Add type cast definitions for CPDF_Array.

This Cl adds ToArray, CPDF_Object::AsArray and CPDF_Object::IsArray and
updates the src to use them as needed.

BUG=pdfium:201
R=thestig@chromium.org, tsepez@chromium.org

Review URL: https://codereview.chromium.org/1417893003 .

9 files changed, 169 insertions, 235 deletions

diff --git a/core/src/fpdfdoc/doc_action.cpp b/core/src/fpdfdoc/doc_action.cpp
index bcbfe0f112..d685f64cae 100644
--- a/core/src/fpdfdoc/doc_action.cpp
+++ b/core/src/fpdfdoc/doc_action.cpp
@@ -22,9 +22,8 @@ CPDF_Dest CPDF_Action::GetDest(CPDF_Document* pDoc) const {
     CFX_ByteStringC name = pDest->GetString();
     return CPDF_Dest(name_tree.LookupNamedDest(pDoc, name));
   }
-  if (pDest->GetType() == PDFOBJ_ARRAY) {
-    return CPDF_Dest((CPDF_Array*)pDest);
-  }
+  if (CPDF_Array* pArray = pDest->AsArray())
+    return CPDF_Dest(pArray);
   return CPDF_Dest();
 }
 const FX_CHAR* g_sATypes[] = {
@@ -108,8 +107,8 @@ FX_DWORD CPDF_ActionFields::GetFieldsCount() const {
     return 1;
   if (pFields->IsString())
     return 1;
-  if (pFields->GetType() == PDFOBJ_ARRAY)
-    return ((CPDF_Array*)pFields)->GetCount();
+  if (CPDF_Array* pArray = pFields->AsArray())
+    return pArray->GetCount();
   return 0;
 }
 void CPDF_ActionFields::GetAllFields(CFX_PtrArray& fieldObjects) const {
@@ -133,8 +132,7 @@ void CPDF_ActionFields::GetAllFields(CFX_PtrArray& fieldObjects) const {
 
   if (pFields->IsDictionary() || pFields->IsString()) {
     fieldObjects.Add(pFields);
-  } else if (pFields->GetType() == PDFOBJ_ARRAY) {
-    CPDF_Array* pArray = (CPDF_Array*)pFields;
+  } else if (CPDF_Array* pArray = pFields->AsArray()) {
     FX_DWORD iCount = pArray->GetCount();
     for (FX_DWORD i = 0; i < iCount; i++) {
       CPDF_Object* pObj = pArray->GetElementValue(i);
@@ -166,8 +164,8 @@ CPDF_Object* CPDF_ActionFields::GetField(FX_DWORD iIndex) const {
   if (pFields->IsDictionary() || pFields->IsString()) {
     if (iIndex == 0)
       pFindObj = pFields;
-  } else if (pFields->GetType() == PDFOBJ_ARRAY) {
-    pFindObj = ((CPDF_Array*)pFields)->GetElementValue(iIndex);
+  } else if (CPDF_Array* pArray = pFields->AsArray()) {
+    pFindObj = pArray->GetElementValue(iIndex);
   }
   return pFindObj;
 }
@@ -222,20 +220,16 @@ int32_t CPDF_Action::GetOperationType() const {
   return 0;
 }
 FX_DWORD CPDF_Action::GetSubActionsCount() const {
-  if (m_pDict == NULL || !m_pDict->KeyExist("Next")) {
+  if (!m_pDict || !m_pDict->KeyExist("Next"))
     return 0;
-  }
+
   CPDF_Object* pNext = m_pDict->GetElementValue("Next");
-  if (!pNext) {
+  if (!pNext)
     return 0;
-  }
-  int iObjType = pNext->GetType();
-  if (iObjType == PDFOBJ_DICTIONARY) {
+  if (pNext->IsDictionary())
     return 1;
-  }
-  if (iObjType == PDFOBJ_ARRAY) {
-    return ((CPDF_Array*)pNext)->GetCount();
-  }
+  if (CPDF_Array* pArray = pNext->AsArray())
+    return pArray->GetCount();
   return 0;
 }
 CPDF_Action CPDF_Action::GetSubAction(FX_DWORD iIndex) const {
@@ -246,8 +240,7 @@ CPDF_Action CPDF_Action::GetSubAction(FX_DWORD iIndex) const {
   if (CPDF_Dictionary* pDict = ToDictionary(pNext)) {
     if (iIndex == 0)
       return CPDF_Action(pDict);
-  } else if (pNext->GetType() == PDFOBJ_ARRAY) {
-    CPDF_Array* pArray = static_cast<CPDF_Array*>(pNext);
+  } else if (CPDF_Array* pArray = ToArray(pNext)) {
     return CPDF_Action(pArray->GetDict(iIndex));
   }
   return CPDF_Action();
diff --git a/core/src/fpdfdoc/doc_ap.cpp b/core/src/fpdfdoc/doc_ap.cpp
index 71025ec532..77a1f15306 100644
--- a/core/src/fpdfdoc/doc_ap.cpp
+++ b/core/src/fpdfdoc/doc_ap.cpp
@@ -618,12 +618,11 @@ static FX_BOOL GenerateWidgetAP(CPDF_Document* pDoc,
