself since this is not a problem
+	 * in our use case */
+
+	/* Ensure the destination directory exists */
+	dest_dir = g_path_get_dirname (dest_name);
+
+	errno = 0;
+	if (g_mkdir_with_parents (dest_dir, 0755) != 0)
+	{
+		gint save_errno = errno;
+		gchar *display_filename = g_filename_display_name (dest_dir);
+
+		g_set_error (error,
+			     G_FILE_ERROR,
+			     g_file_error_from_errno (save_errno),
+			     _("Directory '%s' could not be created: g_mkdir_with_parents() failed: %s"),
+			     display_filename,
+			     g_strerror (save_errno));
+
+		g_free (dest_dir);
+		g_free (display_filename);
+
+		return FALSE;
+	}
+
+	g_free (dest_dir);
+
+	if (!g_file_get_contents (name, &contents, &length, error))
+		return FALSE;
+
+	if (!g_file_set_contents (dest_name, contents, length, error))
+		return FALSE;
+
+	g_free (contents);
+
+	return TRUE;
+}
+
+/*
+ * install_style_scheme:
+ * @manager: a #GtkSourceStyleSchemeManager
+ * @fname: the file name of the style scheme to be installed
+ *
+ * Install a new user scheme.
+ * This function copies @fname in #GEDIT_STYLES_DIR and ask the style manager to
+ * recompute the list of available style schemes. It then checks if a style
+ * scheme with the right file name exists.
+ *
+ * If the call was succesful, it returns the id of the installed scheme
+ * otherwise %NULL.
+ *
+ * Return value: the id of the installed scheme, %NULL otherwise.
+ */
+static const gchar *
+install_style_scheme (const gchar *fname)
+{
+	GtkSourceStyleSchemeManager *manager;
+	gchar *new_file_name = NULL;
+	gchar *dirname;
+	const gchar *styles_dir;
+	GError *error = NULL;
+	gboolean copied = FALSE;
+	const gchar* const *ids;
+
+	g_return_val_if_fail (fname != NULL, NULL);
+
+	manager = gtk_source_style_scheme_manager_get_default ();
+
+	dirname = g_path_get_dirname (fname);
+	styles_dir = gedit_dirs_get_user_styles_dir ();
+
+	if (strcmp (dirname, styles_dir) != 0)
+	{
+		gchar *basename;
+
+		basename = g_path_get_basename (fname);
+		new_file_name = g_build_filename (styles_dir, basename, NULL);
+		g_free (basename);
+
+		/* Copy the style scheme file into GEDIT_STYLES_DIR */
+		if (!file_copy (fname, new_file_name, &error))
+		{
+			g_free (new_file_name);
+
+			g_message ("Cannot install style scheme:\n%s",
+				   error->message);
+
+			return NULL;
+		}
+
+		copied = TRUE;
+	}
+	else
+	{
+		new_file_name = g_strdup (fname);
+	}
+
+	g_free (dirname);
+
+	/* Reload the available style schemes */
+	gtk_source_style_scheme_manager_force_rescan (manager);
+
+	/* Check the new style scheme has been actually installed */
+	ids = gtk_source_style_scheme_manager_get_scheme_ids (manager);
+
+	while (*ids != NULL)
+	{
+		GtkSourceStyleScheme *scheme;
+		const gchar *filename;
+
+		scheme = gtk_source_style_scheme_manager_get_scheme (manager, *ids);
+
+		filename = gtk_source_style_scheme_get_filename (scheme);
+
+		if (filename && (strcmp (filename, new_file_name) == 0))
+		{
+			/* The style scheme has been correctly installed */
+			g_free (new_file_name);
+
+			return gtk_source_style_scheme_get_id (scheme);
+		}
+		++ids;
+	}
+
+	/* The style scheme has not been correctly installed */
+	if (copied)
+		g_unlink (new_file_name);
+
+	g_free (new_file_name);
+
+	return NULL;
+}
+
+/**
+ * uninstall_style_scheme:
+ * @manager: a #GtkSourceStyleSchemeManager
+ * @id: the id of the style scheme to be uninstalled
+ *
+ * Uninstall a user scheme.
+ *
+ * If the call was succesful, it returns %TRUE
+ * otherwise %FALSE.
+ *
+ * Return value: %TRUE on success, %FALSE otherwise.
+ */
+static gboolean
+uninstall_style_scheme (const gchar *id)
+{
+	GtkSourceStyleSchemeManager *manager;
+	GtkSourceStyleScheme *scheme;
+	const gchar *filename;
+
+	g_return_val_if_fail (id != NULL, FALSE);
+
+	manager = gtk_source_style_scheme_manager_get_default ();
+
+	scheme = gtk_source_style_scheme_manager_get_scheme (manager, id);
+	if (scheme == NULL)
+		return FALSE;
+
+	filename = gtk_source_style_scheme_get_filename (scheme);
+	if (filename == NULL)
+		return FALSE;
+
+	if (g_unlink (filename) == -1)
+		return FALSE;
+
+	/* Reload the available style schemes */
+	gtk_source_style_scheme_manager_force_rescan (manager);
+
+	return TRUE;
+}
+
 static void
 add_scheme_chooser_response_cb (GtkDialog              *chooser, 
 				gint                    res_id,
@@ -619,10 +850,8 @@ add_scheme_chooser_response_cb (GtkDialog              *chooser,
 		return;
 
 	gtk_widget_hide (GTK_WIDGET (chooser));
-
-	scheme_id = _gedit_style_scheme_manager_install_scheme (
-					gedit_get_style_scheme_manager (),
-					filename);
+
+	scheme_id = install_style_scheme (filename);
 	g_free (filename);
 
 	if (scheme_id == NULL)
@@ -719,7 +948,7 @@ uninstall_scheme_clicked (GtkButton              *button,
 				    NAME_COLUMN, &name,
 				    -1);
 
-		if (!_gedit_style_scheme_manager_uninstall_scheme (gedit_get_style_scheme_manager (), id))
+		if (!uninstall_style_scheme (id))
 		{
 			gedit_warning (GTK_WINDOW (dlg),
 				       _("Could not remove color scheme \"%s\"."),

gedit/gedit-app.c

@@ -37,6 +37,7 @@
 
 #include <glib/gi18n.h>
 #include <libpeas/peas-extension-set.h>
+#include <gtksourceview/gtksourcestyleschememanager.h>
 
 #include "gedit-app.h"
 #include "gedit-commands.h"
@@ -652,6 +653,8 @@ extension_removed (PeasExtensionSet *extensions,
 static void
 gedit_app_init (GeditApp *app)
 {
+	GtkSourceStyleSchemeManager *manager;
+
 	app->priv = GEDIT_APP_GET_PRIVATE (app);
 
 	/* Load settings */
@@ -661,6 +664,15 @@ gedit_app_init (GeditApp *app)
 	/* initial lockdown state */
 	app->priv->lockdown = gedit_settings_get_lockdown (GEDIT_SETTINGS (app->priv->settings));
 
+	/*
+	 * We use the default gtksourceview style scheme manager so that plugins
+	 * can obtain it easily without a gedit specific api, but we need to
+	 * add our search path at startup before the manager is actually used.
+	 */
+	manager = gtk_source_style_scheme_manager_get_default ();
+	gtk_source_style_scheme_manager_append_search_path (manager,
+							    gedit_dirs_get_user_styles_dir ());
+
 	app->priv->extensions = peas_extension_set_new (PEAS_ENGINE (gedit_plugins_engine_get_default ()),
 							GEDIT_TYPE_APP_ACTIVATABLE,
 							"app", app,