Refactor TextField to have a base struct FormField

This CL refactors TextField struct to have a base struct FormField. This
change is needed so that other form fields can be populated in future.

Bug: 1030242
Change-Id: I4e6f45ca2bcb0e4a5e57de35622d12d29889c8c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2251615
Commit-Queue: Mansi Awasthi <maawas@microsoft.com>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Ankit Kumar 🌪️ <ankk@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#780853}

pdf/pdfium/pdfium_page.cc

@@ -1169,11 +1169,7 @@ void PDFiumPage::PopulateAnnotations() {
         break;
       }
       case FPDF_ANNOT_WIDGET: {
-        // TODO(crbug.com/1030242): Populate other types of form fields too.
-        if (FPDFAnnot_GetFormFieldType(engine_->form(), annot.get()) ==
-            FPDF_FORMFIELD_TEXTFIELD) {
-          PopulateTextField(annot.get());
-        }
+        PopulateFormField(annot.get());
         break;
       }
       default:
@@ -1234,23 +1230,48 @@ void PDFiumPage::PopulateTextField(FPDF_ANNOTATION annot) {
   DCHECK_EQ(FPDFAnnot_GetFormFieldType(form_handle, annot),
             FPDF_FORMFIELD_TEXTFIELD);
 
-  FS_RECTF rect;
-  if (!FPDFAnnot_GetRect(annot, &rect))
+  TextField text_field;
+  if (!PopulateFormFieldProperties(annot, &text_field))
     return;
 
-  TextField text_field;
-  // We use the bounding box of the text field as the bounding rect.
-  text_field.bounding_rect =
-      PageToScreen(pp::Point(), 1.0, rect.left, rect.top, rect.right,
-                   rect.bottom, PageOrientation::kOriginal);
   text_field.value = base::UTF16ToUTF8(CallPDFiumWideStringBufferApi(
       base::BindRepeating(&FPDFAnnot_GetFormFieldValue, form_handle, annot),
       /*check_expected_size=*/true));
-  text_field.name = base::UTF16ToUTF8(CallPDFiumWideStringBufferApi(
+  text_fields_.push_back(std::move(text_field));
+}
+
+void PDFiumPage::PopulateFormField(FPDF_ANNOTATION annot) {
+  DCHECK_EQ(FPDFAnnot_GetSubtype(annot), FPDF_ANNOT_WIDGET);
+  int form_field_type = FPDFAnnot_GetFormFieldType(engine_->form(), annot);
+
+  // TODO(crbug.com/1030242): Populate other types of form fields too.
+  switch (form_field_type) {
+    case FPDF_FORMFIELD_TEXTFIELD: {
+      PopulateTextField(annot);
+      break;
+    }
+    default:
+      break;
+  }
+}
+
+bool PDFiumPage::PopulateFormFieldProperties(FPDF_ANNOTATION annot,
+                                             FormField* form_field) {
+  DCHECK(annot);
+  FS_RECTF rect;
+  if (!FPDFAnnot_GetRect(annot, &rect))
+    return false;
+
+  // We use the bounding box of the form field as the bounding rect.
+  form_field->bounding_rect =
+      PageToScreen(pp::Point(), 1.0, rect.left, rect.top, rect.right,
+                   rect.bottom, PageOrientation::kOriginal);
+  FPDF_FORMHANDLE form_handle = engine_->form();
+  form_field->name = base::UTF16ToUTF8(CallPDFiumWideStringBufferApi(
       base::BindRepeating(&FPDFAnnot_GetFormFieldName, form_handle, annot),
       /*check_expected_size=*/true));
-  text_field.flags = FPDFAnnot_GetFormFieldFlags(form_handle, annot);
-  text_fields_.push_back(std::move(text_field));
+  form_field->flags = FPDFAnnot_GetFormFieldFlags(form_handle, annot);
+  return true;
 }
 
 bool PDFiumPage::GetUnderlyingTextRangeForRect(const pp::FloatRect& rect,
@@ -1382,6 +1403,12 @@ PDFiumPage::Highlight::Highlight(const Highlight& that) = default;
 
 PDFiumPage::Highlight::~Highlight() = default;
 
+PDFiumPage::FormField::FormField() = default;
+
+PDFiumPage::FormField::FormField(const FormField& that) = default;
+
+PDFiumPage::FormField::~FormField() = default;
+
 PDFiumPage::TextField::TextField() = default;
 
 PDFiumPage::TextField::TextField(const TextField& that) = default;

pdf/pdfium/pdfium_page.h

@@ -235,18 +235,26 @@ class PDFiumPage {
     std::string note_text;
   };
 
+  // Represents a form field within the page.
+  struct FormField {
+    FormField();
+    FormField(const FormField& other);
+    ~FormField();
+
+    pp::Rect bounding_rect;
+    // Represents the name of form field as defined in the field dictionary.
+    std::string name;
+    // Represents the flags of form field as defined in the field dictionary.
+    int flags;
+  };
+
   // Represents a text field within the page.
-  struct TextField {
+  struct TextField : FormField {
     TextField();
     TextField(const TextField& other);
     ~TextField();
 
-    // Represents the name of form field as defined in the field dictionary.
-    std::string name;
     std::string value;
-    pp::Rect bounding_rect;
-    // Represents the flags of form field as defined in the field dictionary.
-    int flags;
   };
 
   // Returns a link index if the given character index is over a link, or -1
@@ -266,6 +274,8 @@ class PDFiumPage {
   void PopulateHighlight(FPDF_ANNOTATION annot);
   // Populate |text_fields_| with |annot|.
   void PopulateTextField(FPDF_ANNOTATION annot);
+  // Populate form fields like text field on the page.
+  void PopulateFormField(FPDF_ANNOTATION annot);
   // Returns link type and fills target associated with a destination. Returns
   // NONSELECTABLE_AREA if detection failed.
   Area GetDestinationTarget(FPDF_DEST destination, LinkTarget* target);
@@ -305,6 +315,8 @@ class PDFiumPage {
   static uint32_t CountLinkHighlightOverlaps(
       const std::vector<Link>& links,
       const std::vector<Highlight>& highlights);
+  bool PopulateFormFieldProperties(FPDF_ANNOTATION annot,
+                                   FormField* form_field);
 
   PDFiumEngine* engine_;
   ScopedFPDFPage page_;