Admin "what this form submission changed" page

app/controllers/form_submissions_controller.rb

@@ -21,4 +21,14 @@ def show
     @form_submission = FormSubmission.find(params[:id])
     authorize! @form_submission
   end
+
+  # Admin-only audit of everything this submission's smart-field answers changed
+  # across records, read back from the stamped Ahoy lifecycle events.
+  def changes
+    @form_submission = FormSubmission.find(params[:id])
+    authorize! @form_submission, to: :changes?
+    changes = FormSubmissionChanges.new(@form_submission)
+    @change_groups = changes.edited_groups
+    @changed_count = changes.edited_count
+  end
 end

app/policies/form_submission_policy.rb

@@ -10,6 +10,10 @@ def show?
     admin? || (slug.present? && record.slug == slug)
   end
 
+  def changes?
+    admin?
+  end
+
   def ticket?
     admin? || (slug.present? && record.slug == slug)
   end

app/services/form_submission_changes.rb

@@ -0,0 +1,138 @@
+# Reconstructs everything one form submission changed across records, read back
+# from the Ahoy lifecycle events each write already emits (stamped with the
+# submission id by the registration flow). Groups the changes by the record they
+# happened to and labels each with what actually happened to it — added, removed,
+# replaced, or filled (a blank) — for the admin "what this submission changed" page.
+class FormSubmissionChanges
+  # The records whose changes are worth surfacing. Bookkeeping rows a submission
+  # also touches (the submission, its answers, the registration link) are noise here.
+  RELEVANT_TYPES = %w[Person Organization Address ContactMethod Affiliation SectorableItem CategorizableItem].freeze
+  GROUP_ORDER = %w[Person Organization Affiliation].freeze
+  IGNORED_ATTRIBUTES = %w[id created_at updated_at slug locality].freeze
+  # Friendlier than humanizing the raw column (e.g. "value" on a phone contact).
+  ATTRIBUTE_LABELS = {
+    "website_url" => "Website", "agency_type" => "Type", "value" => "Phone",
+    "racial_ethnic_identity" => "Racial / ethnic identity", "zip_code" => "ZIP",
+    "street_address" => "Street address"
+  }.freeze
+
+  Change = Struct.new(:outcome, :label, :value, :previous_value, keyword_init: true)
+  Group = Struct.new(:record_type, :title, :changes, keyword_init: true)
+
+  def initialize(form_submission)
+    @form_submission = form_submission
+  end
+
+  def groups
+    relevant_events
+      .group_by { |event| owner_key(event) }
+      .filter_map { |(type, id), events| build_group(type, id, events) }
+      .reject { |group| group.changes.empty? }
+      .sort_by { |group| [ GROUP_ORDER.index(group.record_type) || GROUP_ORDER.size, group.title.to_s ] }
+  end
+
+  # A submission "changed" a value only when it edited a record that already
+  # existed — a value replaced, or a blank filled, on that record (both come from
+  # an update event). Creating new records and adding tags are a new submission's
+  # own data, not edits, so they don't count. (This is why linking an org that
+  # wasn't a clean match can raise the count: the fill lands on the existing org.)
+  EDIT_OUTCOMES = %w[Replaced Filled].freeze
+
+  def edited_groups
+    groups.filter_map do |group|
+      edits = group.changes.select { |change| EDIT_OUTCOMES.include?(change.outcome) }
+      Group.new(record_type: group.record_type, title: group.title, changes: edits) if edits.any?
+    end
+  end
+
+  def edited_count
+    relevant_events.sum { |event| attribute_changes(event.properties["changes"] || {}).size }
+  end
+
+  def edited?
+    edited_count.positive?
+  end
+
+  private
+
+  def relevant_events
+    Ahoy::Event
+      .where("properties->>'$.form_submission_id' = ?", @form_submission.id.to_s)
+      .order(:time, :id)
+      .select { |event| event.properties["resource_type"].in?(RELEVANT_TYPES) }
+  end
+
+  # A tag row belongs to the person/organization it tags, not to itself, so its
+  # changes group under that owner. Everything else owns its own changes.
+  def owner_key(event)
+    props = event.properties
+    case props["resource_type"]
+    when "SectorableItem" then [ props.dig("attributes", "sectorable_type"), props.dig("attributes", "sectorable_id") ]
+    when "CategorizableItem" then [ props.dig("attributes", "categorizable_type"), props.dig("attributes", "categorizable_id") ]
+    when "Address", "ContactMethod" then [ props.dig("attributes", "addressable_type") || props.dig("attributes", "contactable_type"), props.dig("attributes", "addressable_id") || props.dig("attributes", "contactable_id") ]
+    else [ props["resource_type"], props["resource_id"] ]
+    end
+  end
+
+  def build_group(type, id, events)
+    changes = events.flat_map { |event| changes_for(event) }.compact
+    Group.new(record_type: type, title: owner_title(type, id), changes: changes)
+  end
+
+  def changes_for(event)
+    action = event.name.split(".").first
+    props = event.properties
+
+    return attribute_changes(props["changes"]) if props["changes"].present?
+    return [ tag_change(action, event) ] if props["resource_type"].in?(%w[SectorableItem CategorizableItem])
+    return [ record_change(action, event) ] if action.in?(%w[create destroy])
+
+    []
+  end
+
+  def attribute_changes(changes)
+    changes.except(*IGNORED_ATTRIBUTES).filter_map do |attribute, before_after|
+      before, after = before_after.values_at("before", "after")
+      next if after.blank? && before.blank?
+
+      Change.new(
+        outcome: before.present? ? "Replaced" : "Filled",
+        label: ATTRIBUTE_LABELS[attribute] || attribute.humanize,
+        value: display_value(after),
+        previous_value: display_value(before)
+      )
+    end
+  end
+
+  def tag_change(action, event)
+    props = event.properties
+    if props["resource_type"] == "SectorableItem"
+      name = Sector.find_by(id: props.dig("attributes", "sector_id"))&.name
+      kind = "sector"
+    else
+      name = Category.find_by(id: props.dig("attributes", "category_id"))&.name
+      kind = "age group"
+    end
+    primary = props.dig("attributes", "is_primary") ? " (primary)" : ""
+    Change.new(outcome: action == "destroy" ? "Removed" : "Added", label: kind.humanize, value: "#{name}#{primary}")
+  end
+
+  def record_change(action, event)
+    Change.new(
+      outcome: action == "destroy" ? "Removed" : "Added",
+      label: event.properties["resource_type"].underscore.humanize,
+      value: event.properties["resource_title"]
+    )
+  end
+
+  def owner_title(type, id)
+    return type.to_s if id.blank?
+
+    record = type.safe_constantize&.find_by(id: id)
+    record&.try(:full_name).presence || record&.try(:name).presence || "#{type} ##{id}"
+  end
+
+  def display_value(value)
+    value.is_a?(Array) ? value.join(", ") : value
+  end
+end

