[First cut at navigation (i.e. back/forward) buttons.]

* e-shell-view.c: New member `history' in `EShellViewPrivate'.
(init): Initialize.
(destroy): Unref.
(e_shell_view_display_uri): Make it a no-op if the URI is the same
as the current one.  Also, moved code into `display_uri' and use
it.
(back_clicked_callback): New, callback for the back button on the
folder title bar.
(forward_clicked_callback): Likewise for the forward button.

* e-history.c: New.
* e-history.h: New.

svn path=/trunk/; revision=15798

5 files changed, 416 insertions, 6 deletions

diff --git a/shell/ChangeLog b/shell/ChangeLog
index dd8a9384c1..eeef21d1c9 100644
--- a/shell/ChangeLog
+++ b/shell/ChangeLog
@@ -1,5 +1,20 @@
 2002-02-22  Ettore Perazzoli  <ettore@ximian.com>
 
+	* e-shell-view.c: New member `history' in `EShellViewPrivate'.
+	(init): Initialize.
+	(destroy): Unref.
+	(e_shell_view_display_uri): Make it a no-op if the URI is the same
+	as the current one.  Also, moved code into `display_uri' and use
+	it.
+	(back_clicked_callback): New, callback for the back button on the
+	folder title bar.
+	(forward_clicked_callback): Likewise for the forward button.
+
+	* e-history.c: New.
+	* e-history.h: New.
+
+2002-02-22  Ettore Perazzoli  <ettore@ximian.com>
+
 	* e-shell-view.c (e_shell_view_show_folder_bar):
 	`e_shell_folder_title_bar_set_title_clickable()', not
 	`e_shell_folder_title_bar_set_clickable()'.
diff --git a/shell/Makefile.am b/shell/Makefile.am
index 84cf6e59ec..b884150927 100644
--- a/shell/Makefile.am
+++ b/shell/Makefile.am
@@ -111,6 +111,8 @@ evolution_SOURCES =				\
 	e-folder.h				\
 	e-gray-bar.c				\
 	e-gray-bar.h				\
+	e-history.c				\
+	e-history.h				\
 	e-local-folder.c			\
 	e-local-folder.h			\
 	e-local-storage.c			\
diff --git a/shell/e-history.c b/shell/e-history.c
new file mode 100644
index 0000000000..99579871e1
--- /dev/null
+++ b/shell/e-history.c
@@ -0,0 +1,238 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
+/* e-history.c
+ *
+ * Copyright (C) 2002  Ximian, Inc.
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Author: Ettore Perazzoli <ettore@ximian.com>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "e-history.h"
+
+#include <gal/util/e-util.h>
+
+
+#define PARENT_TYPE gtk_object_get_type ()
+static GtkObjectClass *parent_class = NULL;
+
+struct _EHistoryPrivate {
+	EHistoryItemFreeFunc item_free_function;
+
+	GList *items;
+	GList *current_item;
+};
+
+
+/* GtkObject methods.  */
+
+static void
+impl_destroy (GtkObject *object)
+{
+	EHistory *history;
+	EHistoryPrivate *priv;
+	GList *p;
+
+	history = E_HISTORY (object);
+	priv = history->priv;
+
+	for (p = priv->items; p != NULL; p = p->next)
+		(* priv->item_free_function) (p->data);
+
+	g_list_free (priv->items);
+
+	g_free (priv);
+
+	(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
+}
+
+
+static void
+class_init (GtkObjectClass *object_class)
+{
+	parent_class = gtk_type_class (PARENT_TYPE);
+
+	object_class->destroy = impl_destroy;
+}
+
+static void
+init (EHistory *history)
+{
+	EHistoryPrivate *priv;
+
+	priv = g_new (EHistoryPrivate, 1);
+	priv->items        = NULL;
+	priv->current_item = NULL;
+
+	history->priv = priv;
+
+	GTK_OBJECT_UNSET_FLAGS (history, GTK_FLOATING);
+}
+
+
+void
+e_history_construct  (EHistory *history,
+		      EHistoryItemFreeFunc item_free_function)
+{
+	EHistoryPrivate *priv;
+
+	g_return_if_fail (history != NULL);
+	g_return_if_fail (E_IS_HISTORY (history));
+
+	priv = history->priv;
+
+	priv->item_free_function = item_free_function;
+}
+
+EHistory *
+e_history_new (EHistoryItemFreeFunc item_free_function)
+{
+	EHistory *history;
+
+	history = gtk_type_new (e_history_get_type ());
+	e_history_construct (history, item_free_function);
+
+	return history;
+}
+
+void *
+e_history_prev (EHistory *history)
+{
+	EHistoryPrivate *priv;
+
+	g_return_val_if_fail (history != NULL, NULL);
+	g_return_val_if_fail (E_IS_HISTORY (history), NULL);
+
+	priv = history->priv;
+
+	if (! e_history_has_prev (history))
+		return NULL;
+
+	priv->current_item = priv->current_item->prev;
+	return e_history_get_current (history);
+}
+
+gboolean
+e_history_has_prev (EHistory *history)
+{
+	EHistoryPrivate *priv;
+
+	g_return_val_if_fail (history != NULL, FALSE);
