From 300f194dae9b0434e1f4cd4ff9b57668b6b61361 Mon Sep 17 00:00:00 2001
From: Duy Nguyen <duytnguyendtn.open@gmail.com>
Date: Fri, 13 Sep 2024 16:49:28 -0400
Subject: [PATCH] Allow plugin to follow viewer coords thru panning

---
 .../plugins/virtual_observatory/vo_plugin.py  | 20 ++++++++++++++++++-
 .../plugins/virtual_observatory/vo_plugin.vue | 15 +++++++++++---
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.py b/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.py
index 2b85e8653a..2f88d06b7b 100644
--- a/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.py
+++ b/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.py
@@ -47,6 +47,7 @@ class VoPlugin(PluginTemplateMixin, AddResultsMixin, TableMixin):
     resources_loading = Bool(False).tag(sync=True)
 
     source = Unicode("").tag(sync=True)
+    coord_follow_viewer_pan = Bool(False).tag(sync=True)
     coordframes = List([]).tag(sync=True)
     coordframe_selected = Unicode("icrs").tag(sync=True)
     radius_val = Float(1).tag(sync=True)
@@ -89,7 +90,24 @@ def __init__(self, *args, **kwargs):
         self.hub.subscribe(self, RemoveDataMessage, handler=self.vue_center_on_data)
         self.hub.subscribe(self, LinkUpdatedMessage, handler=self.vue_center_on_data)
 
-    @observe("viewer_selected", type="change")
+    @observe("viewer_selected", "coord_follow_viewer_pan", type="change")
+    def vue_viewer_changed(self, _=None):
+        if not hasattr(self, "viewer"):
+            # mixin object not yet initialized
+            return
+
+        # Clear all existing subscriptions
+        for viewer in self.viewer.viewers:
+            viewer.state.remove_callback('zoom_center_x', self.vue_center_on_data)
+            viewer.state.remove_callback('zoom_center_y', self.vue_center_on_data)
+
+        # Subscribe to selected viewer
+        if self.coord_follow_viewer_pan:
+            self.viewer.selected_obj.state.add_callback('zoom_center_x', self.vue_center_on_data)
+            self.viewer.selected_obj.state.add_callback('zoom_center_y', self.vue_center_on_data)
+
+        self.vue_center_on_data()
+
     def vue_center_on_data(self, _=None):
         """
         If data is present in the default viewer, center the plugin's coordinates on
diff --git a/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.vue b/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.vue
index a1a81af2db..3fb456a493 100644
--- a/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.vue
+++ b/jdaviz/configs/default/plugins/virtual_observatory/vo_plugin.vue
@@ -12,11 +12,20 @@
         :selected.sync="viewer_selected"
         label="Viewer"
         :show_if_single_entry="true"
-        hint="Select a viewer to autofill center coordinates, or Manual for manual coordinate entry."
+        hint="Select a viewer to retrieve center coordinates, or Manual for manual coordinate entry."
       />
 
+      <v-row v-if="viewer_selected !== 'Manual'">
+        <v-switch
+          v-model="coord_follow_viewer_pan"
+          label="Follow Viewer Center"
+          hint="Automatically adjust coordinates as viewer pans and zooms"
+          persistent-hint
+        ></v-switch>
+      </v-row>
+
       <v-row>
-        <div :style="viewer_selected === 'Manual' ? 'width: 100%' : 'width: calc(100% - 32px)'">
+        <div :style="!(viewer_selected !== 'Manual' && !coord_follow_viewer_pan) ? 'width: 100%' : 'width: calc(100% - 32px)'">
           <v-text-field
             v-model="source"
             label="Source/Coordinates"
@@ -26,7 +35,7 @@
             persistent-hint>
           </v-text-field>
         </div>
-        <div v-if="viewer_selected !== 'Manual'" style="line-height:64px; width:32px">
+        <div v-if="viewer_selected !== 'Manual' && !coord_follow_viewer_pan" style="line-height:64px; width:32px">
           <v-btn
             id="autocenterbtn"
             @click="center_on_data"