Ask for confirmation when changing the page and

the forms watched do have changes

app/assets/javascripts/watch_form_changes.js.coffee

@@ -0,0 +1,31 @@
+App.WatchFormChanges =
+  forms: ->
+    return $('form[data-watch-changes]')
+
+  msg: ->
+    if($('[data-watch-form-message]').length)
+      return $('[data-watch-form-message]').data('watch-form-message')
+
+  checkChanges: (event) ->
+    console.log(event)
+    changes = false
+    App.WatchFormChanges.forms().each ->
+      form = $(this)
+      if form.serialize() != form.data('watchChanges')
+        changes = true
+    if changes
+      return confirm(App.WatchFormChanges.msg())
+    else
+      return true
+
+  initialize: ->
+    if App.WatchFormChanges.forms().length == 0 || App.WatchFormChanges.msg() == undefined
+      return
+
+    $(document).off('page:before-change').on('page:before-change', (e) -> App.WatchFormChanges.checkChanges(e))
+
+    App.WatchFormChanges.forms().each ->
+      form = $(this)
+      form.data('watchChanges', form.serialize())
+
+    false