/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_image_encoders_png_nsPNGEncoder_h
#define mozilla_image_encoders_png_nsPNGEncoder_h

#include <png.h>

#include "imgIEncoder.h"
#include "nsCOMPtr.h"

#include "mozilla/Attributes.h"
#include "mozilla/ReentrantMonitor.h"

#define NS_PNGENCODER_CID                            \
  { /* 38d1592e-b81e-432b-86f8-471878bbfe07 */       \
    0x38d1592e, 0xb81e, 0x432b, {                    \
      0x86, 0xf8, 0x47, 0x18, 0x78, 0xbb, 0xfe, 0x07 \
    }                                                \
  }

// Provides PNG encoding functionality. Use InitFromData() to do the
// encoding. See that function definition for encoding options.

class nsPNGEncoder final : public imgIEncoder {
  typedef mozilla::ReentrantMonitor ReentrantMonitor;

 public:
  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_IMGIENCODER
  NS_DECL_NSIINPUTSTREAM
  NS_DECL_NSIASYNCINPUTSTREAM

  nsPNGEncoder();

 protected:
  ~nsPNGEncoder();
  nsresult ParseOptions(const nsAString& aOptions, bool* useTransparency,
                        bool* skipFirstFrame, uint32_t* numAnimatedFrames,
                        uint32_t* numIterations, uint32_t* frameDispose,
                        uint32_t* frameBlend, uint32_t* frameDelay,
                        uint32_t* offsetX, uint32_t* offsetY);
  void ConvertHostARGBRow(const uint8_t* aSrc, uint8_t* aDest,
                          uint32_t aPixelWidth, bool aUseTransparency);
  void StripAlpha(const uint8_t* aSrc, uint8_t* aDest, uint32_t aPixelWidth);
  static void WarningCallback(png_structp png_ptr, png_const_charp warning_msg);
  static void ErrorCallback(png_structp png_ptr, png_const_charp error_msg);
  static void WriteCallback(png_structp png, png_bytep data, png_size_t size);
  void NullOutImageBuffer();
  void NotifyListener();

  png_struct* mPNG;
  png_info* mPNGinfo;

  bool mIsAnimation;
  bool mFinished;

  // image buffer
  uint8_t* mImageBuffer;
  uint32_t mImageBufferSize;
  uint32_t mImageBufferUsed;

  uint32_t mImageBufferReadPoint;

  nsCOMPtr<nsIInputStreamCallback> mCallback;
  nsCOMPtr<nsIEventTarget> mCallbackTarget;
  uint32_t mNotifyThreshold;

  // nsPNGEncoder is designed to allow one thread to pump data into it while
  // another reads from it.  We lock to ensure that the buffer remains
  // append-only while we read from it (that it is not realloced) and to
  // ensure that only one thread dispatches a callback for each call to
  // AsyncWait.
  ReentrantMonitor mReentrantMonitor;
};
#endif  // mozilla_image_encoders_png_nsPNGEncoder_h