+	g_return_val_if_fail (E_IS_HISTORY (history), FALSE);
+
+	priv = history->priv;
+
+	if (priv->current_item == NULL)
+		return FALSE;
+
+	if (priv->current_item->prev == NULL)
+		return FALSE;
+	else
+		return TRUE;
+}
+
+void *
+e_history_next (EHistory *history)
+{
+	EHistoryPrivate *priv;
+
+	g_return_val_if_fail (history != NULL, NULL);
+	g_return_val_if_fail (E_IS_HISTORY (history), NULL);
+
+	priv = history->priv;
+
+	if (! e_history_has_next (history))
+		return NULL;
+
+	priv->current_item = priv->current_item->next;
+	return e_history_get_current (history);
+}
+
+gboolean
+e_history_has_next (EHistory *history)
+{
+	EHistoryPrivate *priv;
+
+	g_return_val_if_fail (history != NULL, FALSE);
+	g_return_val_if_fail (E_IS_HISTORY (history), FALSE);
+
+	priv = history->priv;
+
+	if (priv->current_item == NULL)
+		return FALSE;
+
+	if (priv->current_item->next == NULL)
+		return FALSE;
+	else
+		return TRUE;
+}
+
+void *
+e_history_get_current (EHistory *history)
+{
+	EHistoryPrivate *priv;
+
+	g_return_val_if_fail (history != NULL, NULL);
+	g_return_val_if_fail (E_IS_HISTORY (history), NULL);
+
+	priv = history->priv;
+
+	if (priv->current_item == NULL)
+		return NULL;
+
+	return priv->current_item->data;
+}
+
+void
+e_history_add (EHistory *history,
+	       void     *data)
+{
+	EHistoryPrivate *priv;
+
+	g_return_if_fail (history != NULL);
+	g_return_if_fail (E_IS_HISTORY (history));
+
+	priv = history->priv;
+
+	if (priv->current_item == NULL) {
+		priv->items = g_list_prepend (priv->items, data);
+		priv->current_item = priv->items;
+
+		return;
+	}
+
+	if (priv->current_item->next != NULL) {
+		GList *p;
+
+		for (p = priv->current_item->next; p != NULL; p = p->next)
+			(* priv->item_free_function) (p->data);
+
+		priv->current_item->next->prev = NULL;
+		g_list_free (priv->current_item->next);
+
+		priv->current_item->next = NULL;
+	}
+
+	g_list_append (priv->current_item, data);
+	priv->current_item = priv->current_item->next;
+}
+
+
+E_MAKE_TYPE (e_history, "EHistory", EHistory, class_init, init, GTK_TYPE_OBJECT)
diff --git a/shell/e-history.h b/shell/e-history.h
new file mode 100644
index 0000000000..f2d4efb1fa
--- /dev/null
+++ b/shell/e-history.h
@@ -0,0 +1,84 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
+/* e-history.h
+ *
+ * Copyright (C) 2002  Ximian, Inc.
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Author: Ettore Perazzoli <ettore@ximian.com>
+ */
+
+#ifndef _E_HISTORY_H_
+#define _E_HISTORY_H_
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <gnome.h>
+
+#ifdef __cplusplus
+extern "C" {
+#pragma }
+#endif /* __cplusplus */
+
+#define E_TYPE_HISTORY			(e_history_get_type ())
+#define E_HISTORY(obj)			(GTK_CHECK_CAST ((obj), E_TYPE_HISTORY, EHistory))
+#define E_HISTORY_CLASS(klass)		(GTK_CHECK_CLASS_CAST ((klass), E_TYPE_HISTORY, EHistoryClass))
+#define E_IS_HISTORY(obj)		(GTK_CHECK_TYPE ((obj), E_TYPE_HISTORY))
+#define E_IS_HISTORY_CLASS(klass)	(GTK_CHECK_CLASS_TYPE ((obj), E_TYPE_HISTORY))
+
+
+typedef struct _EHistory        EHistory;
+typedef struct _EHistoryPrivate EHistoryPrivate;
+typedef struct _EHistoryClass   EHistoryClass;
+
+struct _EHistory {
+	GtkObject parent;
+
+	EHistoryPrivate *priv;
+};
+
+struct _EHistoryClass {
+	GtkObjectClass parent_class;
+};
+
+
+typedef void (* EHistoryItemFreeFunc) (void *data);
+
+
+GtkType    e_history_get_type (void);
+
+void      e_history_construct  (EHistory             *history,
+				EHistoryItemFreeFunc  item_free_function);
+EHistory *e_history_new        (EHistoryItemFreeFunc  item_free_function);
+
+void     *e_history_prev         (EHistory *history);
+gboolean  e_history_has_prev     (EHistory *history);
+
+void     *e_history_next         (EHistory *history);
+gboolean  e_history_has_next     (EHistory *history);
+
+void     *e_history_get_current  (EHistory *history);
+
+void      e_history_add          (EHistory *history,
+				  void     *data);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _E_HISTORY_H_ */
diff --git a/shell/e-shell-view.c b/shell/e-shell-view.c
index 3a5ce7c851..66fedd29b1 100644
--- a/shell/e-shell-view.c
+++ b/shell/e-shell-view.c
@@ -56,6 +56,7 @@
 #include "evolution-shell-view.h"
 
