prettywriter.h

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// Tencent is pleased to support the open source community by making RapidJSON available.
//
// Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved.
//
// Licensed under the MIT License (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
// http://opensource.org/licenses/MIT
//
// Unless required by applicable law or agreed to in writing, software distributed
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, either express or implied. See the License for the
// specific language governing permissions and limitations under the License.

#ifndef RAPIDJSON_PRETTYWRITER_H_
#define RAPIDJSON_PRETTYWRITER_H_

#include "writer.h"

#if __GNUC__
RAPIDJSON_DIAG_PUSH
RAPIDJSON_DIAG_OFF(effc++)
#endif

#if defined(__clang__)
RAPIDJSON_DIAG_PUSH
RAPIDJSON_DIAG_OFF(c++ 98 - compat)
#endif

RAPIDJSON_NAMESPACE_BEGIN


enum PrettyFormatOptions
{
  kFormatDefault = 0,         
  kFormatSingleLineArray = 1  
};


template <typename OutputStream, typename SourceEncoding = UTF8<>, typename TargetEncoding = UTF8<>,
          typename StackAllocator = CrtAllocator, unsigned writeFlags = kWriteDefaultFlags>
class PrettyWriter : public Writer<OutputStream, SourceEncoding, TargetEncoding, StackAllocator, writeFlags>
{
public:
  typedef Writer<OutputStream, SourceEncoding, TargetEncoding, StackAllocator, writeFlags> Base;
  typedef typename Base::Ch Ch;


  explicit PrettyWriter(OutputStream& os, StackAllocator* allocator = 0, size_t levelDepth = Base::kDefaultLevelDepth)
    : Base(os, allocator, levelDepth), indentChar_(' '), indentCharCount_(4), formatOptions_(kFormatDefault)
  {
  }

  explicit PrettyWriter(StackAllocator* allocator = 0, size_t levelDepth = Base::kDefaultLevelDepth)
    : Base(allocator, levelDepth), indentChar_(' '), indentCharCount_(4)
  {
  }

#if RAPIDJSON_HAS_CXX11_RVALUE_REFS
  PrettyWriter(PrettyWriter&& rhs)
    : Base(std::forward<PrettyWriter>(rhs))
    , indentChar_(rhs.indentChar_)
    , indentCharCount_(rhs.indentCharCount_)
    , formatOptions_(rhs.formatOptions_)
  {
  }
#endif


  PrettyWriter& SetIndent(Ch indentChar, unsigned indentCharCount)
  {
    RAPIDJSON_ASSERT(indentChar == ' ' || indentChar == '\t' || indentChar == '\n' || indentChar == '\r');
    indentChar_ = indentChar;
    indentCharCount_ = indentCharCount;
    return *this;
  }


  PrettyWriter& SetFormatOptions(PrettyFormatOptions options)
  {
    formatOptions_ = options;
    return *this;
  }


  bool Null()
  {
    PrettyPrefix(kNullType);
    return Base::EndValue(Base::WriteNull());
  }
  bool Bool(bool b)
  {
    PrettyPrefix(b ? kTrueType : kFalseType);
    return Base::EndValue(Base::WriteBool(b));
  }
  bool Int(int i)
  {
    PrettyPrefix(kNumberType);
    return Base::EndValue(Base::WriteInt(i));
  }
  bool Uint(unsigned u)
  {
    PrettyPrefix(kNumberType);
    return Base::EndValue(Base::WriteUint(u));
  }
  bool Int64(int64_t i64)
  {
    PrettyPrefix(kNumberType);
    return Base::EndValue(Base::WriteInt64(i64));
  }
  bool Uint64(uint64_t u64)
  {
    PrettyPrefix(kNumberType);
    return Base::EndValue(Base::WriteUint64(u64));
  }
  bool Double(double d)
  {
    PrettyPrefix(kNumberType);
    return Base::EndValue(Base::WriteDouble(d));
  }

  bool RawNumber(const Ch* str, SizeType length, bool copy = false)
  {
    RAPIDJSON_ASSERT(str != 0);
    (void)copy;
    PrettyPrefix(kNumberType);
    return Base::EndValue(Base::WriteString(str, length));
  }

  bool String(const Ch* str, SizeType length, bool copy = false)
  {
    RAPIDJSON_ASSERT(str != 0);
    (void)copy;
    PrettyPrefix(kStringType);
    return Base::EndValue(Base::WriteString(str, length));
  }

#if RAPIDJSON_HAS_STDSTRING
  bool String(const std::basic_string<Ch>& str)
  {
    return String(str.data(), SizeType(str.size()));
  }
#endif

  bool StartObject()
  {
    PrettyPrefix(kObjectType);
    new (Base::level_stack_.template Push<typename Base::Level>()) typename Base::Level(false);
    return Base::WriteStartObject();
  }

  bool Key(const Ch* str, SizeType length, bool copy = false)
  {
    return String(str, length, copy);
  }