app/views/event_registrations/link_organization.html.erb

@@ -68,6 +68,21 @@
               </li>
             <% end %>
           </ul>
+          <%# Admin-only jump to the audit of the values these answers overwrote —
+              shown only once the submission has overwritten something (e.g. after
+              linking an org that wasn't a clean match writes onto it). %>
+          <% changes_submission = present_entries.first[:submission] %>
+          <% submission_changes = changes_submission && FormSubmissionChanges.new(changes_submission) %>
+          <% if submission_changes&.edited? && allowed_to?(:changes?, changes_submission) %>
+            <%= link_to changes_form_submission_path(changes_submission, return_to: "link_organization", event_registration_id: @event_registration.id),
+                        data: { turbo_frame: "_top" },
+                        class: "group mt-3 flex items-center gap-2 rounded-md border border-blue-200 bg-blue-50 px-3 py-2 text-sm font-semibold text-blue-900 hover:bg-blue-100" do %>
+              <i class="fa-solid fa-circle-info text-blue-500"></i>
+              What this registration's form changed
+              <span class="rounded-full bg-blue-200 px-1.5 text-2xs"><%= submission_changes.edited_count %></span>
+              <i class="fa-solid fa-arrow-right text-xs ml-auto text-blue-400 transition-transform group-hover:translate-x-0.5"></i>
+            <% end %>
+          <% end %>
         <% elsif @form_submission %>
           <p class="text-sm text-gray-500">
             No organization was submitted on the <%= link_to "registration form submission", event_registrant_submissions_path(@event_registration.event, person_id: @person.id, form_submission_id: @form_submission.id, return_to: "link_organization", link_org_return_to: params[:return_to]), target: "_blank", class: "text-blue-600 hover:underline", data: { turbo_frame: "_top" } %>.