 #include "e-gray-bar.h"
+#include "e-history.h"
 #include "e-shell-constants.h"
 #include "e-shell-folder-title-bar.h"
 #include "e-shell-utils.h"
@@ -89,6 +90,9 @@ struct _EShellViewPrivate {
 	BonoboUIComponent *ui_component;
 	BonoboUIContainer *ui_container;
 
+	/* History of visited (evolution:) URIs. */
+	EHistory *history;
+
 	/* Currently displayed URI.  */
 	char *uri;
 
@@ -180,6 +184,7 @@ static const char *get_storage_set_path_from_uri  (const char *uri);
 
 /* Boo.  */
 static void new_folder_cb (EStorageSet *storage_set, const char *path, void *data);
+static gboolean display_uri (EShellView *shell_view, const char *uri, gboolean add_to_history);
 
 
 /* View handling.  */
@@ -797,6 +802,47 @@ offline_toggle_clicked_cb (GtkButton *button,
 }
 
 
+/* More callbacks: navigation buttons handling.  */
+
+static void
+back_clicked_callback (EShellFolderTitleBar *title_bar,
+		       void *data)
+{
+	EShellView *shell_view;
+	EShellViewPrivate *priv;
+	const char *new_uri;
+
+	shell_view = E_SHELL_VIEW (data);
+	priv = shell_view->priv;
+
+	if (! e_history_has_prev (priv->history))
+		return;
+
+	new_uri = (const char *) e_history_prev (priv->history);
+
+	display_uri (shell_view, new_uri, FALSE);
+}
+
+static void
+forward_clicked_callback (EShellFolderTitleBar *title_bar,
+			  void *data)
+{
+	EShellView *shell_view;
+	EShellViewPrivate *priv;
+	const char *new_uri;
+
+	shell_view = E_SHELL_VIEW (data);
+	priv = shell_view->priv;
+
+	if (! e_history_has_next (priv->history))
+		return;
+
+	new_uri = (const char *) e_history_next (priv->history);
+
+	display_uri (shell_view, new_uri, FALSE);
+}
+
+
 /* Widget setup.  */
 