           }
           if (CPDF_Object* pOpt = pOpts->GetElementValue(i)) {
             CFX_WideString swItem;
-            if (pOpt->IsString()) {
+            if (pOpt->IsString())
               swItem = pOpt->GetUnicodeText();
-            } else if (pOpt->GetType() == PDFOBJ_ARRAY) {
-              swItem =
-                  ((CPDF_Array*)pOpt)->GetElementValue(1)->GetUnicodeText();
-            }
+            else if (CPDF_Array* pArray = pOpt->AsArray())
+              swItem = pArray->GetElementValue(1)->GetUnicodeText();
+
             FX_BOOL bSelected = FALSE;
             if (pSels) {
               for (FX_DWORD s = 0, ssz = pSels->GetCount(); s < ssz; s++) {
diff --git a/core/src/fpdfdoc/doc_basic.cpp b/core/src/fpdfdoc/doc_basic.cpp
index cbf956bd9b..b32e34bb4c 100644
--- a/core/src/fpdfdoc/doc_basic.cpp
+++ b/core/src/fpdfdoc/doc_basic.cpp
@@ -7,10 +7,11 @@
 #include "../../include/fpdfdoc/fpdf_doc.h"
 const int nMaxRecursion = 32;
 int CPDF_Dest::GetPageIndex(CPDF_Document* pDoc) {
-  if (m_pObj == NULL || m_pObj->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = ToArray(m_pObj);
+  if (!pArray)
     return 0;
-  }
-  CPDF_Object* pPage = ((CPDF_Array*)m_pObj)->GetElementValue(0);
+
+  CPDF_Object* pPage = pArray->GetElementValue(0);
   if (!pPage)
     return 0;
   if (pPage->IsNumber())
@@ -20,10 +21,11 @@ int CPDF_Dest::GetPageIndex(CPDF_Document* pDoc) {
   return pDoc->GetPageIndex(pPage->GetObjNum());
 }
 FX_DWORD CPDF_Dest::GetPageObjNum() {
-  if (m_pObj == NULL || m_pObj->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = ToArray(m_pObj);
+  if (!pArray)
     return 0;
-  }
-  CPDF_Object* pPage = ((CPDF_Array*)m_pObj)->GetElementValue(0);
+
+  CPDF_Object* pPage = pArray->GetElementValue(0);
   if (!pPage)
     return 0;
   if (pPage->IsNumber())
@@ -35,11 +37,12 @@ FX_DWORD CPDF_Dest::GetPageObjNum() {
 const FX_CHAR* g_sZoomModes[] = {"XYZ",  "Fit",   "FitH",  "FitV", "FitR",
                                  "FitB", "FitBH", "FitBV", ""};
 int CPDF_Dest::GetZoomMode() {
-  if (m_pObj == NULL || m_pObj->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = ToArray(m_pObj);
+  if (!pArray)
     return 0;
-  }
+
   CFX_ByteString mode;
-  CPDF_Object* pObj = ((CPDF_Array*)m_pObj)->GetElementValue(1);
+  CPDF_Object* pObj = pArray->GetElementValue(1);
   mode = pObj ? pObj->GetString() : CFX_ByteString();
   int i = 0;
   while (g_sZoomModes[i][0] != '\0') {
@@ -51,16 +54,11 @@ int CPDF_Dest::GetZoomMode() {
   return 0;
 }
 FX_FLOAT CPDF_Dest::GetParam(int index) {
-  if (m_pObj == NULL || m_pObj->GetType() != PDFOBJ_ARRAY) {
-    return 0;
-  }
-  return ((CPDF_Array*)m_pObj)->GetNumber(2 + index);
+  CPDF_Array* pArray = ToArray(m_pObj);
+  return pArray ? pArray->GetNumber(2 + index) : 0;
 }
 CFX_ByteString CPDF_Dest::GetRemoteName() {
-  if (m_pObj == NULL) {
-    return CFX_ByteString();
-  }
-  return m_pObj->GetString();
+  return m_pObj ? m_pObj->GetString() : CFX_ByteString();
 }
 CPDF_NameTree::CPDF_NameTree(CPDF_Document* pDoc,
                              const CFX_ByteStringC& category) {
@@ -224,23 +222,19 @@ CPDF_Object* CPDF_NameTree::LookupValue(const CFX_ByteString& csName) const {
 CPDF_Array* CPDF_NameTree::LookupNamedDest(CPDF_Document* pDoc,
                                            const CFX_ByteStringC& sName) {
   CPDF_Object* pValue = LookupValue(sName);
-  if (pValue == NULL) {
+  if (!pValue) {
     CPDF_Dictionary* pDests = pDoc->GetRoot()->GetDict(FX_BSTRC("Dests"));
-    if (pDests == NULL) {
-      return NULL;
-    }
+    if (!pDests)
+      return nullptr;
     pValue = pDests->GetElementValue(sName);
