/* Copyright 2016 Google Inc. All Rights Reserved.

   Distributed under MIT license.

   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT

*/

/* Output buffer for WOFF2 decompression. */

#ifndef WOFF2_WOFF2_OUT_H_

#define WOFF2_WOFF2_OUT_H_

#include <algorithm>

#include <cstring>

#include <memory>

#include <string>

namespace woff2 {

// Suggested max size for output.

const size_t kDefaultMaxSize = 30 * 1024 * 1024;

/**

 * Output interface for the woff2 decoding.

 *

 * Writes to arbitrary offsets are supported to facilitate updating offset

 * table and checksums after tables are ready. Reading the current size is

 * supported so a 'loca' table can be built up while writing glyphs.

 *

 * By default limits size to kDefaultMaxSize.

 */

class WOFF2Out {

 public:

  virtual ~WOFF2Out(void) {}

  // Append n bytes of data from buf.

  // Return true if all written, false otherwise.

  virtual bool Write(const void *buf, size_t n) = 0;

  // Write n bytes of data from buf at offset.

  // Return true if all written, false otherwise.

  virtual bool Write(const void *buf, size_t offset, size_t n) = 0;

  virtual size_t Size() = 0;

};

/**

 * Expanding memory block for woff2 out. By default limited to kDefaultMaxSize.

 */

class WOFF2StringOut : public WOFF2Out {

 public:

  // Create a writer that writes its data to buf.

  // buf->size() will grow to at most max_size

  // buf may be sized (e.g. using EstimateWOFF2FinalSize) or empty.

  explicit WOFF2StringOut(std::string* buf);

  bool Write(const void *buf, size_t n) override;

  bool Write(const void *buf, size_t offset, size_t n) override;

  size_t Size() override { return offset_; }

  size_t MaxSize() { return max_size_; }

  void SetMaxSize(size_t max_size);

 private:

  std::string* buf_;

  size_t max_size_;

  size_t offset_;

};

/**

 * Fixed memory block for woff2 out.

 */

class WOFF2MemoryOut : public WOFF2Out {

 public:

  // Create a writer that writes its data to buf.

  WOFF2MemoryOut(uint8_t* buf, size_t buf_size);

  bool Write(const void *buf, size_t n) override;

  bool Write(const void *buf, size_t offset, size_t n) override;

  size_t Size() override { return offset_; }

 private:

  uint8_t* buf_;

  size_t buf_size_;

  size_t offset_;

};

} // namespace woff2

#endif  // WOFF2_WOFF2_OUT_H_