[gnome-software] Do not set an screenshot error when an image is being shown

[Joaquim Manuel Pereira Rocha <jrocha src gnome org>]

commit f1808bb70e5652d82fb3e54434ccf44da7ab8148
Author: Joaquim Rocha <jrocha endlessm com>
Date:   Wed Nov 9 22:54:15 2016 +0100

    Do not set an screenshot error when an image is being shown
    
    When a screenshot download fails we should only set a user visible
    error if it is not yet showing an image (i.e. a previously cached
    screenshot).
    
    This makes screenshots work again when offline.

 src/gs-screenshot-image.c |   19 +++++++++++++++++--
 1 files changed, 17 insertions(+), 2 deletions(-)
---
diff --git a/src/gs-screenshot-image.c b/src/gs-screenshot-image.c
index 219e881..20e551d 100644
--- a/src/gs-screenshot-image.c
+++ b/src/gs-screenshot-image.c
@@ -54,6 +54,7 @@ struct _GsScreenshotImage
        guint            width;
        guint            height;
        guint            scale;
+       gboolean         showing_image;
 };
 
 G_DEFINE_TYPE (GsScreenshotImage, gs_screenshot_image, GTK_TYPE_BIN)
@@ -77,6 +78,7 @@ gs_screenshot_image_set_error (GsScreenshotImage *ssimg, const gchar *message)
                gtk_widget_hide (ssimg->label_error);
        else
                gtk_widget_show (ssimg->label_error);
+       ssimg->showing_image = FALSE;
 }
 
 static GdkPixbuf *
@@ -170,6 +172,7 @@ as_screenshot_show_image (GsScreenshotImage *ssimg)
        }
 
        gtk_widget_show (GTK_WIDGET (ssimg));
+       ssimg->showing_image = TRUE;
 }
 
 static void
@@ -300,6 +303,10 @@ gs_screenshot_image_complete_cb (SoupSession *session,
                return;
        }
        if (msg->status_code != SOUP_STATUS_OK) {
+               /* if we're already showing an image, then don't set the error
+                * as having an image (even if outdated) is better */
+               if (ssimg->showing_image)
+                       return;
                /* TRANSLATORS: this is when we try to download a screenshot and
                 * we get back 404 */
                gs_screenshot_image_set_error (ssimg, _("Screenshot not found"));
@@ -356,6 +363,11 @@ gs_screenshot_image_set_screenshot (GsScreenshotImage *ssimg,
        if (ssimg->screenshot)
                g_object_unref (ssimg->screenshot);
        ssimg->screenshot = g_object_ref (screenshot);
+
+       /* we reset this flag here too because it referred to the previous
+        * screenshot, and thus avoids potentially assuming that the new
+        * screenshot is shown when it is the previous one instead */
+       ssimg->showing_image = FALSE;
 }
 
 void
@@ -497,8 +509,10 @@ gs_screenshot_image_load_async (GsScreenshotImage *ssimg,
                }
        }
 
-       /* can we load a blurred smaller version of this straight away */
-       if (ssimg->width > AS_IMAGE_THUMBNAIL_WIDTH &&
+       /* if we're not showing a full-size image, we try loading a blurred
+        * smaller version of it straight away */
+       if (!ssimg->showing_image &&
+           ssimg->width > AS_IMAGE_THUMBNAIL_WIDTH &&
            ssimg->height > AS_IMAGE_THUMBNAIL_HEIGHT) {
                const gchar *url_thumb;
                g_autofree gchar *basename_thumb = NULL;
@@ -593,6 +607,7 @@ gs_screenshot_image_init (GsScreenshotImage *ssimg)
 
        ssimg->use_desktop_background = TRUE;
        ssimg->settings = g_settings_new ("org.gnome.software");
+       ssimg->showing_image = FALSE;
 
        gtk_widget_set_has_window (GTK_WIDGET (ssimg), FALSE);
        gtk_widget_init_template (GTK_WIDGET (ssimg));