   }
-  if (pValue == NULL) {
-    return NULL;
-  }
-  if (pValue->GetType() == PDFOBJ_ARRAY) {
-    return (CPDF_Array*)pValue;
-  }
-  if (CPDF_Dictionary* pDict = pValue->AsDictionary()) {
+  if (!pValue)
+    return nullptr;
+  if (CPDF_Array* pArray = pValue->AsArray())
+    return pArray;
+  if (CPDF_Dictionary* pDict = pValue->AsDictionary())
     return pDict->GetArray(FX_BSTRC("D"));
-  }
-  return NULL;
+  return nullptr;
 }
 #if _FXM_PLATFORM_ == _FXM_PLATFORM_APPLE_ || \
     _FXM_PLATFORM_ == _FXM_PLATFORM_WINDOWS_
diff --git a/core/src/fpdfdoc/doc_bookmark.cpp b/core/src/fpdfdoc/doc_bookmark.cpp
index 6b020e5957..5ebd27e6e7 100644
--- a/core/src/fpdfdoc/doc_bookmark.cpp
+++ b/core/src/fpdfdoc/doc_bookmark.cpp
@@ -68,21 +68,19 @@ CFX_WideString CPDF_Bookmark::GetTitle() const {
   return CFX_WideString(buf.get(), len);
 }
 CPDF_Dest CPDF_Bookmark::GetDest(CPDF_Document* pDocument) const {
-  if (!m_pDict) {
+  if (!m_pDict)
     return CPDF_Dest();
-  }
+
   CPDF_Object* pDest = m_pDict->GetElementValue("Dest");
   if (!pDest)
     return CPDF_Dest();
-
   if (pDest->IsString() || pDest->IsName()) {
     CPDF_NameTree name_tree(pDocument, FX_BSTRC("Dests"));
     CFX_ByteStringC name = pDest->GetString();
     return CPDF_Dest(name_tree.LookupNamedDest(pDocument, name));
   }
-  if (pDest->GetType() == PDFOBJ_ARRAY) {
-    return CPDF_Dest((CPDF_Array*)pDest);
-  }
+  if (CPDF_Array* pArray = pDest->AsArray())
+    return CPDF_Dest(pArray);
   return CPDF_Dest();
 }
 CPDF_Action CPDF_Bookmark::GetAction() const {
diff --git a/core/src/fpdfdoc/doc_formcontrol.cpp b/core/src/fpdfdoc/doc_formcontrol.cpp
index c5f47d20cb..35329f9e05 100644
--- a/core/src/fpdfdoc/doc_formcontrol.cpp
+++ b/core/src/fpdfdoc/doc_formcontrol.cpp
@@ -85,15 +85,13 @@ CFX_ByteString CPDF_FormControl::GetCheckedAPState() {
   CFX_ByteString csOn = GetOnStateName();
   if (GetType() == CPDF_FormField::RadioButton ||
       GetType() == CPDF_FormField::CheckBox) {
-    CPDF_Object* pOpt = FPDF_GetFieldAttr(m_pField->m_pDict, "Opt");
-    if (pOpt != NULL && pOpt->GetType() == PDFOBJ_ARRAY) {
+    if (ToArray(FPDF_GetFieldAttr(m_pField->m_pDict, "Opt"))) {
       int iIndex = m_pField->GetControlIndex(this);
       csOn.Format("%d", iIndex);
     }
   }
-  if (csOn.IsEmpty()) {
+  if (csOn.IsEmpty())
     csOn = "Yes";
-  }
   return csOn;
 }
 CFX_WideString CPDF_FormControl::GetExportValue() {
@@ -102,10 +100,10 @@ CFX_WideString CPDF_FormControl::GetExportValue() {
   CFX_ByteString csOn = GetOnStateName();
   if (GetType() == CPDF_FormField::RadioButton ||
       GetType() == CPDF_FormField::CheckBox) {
-    CPDF_Object* pOpt = FPDF_GetFieldAttr(m_pField->m_pDict, "Opt");
-    if (pOpt != NULL && pOpt->GetType() == PDFOBJ_ARRAY) {
+    if (CPDF_Array* pArray =
+            ToArray(FPDF_GetFieldAttr(m_pField->m_pDict, "Opt"))) {
       int iIndex = m_pField->GetControlIndex(this);
-      csOn = ((CPDF_Array*)pOpt)->GetString(iIndex);
+      csOn = pArray->GetString(iIndex);
     }
   }
   if (csOn.IsEmpty()) {
diff --git a/core/src/fpdfdoc/doc_formfield.cpp b/core/src/fpdfdoc/doc_formfield.cpp
index f9b8438a0e..51465727ee 100644
--- a/core/src/fpdfdoc/doc_formfield.cpp
+++ b/core/src/fpdfdoc/doc_formfield.cpp
@@ -307,10 +307,9 @@ CFX_WideString CPDF_FormField::GetValue(FX_BOOL bDefault) {
     case PDFOBJ_STREAM:
       return pValue->GetUnicodeText();
     case PDFOBJ_ARRAY:
-      pValue = ((CPDF_Array*)pValue)->GetElementValue(0);
-      if (pValue) {
+      pValue = pValue->AsArray()->GetElementValue(0);
+      if (pValue)
         return pValue->GetUnicodeText();
-      }
       break;
   }
   return CFX_WideString();
