[gnome-builder/wip/gtk4-port: 395/736] libide/editor: add IdeEditorPageAddin

[Christian Hergert <chergert src gnome org>]

commit 29725ddac129177acd27527408b54edba684658c
Author: Christian Hergert <chergert redhat com>
Date:   Mon Apr 4 17:16:53 2022 -0700

    libide/editor: add IdeEditorPageAddin
    
    This brings back the editor page addin in the new libde-editor.

 src/libide/editor/ide-editor-page-addin.c   | 115 ++++++++++++++++++++++++++++
 src/libide/editor/ide-editor-page-addin.h   |  69 +++++++++++++++++
 src/libide/editor/ide-editor-page-private.h |  19 +++--
 src/libide/editor/ide-editor-page.c         | 100 ++++++++++++++++++++++++
 src/libide/editor/libide-editor.h           |   1 +
 src/libide/editor/meson.build               |   3 +
 6 files changed, 299 insertions(+), 8 deletions(-)
---
diff --git a/src/libide/editor/ide-editor-page-addin.c b/src/libide/editor/ide-editor-page-addin.c
new file mode 100644
index 000000000..86ff6d776
--- /dev/null
+++ b/src/libide/editor/ide-editor-page-addin.c
@@ -0,0 +1,115 @@
+/* ide-editor-page-addin.c
+ *
+ * Copyright 2015-2022 Christian Hergert <christian hergert me>
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#define G_LOG_DOMAIN "ide-editor-page-addin"
+
+#include "config.h"
+
+#include <libide-plugins.h>
+
+#include "ide-editor-page-addin.h"
+#include "ide-editor-page-private.h"
+
+G_DEFINE_INTERFACE (IdeEditorPageAddin, ide_editor_page_addin, G_TYPE_OBJECT)
+
+static void
+ide_editor_page_addin_default_init (IdeEditorPageAddinInterface *iface)
+{
+}
+
+void
+ide_editor_page_addin_load (IdeEditorPageAddin *self,
+                            IdeEditorPage      *page)
+{
+  g_return_if_fail (IDE_IS_EDITOR_PAGE_ADDIN (self));
+  g_return_if_fail (IDE_IS_EDITOR_PAGE (page));
+
+  if (IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->load)
+    IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->load (self, page);
+}
+
+void
+ide_editor_page_addin_unload (IdeEditorPageAddin *self,
+                              IdeEditorPage      *page)
+{
+  g_return_if_fail (IDE_IS_EDITOR_PAGE_ADDIN (self));
+  g_return_if_fail (IDE_IS_EDITOR_PAGE (page));
+
+  if (IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->unload)
+    IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->unload (self, page);
+}
+
+void
+ide_editor_page_addin_language_changed (IdeEditorPageAddin *self,
+                                        const gchar        *language_id)
+{
+  g_return_if_fail (IDE_IS_EDITOR_PAGE_ADDIN (self));
+
+  if (IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->language_changed)
+    IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->language_changed (self, language_id);
+}
+
+void
+ide_editor_page_addin_frame_set (IdeEditorPageAddin *self,
+                                 IdeFrame           *frame)
+{
+  g_return_if_fail (IDE_IS_EDITOR_PAGE_ADDIN (self));
+  g_return_if_fail (IDE_IS_FRAME (frame));
+
+  if (IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->frame_set)
+    IDE_EDITOR_PAGE_ADDIN_GET_IFACE (self)->frame_set (self, frame);
+}
+
+/**
+ * ide_editor_page_addin_find_by_module_name:
+ * @page: an #IdeEditorPage
+ * @module_name: the module name which provides the addin
+ *
+ * This function will locate the #IdeEditorPageAddin that was registered
+ * by the addin named @module_name (which should match the module_name
+ * provided in the .plugin file).
+ *
+ * If no module was found or that module does not implement the
+ * #IdeEditorPageAddinInterface, then %NULL is returned.
+ *
+ * Returns: (transfer none) (nullable): An #IdeEditorPageAddin or %NULL
+ *
+ * Since: 3.32
+ */
+IdeEditorPageAddin *
+ide_editor_page_addin_find_by_module_name (IdeEditorPage *page,
+                                           const gchar   *module_name)
+{
+  PeasExtension *ret = NULL;
+  PeasPluginInfo *plugin_info;
+
+  g_return_val_if_fail (IDE_IS_EDITOR_PAGE (page), NULL);
+  g_return_val_if_fail (page->addins != NULL, NULL);
+  g_return_val_if_fail (module_name != NULL, NULL);
+
+  plugin_info = peas_engine_get_plugin_info (peas_engine_get_default (), module_name);
+
+  if (plugin_info != NULL)
+    ret = ide_extension_set_adapter_get_extension (page->addins, plugin_info);
+  else
+    g_warning ("No addin could be found matching module \"%s\"", module_name);
+
+  return ret ? IDE_EDITOR_PAGE_ADDIN (ret) : NULL;
+}
diff --git a/src/libide/editor/ide-editor-page-addin.h b/src/libide/editor/ide-editor-page-addin.h
new file mode 100644
index 000000000..e0fd9ebfe
--- /dev/null
+++ b/src/libide/editor/ide-editor-page-addin.h
@@ -0,0 +1,69 @@
+/* ide-editor-page-addin.h
+ *
+ * Copyright 2015-2022 Christian Hergert <christian hergert me>
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#if !defined (IDE_EDITOR_INSIDE) && !defined (IDE_EDITOR_COMPILATION)
+# error "Only <libide-editor.h> can be included directly."
+#endif
+
+#include <libide-core.h>
+#include <libide-gui.h>
+
+#include "ide-editor-page.h"
+
+G_BEGIN_DECLS
+
+#define IDE_TYPE_EDITOR_PAGE_ADDIN (ide_editor_page_addin_get_type ())
+
+IDE_AVAILABLE_IN_ALL
+G_DECLARE_INTERFACE (IdeEditorPageAddin, ide_editor_page_addin, IDE, EDITOR_PAGE_ADDIN, GObject)
+
+struct _IdeEditorPageAddinInterface
+{
+  GTypeInterface parent;
+
+  void (*load)               (IdeEditorPageAddin *self,
+                              IdeEditorPage      *page);
+  void (*unload)             (IdeEditorPageAddin *self,
+                              IdeEditorPage      *page);
+  void (*language_changed)   (IdeEditorPageAddin *self,
+                              const gchar        *language_id);
+  void (*frame_set)          (IdeEditorPageAddin *self,
+                              IdeFrame           *frame);
+};
+
+IDE_AVAILABLE_IN_ALL
+void                ide_editor_page_addin_load                (IdeEditorPageAddin *self,
+                                                               IdeEditorPage      *page);
+IDE_AVAILABLE_IN_ALL
+void                ide_editor_page_addin_unload              (IdeEditorPageAddin *self,
+                                                               IdeEditorPage      *page);
+IDE_AVAILABLE_IN_ALL
+void                ide_editor_page_addin_frame_set           (IdeEditorPageAddin *self,
+                                                               IdeFrame           *frame);
+IDE_AVAILABLE_IN_ALL
+void                ide_editor_page_addin_language_changed    (IdeEditorPageAddin *self,
+                                                               const gchar        *language_id);
+IDE_AVAILABLE_IN_ALL
+IdeEditorPageAddin *ide_editor_page_addin_find_by_module_name (IdeEditorPage      *page,
+                                                               const gchar        *module_name);
+
+G_END_DECLS
diff --git a/src/libide/editor/ide-editor-page-private.h b/src/libide/editor/ide-editor-page-private.h
index b7ec71431..9f580c638 100644
--- a/src/libide/editor/ide-editor-page-private.h
+++ b/src/libide/editor/ide-editor-page-private.h
@@ -20,26 +20,29 @@
 
