refactor CPDF_Font and subclasses

Get rid of types; use virutal functions instead of type based checking;
remove unused functions; change casts; simplify load()/UnicodeFromCharCode()/CharCodeFromUnicode() calling.

R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1729823004 .

3 files changed, 12 insertions, 12 deletions

diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page.cpp
index d589d5809f..f05c4bea92 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page.cpp
@@ -71,17 +71,17 @@ void CPDF_TextObject::GetItemInfo(int index, CPDF_TextObjectItem* pInfo) const {
     return;
   }
   CPDF_Font* pFont = m_TextState.GetFont();
-  if (pFont->GetFontType() != PDFFONT_CIDFONT) {
+  if (!pFont->IsCIDFont()) {
     return;
   }
-  if (!((CPDF_CIDFont*)pFont)->IsVertWriting()) {
+  if (!pFont->AsCIDFont()->IsVertWriting()) {
     return;
   }
-  FX_WORD CID = ((CPDF_CIDFont*)pFont)->CIDFromCharCode(pInfo->m_CharCode);
+  FX_WORD CID = pFont->AsCIDFont()->CIDFromCharCode(pInfo->m_CharCode);
   pInfo->m_OriginY = pInfo->m_OriginX;
   pInfo->m_OriginX = 0;
   short vx, vy;
-  ((CPDF_CIDFont*)pFont)->GetVertOrigin(CID, vx, vy);
+  pFont->AsCIDFont()->GetVertOrigin(CID, vx, vy);
   FX_FLOAT fontsize = m_TextState.GetFontSize();
   pInfo->m_OriginX -= fontsize * vx / 1000;
   pInfo->m_OriginY -= fontsize * vy / 1000;
@@ -214,7 +214,7 @@ FX_FLOAT CPDF_TextObject::GetCharWidth(FX_DWORD charcode) const {
   FX_FLOAT fontsize = m_TextState.GetFontSize() / 1000;
   CPDF_Font* pFont = m_TextState.GetFont();
   FX_BOOL bVertWriting = FALSE;
-  CPDF_CIDFont* pCIDFont = pFont->GetCIDFont();
+  CPDF_CIDFont* pCIDFont = pFont->AsCIDFont();
   if (pCIDFont) {
     bVertWriting = pCIDFont->IsVertWriting();
   }
@@ -236,7 +236,7 @@ void CPDF_TextObject::CalcPositionData(FX_FLOAT* pTextAdvanceX,
   FX_FLOAT max_y = -10000 * 1.0f;
   CPDF_Font* pFont = m_TextState.GetFont();
   FX_BOOL bVertWriting = FALSE;
-  CPDF_CIDFont* pCIDFont = pFont->GetCIDFont();
+  CPDF_CIDFont* pCIDFont = pFont->AsCIDFont();
   if (pCIDFont) {
     bVertWriting = pCIDFont->IsVertWriting();
   }
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp
index 756e08646a..85b026f8e8 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp
@@ -261,12 +261,12 @@ CPDF_Font* CPDF_DocPageData::GetStandardFont(const CFX_ByteStringC& fontName,
       continue;
     if (pFont->IsEmbedded())
       continue;
-    if (pFont->GetFontType() != PDFFONT_TYPE1)
+    if (!pFont->IsType1Font())
       continue;
     if (pFont->GetFontDict()->KeyExist("Widths"))
       continue;
 
-    CPDF_Type1Font* pT1Font = pFont->GetType1Font();
+    CPDF_Type1Font* pT1Font = pFont->AsType1Font();
     if (pEncoding && !pT1Font->GetEncoding()->IsIdentical(pEncoding))
       continue;
 
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp
index 3018630463..465c74a425 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp
@@ -1258,9 +1258,9 @@ CPDF_Font* CPDF_StreamContentParser::FindFont(const CFX_ByteString& name) {
   }
 
   CPDF_Font* pFont = m_pDocument->LoadFont(pFontDict);
-  if (pFont && pFont->GetType3Font()) {
-    pFont->GetType3Font()->SetPageResources(m_pResources);
-    pFont->GetType3Font()->CheckType3FontMetrics();
+  if (pFont && pFont->IsType3Font()) {
+    pFont->AsType3Font()->SetPageResources(m_pResources);
+    pFont->AsType3Font()->CheckType3FontMetrics();
   }
   return pFont;
 }
@@ -1336,7 +1336,7 @@ void CPDF_StreamContentParser::AddTextObject(CFX_ByteString* pStrs,
     return;
   }
   int textmode;
-  if (pFont->GetFontType() == PDFFONT_TYPE3) {
+  if (pFont->IsType3Font()) {
     textmode = 0;
   } else {
     textmode = m_pCurStates->m_TextState.GetObject()->m_TextMode;