@@ -419,28 +418,24 @@ int CPDF_FormField::GetMaxLen() {
 }
 int CPDF_FormField::CountSelectedItems() {
   CPDF_Object* pValue = FPDF_GetFieldAttr(m_pDict, "V");
-  if (pValue == NULL) {
+  if (!pValue) {
     pValue = FPDF_GetFieldAttr(m_pDict, "I");
-    if (pValue == NULL) {
+    if (!pValue)
       return 0;
-    }
   }
 
   if (pValue->IsString() || pValue->IsNumber())
     return pValue->GetString().IsEmpty() ? 0 : 1;
-
-  if (pValue->GetType() != PDFOBJ_ARRAY) {
-    return 0;
-  }
-  return ((CPDF_Array*)pValue)->GetCount();
+  if (CPDF_Array* pArray = pValue->AsArray())
+    return pArray->GetCount();
+  return 0;
 }
 int CPDF_FormField::GetSelectedIndex(int index) {
   CPDF_Object* pValue = FPDF_GetFieldAttr(m_pDict, "V");
-  if (pValue == NULL) {
+  if (!pValue) {
     pValue = FPDF_GetFieldAttr(m_pDict, "I");
-    if (pValue == NULL) {
+    if (!pValue)
       return -1;
-    }
   }
   if (pValue->IsNumber())
     return pValue->GetInteger();
@@ -449,16 +444,13 @@ int CPDF_FormField::GetSelectedIndex(int index) {
   if (pValue->IsString()) {
     if (index != 0)
       return -1;
-
     sel_value = pValue->GetUnicodeText();
   } else {
-    if (pValue->GetType() != PDFOBJ_ARRAY) {
-      return -1;
-    }
-    if (index < 0) {
+    CPDF_Array* pArray = pValue->AsArray();
+    if (!pArray || index < 0)
       return -1;
-    }
-    CPDF_Object* elementValue = ((CPDF_Array*)pValue)->GetElementValue(index);
+
+    CPDF_Object* elementValue = pArray->GetElementValue(index);
     sel_value =
         elementValue ? elementValue->GetUnicodeText() : CFX_WideString();
   }
@@ -537,10 +529,10 @@ FX_BOOL CPDF_FormField::IsItemSelected(int index) {
     return (pValue->GetInteger() == index);
   }
 
-  if (pValue->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = pValue->AsArray();
+  if (!pArray)
     return FALSE;
-  }
-  CPDF_Array* pArray = (CPDF_Array*)pValue;
+
   int iPos = -1;
   for (int j = 0; j < CountSelectedOptions(); j++) {
     if (GetSelectedOptionIndex(j) == index) {
@@ -584,11 +576,8 @@ FX_BOOL CPDF_FormField::SetItemSelection(int index,
           if (pValue->GetUnicodeText() == opt_value) {
             m_pDict->RemoveAt("V");
           }
-        } else if (pValue->GetType() == PDFOBJ_ARRAY) {
+        } else if (pValue->IsArray()) {
           CPDF_Array* pArray = CPDF_Array::Create();
-          if (pArray == NULL) {
-            return FALSE;
-          }
           int iCount = CountOptions();
           for (int i = 0; i < iCount; i++) {
             if (i != index) {
@@ -703,24 +692,19 @@ void CPDF_FormField::UpdateAP(CPDF_FormControl* pControl) {
   }
 }
 int CPDF_FormField::CountOptions() {
-  CPDF_Object* pValue = FPDF_GetFieldAttr(m_pDict, "Opt");
-  if (pValue == NULL || pValue->GetType() != PDFOBJ_ARRAY) {
-    return 0;
-  }
-  return ((CPDF_Array*)pValue)->GetCount();
+  CPDF_Array* pArray = ToArray(FPDF_GetFieldAttr(m_pDict, "Opt"));
+  return pArray ? pArray->GetCount() : 0;
 }
 CFX_WideString CPDF_FormField::GetOptionText(int index, int sub_index) {
-  CPDF_Object* pValue = FPDF_GetFieldAttr(m_pDict, "Opt");
-  if (pValue == NULL || pValue->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = ToArray(FPDF_GetFieldAttr(m_pDict, "Opt"));
+  if (!pArray)
     return CFX_WideString();
-  }
-  CPDF_Object* pOption = ((CPDF_Array*)pValue)->GetElementValue(index);
-  if (pOption == NULL) {
+
+  CPDF_Object* pOption = pArray->GetElementValue(index);
+  if (!pOption)
     return CFX_WideString();
-  }
-  if (pOption->GetType() == PDFOBJ_ARRAY) {
-    pOption = ((CPDF_Array*)pOption)->GetElementValue(sub_index);
-  }
+  if (CPDF_Array* pOptionArray = pOption->AsArray())