 #pragma once
 
+#include <libide-plugins.h>
+
 #include "ide-editor-page.h"
 
 G_BEGIN_DECLS
 
 struct _IdeEditorPage
 {
-  IdePage            parent_instance;
+  IdePage                  parent_instance;
 
   /* Owned references */
-  IdeBuffer         *buffer;
+  IdeExtensionSetAdapter  *addins;
+  IdeBuffer               *buffer;
 
   /* Settings Management */
-  IdeBindingGroup   *buffer_file_settings;
-  IdeBindingGroup   *view_file_settings;
+  IdeBindingGroup         *buffer_file_settings;
+  IdeBindingGroup         *view_file_settings;
 
   /* Template widgets */
-  IdeSourceView     *view;
-  GtkScrolledWindow *scroller;
-  GtkSourceMap      *map;
-  GtkRevealer       *map_revealer;
+  IdeSourceView           *view;
+  GtkScrolledWindow       *scroller;
+  GtkSourceMap            *map;
+  GtkRevealer             *map_revealer;
 };
 
 void _ide_editor_page_class_actions_init (IdeEditorPageClass *klass);
diff --git a/src/libide/editor/ide-editor-page.c b/src/libide/editor/ide-editor-page.c
index 66ed3ce94..292c50a18 100644
--- a/src/libide/editor/ide-editor-page.c
+++ b/src/libide/editor/ide-editor-page.c
@@ -22,6 +22,7 @@
 
 #include "config.h"
 
+#include "ide-editor-page-addin.h"
 #include "ide-editor-page-private.h"
 
 enum {
@@ -113,11 +114,109 @@ ide_editor_page_focus_enter_cb (IdeEditorPage           *self,
   IDE_EXIT;
 }
 
