[evince] history: Add links when jumping to first or last page.

[Germán Poo-Caamaño <gpoo src gnome org>]

commit d247e9f102929b68993f46430553a7f7b1e2d0f3
Author: Casey Jao <casey jao gmail com>
Date:   Tue Sep 5 10:11:35 2017 -0400

    history: Add links when jumping to first or last page.
    
    shell/ev-window.c:
      * Listen to "scroll" and "scroll-child" of EvView and
        GtkScrolledWindow instances, respectively, and add
        appropriate pages to history.
      * Add pages to history when jumping via window commands.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=785627
    Partially fixes #810 (3/5)

 shell/ev-window.c | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)
---
diff --git a/shell/ev-window.c b/shell/ev-window.c
index a0741500..bf482441 100644
--- a/shell/ev-window.c
+++ b/shell/ev-window.c
@@ -369,6 +369,14 @@ static void        bookmark_activated_cb                   (EvSidebarBookmarks 
*sidebar_bookmar
                                                         gint              old_page,
                                                         gint              page,
                                                         EvWindow         *window);
+static void    scroll_history_cb                       (EvView           *view,
+                                                        GtkScrollType     scroll,
+                                                        gboolean          horizontal,
+                                                        EvWindow         *window);
+static void    scroll_child_history_cb                 (GtkScrolledWindow *scrolled_window,
+                                                        GtkScrollType      scroll,
+                                                        gboolean           horizontal,
+                                                        EvWindow          *window);
 static void     activate_link_cb                        (GObject          *object,
                                                         EvLink           *link,
                                                         EvWindow         *window);
@@ -970,6 +978,67 @@ bookmark_activated_cb (EvSidebarBookmarks *sidebar_bookmarks,
        ev_history_add_page (window->priv->history, page);
 }
 
+static void
+scroll_history_cb (EvView        *view,
+                  GtkScrollType  scroll,
+                  gboolean       horizontal,
+                  EvWindow      *window)
+{
+       if (!window->priv->document)
+               return;
+
+       gint old_page = -1;
+       gint new_page = -1;
+       switch (scroll) {
+               case GTK_SCROLL_START:
+                       old_page = ev_document_model_get_page (window->priv->model);
+                       new_page = 0;
+                       break;
+               case GTK_SCROLL_END:
+                       old_page = ev_document_model_get_page (window->priv->model);
+                       new_page = ev_document_get_n_pages (window->priv->document) - 1;
+                       break;
+               default:
+                       break;
+       }
+       if (old_page >= 0 && new_page >= 0) {
+               ev_history_add_page (window->priv->history, old_page);
+               ev_history_add_page (window->priv->history, new_page);
+       }
+}
+
+static void
+scroll_child_history_cb (GtkScrolledWindow *scrolled_window,
+                        GtkScrollType      scroll,
+                        gboolean           horizontal,
+                        EvWindow          *window)
+{
+       if (!window->priv->document)
+               return;
+
+       if (ev_document_model_get_continuous (window->priv->model) && !horizontal) {
+               gint old_page = -1;
+               gint new_page = -1;
+               switch (scroll) {
+               case GTK_SCROLL_START:
+                       old_page = ev_document_model_get_page (window->priv->model);
+                       new_page = 0;
+                       break;
+               case GTK_SCROLL_END:
+                       old_page = ev_document_model_get_page (window->priv->model);
+                       new_page = ev_document_get_n_pages (window->priv->document) - 1;
+                       break;
+               default:
+                       break;
+               }
+               if (old_page >= 0 && new_page >= 0) {
+                       ev_history_add_page (window->priv->history, old_page);
+                       ev_history_add_page (window->priv->history, new_page);
+
+               }
+       }
+}
+
 static void
 view_selection_changed_cb (EvView   *view,
                           EvWindow *window)
@@ -5047,7 +5116,13 @@ ev_window_cmd_go_first_page (GSimpleAction *action,
        EvWindow *window = user_data;
        EvWindowPrivate *priv = GET_PRIVATE (window);
 
+       gint old_page = ev_document_model_get_page (priv->model);
+       gint new_page = 0;
        ev_document_model_set_page (priv->model, 0);
+       if (old_page >= 0) {
+               ev_history_add_page (priv->history, old_page);
+               ev_history_add_page (priv->history, new_page);
+       }
 }
 
 static void
@@ -5058,8 +5133,16 @@ ev_window_cmd_go_last_page (GSimpleAction *action,
        EvWindow *window = user_data;
        EvWindowPrivate *priv = GET_PRIVATE (window);
 
+       gint old_page = ev_document_model_get_page (priv->model);
+       gint new_page = ev_document_get_n_pages (priv->document) - 1;
+
        ev_document_model_set_page (priv->model,
                                    ev_document_get_n_pages (priv->document) - 1);
+       if (old_page >= 0 && new_page >= 0) {
+               ev_history_add_page (priv->history, old_page);
+               ev_history_add_page (priv->history, new_page);
+       }
+
 }
 
 static void
@@ -7701,6 +7784,12 @@ ev_window_init (EvWindow *ev_window)
        g_signal_connect_object (priv->sidebar_bookmarks, "bookmark-activated",
                                 G_CALLBACK (bookmark_activated_cb),
                                 ev_window, 0);
+       g_signal_connect_object (priv->view, "scroll",
+                                G_CALLBACK (scroll_history_cb),
+                                ev_window, 0);
+       g_signal_connect_object (priv->scrolled_window, "scroll-child",
+                                G_CALLBACK (scroll_child_history_cb),
+                                ev_window, 0);
        g_signal_connect_object (priv->view, "annot-added",
                                 G_CALLBACK (view_annot_added),
                                 ev_window, 0);