Refactor modification of Contents in CPDF_PageContentGenerator.

This is a pure refactor, there should be no change in behavior. It
prepares for the next CL, which will allow modification of content
streams.

Bug: pdfium:1051
Change-Id: I01ca3e897efe423e89df75e1f31cd67539cc3d08
Reviewed-on: https://pdfium-review.googlesource.com/34470
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 38 insertions, 0 deletions

diff --git a/core/fpdfapi/edit/cpdf_pagecontentmanager.h b/core/fpdfapi/edit/cpdf_pagecontentmanager.h
new file mode 100644
index 0000000000..384405b188
--- /dev/null
+++ b/core/fpdfapi/edit/cpdf_pagecontentmanager.h
@@ -0,0 +1,38 @@
+// Copyright 2018 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.
+
+#ifndef CORE_FPDFAPI_EDIT_CPDF_PAGECONTENTMANAGER_H_
+#define CORE_FPDFAPI_EDIT_CPDF_PAGECONTENTMANAGER_H_
+
+#include <sstream>
+
+#include "core/fxcrt/unowned_ptr.h"
+
+class CPDF_Array;
+class CPDF_Document;
+class CPDF_Object;
+class CPDF_Stream;
+class CPDF_PageObjectHolder;
+
+class CPDF_PageContentManager {
+ public:
+  explicit CPDF_PageContentManager(CPDF_PageObjectHolder* pObjHolder);
+  ~CPDF_PageContentManager();
+
+  // Gets the Content stream at a given index. If Contents is a single stream
+  // rather than an array, it is considered to be at index 0.
+  CPDF_Stream* GetStreamByIndex(size_t stream_index);
+
+  // Adds a new Content stream. Its index in the array will be returned, or 0
+  // if Contents is not an array, but only a single stream.
+  size_t AddStream(std::ostringstream* buf);
+
+ private:
+  UnownedPtr<CPDF_PageObjectHolder> const obj_holder_;
+  UnownedPtr<CPDF_Document> const doc_;
+  UnownedPtr<CPDF_Array> contents_array_;
+  UnownedPtr<CPDF_Stream> contents_stream_;
+};
+
+#endif  // CORE_FPDFAPI_EDIT_CPDF_PAGECONTENTMANAGER_H_