+    pOption = pOptionArray->GetElementValue(sub_index);
 
   CPDF_String* pString = ToString(pOption);
   return pString ? pString->GetUnicodeText() : CFX_WideString();
@@ -796,7 +780,7 @@ FX_BOOL CPDF_FormField::CheckControl(int iControlIndex,
     }
   }
   CPDF_Object* pOpt = FPDF_GetFieldAttr(m_pDict, "Opt");
-  if (pOpt == NULL || pOpt->GetType() != PDFOBJ_ARRAY) {
+  if (!ToArray(pOpt)) {
     if (bChecked) {
       m_pDict->SetAtName("V", csBExport);
     } else {
diff --git a/core/src/fpdfdoc/doc_link.cpp b/core/src/fpdfdoc/doc_link.cpp
index 977efeafd1..6d3f6c5046 100644
--- a/core/src/fpdfdoc/doc_link.cpp
+++ b/core/src/fpdfdoc/doc_link.cpp
@@ -81,9 +81,8 @@ CPDF_Dest CPDF_Link::GetDest(CPDF_Document* pDoc) {
     CFX_ByteStringC name = pDest->GetString();
     return CPDF_Dest(name_tree.LookupNamedDest(pDoc, name));
   }
-  if (pDest->GetType() == PDFOBJ_ARRAY) {
-    return CPDF_Dest((CPDF_Array*)pDest);
-  }
+  if (CPDF_Array* pArray = pDest->AsArray())
+    return CPDF_Dest(pArray);
   return CPDF_Dest();
 }
 CPDF_Action CPDF_Link::GetAction() {
diff --git a/core/src/fpdfdoc/doc_ocg.cpp b/core/src/fpdfdoc/doc_ocg.cpp
index e66b04489f..b252456df6 100644
--- a/core/src/fpdfdoc/doc_ocg.cpp
+++ b/core/src/fpdfdoc/doc_ocg.cpp
@@ -7,23 +7,18 @@
 #include "../../include/fpdfdoc/fpdf_doc.h"
 static int32_t FPDFDOC_OCG_FindGroup(const CPDF_Object* pObject,
                                      const CPDF_Dictionary* pGroupDict) {
-  if (pObject == NULL || pGroupDict == NULL) {
+  if (!pObject || !pGroupDict)
     return -1;
-  }
-  int32_t iType = pObject->GetType();
-  if (iType == PDFOBJ_ARRAY) {
-    FX_DWORD dwCount = ((CPDF_Array*)pObject)->GetCount();
+
+  if (const CPDF_Array* pArray = pObject->AsArray()) {
+    FX_DWORD dwCount = pArray->GetCount();
     for (FX_DWORD i = 0; i < dwCount; i++) {
-      if (((CPDF_Array*)pObject)->GetDict(i) == pGroupDict) {
+      if (pArray->GetDict(i) == pGroupDict)
         return i;
-      }
     }
     return -1;
   }
-  if (pObject->GetDict() == pGroupDict) {
-    return 0;
-  }
-  return -1;
+  return pObject->GetDict() == pGroupDict ? 0 : -1;
 }
 static FX_BOOL FPDFDOC_OCG_HasIntent(
     const CPDF_Dictionary* pDict,
@@ -35,13 +30,12 @@ static FX_BOOL FPDFDOC_OCG_HasIntent(
     return csElement == csDef;
   }
   CFX_ByteString bsIntent;
-  if (pIntent->GetType() == PDFOBJ_ARRAY) {
-    FX_DWORD dwCount = ((CPDF_Array*)pIntent)->GetCount();
+  if (CPDF_Array* pArray = pIntent->AsArray()) {
+    FX_DWORD dwCount = pArray->GetCount();
     for (FX_DWORD i = 0; i < dwCount; i++) {
-      bsIntent = ((CPDF_Array*)pIntent)->GetString(i);
-      if (bsIntent == FX_BSTRC("All") || bsIntent == csElement) {
+      bsIntent = pArray->GetString(i);
+      if (bsIntent == FX_BSTRC("All") || bsIntent == csElement)
         return TRUE;
-      }
     }
     return FALSE;
   }
@@ -206,15 +200,12 @@ FX_BOOL CPDF_OCContext::GetOCGVE(CPDF_Array* pExpression,
   CFX_ByteString csOperator = pExpression->GetString(0);
   if (csOperator == FX_BSTRC("Not")) {
     pOCGObj = pExpression->GetElementValue(1);
-    if (pOCGObj == NULL) {
+    if (!pOCGObj)
       return FALSE;
-    }
-    if (CPDF_Dictionary* pDict = pOCGObj->AsDictionary()) {
+    if (CPDF_Dictionary* pDict = pOCGObj->AsDictionary())
       return !(bFromConfig ? LoadOCGState(pDict) : GetOCGVisible(pDict));
-    }
-    if (pOCGObj->GetType() == PDFOBJ_ARRAY) {
-      return !GetOCGVE((CPDF_Array*)pOCGObj, bFromConfig, nLevel + 1);
-    }
+    if (CPDF_Array* pArray = pOCGObj->AsArray())
+      return !GetOCGVE(pArray, bFromConfig, nLevel + 1);
     return FALSE;
   }
