From 9a749017454c83164b5c08a02c854c8555fc69c2 Mon Sep 17 00:00:00 2001
From: Alex Anderson <anderson@medicmobile.org>
Date: Tue, 19 Sep 2017 06:25:08 +0200
Subject: [PATCH] Recalculate form fields when page is turned (#3920)

Attempt to work around jr:choice-name() performance issues by reclalculating
fields one more time on form load, and on every page change.  If choice-name()s
only reference fields on different pages, or vice versa, then maybe they will
become usable.

Issue: #3870
---
 Gruntfile.js                        |  4 ----
 patches/3804_jr-choice-name.patch   | 20 --------------------
 static/js/services/enketo.js        |  7 +++++++
 tests/karma/unit/services/enketo.js |  3 ++-
 4 files changed, 9 insertions(+), 25 deletions(-)
 delete mode 100644 patches/3804_jr-choice-name.patch

diff --git a/Gruntfile.js b/Gruntfile.js
index 89a54f17a07..78b0206c80e 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -252,10 +252,6 @@ module.exports = function(grunt) {
             // https://github.com/medic/medic-webapp/issues/2797
             'patch node_modules/pouchdb-adapter-idb/lib/index.js < patches/pouchdb-ignore-safari-check.patch',
 
-            // patch enketo to support cascading of jr:choice-name() update results
-            // https://github.com/medic/medic-webapp/issues/3804
-            'patch node_modules/enketo-core/src/js/output.js < patches/3804_jr-choice-name.patch',
-
             // patch enketo's bootstrap-datepicker dependency so that sass compiles properly
             'patch node_modules/enketo-core/src/widget/date/datepicker-extended.scss < patches/enketo-datepicker-extended-sass-import.patch',
           ];
diff --git a/patches/3804_jr-choice-name.patch b/patches/3804_jr-choice-name.patch
deleted file mode 100644
index c9e8e15901a..00000000000
--- a/patches/3804_jr-choice-name.patch
+++ /dev/null
@@ -1,20 +0,0 @@
-*** node_modules/enketo-core/src/js/output.js	2017-04-20 00:28:05.000000000 +0200
---- static/js/enketo/core/output.js	2017-08-23 15:35:19.000000000 +0200
-***************
-*** 64,69 ****
---- 64,78 ----
-              }
-              if ( $output.text() !== val ) {
-                  $output.text( val );
-+ 
-+ // MEDIC CHANGES : BEGIN
-+                 // For <output>s that are children of choice-groups, trigger
-+                 // dependent calculations in case one is using a jr:choice-name.
-+                 var owName = $output.closest( '.option-wrapper' ).find( 'input' ).attr( 'name' );
-+                 if ( owName ) {
-+                     that.form.calc.update( owName );
-+                 }
-+ // MEDIC CHANGES : END
-              }
-          } );
-      }
diff --git a/static/js/services/enketo.js b/static/js/services/enketo.js
index 368e5c088af..a51e6284dff 100644
--- a/static/js/services/enketo.js
+++ b/static/js/services/enketo.js
@@ -258,6 +258,7 @@ angular.module('inboxServices').service('Enketo',
         window.history.replaceState({ enketo_page_number: 0 }, '');
         overrideNavigationButtons(form, wrapper);
         addPopStateHandler(form, wrapper);
+        forceRecalculate(form);
 
         return form;
       });
@@ -272,6 +273,7 @@ angular.module('inboxServices').service('Enketo',
               if(typeof newPageIndex === 'number') {
                 window.history.pushState({ enketo_page_number: newPageIndex }, '');
               }
+              forceRecalculate(form);
             });
           return false;
         });
@@ -280,6 +282,7 @@ angular.module('inboxServices').service('Enketo',
         .off('.pagemode')
         .on('click.pagemode', function() {
           window.history.back();
+          forceRecalculate(form);
           return false;
         });
     };
@@ -464,6 +467,10 @@ angular.module('inboxServices').service('Enketo',
       });
     };
 
+    var forceRecalculate = function(form) {
+      form.calc.update();
+    };
+
     this.save = function(formInternalId, form, docId) {
       return $q.resolve(form.validate())
         .then(function(valid) {
diff --git a/tests/karma/unit/services/enketo.js b/tests/karma/unit/services/enketo.js
index 1b0365695f3..1a3b4006194 100644
--- a/tests/karma/unit/services/enketo.js
+++ b/tests/karma/unit/services/enketo.js
@@ -91,7 +91,8 @@ describe('Enketo service', function() {
 
     window.EnketoForm = EnketoForm;
     EnketoForm.returns({
-      init: enketoInit
+      init: enketoInit,
+      calc: { update: function() {} }
     });
 
     XmlForm.returns(KarmaUtils.mockPromise(null, { id: 'abc' }));