////////////////////////////////////////////////////////////////////////////////
/*! @file CommandParser.c  MSDN command parser.
- Part of the MSDN firmware.
- Part of the Research Assistant project.
- Copyright(C) 2016, Viktor E. Bursian, St.Petersburg, Russia.
                     Viktor.Bursian@mail.ioffe.ru
*///////////////////////////////////////////////////////////////////////////////
#include "CommandParser.h"
#include "Microsin_USB_IO.h"
#include "zakavych.h"

const char * const  DeviceName = ZAKAVYCH(MSDN_SHORTNAME);

const char * const  BuildDate = __DATE__;


void  ProcessReceivedByte (const int16_t  received_byte)
{
  static uint8_t              ParserStage = 0;
                              //!< Parser stages:
                              //!< - 0 - command char expected;
                              //!< - 1 to 8 - argument digit or [CR]LF expected;
                              //!< - 9 -    got command and 8 digits,
                              //!<          [CR]LF expected;
                              //!< - 0xD0 - got command and CR, LF expected;
                              //!< - 0xDn - got command, n digits and CR,
                              //!<          LF expected;
                              //!< - 0xEn - got command, n digits and [CR]LF,
                              //!<          to be executed;
                              //!< - 0xF0 - sintax error encounted, LF expected.
                              //!< - 0xFF - sintax error encounted, got LF,
                              //!<          now, error to be reported.
  static char                 Command = ' ';
  static uint8_t              Argument8  = 0;
  static uint16_t             Argument16 = 0;
  static uint32_t             Argument32 = 0;
  int8_t                      ErrNo;

  switch( ParserStage ){
    case  0:
        if( (0x21 <= received_byte) && (received_byte <= 0x7F) ){
          Command = received_byte;
          Argument8 = 0;
          ParserStage = 1;
        }else if( received_byte == 0x0A ){
          ParserStage = 0xFF;
        }else{
          ParserStage = 0xF0;
        }
        break;
    case  1:
    case  2:
        if( received_byte == 0x0D ){
          ParserStage += 0xCF; // -1 + 0xD0
        }else if( received_byte == 0x0A ){
          ParserStage += 0xDF; // -1 + 0xE0
        }else{
          ParserStage++;
          if ((received_byte >= 0x41) && (received_byte <= 0x46) ){
            Argument8 = (Argument8 << 4) + (received_byte - 0x40 + 0x09);
          }else if( (received_byte >= 0x61) && (received_byte <= 0x66) ){
            Argument8 = (Argument8 << 4) + (received_byte - 0x60 + 0x09);
          }else if( (received_byte >= 0x30) && (received_byte <= 0x39) ){
            Argument8 = (Argument8 << 4) + (received_byte - 0x30);
          }else{
            ParserStage = 0xF0;
          }
        }
        break;
    case  3:
        Argument16 = Argument8;
    case  4:
        if( received_byte == 0x0D ){
          ParserStage += 0xCF; // -1 + 0xD0
        }else if( received_byte == 0x0A ){
          ParserStage += 0xDF; // -1 + 0xE0
        }else{
          ParserStage++;
          if ((received_byte >= 0x41) && (received_byte <= 0x46) ){
            Argument16 = (Argument16 << 4) + (received_byte - 0x40 + 0x09);
          }else if( (received_byte >= 0x61) && (received_byte <= 0x66) ){
            Argument16 = (Argument16 << 4) + (received_byte - 0x60 + 0x09);
          }else if( (received_byte >= 0x30) && (received_byte <= 0x39) ){
            Argument16 = (Argument16 << 4) + (received_byte - 0x30);
          }else{
            ParserStage = 0xF0;
          }
        }
        break;
    case  5:
        Argument32 = Argument16;
    case  6:
    case  7:
    case  8:
        if( received_byte == 0x0D ){
          ParserStage += 0xCF; // -1 + 0xD0
        }else if( received_byte == 0x0A ){
          ParserStage += 0xDF; // -1 + 0xE0
        }else{
          ParserStage++;
          if ((received_byte >= 0x41) && (received_byte <= 0x46) ){
            Argument32 = (Argument32 << 4) + (received_byte - 0x40 + 0x09);
          }else if( (received_byte >= 0x61) && (received_byte <= 0x66) ){
            Argument32 = (Argument32 << 4) + (received_byte - 0x60 + 0x09);
          }else if( (received_byte >= 0x30) && (received_byte <= 0x39) ){
            Argument32 = (Argument32 << 4) + (received_byte - 0x30);
          }else{
            ParserStage = 0xF0;
          }
        }
        break;
    case  9:
        if( received_byte == 0x0D ){
          ParserStage = 0xD8;
        }else if( received_byte == 0x0A ){
          ParserStage = 0xE8;
        }else{
          ParserStage = 0xF0;
        }
        break;
    case 0xD0:
    case 0xD1:
    case 0xD2:
    case 0xD3:
    case 0xD4:
    case 0xD5:
    case 0xD6:
    case 0xD7:
    case 0xD8:
        if( received_byte == 0x0A ){
          ParserStage += 0x10;
        }else{
          ParserStage = 0xF0;
        }
        break;
    case 0xF0:
        if( received_byte == 0x0A ){
          ParserStage = 0xFF;
        }
        break;
  }
  switch( ParserStage ){
    case  0xE0:
        if( Command == '?' ){
          SendCharToUSB('@');
          SendStringToUSB(DeviceName);
          Send_EOL_ToUSB();
        }else if( Command == ':' ){
          SendCharToUSB(':');
          SendStringToUSB(BuildDate);
          Send_EOL_ToUSB();
        }else if( (ErrNo = ExecuteCommand0(Command)) ){
          SendCharToUSB('#');
          SendCharToUSB(0x30+ErrNo);
          Send_EOL_ToUSB();
        }
        ParserStage = 0;
        break;
    case  0xE1:
    case  0xE2:
        if( (ErrNo = ExecuteCommand2(Command,Argument8)) ){
          SendCharToUSB('#');
          SendCharToUSB(0x30+ErrNo);
          Send_EOL_ToUSB();
        }
        ParserStage = 0;
        break;
    case  0xE3:
    case  0xE4:
        if( (ErrNo = ExecuteCommand4(Command,Argument16)) ){
          SendCharToUSB('#');
          SendCharToUSB(0x30+ErrNo);
          Send_EOL_ToUSB();
        }
        ParserStage = 0;
        break;
    case  0xE5:
    case  0xE6:
    case  0xE7:
    case  0xE8:
        if( (ErrNo = ExecuteCommand8(Command,Argument32)) ){
          SendCharToUSB('#');
          SendCharToUSB(0x30+ErrNo);
          Send_EOL_ToUSB();
        }
        ParserStage = 0;
        break;
    case  0xFF:
        SendCharToUSB('#');
        Send_EOL_ToUSB();
        ParserStage = 0;
        break;
  }
}