merge preview docs

app/controllers/api/submission_documents_controller.rb

@@ -5,43 +5,71 @@ module Api
     load_and_authorize_resource :submission
 
     def index
+      is_merge = params[:merge] == 'true' &&
+                 (@submission.schema_documents || @submission.template.schema_documents).size > 1
+
       documents =
         if @submission.submitters.all?(&:completed_at?)
-          last_submitter = @submission.submitters.max_by(&:completed_at)
+          build_completed_documents(@submission, merge: is_merge)
+        else
+          build_preview_documents(@submission, merge: is_merge)
+        end
 
-          if last_submitter.documents_attachments.blank?
-            last_submitter.documents_attachments = Submissions::EnsureResultGenerated.call(last_submitter)
+      ActiveRecord::Associations::Preloader.new(records: documents, associations: [:blob]).call
+
+      expires_at = Accounts.link_expires_at(current_account)
+
+      render json: {
+        id: @submission.id,
+        documents: documents.map do |attachment|
+          { name: attachment.filename.base, url: ActiveStorage::Blob.proxy_url(attachment.blob, expires_at:) }
+        end
+      }
     end
 
-          last_submitter.documents_attachments
-        else
-          values_hash = Submissions::GeneratePreviewAttachments.build_values_hash(@submission)
+    private
 
-          if @submission.preview_documents.present? &&
-             @submission.preview_documents.all? { |s| s.metadata['values_hash'] == values_hash }
-            @submission.preview_documents
+    def build_completed_documents(submission, merge: false)
+      last_submitter = submission.submitters.max_by(&:completed_at)
+
+      if merge
+        if submission.merged_document_attachment.blank?
+          submission.merged_document_attachment =
+            Submissions::GenerateCombinedAttachment.call(last_submitter, with_audit: false)
+        end
+
+        [submission.merged_document_attachment]
       else
-            ApplicationRecord.no_touching do
-              @submission.preview_documents.each(&:destroy)
+        if last_submitter.documents_attachments.blank?
+          last_submitter.documents_attachments = Submissions::EnsureResultGenerated.call(last_submitter)
         end
 
-            Submissions::GeneratePreviewAttachments.call(@submission, values_hash:)
+        last_submitter.documents_attachments
       end
     end
 
-      ActiveRecord::Associations::Preloader.new(
-        records: documents,
-        associations: [:blob]
-      ).call
+    def build_preview_documents(submission, merge: false)
+      values_hash = Submissions::GeneratePreviewAttachments.build_values_hash(submission)
 
-      expires_at = Accounts.link_expires_at(current_account)
+      if merge
+        if submission.preview_merged_document_attachment.present? &&
+           submission.preview_merged_document_attachment.metadata['values_hash'] == values_hash
+          [submission.preview_merged_document_attachment]
+        else
+          ApplicationRecord.no_touching { submission.preview_merged_document_attachment&.destroy }
 
-      render json: {
-        id: @submission.id,
-        documents: documents.map do |attachment|
-          { name: attachment.filename.base, url: ActiveStorage::Blob.proxy_url(attachment.blob, expires_at:) }
+          Submissions::GeneratePreviewAttachments.call(submission, values_hash:, merge: true)
+        end
+      elsif submission.preview_documents.present? &&
+            submission.preview_documents.all? { |s| s.metadata['values_hash'] == values_hash }
+        submission.preview_documents
+      else
+        ApplicationRecord.no_touching do
+          submission.preview_documents.each(&:destroy)
+        end
+
+        Submissions::GeneratePreviewAttachments.call(submission, values_hash:)
       end
-      }
     end
   end
 end

app/models/submission.rb

@@ -63,6 +63,8 @@ class Submission < ApplicationRecord
 
   has_one_attached :audit_trail
   has_one_attached :combined_document
+  has_one_attached :merged_document
+  has_one_attached :preview_merged_document
 
   has_many_attached :preview_documents
   has_many_attached :documents

lib/submissions/generate_combined_attachment.rb

@@ -4,8 +4,8 @@ module Submissions
   module GenerateCombinedAttachment
     module_function
 
-    def call(submitter)
-      pdf = build_combined_pdf(submitter)
+    def call(submitter, with_audit: true)
+      pdf = build_combined_pdf(submitter, with_audit:)
 
       submission = submitter.submission
       account = submission.account
@@ -39,7 +39,7 @@ module Submissions
         blob: ActiveStorage::Blob.create_and_upload!(
           io: io.tap(&:rewind), filename: "#{submission.name || submission.template.name}.pdf"
         ),
-        name: 'combined_document',
+        name: with_audit ? 'combined_document' : 'merged_document',
         record: submission
       )
     end
@@ -58,14 +58,16 @@ module Submissions
       pdf.sign(io, write_options: { validate: false }, **sign_params)
     end
 