   if (csOperator == FX_BSTRC("Or") || csOperator == FX_BSTRC("And")) {
@@ -225,11 +216,11 @@ FX_BOOL CPDF_OCContext::GetOCGVE(CPDF_Array* pExpression,
         continue;
       }
       FX_BOOL bItem = FALSE;
-      if (CPDF_Dictionary* pDict = pOCGObj->AsDictionary()) {
+      if (CPDF_Dictionary* pDict = pOCGObj->AsDictionary())
         bItem = bFromConfig ? LoadOCGState(pDict) : GetOCGVisible(pDict);
-      } else if (pOCGObj->GetType() == PDFOBJ_ARRAY) {
-        bItem = GetOCGVE((CPDF_Array*)pOCGObj, bFromConfig, nLevel + 1);
-      }
+      else if (CPDF_Array* pArray = pOCGObj->AsArray())
+        bItem = GetOCGVE(pArray, bFromConfig, nLevel + 1);
+
       if (i == 1) {
         bValue = bItem;
       } else {
@@ -253,38 +244,32 @@ FX_BOOL CPDF_OCContext::LoadOCMDState(const CPDF_Dictionary* pOCMDDict,
   }
   CFX_ByteString csP = pOCMDDict->GetString(FX_BSTRC("P"), FX_BSTRC("AnyOn"));
   CPDF_Object* pOCGObj = pOCMDDict->GetElementValue(FX_BSTRC("OCGs"));
-  if (pOCGObj == NULL) {
+  if (!pOCGObj)
     return TRUE;
-  }
-  if (const CPDF_Dictionary* pDict = pOCGObj->AsDictionary()) {
+  if (const CPDF_Dictionary* pDict = pOCGObj->AsDictionary())
     return bFromConfig ? LoadOCGState(pDict) : GetOCGVisible(pDict);
-  }
-  if (pOCGObj->GetType() != PDFOBJ_ARRAY) {
+
+  CPDF_Array* pArray = pOCGObj->AsArray();
+  if (!pArray)
     return TRUE;
-  }
+
   FX_BOOL bState = FALSE;
   if (csP == FX_BSTRC("AllOn") || csP == FX_BSTRC("AllOff")) {
     bState = TRUE;
   }
-  int32_t iCount = ((CPDF_Array*)pOCGObj)->GetCount();
+  int32_t iCount = pArray->GetCount();
   for (int32_t i = 0; i < iCount; i++) {
     FX_BOOL bItem = TRUE;
-    CPDF_Dictionary* pItemDict = ((CPDF_Array*)pOCGObj)->GetDict(i);
-    if (pItemDict) {
+    CPDF_Dictionary* pItemDict = pArray->GetDict(i);
+    if (pItemDict)
       bItem = bFromConfig ? LoadOCGState(pItemDict) : GetOCGVisible(pItemDict);
-    }
-    if (csP == FX_BSTRC("AnyOn") && bItem) {
-      return TRUE;
-    }
-    if (csP == FX_BSTRC("AnyOff") && !bItem) {
+
+    if ((csP == FX_BSTRC("AnyOn") && bItem) ||
+        (csP == FX_BSTRC("AnyOff") && !bItem))
       return TRUE;
-    }
-    if (csP == FX_BSTRC("AllOn") && !bItem) {
+    if ((csP == FX_BSTRC("AllOn") && !bItem) ||
+        (csP == FX_BSTRC("AllOff") && bItem))
       return FALSE;
-    }
-    if (csP == FX_BSTRC("AllOff") && bItem) {
-      return FALSE;
-    }
   }
   return bState;
 }
diff --git a/core/src/fpdfdoc/doc_tagged.cpp b/core/src/fpdfdoc/doc_tagged.cpp
index ac29d90118..2b20e07bb8 100644
--- a/core/src/fpdfdoc/doc_tagged.cpp
+++ b/core/src/fpdfdoc/doc_tagged.cpp
@@ -46,48 +46,47 @@ CPDF_StructTreeImpl::~CPDF_StructTreeImpl() {
     }
 }
 void CPDF_StructTreeImpl::LoadDocTree() {
-  m_pPage = NULL;
-  if (m_pTreeRoot == NULL) {
+  m_pPage = nullptr;
+  if (!m_pTreeRoot)
     return;
-  }
+
   CPDF_Object* pKids = m_pTreeRoot->GetElementValue(FX_BSTRC("K"));
-  if (pKids == NULL) {
+  if (!pKids)
     return;
-  }
   if (CPDF_Dictionary* pDict = pKids->AsDictionary()) {
     CPDF_StructElementImpl* pStructElementImpl =
-        new CPDF_StructElementImpl(this, NULL, pDict);
+        new CPDF_StructElementImpl(this, nullptr, pDict);
     m_Kids.Add(pStructElementImpl);
     return;
   }
-  if (pKids->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = pKids->AsArray();
+  if (!pArray)
     return;
-  }
-  CPDF_Array* pArray = (CPDF_Array*)pKids;
+
   for (FX_DWORD i = 0; i < pArray->GetCount(); i++) {
     CPDF_Dictionary* pKid = pArray->GetDict(i);
     CPDF_StructElementImpl* pStructElementImpl =
-        new CPDF_StructElementImpl(this, NULL, pKid);
+        new CPDF_StructElementImpl(this, nullptr, pKid);
