osmfixer/src/util/json/Writer.cpp

// Copyright 2018, University of Freiburg,
// Chair of Algorithms and Data Structures.
// Authors: Patrick Brosi <brosi@informatik.uni-freiburg.de>

#include <iomanip>
#include "Writer.h"
#include "util/String.h"
using namespace util;
using namespace json;

using std::ostream;
using std::string;
using std::map;

// _____________________________________________________________________________
Writer::Writer(std::ostream* out)
    : _out(out), _pretty(false), _indent(2), _floatPrec(10) {}

// _____________________________________________________________________________
Writer::Writer(std::ostream* out, size_t prec)
    : _out(out), _pretty(false), _indent(2), _floatPrec(prec) {}

// _____________________________________________________________________________
Writer::Writer(std::ostream* out, size_t prec, bool pret)
    : _out(out), _pretty(pret), _indent(2), _floatPrec(prec) {}

// _____________________________________________________________________________
Writer::Writer(std::ostream* out, size_t prec, bool pret, size_t indent)
    : _out(out), _pretty(pret), _indent(indent), _floatPrec(prec) {}

// _____________________________________________________________________________
void Writer::obj() {
  if (!_stack.empty() && _stack.top().type == OBJ)
    throw WriterException("Object not allowed as key");
  if (!_stack.empty() && _stack.top().type == KEY) _stack.pop();
  if (!_stack.empty() && _stack.top().type == ARR) valCheck();
  if (_stack.size() && _stack.top().type == ARR) prettor();
  *_out << "{";
  _stack.push({OBJ, 1});
}

// _____________________________________________________________________________
void Writer::key(const std::string& k) {
  if (_stack.empty() || _stack.top().type != OBJ)
    throw WriterException("Keys only allowed in objects.");
  if (!_stack.top().empty) (*_out) << "," << (_pretty ? " " : "");
  _stack.top().empty = 0;
  prettor();
  *_out << "\"" << k << "\""
        << ":" << (_pretty ? " " : "");
  _stack.push({KEY, 1});
}

// _____________________________________________________________________________
void Writer::valCheck() {
  if (_stack.empty() || (_stack.top().type != KEY && _stack.top().type != ARR))
    throw WriterException("Value not allowed here.");
  if (!_stack.empty() && _stack.top().type == KEY) _stack.pop();
  if (!_stack.empty() && _stack.top().type == ARR) {
    if (!_stack.top().empty) (*_out) << "," << (_pretty ? " " : "");
    _stack.top().empty = 0;
  }
}

// _____________________________________________________________________________
void Writer::val(const std::string& v) {
  valCheck();
  *_out << "\"" << util::jsonStringEscape(v) << "\"";
}

// _____________________________________________________________________________
void Writer::val(const char* v) {
  valCheck();
  *_out << "\"" << util::jsonStringEscape(v) << "\"";
}

// _____________________________________________________________________________
void Writer::val(bool v) {
  valCheck();
  *_out << (v ? "true" : "false");
}

// _____________________________________________________________________________
void Writer::val(int v) {
  valCheck();
  *_out << v;
}

// _____________________________________________________________________________
void Writer::val(double v) {
  valCheck();
  *_out << std::fixed << std::setprecision(_floatPrec) << v;
}

// _____________________________________________________________________________
void Writer::val(Null) {
  valCheck();
  *_out << "null";
}

// _____________________________________________________________________________
void Writer::val(const Val& v) {
  switch (v.type) {
    case Val::JSNULL:
      val(Null());
      return;
    case Val::INT:
      val(v.i);
      return;
    case Val::FLOAT:
      val(v.f);
      return;
    case Val::BOOL:
      val((bool)v.i);
      return;
    case Val::STRING:
      val(v.str);
      return;
    case Val::ARRAY:
      arr();
      for (const Val& varr : v.arr) val(varr);
      close();
      return;
    case Val::DICT:
      obj();
      for (const auto& vdic : v.dict) {
        keyVal(vdic.first, vdic.second);
      };
      close();
      return;
  }
}

// _____________________________________________________________________________
void Writer::arr() {
  if (!_stack.empty() && _stack.top().type == OBJ)
    throw WriterException("Array not allowed as key");
  if (!_stack.empty() && _stack.top().type == KEY) _stack.pop();
  if (!_stack.empty() && _stack.top().type == ARR) valCheck();
  *_out << "[";
  _stack.push({ARR, 1});
}

// _____________________________________________________________________________
void Writer::prettor() {
  if (_pretty) {
    *_out << "\n";
    for (size_t i = 0; i < _indent * _stack.size(); i++) (*_out) << " ";
  }
}

// _____________________________________________________________________________
void Writer::closeAll() {
  while (!_stack.empty()) close();
}

// _____________________________________________________________________________
void Writer::close() {
  if (_stack.empty()) return;
  switch (_stack.top().type) {
    case OBJ:
      _stack.pop();
      prettor();
      (*_out) << "}";
      break;
    case ARR:
      _stack.pop();
      (*_out) << "]";
      break;
    case KEY:
      throw WriterException("Missing value.");
  }
}