 static void
@@ -1019,6 +1065,10 @@ setup_widgets (EShellView *shell_view)
 	priv->folder_title_bar = e_shell_folder_title_bar_new ();
 	gtk_signal_connect (GTK_OBJECT (priv->folder_title_bar), "title_toggled",
 			    GTK_SIGNAL_FUNC (title_bar_toggled_cb), shell_view);
+	gtk_signal_connect (GTK_OBJECT (priv->folder_title_bar), "back_clicked",
+			    GTK_SIGNAL_FUNC (back_clicked_callback), shell_view);
+	gtk_signal_connect (GTK_OBJECT (priv->folder_title_bar), "forward_clicked",
+			    GTK_SIGNAL_FUNC (forward_clicked_callback), shell_view);
 
 	priv->view_hpaned = e_hpaned_new ();
 	e_paned_pack1 (E_PANED (priv->view_hpaned), priv->storage_set_view_box, FALSE, FALSE);
@@ -1100,6 +1150,9 @@ destroy (GtkObject *object)
 
 	gtk_object_unref (GTK_OBJECT (priv->tooltips));
 
+	if (priv->history != NULL)
+		gtk_object_unref (GTK_OBJECT (priv->history));
+
 	if (priv->shell != NULL)
 		bonobo_object_unref (BONOBO_OBJECT (priv->shell));
 
@@ -1197,6 +1250,7 @@ init (EShellView *shell_view)
 	priv->shell                   = NULL;
 	priv->corba_interface         = NULL;
 	priv->ui_component            = NULL;
+	priv->history                 = e_history_new ((EHistoryItemFreeFunc) g_free);
 	priv->uri                     = NULL;
 	priv->delayed_selection       = NULL;
 
@@ -1996,19 +2050,23 @@ create_new_view_for_uri (EShellView *shell_view,
 	return TRUE;
 }
 
-gboolean
-e_shell_view_display_uri (EShellView *shell_view,
-			  const char *uri)
+static gboolean
+display_uri (EShellView *shell_view,
+	     const char *uri,
+	     gboolean add_to_history)
 {
 	EShellViewPrivate *priv;
 	View *view;
 	gboolean retval;
 
-	g_return_val_if_fail (shell_view != NULL, FALSE);
-	g_return_val_if_fail (E_IS_SHELL_VIEW (shell_view), FALSE);
-
 	priv = shell_view->priv;
 
+	if (uri == NULL && priv->uri == NULL)
+		return TRUE;
+
+	if (priv->uri != NULL && uri != NULL && strcmp (priv->uri, uri) == 0)
+		return TRUE;
+
 	bonobo_window_freeze (BONOBO_WINDOW (shell_view));
 
 	if (uri == NULL) {
@@ -2047,6 +2105,9 @@ e_shell_view_display_uri (EShellView *shell_view,
 	retval = TRUE;
 
  end:
+	if (add_to_history && retval == TRUE && priv->uri != NULL)
+		e_history_add (priv->history, g_strdup (priv->uri));
+
 	g_free (priv->set_folder_uri);
 	priv->set_folder_uri = NULL;
 
@@ -2068,6 +2129,16 @@ e_shell_view_display_uri (EShellView *shell_view,
 	return retval;
 }
 
+gboolean
+e_shell_view_display_uri (EShellView *shell_view,
+			  const char *uri)
+{
+	g_return_val_if_fail (shell_view != NULL, FALSE);
+	g_return_val_if_fail (E_IS_SHELL_VIEW (shell_view), FALSE);
+
+	return display_uri (shell_view, uri, TRUE);
+}
+
 
 void
 e_shell_view_show_shortcut_bar (EShellView *shell_view,