app/views/events/form_submissions/show.html.erb

@@ -19,6 +19,19 @@
         <p class="text-xs text-gray-500">Submitted <%= submission.created_at.strftime("%B %d, %Y at %l:%M %P") %></p>
       </div>
 
+      <%# Admin-only jump to the audit of the values this submission overwrote. %>
+      <% submission_changes = FormSubmissionChanges.new(submission) %>
+      <% if allowed_to?(:changes?, submission) && submission_changes.edited? %>
+        <%= link_to changes_form_submission_path(submission, return_to: "event_registrant_submissions"),
+                    class: "group mb-5 flex items-center gap-2 rounded-md border border-blue-200 bg-blue-50 px-3 py-2 text-sm font-semibold text-blue-900 hover:bg-blue-100" do %>
+          <i class="fa-solid fa-circle-info text-blue-500"></i>
+          What this submission changed
+          <span class="rounded-full bg-blue-200 px-1.5 text-2xs"><%= submission_changes.edited_count %></span>
+          <span class="ml-1 rounded-full bg-white/70 text-blue-700 px-1.5 py-0.5 text-2xs font-normal border border-blue-200"><i class="fa-solid fa-lock text-2xs mr-0.5"></i>admin</span>
+          <i class="fa-solid fa-arrow-right text-xs ml-auto text-blue-400 transition-transform group-hover:translate-x-0.5"></i>
+        <% end %>
+      <% end %>
+
       <% sections = [] %>
       <% current = nil %>
 

app/views/form_submissions/changes.html.erb

@@ -0,0 +1,81 @@
+<% content_for(:page_bg_class, "admin-only bg-blue-100") %>
+<%
+  # Reachable from the linked-organizations page and from a submission view, so the
+  # eyebrow returns to whichever origin sent us.
+  back_link = case params[:return_to]
+  when "link_organization"
+    { label: "← Back to linked organizations", path: link_organization_event_registration_path(params[:event_registration_id]) } if params[:event_registration_id].present?
+  when "event_registrant_submissions"
+    event = @form_submission.resolved_event
+    { label: "← Back to submissions", path: event_registrant_submissions_path(event, person_id: @form_submission.person_id) } if event
+  end
+  back_link ||= { label: "← Back to submission", path: form_submission_path(@form_submission) }
+
+  outcome_chip = {
+    "Added"    => "bg-emerald-100 text-emerald-800 border-emerald-200",
+    "Removed"  => "bg-amber-100 text-amber-800 border-amber-200",
+    "Replaced" => "bg-rose-100 text-rose-800 border-rose-200",
+    "Filled"   => "bg-slate-200 text-slate-700 border-slate-300"
+  }
+  group_icon = {
+    "Person" => "fa-user", "Organization" => "fa-building", "Affiliation" => "fa-link"
+  }
+%>
+<div class="max-w-3xl mx-auto py-8 px-4">
+  <div class="mb-4">
+    <%= link_to back_link[:label], back_link[:path], class: "text-sm text-gray-500 hover:text-gray-700" %>
+  </div>
+
+  <div class="rounded-2xl overflow-hidden shadow-lg ring-1 ring-black/5 bg-white">
+    <div class="px-6 pt-5 pb-5 border-b border-gray-100">
+      <div class="flex items-center gap-3">
+        <div class="flex h-11 w-11 shrink-0 items-center justify-center rounded-xl bg-blue-900 text-white">
+          <i class="fa-solid fa-wand-magic-sparkles"></i>
+        </div>
+        <div class="min-w-0">
+          <div class="flex items-center gap-2">
+            <h1 class="text-2xl font-bold tracking-tight text-gray-900">What this form submission changed</h1>
+            <span class="inline-flex items-center gap-1 rounded-full bg-blue-100 text-blue-900 px-2 py-0.5 text-xs font-semibold uppercase tracking-wide"><i class="fa-solid fa-lock text-2xs"></i> Admin</span>
+          </div>
+          <p class="text-sm text-gray-500">
+            <%= @form_submission.person&.full_name %> · <%= @form_submission.form&.display_name || @form_submission.form&.name %> · <%= @form_submission.created_at.to_date.to_fs(:long) %>
+          </p>
+        </div>
+      </div>
+    </div>
+
+    <div class="px-6 py-6 space-y-5">
+      <% if @change_groups.any? %>
+        <p class="text-xs text-gray-500"><strong><%= pluralize(@changed_count, "value") %></strong> this submission changed on records that already existed — a value replaced or a blank filled. A replaced value keeps its previous entry so it can be put back. (Brand-new records and added tags aren't shown — they're new data, not changes.)</p>
+
+        <% @change_groups.each do |group| %>
+          <section class="rounded-xl border border-gray-200 overflow-hidden">
+            <div class="flex items-center gap-2 px-5 py-3 bg-gray-50 border-b border-gray-200">
+              <i class="fa-solid <%= group_icon.fetch(group.record_type, "fa-database") %> text-gray-500"></i>
+              <h2 class="text-sm font-semibold text-gray-800"><%= group.record_type.underscore.humanize %><% if group.title.present? %> — <%= group.title %><% end %></h2>
+            </div>
+            <ul class="divide-y divide-gray-100">
+              <% group.changes.each do |change| %>
+                <li class="px-5 py-3 flex items-start justify-between gap-3 text-sm">
+                  <div class="min-w-0">
+                    <p class="text-gray-500"><%= change.label %></p>
+                    <p class="text-gray-800">
+                      <span class="font-medium"><%= change.value.presence || "—" %></span><%
+                      %><% if change.outcome == "Replaced" && change.previous_value.present? %> <span class="text-rose-600">(replaced “<%= change.previous_value %>”)</span><% end %>
+                    </p>
+                  </div>
+                  <span class="shrink-0 inline-flex items-center rounded-full border px-2 py-0.5 text-xs font-semibold <%= outcome_chip.fetch(change.outcome, "bg-gray-100 text-gray-700 border-gray-200") %>"><%= change.outcome %></span>
+                </li>
+              <% end %>
+            </ul>
+          </section>
+        <% end %>
+      <% else %>
+        <div class="rounded-xl border border-gray-200 bg-gray-50 px-5 py-8 text-center text-gray-500">
+          <i class="fa-solid fa-circle-check text-gray-400 text-xl mb-2"></i>
+          <p>This submission didn't change any existing records.</p>
+        </div>
+      <% end %>
+    </div>
+  </div>
+</div>

