make sul-embed work with exhibits select image section

app/components/embed/m3_component.html.erb

@@ -4,6 +4,7 @@
       id='sul-embed-m3'
       class='m3'
       data-m3-uri='<%= viewer.manifest_json_url %>'
+      data-viewer-config='<%= viewer.iiif_initial_viewer_config %>'
       data-canvas-id='<%= viewer.canvas_id %>'
       data-canvas-index='<%= viewer.canvas_index %>'
       data-hide-title='<%= viewer.embed_request.hide_title? %>'

app/controllers/embed_controller.rb

@@ -55,7 +55,7 @@ def linted_params
       raise ActionController::BadRequest
     end
     params.permit(:url, :maxwidth, :maxheight, :format, :fullheight, :new_component,
-                  :hide_title, :hide_embed, :hide_download, :hide_search, :min_files_to_search,
+                  :hide_title, :hide_embed, :hide_download, :hide_search, :min_files_to_search, :iiif_initial_viewer_config,
                   :canvas_id, :canvas_index, :search, :suggested_search, :image_tools, :cdl_hold_record_id)
   end
 

app/javascript/src/modules/m3_viewer.js

@@ -12,6 +12,7 @@ import embedModePlugin from '../plugins/embedModePlugin';
 import analyticsPlugin from '../plugins/analyticsPlugin';
 import cdlAuthPlugin from '../plugins/cdlAuthPlugin';
 import xywhPlugin from '../plugins/xywhPlugin';
+import { getExportableState } from 'mirador/dist/es/src/state/selectors';
 
 export default {
   init: function() {
@@ -31,7 +32,10 @@ export default {
       sideBarPanel = 'attribution';
     }
 
-    Mirador.viewer({
+    let viewerConfig;
+    if (data.viewerConfig) { viewerConfig = JSON.parse(data.viewerConfig) }
+
+    const viewerInstance = Mirador.viewer({
       id: 'sul-embed-m3',
       miradorDownloadPlugin: {
         restrictDownloadOnSizeDefinition: true,
@@ -81,6 +85,7 @@ export default {
         suggestedSearches: data.suggestedSearch.length > 0 ? [data.suggestedSearch] : null,
         loadedManifest: data.m3Uri,
         canvasIndex: Number(data.canvasIndex),
+        initialViewerConfig: viewerConfig,
         canvasId: data.canvasId,
         ...(cdl && {
           cdl: {
@@ -136,5 +141,38 @@ export default {
       analyticsPlugin,
       xywhPlugin,
     ].filter(Boolean));
+
+    window.addEventListener('message', (event) => {
+      const regex = /^(stanford\.edu|[\w-]+\.stanford\.edu)$/;
+      if (regex.exec(event.origin) === null) {
+        return;
+      }
+
+      if (event && event.data) {
+        let parsedData;
+        try {
+          parsedData = typeof event.data === 'string' ? JSON.parse(event.data) : event.data;
+        } catch (error) {
+          console.error('Failed to parse event data:', error);
+          return; // Exit if parsing fails
+        }
+
+        if (parsedData.type === "requestState") {
+          const currentState = viewerInstance.store.getState();
+          const exportableState = getExportableState(currentState);
+          const xywhCoords = viewerInstance.container.querySelector('[data-xywh-coords]').dataset.xywhCoords;
+
+          // Send the state back to the parent window
+          window.parent.postMessage(
+            JSON.stringify({
+              type: 'stateResponse',
+              data: {...exportableState, ...{'xywh': xywhCoords}},
+              source: 'sul-embed-m3',
+            }),
+            event.origin
+          );
+        }
+      }
+    });
   }
 };

app/viewers/embed/viewer/m3_viewer.rb

@@ -3,7 +3,7 @@
 module Embed
   module Viewer
     class M3Viewer < CommonViewer
-      delegate :search, :suggested_search, :canvas_id, :cdl_hold_record_id, to: :embed_request
+      delegate :search, :suggested_search, :canvas_id, :cdl_hold_record_id, :iiif_initial_viewer_config, to: :embed_request
 
       def component
         M3Component

app/views/embed/iiif.html.erb

@@ -32,6 +32,7 @@
           data-search='<%= @embed_request.search %>'
           data-suggested-search='<%= @embed_request.suggested_search %>'
           data-image-tools='<%= @embed_request.image_tools %>'
+          data-viewer-config='<%= @embed_request.iiif_initial_viewer_config %>'
           style='height:100%; width:100%'>
         </div>
 

lib/embed/request.rb

@@ -77,7 +77,8 @@ def as_url_params
         :min_files_to_search,
         :canvas_id, :canvas_index,
         :search, :suggested_search,
-        :image_tools
+        :image_tools,
+        :iiif_initial_viewer_config
       )
 
       if p.respond_to? :permit!
@@ -107,6 +108,10 @@ def image_tools
       params[:image_tools]
     end
 
+    def iiif_initial_viewer_config
+      params[:iiif_initial_viewer_config]
+    end
+
     def validate!(url_parameter: true, url_scheme: true, format: true)
       require_url_parameter if url_parameter
       validate_url_scheme if url_scheme