Add support to Document::gotoNamedDest method.

Patch implements the Document's API gotoNamedDest, which is
part of the PDF specification [1], page 129, with the following
(short) description:

"Use this method to go to a named destination within the
PDF document".

[1] http://partners.adobe.com/public/developer/en/acrobat/sdk/5186AcroJS.pdf

"Named destination" is a common concept in the PDF world.
It can be used together with PDF's Links, Annotations, Bookmarks
and OpenActions, as well as an action per se, in case "this.gotoNamedDest"
is called directly.

Note that the implementation makes use of the existing hook
CPDFDoc_Environment::FFI_DoGoToAction, which ends up calling
out the embedder to actually handle it.
In case of Chromium, for instance, it calls PDFiumEngine::Form_DoGoToAction
which only handles for now the "page" property of the "destination".
Other properties, including zoom level, and scroll position
are ignored for the moment.

BUG=pdfium:492

Review-Url: https://codereview.chromium.org/2221823003

2 files changed, 54 insertions, 0 deletions

diff --git a/fpdfsdk/javascript/Document.cpp b/fpdfsdk/javascript/Document.cpp
index 161a5d09e9..8175fba697 100644
--- a/fpdfsdk/javascript/Document.cpp
+++ b/fpdfsdk/javascript/Document.cpp
@@ -10,9 +10,11 @@
 
 #include "core/fpdfapi/fpdf_font/include/cpdf_font.h"
 #include "core/fpdfapi/fpdf_page/include/cpdf_page.h"
+#include "core/fpdfapi/fpdf_parser/include/cpdf_array.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_document.h"
 #include "core/fpdfapi/fpdf_parser/include/fpdf_parser_decode.h"
 #include "core/fpdfdoc/include/cpdf_interform.h"
+#include "core/fpdfdoc/include/cpdf_nametree.h"
 #include "fpdfsdk/include/fsdk_mgr.h"
 #include "fpdfsdk/javascript/Field.h"
 #include "fpdfsdk/javascript/Icon.h"
@@ -124,6 +126,7 @@ JS_STATIC_METHOD_ENTRY(getPageNthWordQuads)
 JS_STATIC_METHOD_ENTRY(getPageNumWords)
 JS_STATIC_METHOD_ENTRY(getPrintParams)
 JS_STATIC_METHOD_ENTRY(getURL)
+JS_STATIC_METHOD_ENTRY(gotoNamedDest)
 JS_STATIC_METHOD_ENTRY(importAnFDF)
 JS_STATIC_METHOD_ENTRY(importAnXFDF)
 JS_STATIC_METHOD_ENTRY(importTextData)
@@ -1466,6 +1469,52 @@ FX_BOOL Document::getURL(IJS_Context* cc,
   return TRUE;
 }
 
+FX_BOOL Document::gotoNamedDest(IJS_Context* cc,
+                                const std::vector<CJS_Value>& params,
+                                CJS_Value& vRet,
+                                CFX_WideString& sError) {
+  CJS_Context* context = (CJS_Context*)cc;
+  if (params.size() != 1) {
+    sError = JSGetStringFromID(context, IDS_STRING_JSPARAMERROR);
+    return FALSE;
+  }
+
+  CPDF_Document* pDocument = m_pDocument->GetPDFDocument();
+  if (!pDocument)
+    return FALSE;
+
+  CFX_WideString wideName = params[0].ToCFXWideString();
+  CFX_ByteString utf8Name = wideName.UTF8Encode();
+
+  CPDF_NameTree nameTree(pDocument, "Dests");
+  CPDF_Array* destArray = nameTree.LookupNamedDest(pDocument, utf8Name);
+  if (!destArray)
+    return FALSE;
+
+  CPDF_Dest dest(destArray);
+  const CPDF_Array* arrayObject = ToArray(dest.GetObject());
+
+  std::unique_ptr<float[]> scrollPositionArray;
+  int scrollPositionArraySize = 0;
+
+  if (arrayObject) {
+    scrollPositionArray.reset(new float[arrayObject->GetCount()]);
+    int j = 0;
+    for (size_t i = 2; i < arrayObject->GetCount(); i++)
+      scrollPositionArray[j++] = arrayObject->GetFloatAt(i);
+    scrollPositionArraySize = j;
+  }
+
+  CJS_Runtime* runtime = context->GetJSRuntime();
+  runtime->BeginBlock();
+  CPDFDoc_Environment* pApp = m_pDocument->GetEnv();
+  pApp->FFI_DoGoToAction(dest.GetPageIndex(pDocument), dest.GetZoomMode(),
+                         scrollPositionArray.get(), scrollPositionArraySize);
+  runtime->EndBlock();
+
+  return TRUE;
+}
+
 void Document::AddDelayData(CJS_DelayData* pData) {
   m_DelayData.push_back(std::unique_ptr<CJS_DelayData>(pData));
 }
diff --git a/fpdfsdk/javascript/Document.h b/fpdfsdk/javascript/Document.h
index ae2d6c1afe..873f70e327 100644
--- a/fpdfsdk/javascript/Document.h
+++ b/fpdfsdk/javascript/Document.h
@@ -207,6 +207,10 @@ class Document : public CJS_EmbedObj {
                  const std::vector<CJS_Value>& params,
                  CJS_Value& vRet,
                  CFX_WideString& sError);
+  FX_BOOL gotoNamedDest(IJS_Context* cc,
+                        const std::vector<CJS_Value>& params,
+                        CJS_Value& vRet,
+                        CFX_WideString& sError);
   FX_BOOL importAnFDF(IJS_Context* cc,
                       const std::vector<CJS_Value>& params,
                       CJS_Value& vRet,
@@ -356,6 +360,7 @@ class CJS_Document : public CJS_Object {
   JS_STATIC_METHOD(getPageNumWords, Document);
   JS_STATIC_METHOD(getPrintParams, Document);
   JS_STATIC_METHOD(getURL, Document);
+  JS_STATIC_METHOD(gotoNamedDest, Document);
   JS_STATIC_METHOD(importAnFDF, Document);
   JS_STATIC_METHOD(importAnXFDF, Document);
   JS_STATIC_METHOD(importTextData, Document);