Save extracted text for searchified PDFs.

If a PDF is searchified, the extracted text is written to the file when
the PDF is saved.
This is done behind `chrome_pdf::features::kPdfSearchifySave` flag which
is disabled by default.
In a next CL (http://crrev.com/c/6110470), the user will be given the
option to save the original PDF or the PDF with extracted text.

Bug: 382610226
Change-Id: I73e1028ce60211e8bed165ffaff7f6630c9103c4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6049156
Reviewed-by: Andy Phan <andyphan@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Alan Screen <awscreen@chromium.org>
Commit-Queue: Ramin Halavati <rhalavati@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1407724}

chrome/browser/resources/pdf/constants.ts

@@ -88,6 +88,7 @@ export enum SaveRequestType {
   ANNOTATION,
   ORIGINAL,
   EDITED,
+  SEARCHIFIED,  // Saves the PDF with extracted text.
 }
 
 export interface Point {

chrome/browser/resources/pdf/metrics.ts

@@ -261,7 +261,11 @@ export enum UserAction {
   OPEN_INK2_BOTTOM_TOOLBAR_FIRST = 97,
   OPEN_INK2_BOTTOM_TOOLBAR = 98,
 
-  NUMBER_OF_ACTIONS = 99,
+  // Recorded when the user triggers a save of the searchified document.
+  SAVE_SEARCHIFIED_FIRST = 99,
+  SAVE_SEARCHIFIED = 100,
+
+  NUMBER_OF_ACTIONS = 101,
 }
 
 function createFirstMap(): Map<UserAction, UserAction> {

chrome/browser/resources/pdf/pdf_viewer.ts

@@ -1155,6 +1155,8 @@ export class PdfViewerElement extends PdfViewerBaseElement {
       saveMode = SaveRequestType.ANNOTATION;
     } else if (this.hasEdits_) {
       saveMode = SaveRequestType.EDITED;
+    } else if (this.hasSearchifyText_) {
+      saveMode = SaveRequestType.SEARCHIFIED;
     } else {
       saveMode = SaveRequestType.ORIGINAL;
     }
@@ -1292,6 +1294,11 @@ export class PdfViewerElement extends PdfViewerBaseElement {
   private async save_(requestType: SaveRequestType) {
     this.recordSaveMetrics_(requestType);
 
+    // TODO(crbug.com/382610226): Update for `SaveRequestType.SEARCHIFIED` to
+    // allow users to select saving original PDF or text extracted one.
+    // To do so, the save type should be asked first, and then content would be
+    // fetched based on the selected type.
+
     // If we have entered annotation mode we must require the local
     // contents to ensure annotations are saved, unless the user specifically
     // requested the original document. Otherwise we would save the cached
@@ -1436,6 +1443,12 @@ export class PdfViewerElement extends PdfViewerBaseElement {
       case SaveRequestType.EDITED:
         record(UserAction.SAVE_EDITED);
         break;
+      case SaveRequestType.SEARCHIFIED:
+        // TODO(crbug.com/382610226): Update metric after the code is updated to
+        // give users the option to save searchified or original PDF, and add
+        // test.
+        record(UserAction.SAVE_SEARCHIFIED);
+        break;
     }
   }
 

pdf/pdf_view_web_plugin.cc

@@ -1499,6 +1499,9 @@ void PdfViewWebPlugin::OnHasSearchifyText() {
   message.Set("type", "setHasSearchifyText");
   client_->PostMessage(std::move(message));
   pdf_accessibility_data_handler_->OnHasSearchifyText();
+  if (chrome_pdf::features::IsPdfSearchifySaveEnabled()) {
+    SetPluginCanSave(true);
+  }
 }
 #endif  // BUILDFLAG(ENABLE_SCREEN_AI_SERVICE)
 
@@ -1778,6 +1781,18 @@ void PdfViewWebPlugin::HandleSaveMessage(const base::Value::Dict& message) {
     case SaveRequestType::kEdited:
       SaveToBuffer(request_type, token);
       return;
+    case SaveRequestType::kSearchified:
+#if BUILDFLAG(ENABLE_SCREEN_AI_SERVICE)
+      CHECK(chrome_pdf::features::IsPdfSearchifySaveEnabled());
+      // TODO(crbug.com/382610226): If engine has searchified text, ensure all
+      // pages are searchified and then save.
+      SaveToBuffer(request_type, token);
+      return;
+#else
+      // PDF Searchify is not expected to be triggered when ScreenAI service is
+      // not enabled.
+      NOTREACHED();
+#endif
   }
   NOTREACHED();
 }
@@ -1947,7 +1962,8 @@ void PdfViewWebPlugin::HandleViewportMessage(const base::Value::Dict& message) {
 void PdfViewWebPlugin::SaveToBuffer(SaveRequestType request_type,
                                     const std::string& token) {
   CHECK(request_type == SaveRequestType::kAnnotation ||
-        request_type == SaveRequestType::kEdited);
+        request_type == SaveRequestType::kEdited ||
+        request_type == SaveRequestType::kSearchified);
 
   engine_->KillFormFocus();
 
@@ -1966,6 +1982,10 @@ void PdfViewWebPlugin::SaveToBuffer(SaveRequestType request_type,
   use_save_data |= !!ink_module_;
 #endif  // BUILDFLAG(ENABLE_PDF_INK2)
 
+#if BUILDFLAG(ENABLE_SCREEN_AI_SERVICE)
+  use_save_data |= (request_type == SaveRequestType::kSearchified);
+#endif
+
   if (use_save_data) {
     base::Value::BlobStorage data = engine_->GetSaveData();
     if (IsSaveDataSizeValid(data.size())) {

pdf/pdf_view_web_plugin.h

@@ -113,6 +113,7 @@ class PdfViewWebPlugin final : public PDFiumEngineClient,
     kAnnotation = 0,
     kOriginal = 1,
     kEdited = 2,
+    kSearchified = 3,
   };
 
   // Provides services from the plugin's container.

tools/metrics/histograms/metadata/pdf/enums.xml

@@ -126,6 +126,8 @@ chromium-metrics-reviews@google.com.
   <int value="96" label="OpenInk2SidePanel"/>
   <int value="97" label="OpenInk2BottomToolbarFirst"/>
   <int value="98" label="OpenInk2BottomToolbar"/>
+  <int value="99" label="SaveSearchifiedFirst"/>
+  <int value="100" label="SaveSearchified"/>
 </enum>
 
 <enum name="ChromePDFViewerLoadStatus">