Add public APIs for undo / redo in forms.

Add FORM_CanUndo(), FORM_CanRedo(), FORM_Undo(), and FORM_Redo().

BUG=chromium:764260

Change-Id: I1d9ea67152d9b35d9b8e1d7ef7d019706fdfa30a
Reviewed-on: https://pdfium-review.googlesource.com/30872
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 36 insertions, 0 deletions

diff --git a/fpdfsdk/cpdfsdk_pageview.cpp b/fpdfsdk/cpdfsdk_pageview.cpp
index b7f8cdfe10..b68828b144 100644
--- a/fpdfsdk/cpdfsdk_pageview.cpp
+++ b/fpdfsdk/cpdfsdk_pageview.cpp
@@ -268,6 +268,42 @@ void CPDFSDK_PageView::ReplaceSelection(const WideString& text) {
   }
 }
 
+bool CPDFSDK_PageView::CanUndo() {
+  if (CPDFSDK_Annot* pAnnot = GetFocusAnnot()) {
+    CPDFSDK_AnnotHandlerMgr* pAnnotHandlerMgr =
+        m_pFormFillEnv->GetAnnotHandlerMgr();
+    return pAnnotHandlerMgr->Annot_CanUndo(pAnnot);
+  }
+  return false;
+}
+
+bool CPDFSDK_PageView::CanRedo() {
+  if (CPDFSDK_Annot* pAnnot = GetFocusAnnot()) {
+    CPDFSDK_AnnotHandlerMgr* pAnnotHandlerMgr =
+        m_pFormFillEnv->GetAnnotHandlerMgr();
+    return pAnnotHandlerMgr->Annot_CanRedo(pAnnot);
+  }
+  return false;
+}
+
+bool CPDFSDK_PageView::Undo() {
+  if (CPDFSDK_Annot* pAnnot = GetFocusAnnot()) {
+    CPDFSDK_AnnotHandlerMgr* pAnnotHandlerMgr =
+        m_pFormFillEnv->GetAnnotHandlerMgr();
+    return pAnnotHandlerMgr->Annot_Undo(pAnnot);
+  }
+  return false;
+}
+
+bool CPDFSDK_PageView::Redo() {
+  if (CPDFSDK_Annot* pAnnot = GetFocusAnnot()) {
+    CPDFSDK_AnnotHandlerMgr* pAnnotHandlerMgr =
+        m_pFormFillEnv->GetAnnotHandlerMgr();
+    return pAnnotHandlerMgr->Annot_Redo(pAnnot);
+  }
+  return false;
+}
+
 bool CPDFSDK_PageView::OnFocus(const CFX_PointF& point, uint32_t nFlag) {
   CPDFSDK_Annot::ObservedPtr pAnnot(GetFXWidgetAtPoint(point));
   if (!pAnnot) {