-    def build_combined_pdf(submitter)
+    def build_combined_pdf(submitter, with_audit:)
       pdfs_index = Submissions::GenerateResultAttachments.generate_pdfs(submitter)
 
+      if with_audit
         audit_trail = I18n.with_locale(submitter.account.locale) do
           Submissions::GenerateAuditTrail.build_audit_trail(submitter.submission)
         end
 
         audit_trail.dispatch_message(:complete_objects)
+      end
 
       result = HexaPDF::Document.new
 
@@ -79,7 +81,7 @@ module Submissions
         pdf.pages.each { |page| result.pages << result.import(page) }
       end
 
-      audit_trail.pages.each { |page| result.pages << result.import(page) }
+      audit_trail&.pages&.each { |page| result.pages << result.import(page) }
 
       result
     end

lib/submissions/generate_preview_attachments.rb

@@ -5,7 +5,7 @@ module Submissions
     module_function
 
     # rubocop:disable Metrics
-    def call(submission, values_hash: nil, submitter: nil)
+    def call(submission, values_hash: nil, submitter: nil, merge: false)
       values_hash ||= if submitter
                         build_submitter_values_hash(submitter)
                       else
@@ -42,6 +42,31 @@ module Submissions
 
       template = submission.template
 
+      if merge
+        result = HexaPDF::Document.new
+
+        (submission.template_schema || template.schema).each do |item|
+          pdf = pdfs_index[item['attachment_uuid']]
+
+          next unless pdf
+
+          pdf.dispatch_message(:complete_objects)
+
+          pdf.pages.each { |page| result.pages << result.import(page) }
+        end
+
+        attachment = build_pdf_attachment(
+          pdf: result,
+          submission:,
+          values_hash:,
+          name: 'preview_merged_document',
+          filename: "#{submission.name || template.name}.pdf"
+        )
+
+        ApplicationRecord.no_touching { attachment.save! }
+
+        [attachment]
+      else
         image_pdfs = []
         original_documents = submission.schema_documents.preload(:blob)
 
@@ -60,7 +85,7 @@ module Submissions
             build_pdf_attachment(pdf:, submission:, submitter:,
                                  uuid: item['attachment_uuid'],
                                  values_hash:,
-                               name: item['name'])
+                                 filename: "#{item['name']}.pdf")
           end
 
         return ApplicationRecord.no_touching { result_attachments.map { |e| e.tap(&:save!) } } if image_pdfs.size < 2
@@ -79,13 +104,14 @@ module Submissions
             submitter:,
             uuid: GenerateResultAttachments.images_pdf_uuid(original_documents.select(&:image?)),
             values_hash:,
-          name: submission.name || template.name
+            filename: "#{submission.name || template.name}.pdf"
           )
 
         ApplicationRecord.no_touching do
           (result_attachments + [images_pdf_attachment]).map { |e| e.tap(&:save!) }
         end
       end
+    end
 
     def build_values_hash(submission)
       Digest::MD5.hexdigest(
@@ -102,7 +128,8 @@ module Submissions
       )
     end
 
-    def build_pdf_attachment(pdf:, submission:, submitter:, uuid:, name:, values_hash:)
+    def build_pdf_attachment(pdf:, submission:, filename:, values_hash:, submitter: nil, uuid: nil,
+                             name: 'preview_documents')
       io = StringIO.new
 
       begin
@@ -114,13 +141,13 @@ module Submissions
       end
 
       ActiveStorage::Attachment.new(
-        blob: ActiveStorage::Blob.create_and_upload!(io: io.tap(&:rewind), filename: "#{name}.pdf"),
+        blob: ActiveStorage::Blob.create_and_upload!(io: io.tap(&:rewind), filename:),
         io_data: io.string,
         metadata: { original_uuid: uuid,
                     values_hash:,
                     analyzed: true,
-                    sha256: Base64.urlsafe_encode64(Digest::SHA256.digest(io.string)) },
-        name: 'preview_documents',
+                    sha256: Base64.urlsafe_encode64(Digest::SHA256.digest(io.string)) }.compact,
+        name: name,
         record: submitter || submission
       )
     end