1 files changed, 136 insertions, 0 deletions
diff --git a/core/fpdfdoc/cpdf_pagelabel.cpp b/core/fpdfdoc/cpdf_pagelabel.cpp
new file mode 100644
index 0000000000..886e8448b2
--- /dev/null
+++ b/core/fpdfdoc/cpdf_pagelabel.cpp
@@ -0,0 +1,136 @@
+// Copyright 2016 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "core/fpdfdoc/cpdf_pagelabel.h"
+
+#include "core/fpdfapi/fpdf_parser/include/cpdf_dictionary.h"
+#include "core/fpdfapi/fpdf_parser/include/cpdf_document.h"
+#include "core/fpdfapi/fpdf_parser/include/fpdf_parser_decode.h"
+#include "core/fpdfdoc/doc_utils.h"
+
+namespace {
+
+CFX_WideString MakeRoman(int num) {
+  const int kArabic[] = {1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1};
+  const CFX_WideString kRoman[] = {L"m",  L"cm", L"d",  L"cd", L"c",
+                                   L"xc", L"l",  L"xl", L"x",  L"ix",
+                                   L"v",  L"iv", L"i"};
+  const int kMaxNum = 1000000;
+
+  num %= kMaxNum;
+  int i = 0;
+  CFX_WideString wsRomanNumber;
+  while (num > 0) {
+    while (num >= kArabic[i]) {
+      num = num - kArabic[i];
+      wsRomanNumber += kRoman[i];
+    }
+    i = i + 1;
+  }
+  return wsRomanNumber;
+}
+
+CFX_WideString MakeLetters(int num) {
+  if (num == 0)
+    return CFX_WideString();
+
+  CFX_WideString wsLetters;
+  const int nMaxCount = 1000;
+  const int nLetterCount = 26;
+  --num;
+
+  int count = num / nLetterCount + 1;
+  count %= nMaxCount;
+  FX_WCHAR ch = L'a' + num % nLetterCount;
+  for (int i = 0; i < count; i++)
+    wsLetters += ch;
+  return wsLetters;
+}
+
+CFX_WideString GetLabelNumPortion(int num, const CFX_ByteString& bsStyle) {
+  CFX_WideString wsNumPortion;
+  if (bsStyle.IsEmpty())
+    return wsNumPortion;
+  if (bsStyle == "D") {
+    wsNumPortion.Format(L"%d", num);
+  } else if (bsStyle == "R") {
+    wsNumPortion = MakeRoman(num);
+    wsNumPortion.MakeUpper();
+  } else if (bsStyle == "r") {
+    wsNumPortion = MakeRoman(num);
+  } else if (bsStyle == "A") {
+    wsNumPortion = MakeLetters(num);
+    wsNumPortion.MakeUpper();
+  } else if (bsStyle == "a") {
+    wsNumPortion = MakeLetters(num);
+  }
+  return wsNumPortion;
+}
+
+}  // namespace
+
+CPDF_PageLabel::CPDF_PageLabel(CPDF_Document* pDocument)
+    : m_pDocument(pDocument) {}
+
+CFX_WideString CPDF_PageLabel::GetLabel(int nPage) const {
+  CFX_WideString wsLabel;
+  if (!m_pDocument)
+    return wsLabel;
+
+  CPDF_Dictionary* pPDFRoot = m_pDocument->GetRoot();
+  if (!pPDFRoot)
+    return wsLabel;
+
+  CPDF_Dictionary* pLabels = pPDFRoot->GetDictBy("PageLabels");
+  CPDF_NumberTree numberTree(pLabels);
+  CPDF_Object* pValue = nullptr;
+  int n = nPage;
+  while (n >= 0) {
+    pValue = numberTree.LookupValue(n);
+    if (pValue)
+      break;
+    n--;
+  }
+
+  if (pValue) {
+    pValue = pValue->GetDirect();
+    if (CPDF_Dictionary* pLabel = pValue->AsDictionary()) {
+      if (pLabel->KeyExist("P"))
+        wsLabel += pLabel->GetUnicodeTextBy("P");
+
+      CFX_ByteString bsNumberingStyle = pLabel->GetStringBy("S", "");
+      int nLabelNum = nPage - n + pLabel->GetIntegerBy("St", 1);
+      CFX_WideString wsNumPortion =
+          GetLabelNumPortion(nLabelNum, bsNumberingStyle);
+      wsLabel += wsNumPortion;
+      return wsLabel;
+    }
+  }
+  wsLabel.Format(L"%d", nPage + 1);
+  return wsLabel;
+}
+
+int32_t CPDF_PageLabel::GetPageByLabel(const CFX_ByteStringC& bsLabel) const {
+  if (!m_pDocument)
+    return -1;
+
+  CPDF_Dictionary* pPDFRoot = m_pDocument->GetRoot();
+  if (!pPDFRoot)
+    return -1;
+
+  int nPages = m_pDocument->GetPageCount();
+  for (int i = 0; i < nPages; i++) {
+    if (PDF_EncodeText(GetLabel(i)).Compare(bsLabel))
+      return i;
+  }
+
+  int nPage = FXSYS_atoi(CFX_ByteString(bsLabel).c_str());  // NUL terminate.
+  return nPage > 0 && nPage <= nPages ? nPage : -1;
+}
+
+int32_t CPDF_PageLabel::GetPageByLabel(const CFX_WideStringC& wsLabel) const {
+  return GetPageByLabel(PDF_EncodeText(wsLabel.c_str()).AsStringC());
+}