#if RAPIDJSON_HAS_STDSTRING
  bool Key(const std::basic_string<Ch>& str)
  {
    return Key(str.data(), SizeType(str.size()));
  }
#endif

  bool EndObject(SizeType memberCount = 0)
  {
    (void)memberCount;
    RAPIDJSON_ASSERT(Base::level_stack_.GetSize() >= sizeof(typename Base::Level));  // not inside an Object
    RAPIDJSON_ASSERT(
        !Base::level_stack_.template Top<typename Base::Level>()->inArray);  // currently inside an Array, not Object
    RAPIDJSON_ASSERT(0 == Base::level_stack_.template Top<typename Base::Level>()->valueCount % 2);  // Object has a Key
                                                                                                     // without a Value

    bool empty = Base::level_stack_.template Pop<typename Base::Level>(1)->valueCount == 0;

    if (!empty)
    {
      Base::os_->Put('\n');
      WriteIndent();
    }
    bool ret = Base::EndValue(Base::WriteEndObject());
    (void)ret;
    RAPIDJSON_ASSERT(ret == true);
    if (Base::level_stack_.Empty())  // end of json text
      Base::Flush();
    return true;
  }

  bool StartArray()
  {
    PrettyPrefix(kArrayType);
    new (Base::level_stack_.template Push<typename Base::Level>()) typename Base::Level(true);
    return Base::WriteStartArray();
  }

  bool EndArray(SizeType memberCount = 0)
  {
    (void)memberCount;
    RAPIDJSON_ASSERT(Base::level_stack_.GetSize() >= sizeof(typename Base::Level));
    RAPIDJSON_ASSERT(Base::level_stack_.template Top<typename Base::Level>()->inArray);
    bool empty = Base::level_stack_.template Pop<typename Base::Level>(1)->valueCount == 0;

    if (!empty && !(formatOptions_ & kFormatSingleLineArray))
    {
      Base::os_->Put('\n');
      WriteIndent();
    }
    bool ret = Base::EndValue(Base::WriteEndArray());
    (void)ret;
    RAPIDJSON_ASSERT(ret == true);
    if (Base::level_stack_.Empty())  // end of json text
      Base::Flush();
    return true;
  }



  bool String(const Ch* str)
  {
    return String(str, internal::StrLen(str));
  }
  bool Key(const Ch* str)
  {
    return Key(str, internal::StrLen(str));
  }



  bool RawValue(const Ch* json, size_t length, Type type)
  {
    RAPIDJSON_ASSERT(json != 0);
    PrettyPrefix(type);
    return Base::EndValue(Base::WriteRawValue(json, length));
  }

protected:
  void PrettyPrefix(Type type)
  {
    (void)type;
    if (Base::level_stack_.GetSize() != 0)
    {  // this value is not at root
      typename Base::Level* level = Base::level_stack_.template Top<typename Base::Level>();

      if (level->inArray)
      {
        if (level->valueCount > 0)
        {
          Base::os_->Put(',');  // add comma if it is not the first element in array
          if (formatOptions_ & kFormatSingleLineArray)
            Base::os_->Put(' ');
        }

        if (!(formatOptions_ & kFormatSingleLineArray))
        {
          Base::os_->Put('\n');
          WriteIndent();
        }
      }
      else
      {  // in object
        if (level->valueCount > 0)
        {
          if (level->valueCount % 2 == 0)
          {
            Base::os_->Put(',');
            Base::os_->Put('\n');
          }
          else
          {
            Base::os_->Put(':');
            Base::os_->Put(' ');
          }
        }
        else
          Base::os_->Put('\n');

        if (level->valueCount % 2 == 0)
          WriteIndent();
      }
      if (!level->inArray && level->valueCount % 2 == 0)
        RAPIDJSON_ASSERT(type == kStringType);  // if it's in object, then even number should be a name
      level->valueCount++;
    }
    else
    {
      RAPIDJSON_ASSERT(!Base::hasRoot_);  // Should only has one and only one root.
      Base::hasRoot_ = true;
    }
  }

  void WriteIndent()
  {
    size_t count = (Base::level_stack_.GetSize() / sizeof(typename Base::Level)) * indentCharCount_;
    PutN(*Base::os_, static_cast<typename OutputStream::Ch>(indentChar_), count);
  }

  Ch indentChar_;
  unsigned indentCharCount_;
  PrettyFormatOptions formatOptions_;

private:
  // Prohibit copy constructor & assignment operator.
  PrettyWriter(const PrettyWriter&);
  PrettyWriter& operator=(const PrettyWriter&);
};

RAPIDJSON_NAMESPACE_END

#if defined(__clang__)
RAPIDJSON_DIAG_POP
#endif

#if __GNUC__
RAPIDJSON_DIAG_POP
#endif

#endif  // RAPIDJSON_RAPIDJSON_H_