     m_Kids.Add(pStructElementImpl);
   }
 }
 void CPDF_StructTreeImpl::LoadPageTree(const CPDF_Dictionary* pPageDict) {
   m_pPage = pPageDict;
-  if (m_pTreeRoot == NULL) {
+  if (!m_pTreeRoot)
     return;
-  }
+
   CPDF_Object* pKids = m_pTreeRoot->GetElementValue(FX_BSTRC("K"));
-  if (pKids == NULL) {
+  if (!pKids)
     return;
-  }
+
   FX_DWORD dwKids = 0;
-  if (pKids->IsDictionary()) {
+  if (pKids->IsDictionary())
     dwKids = 1;
-  } else if (pKids->GetType() == PDFOBJ_ARRAY) {
-    dwKids = ((CPDF_Array*)pKids)->GetCount();
-  } else {
+  else if (CPDF_Array* pArray = pKids->AsArray())
+    dwKids = pArray->GetCount();
+  else
     return;
-  }
+
   FX_DWORD i;
   m_Kids.SetSize(dwKids);
   for (i = 0; i < dwKids; i++) {
@@ -101,11 +100,10 @@ void CPDF_StructTreeImpl::LoadPageTree(const CPDF_Dictionary* pPageDict) {
   CPDF_NumberTree parent_tree(pParentTree);
   int parents_id = pPageDict->GetInteger(FX_BSTRC("StructParents"), -1);
   if (parents_id >= 0) {
-    CPDF_Object* pParents = parent_tree.LookupValue(parents_id);
-    if (pParents == NULL || pParents->GetType() != PDFOBJ_ARRAY) {
+    CPDF_Array* pParentArray = ToArray(parent_tree.LookupValue(parents_id));
+    if (!pParentArray)
       return;
-    }
-    CPDF_Array* pParentArray = (CPDF_Array*)pParents;
+
     for (i = 0; i < pParentArray->GetCount(); i++) {
       CPDF_Dictionary* pParent = pParentArray->GetDict(i);
       if (pParent == NULL) {
@@ -171,27 +169,23 @@ FX_BOOL CPDF_StructTreeImpl::AddTopLevelNode(CPDF_Dictionary* pDict,
       return FALSE;
     }
   }
-  if (pObj->GetType() == PDFOBJ_ARRAY) {
-    CPDF_Array* pTopKids = (CPDF_Array*)pObj;
+  if (CPDF_Array* pTopKids = pObj->AsArray()) {
     FX_DWORD i;
     FX_BOOL bSave = FALSE;
     for (i = 0; i < pTopKids->GetCount(); i++) {
       CPDF_Object* pKidRef = pTopKids->GetElement(i);
-      if (pKidRef == NULL || pKidRef->GetType() != PDFOBJ_REFERENCE) {
+      if (!pKidRef || pKidRef->GetType() != PDFOBJ_REFERENCE)
         continue;
-      }
-      if (((CPDF_Reference*)pKidRef)->GetRefObjNum() != pDict->GetObjNum()) {
+      if (((CPDF_Reference*)pKidRef)->GetRefObjNum() != pDict->GetObjNum())
         continue;
-      }
-      if (m_Kids[i]) {
+
+      if (m_Kids[i])
         m_Kids[i]->Release();
-      }
       m_Kids[i] = pElement->Retain();
       bSave = TRUE;
     }
-    if (!bSave) {
+    if (!bSave)
       return FALSE;
-    }
   }
   return TRUE;
 }
@@ -231,15 +225,14 @@ void CPDF_StructElementImpl::Release() {
 void CPDF_StructElementImpl::LoadKids(CPDF_Dictionary* pDict) {
   CPDF_Object* pObj = pDict->GetElement(FX_BSTRC("Pg"));
   FX_DWORD PageObjNum = 0;
-  if (pObj && pObj->GetType() == PDFOBJ_REFERENCE) {
+  if (pObj && pObj->GetType() == PDFOBJ_REFERENCE)
     PageObjNum = ((CPDF_Reference*)pObj)->GetRefObjNum();
-  }
+
   CPDF_Object* pKids = pDict->GetElementValue(FX_BSTRC("K"));
-  if (pKids == NULL) {
+  if (!pKids)
     return;
-  }
-  if (pKids->GetType() == PDFOBJ_ARRAY) {
-    CPDF_Array* pArray = (CPDF_Array*)pKids;
+
+  if (CPDF_Array* pArray = pKids->AsArray()) {
     m_Kids.SetSize(pArray->GetCount());
     for (FX_DWORD i = 0; i < pArray->GetCount(); i++) {
       CPDF_Object* pKid = pArray->GetElementValue(i);
@@ -316,25 +309,22 @@ void CPDF_StructElementImpl::LoadKid(FX_DWORD PageObjNum,
 static CPDF_Dictionary* FindAttrDict(CPDF_Object* pAttrs,
                                      const CFX_ByteStringC& owner,
                                      FX_FLOAT nLevel = 0.0F) {
-  if (nLevel > nMaxRecursion) {
-    return NULL;
-  }
-  if (pAttrs == NULL) {
-    return NULL;
-  }
-  CPDF_Dictionary* pDict = NULL;
