/*
 * upb - a minimalist implementation of protocol buffers.
 *
 * Copyright (c) 2014 Google Inc.  See LICENSE for details.
 * Author: Josh Haberman <jhaberman@gmail.com>
 *
 * upb::json::TypedPrinter allows you to create handlers that emit JSON
 * according to a specific protobuf schema.
 */

#ifndef UPB_JSON_TYPED_PRINTER_H_
#define UPB_JSON_TYPED_PRINTER_H_

#include "upb/sink.h"

#ifdef __cplusplus
namespace upb {
namespace json {
class TypedPrinter;
}  // namespace json
}  // namespace upb

typedef upb::json::TypedPrinter upb_json_typedprinter;
#else
struct upb_json_typedprinter;
typedef struct upb_json_typedprinter upb_json_typedprinter;
#endif


/* upb::json::TypedPrinter ****************************************************/

#ifdef __cplusplus

// Prints an incoming stream of data to a BytesSink in JSON format.
class upb::json::TypedPrinter {
 public:
  TypedPrinter(const upb::Handlers* handlers);
  ~TypedPrinter();

  // Resets the state of the printer, so that it will expect to begin a new
  // document.
  void Reset();

  // Resets the output pointer which will serve as our closure.  Implies
  // Reset().
  void ResetOutput(BytesSink* output);

  // The input to the printer.
  Sink* input();

  // Returns handlers for printing according to the specified schema.
  static reffed_ptr<const Handlers> NewHandlers(const upb::MessageDef* md);

 private:
#else
struct upb_json_typedprinter {
#endif
  upb_sink input_;
  // Pointer to yajl_gen; void* here so we don't have to include YAJL headers.
  void *yajl_gen_;
  void *subc_;
  upb_bytessink *output_;
  // We track the depth so that we know when to emit startstr/endstr on the
  // output.
  int depth_;
};

// Native C API.
#ifdef __cplusplus
extern "C" {
#endif

void upb_json_typedprinter_init(upb_json_typedprinter *p,
                                const upb_handlers *h);
void upb_json_typedprinter_uninit(upb_json_typedprinter *p);
void upb_json_typedprinter_reset(upb_json_typedprinter *p);
void upb_json_typedprinter_resetoutput(upb_json_typedprinter *p,
                                       upb_bytessink *output);
upb_sink *upb_json_typedprinter_input(upb_json_typedprinter *p);
const upb_handlers *upb_json_typedprinter_newhandlers(const upb_msgdef *md,
                                                      const void *owner);

#ifdef __cplusplus
}  // extern "C"
#endif

#ifdef __cplusplus

namespace upb {
namespace json {
inline TypedPrinter::TypedPrinter(const upb::Handlers* handlers) {
  upb_json_typedprinter_init(this, handlers);
}
inline TypedPrinter::~TypedPrinter() {
  upb_json_typedprinter_uninit(this);
}
inline void TypedPrinter::Reset() {
  upb_json_typedprinter_reset(this);
}
inline void TypedPrinter::ResetOutput(BytesSink* output) {
  upb_json_typedprinter_resetoutput(this, output);
}
inline Sink* TypedPrinter::input() {
  return upb_json_typedprinter_input(this);
}
inline reffed_ptr<const Handlers> TypedPrinter::NewHandlers(
    const upb::MessageDef *md) {
  const Handlers* h = upb_json_typedprinter_newhandlers(md, &h);
  return reffed_ptr<const Handlers>(h, &h);
}
}  // namespace json
}  // namespace upb

#endif

#endif  // UPB_JSON_TYPED_PRINTER_H_