app/views/form_submissions/show.html.erb

@@ -32,6 +32,19 @@
       <div class="absolute inset-x-0 bottom-0 h-1 bg-gradient-to-r from-accent via-amber-400 to-accent"></div>
     </div>
     <div class="px-6 sm:px-8 py-7">
+      <%# Admin-only jump to the audit of the values this submission overwrote —
+          shown only when it actually overwrote something. %>
+      <% submission_changes = FormSubmissionChanges.new(@form_submission) %>
+      <% if allowed_to?(:changes?, @form_submission) && submission_changes.edited? %>
+        <%= link_to changes_form_submission_path(@form_submission),
+                    class: "group mb-5 flex items-center gap-2 rounded-md border border-blue-200 bg-blue-50 px-3 py-2 text-sm font-semibold text-blue-900 hover:bg-blue-100" do %>
+          <i class="fa-solid fa-circle-info text-blue-500"></i>
+          What this submission changed
+          <span class="rounded-full bg-blue-200 px-1.5 text-2xs"><%= submission_changes.edited_count %></span>
+          <span class="ml-1 rounded-full bg-white/70 text-blue-700 px-1.5 py-0.5 text-2xs font-normal border border-blue-200"><i class="fa-solid fa-lock text-2xs mr-0.5"></i>admin</span>
+          <i class="fa-solid fa-arrow-right text-xs ml-auto text-blue-400 transition-transform group-hover:translate-x-0.5"></i>
+        <% end %>
+      <% end %>
       <%= render "form_submissions/submission", submission: @form_submission %>
 
       <% if event && @form_submission.role == "bulk_payment" %>

config/routes.rb

@@ -150,7 +150,9 @@
       patch :update_sections
     end
   end
-  resources :form_submissions, only: [ :index, :show ]
+  resources :form_submissions, only: [ :index, :show ] do
+    member { get :changes }
+  end
   resources :grants
   resources :scholarships, only: [ :index, :new, :create, :show, :edit, :update, :destroy ] do
     member do