+  if (nLevel > nMaxRecursion)
+    return nullptr;
+  if (!pAttrs)
+    return nullptr;
+
+  CPDF_Dictionary* pDict = nullptr;
   if (pAttrs->IsDictionary()) {
     pDict = pAttrs->AsDictionary();
   } else if (pAttrs->GetType() == PDFOBJ_STREAM) {
     pDict = ((CPDF_Stream*)pAttrs)->GetDict();
-  } else if (pAttrs->GetType() == PDFOBJ_ARRAY) {
-    CPDF_Array* pArray = (CPDF_Array*)pAttrs;
+  } else if (CPDF_Array* pArray = pAttrs->AsArray()) {
     for (FX_DWORD i = 0; i < pArray->GetCount(); i++) {
       CPDF_Object* pElement = pArray->GetElementValue(i);
       pDict = FindAttrDict(pElement, owner, nLevel + 1);
-      if (pDict) {
+      if (pDict)
         return pDict;
-      }
     }
   }
   if (pDict && pDict->GetString(FX_BSTRC("O")) == owner) {
@@ -370,44 +360,40 @@ CPDF_Object* CPDF_StructElementImpl::GetAttr(const CFX_ByteStringC& owner,
     }
   }
   CPDF_Object* pC = m_pDict->GetElementValue(FX_BSTRC("C"));
-  if (pC == NULL) {
-    return NULL;
-  }
+  if (!pC)
+    return nullptr;
+
   CPDF_Dictionary* pClassMap =
       m_pTree->m_pTreeRoot->GetDict(FX_BSTRC("ClassMap"));
-  if (pClassMap == NULL) {
-    return NULL;
-  }
-  if (pC->GetType() == PDFOBJ_ARRAY) {
-    CPDF_Array* pArray = (CPDF_Array*)pC;
+  if (!pClassMap)
+    return nullptr;
+
+  if (CPDF_Array* pArray = pC->AsArray()) {
     for (FX_DWORD i = 0; i < pArray->GetCount(); i++) {
       CFX_ByteString class_name = pArray->GetString(i);
       CPDF_Dictionary* pClassDict = pClassMap->GetDict(class_name);
-      if (pClassDict && pClassDict->GetString(FX_BSTRC("O")) == owner) {
+      if (pClassDict && pClassDict->GetString(FX_BSTRC("O")) == owner)
         return pClassDict->GetElementValue(name);
-      }
     }
-    return NULL;
+    return nullptr;
   }
   CFX_ByteString class_name = pC->GetString();
   CPDF_Dictionary* pClassDict = pClassMap->GetDict(class_name);
-  if (pClassDict && pClassDict->GetString(FX_BSTRC("O")) == owner) {
+  if (pClassDict && pClassDict->GetString(FX_BSTRC("O")) == owner)
     return pClassDict->GetElementValue(name);
-  }
-  return NULL;
+  return nullptr;
 }
 CPDF_Object* CPDF_StructElementImpl::GetAttr(const CFX_ByteStringC& owner,
                                              const CFX_ByteStringC& name,
                                              FX_BOOL bInheritable,
                                              int subindex) {
   CPDF_Object* pAttr = GetAttr(owner, name, bInheritable);
-  if (pAttr == NULL || subindex == -1 || pAttr->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = ToArray(pAttr);
+  if (!pArray || subindex == -1)
     return pAttr;
-  }
-  CPDF_Array* pArray = (CPDF_Array*)pAttr;
-  if (subindex >= (int)pArray->GetCount()) {
+
+  if (subindex >= static_cast<int>(pArray->GetCount()))
     return pAttr;
-  }
   return pArray->GetElementValue(subindex);
 }
 CFX_ByteString CPDF_StructElementImpl::GetName(
@@ -427,11 +413,9 @@ FX_ARGB CPDF_StructElementImpl::GetColor(const CFX_ByteStringC& owner,
                                          FX_ARGB default_value,
                                          FX_BOOL bInheritable,
                                          int subindex) {
-  CPDF_Object* pAttr = GetAttr(owner, name, bInheritable, subindex);
-  if (pAttr == NULL || pAttr->GetType() != PDFOBJ_ARRAY) {
+  CPDF_Array* pArray = ToArray(GetAttr(owner, name, bInheritable, subindex));
+  if (!pArray)
     return default_value;
-  }
-  CPDF_Array* pArray = (CPDF_Array*)pAttr;
   return 0xff000000 | ((int)(pArray->GetNumber(0) * 255) << 16) |
          ((int)(pArray->GetNumber(1) * 255) << 8) |
          (int)(pArray->GetNumber(2) * 255);