JSONParser.h

#pragma once
 
#include <Foundation/Basics.h>
#include <Foundation/Containers/HybridArray.h>
#include <Foundation/IO/Stream.h>
 
class plLogInterface;
 
class PL_FOUNDATION_DLL plJSONParser
{
public:
  plJSONParser();
 
  virtual ~plJSONParser() = default;
 
  void SetLogInterface(plLogInterface* pLog) { m_pLogInterface = pLog; }
 
protected:
  void SetInputStream(plStreamReader& stream, plUInt32 uiFirstLineOffset = 0);
 
  bool ContinueParsing();
 
  void ParseAll();
 
  void SkipObject();
 
  void SkipArray();
 
  void ParsingError(plStringView sMessage, bool bFatal);
 
  plLogInterface* m_pLogInterface = nullptr;
 
private:
  virtual bool OnVariable(plStringView sVarName) = 0;
 
  virtual void OnReadValue(plStringView sValue) = 0;
 
  virtual void OnReadValue(double fValue) = 0;
 
  virtual void OnReadValue(bool bValue) = 0;
 
  virtual void OnReadValueNULL() = 0;
 
  virtual void OnBeginObject() = 0;
 
  virtual void OnEndObject() = 0;
 
  virtual void OnBeginArray() = 0;
 
  virtual void OnEndArray() = 0;
 
  virtual void OnParsingError(plStringView sMessage, bool bFatal, plUInt32 uiLine, plUInt32 uiColumn) {}
 
private:
  enum State
  {
    NotStarted,
    Finished,
    ReadingObject,
    ReadingArray,
    ReadingValue,
    ReadingVariable,
    ExpectSeparator
  };
 
  struct JSONState
  {
    JSONState() { m_State = NotStarted; }
 
    State m_State;
  };
 
  void StartParsing();
  void SkipWhitespace();
  void SkipString();
  void ReadString();
  double ReadNumber();
  void ReadWord();
 
  void ContinueObject();
  void ContinueArray();
  void ContinueVariable();
  void ContinueValue();
  void ContinueSeparator();
 
  bool ReadCharacter(bool bSkipComments);
  void ReadNextByte();
 
  void SkipStack(State s);
 
  plUInt8 m_uiCurByte;
  plUInt8 m_uiNextByte;
  plUInt32 m_uiCurLine;
  plUInt32 m_uiCurColumn;
 
  plStreamReader* m_pInput;
  plHybridArray<JSONState, 32> m_StateStack;
  plHybridArray<plUInt8, 4096> m_TempString;
 
  bool m_bSkippingMode;
};