+static void
+ide_editor_page_notify_frame_set (IdeExtensionSetAdapter *set,
+                                  PeasPluginInfo         *plugin_info,
+                                  PeasExtension          *exten,
+                                  gpointer                user_data)
+{
+  IdeFrame *frame = user_data;
+  IdeEditorPageAddin *addin = (IdeEditorPageAddin *)exten;
+
+  g_assert (IDE_IS_EXTENSION_SET_ADAPTER (set));
+  g_assert (plugin_info != NULL);
+  g_assert (IDE_IS_EDITOR_PAGE_ADDIN (addin));
+  g_assert (IDE_IS_FRAME (frame));
+
+  ide_editor_page_addin_frame_set (addin, frame);
+}
+
+static void
+ide_editor_page_addin_added (IdeExtensionSetAdapter *set,
+                             PeasPluginInfo         *plugin_info,
+                             PeasExtension          *exten,
+                             gpointer                user_data)
+{
+  IdeEditorPage *self = user_data;
+  IdeEditorPageAddin *addin = (IdeEditorPageAddin *)exten;
+
+  g_assert (IDE_IS_EXTENSION_SET_ADAPTER (set));
+  g_assert (plugin_info != NULL);
+  g_assert (IDE_IS_EDITOR_PAGE_ADDIN (addin));
+  g_assert (IDE_IS_EDITOR_PAGE (self));
+
+  ide_editor_page_addin_load (addin, self);
+}
+
+static void
+ide_editor_page_addin_removed (IdeExtensionSetAdapter *set,
+                               PeasPluginInfo         *plugin_info,
+                               PeasExtension          *exten,
+                               gpointer                user_data)
+{
+  IdeEditorPage *self = user_data;
+  IdeEditorPageAddin *addin = (IdeEditorPageAddin *)exten;
+
+  g_assert (IDE_IS_EXTENSION_SET_ADAPTER (set));
+  g_assert (plugin_info != NULL);
+  g_assert (IDE_IS_EDITOR_PAGE_ADDIN (addin));
+  g_assert (IDE_IS_EDITOR_PAGE (self));
+
+  ide_editor_page_addin_unload (addin, self);
+}
+
+static void
+ide_editor_page_root (GtkWidget *widget)
+{
+  IdeEditorPage *self = (IdeEditorPage *)widget;
+  IdeContext *context;
+  GtkWidget *frame;
+
+  IDE_ENTRY;
+
+  GTK_WIDGET_CLASS (ide_editor_page_parent_class)->root (widget);
+
+  context = ide_widget_get_context (widget);
+  frame = gtk_widget_get_ancestor (widget, IDE_TYPE_FRAME);
+
+  if (self->addins == NULL && context != NULL)
+    {
+      self->addins = ide_extension_set_adapter_new (IDE_OBJECT (context),
+                                                    peas_engine_get_default (),
+                                                    IDE_TYPE_EDITOR_PAGE_ADDIN,
+                                                    "Editor-Page-Languages",
+                                                    ide_buffer_get_language_id (self->buffer));
+
+      g_signal_connect (self->addins,
+                        "extension-added",
+                        G_CALLBACK (ide_editor_page_addin_added),
+                        self);
+
+      g_signal_connect (self->addins,
+                        "extension-removed",
+                        G_CALLBACK (ide_editor_page_addin_removed),
+                        self);
+
+      ide_extension_set_adapter_foreach (self->addins,
+                                         ide_editor_page_addin_added,
+                                         self);
+    }
+
+  if (self->addins != NULL && frame != NULL)
+    ide_extension_set_adapter_foreach (self->addins,
+                                       ide_editor_page_notify_frame_set,
+                                       frame);
+
+  IDE_EXIT;
+}
+
 static void
 ide_editor_page_dispose (GObject *object)
 {
   IdeEditorPage *self = (IdeEditorPage *)object;
 
+  ide_clear_and_destroy_object (&self->addins);
+
   g_clear_object (&self->buffer_file_settings);
   g_clear_object (&self->view_file_settings);
 
@@ -183,6 +282,7 @@ ide_editor_page_class_init (IdeEditorPageClass *klass)
   object_class->set_property = ide_editor_page_set_property;
 
   widget_class->grab_focus = ide_editor_page_grab_focus;
+  widget_class->root = ide_editor_page_root;
 
   /**
    * IdeEditorPage:buffer:
diff --git a/src/libide/editor/libide-editor.h b/src/libide/editor/libide-editor.h
index 2f564d66e..6712eac86 100644
--- a/src/libide/editor/libide-editor.h
+++ b/src/libide/editor/libide-editor.h
@@ -23,4 +23,5 @@
 #define IDE_EDITOR_INSIDE
 # include "ide-editor.h"
 # include "ide-editor-page.h"
+# include "ide-editor-page-addin.h"
 #undef IDE_EDITOR_INSIDE
diff --git a/src/libide/editor/meson.build b/src/libide/editor/meson.build
index 60acb502a..ff79b834d 100644
--- a/src/libide/editor/meson.build
+++ b/src/libide/editor/meson.build
@@ -13,6 +13,7 @@ libide_editor_generated_headers = []
 libide_editor_public_headers = [
   'ide-editor.h',
   'ide-editor-page.h',
+  'ide-editor-page-addin.h',
   'libide-editor.h',
 ]
 
@@ -29,6 +30,7 @@ install_headers(libide_editor_public_headers, subdir: libide_editor_header_subdi
 libide_editor_public_sources = [
   'ide-editor.c',
   'ide-editor-page.c',
+  'ide-editor-page-addin.c',
 ]
 
 
@@ -64,6 +66,7 @@ libide_editor_deps = [
 
   libide_core_dep,
   libide_io_dep,
+  libide_plugins_dep,
   libide_projects_dep,
   libide_search_dep,
   libide_sourceview_dep,