From 138b23674a2b428c2440f8674af4b20890f1be97 Mon Sep 17 00:00:00 2001
From: Bill Ferguson <wpferguson@gmail.com>
Date: Sun, 9 Aug 2020 00:36:43 -0400
Subject: [PATCH] Added check to ensure we are in lighttable view prior to
 callling darktable.register_lib.  If darktable was invoked in single image
 (darkroom) mode, then an event handler is registered to detect the change
 from darkroom mode to lighttable mode so that we can then call
 darktable.register_lib.

---
 contrib/photils.lua | 53 +++++++++++++++++++++++++++++++++------------
 1 file changed, 39 insertions(+), 14 deletions(-)

diff --git a/contrib/photils.lua b/contrib/photils.lua
index 1c72f4b..cc41b34 100644
--- a/contrib/photils.lua
+++ b/contrib/photils.lua
@@ -91,7 +91,13 @@ local PHOTILS = {
     per_page = 10,
     selected_tags = {},
     in_pagination = false,
-    tagged_image = ""
+    tagged_image = "",
+    module_installed = false,
+    event_registered = false,
+    plugin_display_views = {
+      [dt.gui.views.lighttable] = {"DT_UI_CONTAINER_PANEL_RIGHT_CENTER", 100},
+      [dt.gui.views.darkroom] = {"DT_UI_CONTAINER_PANEL_LEFT_CENTER", 100}
+    },
 }
 
 local GUI = {
@@ -358,6 +364,21 @@ function PHOTILS.on_reset(with_view)
     GUI.attach_button.sensitive = false
 end
 
+local function install_module()
+  if not PHOTILS.module_installed then
+    dt.register_lib(MODULE_NAME,
+        "photils autotagger",
+        true,
+        true,
+        PHOTILS.plugin_display_views,
+        GUI.container,
+        nil,
+        nil
+    )
+    PHOTILS.module_installed = true
+  end
+end
+
 -- add a fix number of buttons
 for _ = 1, PHOTILS.per_page, 1 do
     local btn_tag = dt.new_widget("check_button") {
@@ -402,10 +423,6 @@ table.insert(GUI.container, GUI.stack)
 
 GUI.stack.active = 1
 
-local plugin_display_views = {
-    [dt.gui.views.lighttable] = {"DT_UI_CONTAINER_PANEL_RIGHT_CENTER", 100},
-    [dt.gui.views.darkroom] = {"DT_UI_CONTAINER_PANEL_LEFT_CENTER", 100}
-}
 
 
 -- uses photils: prefix because script settings are all together and not seperated by script
@@ -417,12 +434,20 @@ dt.preferences.register(MODULE_NAME,
                         true)
 
 dt.register_event("mouse-over-image-changed",PHOTILS.image_changed)
-dt.register_lib(MODULE_NAME,
-    "photils autotagger",
-    true,
-    true,
-    plugin_display_views,
-    GUI.container,
-    nil,
-    nil
-)
+
+if dt.gui.current_view().name == "lighttable" then
+  install_module()
+else
+  if not PHOTILS.event_registered then
+    dt.register_event(
+      "view-changed",
+      function(event, old_view, new_view)
+        if new_view.name == "lighttable" and old_view.name == "darkroom" then
+          install_module()
+         end
+      end
+    )
+    PHOTILS.event_registered = true
+  end
+end
+