/* (c) https://github.com/MontiCore/monticore */
package de.monticore.literals;

/* This is a MontiCore stable grammar.
 * Adaptations -- if any -- are conservative. */

import de.monticore.literals.*;

/**
 *
 * This grammar defines Java compliant literals. The scope of this grammar
 * is to ease the reuse of literals structures in Java-like sublanguages,
 * e.g., by grammar inheritance or grammar embedment.
 * The grammar contains literals from Java, e.g., Boolean, Char, String, ....
 * Please note that Java has an extended syntax e.g. for integers
 * using underscores or other kinds of encodings.
 * They parse e.g. 999_999 or 0x3F2A
 *
*/

component grammar MCJavaLiterals extends MCCommonLiterals {



  /*========================================================================*/
  /*======================= INTERFACE DEFINITIONS ==========================*/
  /*========================================================================*/

  /*========================================================================*/
  /*============================ PARSER RULES ==============================*/
  /*========================================================================*/


  /** ASTIntLiteral represents a positive Integer number.
        @attribute source String-representation (including '"').
    */
  IntLiteral implements NumericLiteral <100> =
    source:Num_Int ;


  /** ASTLongLiteral represents a positive Long number.
        @attribute source String-representation (including '"').
    */
  LongLiteral implements NumericLiteral <99> =
    source:Num_Long ;


  /** ASTFloatLiteral represents a positive Float number.
        @attribute source String-representation (including '"').
    */
  FloatLiteral implements NumericLiteral <100> =
     source:Num_Float ;



  /** ASTDoubleLiteral represents a positive Double number.
        @attribute source String-representation (including '"').
    */
  DoubleLiteral implements NumericLiteral <100> =
    source:Num_Double ;


  /*========================================================================*/
  /*============================ LEXER RULES ===============================*/
  /*========================================================================*/


   /*========================================================================*/
   /* The following section is adapted from                                  */
   /* https://github.com/antlr/grammars-v4/blob/master/java/Java.g4          */
   /*========================================================================*/

   // §3.10.1 Integer Literals

   token Num_Int
     = DecimalIntegerLiteral | HexIntegerLiteral
       | OctalIntegerLiteral | BinaryIntegerLiteral;

   token Num_Long
     = DecimalIntegerLiteral IntegerTypeSuffix
       | HexIntegerLiteral IntegerTypeSuffix
       | OctalIntegerLiteral IntegerTypeSuffix
       | BinaryIntegerLiteral IntegerTypeSuffix;

   fragment token DecimalIntegerLiteral
     = DecimalNumeral;

   fragment token HexIntegerLiteral
     = HexNumeral;

   fragment token OctalIntegerLiteral
     = OctalNumeral;

   fragment token BinaryIntegerLiteral
     = BinaryNumeral;

   fragment token IntegerTypeSuffix
     = 'l' | 'L';

   fragment token DecimalNumeral
     = '0' | NonZeroDigit (Digits? | Underscores Digits);

   @Override
   fragment token Digits
     = Digit (DigitOrUnderscore* Digit)?;

   @Override
   fragment token Digit
     = '0' | NonZeroDigit;

   fragment token NonZeroDigit
     = '1'..'9' ;

   fragment token DigitOrUnderscore
     = Digit | '_';

   fragment token Underscores
     = '_'+;

   fragment token HexNumeral
     = '0' ('x' | 'X') HexDigits;

   fragment token HexDigits
     = HexDigit (HexDigitOrUnderscore* HexDigit)?;

   @Override
   fragment token HexDigit
     = '0'..'9'  | 'a'..'f'  | 'A'..'F' ;

   fragment token HexDigitOrUnderscore
     = HexDigit | '_';

   fragment token OctalNumeral
     = '0' Underscores? OctalDigits;

   fragment token OctalDigits
     = OctalDigit (OctalDigitOrUnderscore* OctalDigit)?;

   @Override
   fragment token OctalDigit
     = '0'..'7' ;

   fragment token OctalDigitOrUnderscore
     = OctalDigit | '_';

   fragment token BinaryNumeral
     = '0' ('b' | 'B') BinaryDigits;

   fragment token BinaryDigits
     = BinaryDigit (BinaryDigitOrUnderscore* BinaryDigit)?;

   fragment token BinaryDigit
     = '0' | '1';

   fragment token BinaryDigitOrUnderscore
     = BinaryDigit | '_';


   // §3.10.2 Floating-Point Literals

   token Num_Float
     = DecimalFloatingPointLiteral | HexadecimalFloatingPointLiteral;

   token Num_Double
     = DecimalDoublePointLiteral | HexadecimalDoublePointLiteral;

   fragment token DecimalDoublePointLiteral
     =   Digits '.' Digits? ExponentPart? DoubleTypeSuffix?
       |        '.' Digits  ExponentPart? DoubleTypeSuffix?
       | Digits             ExponentPart  DoubleTypeSuffix?
       | Digits                           DoubleTypeSuffix;

   fragment token DecimalFloatingPointLiteral
     =   Digits '.' Digits? ExponentPart? FloatTypeSuffix
       |        '.' Digits  ExponentPart? FloatTypeSuffix
       | Digits             ExponentPart  FloatTypeSuffix
       | Digits                           FloatTypeSuffix;

   fragment token ExponentPart
     = ExponentIndicator SignedInteger;

   fragment token ExponentIndicator
     = 'e' | 'E';

   fragment token SignedInteger
     = Sign? Digits;

   fragment token Sign
     = '+' | '-';

   fragment token FloatTypeSuffix
     = 'f' | 'F';

   fragment token DoubleTypeSuffix
     = 'd' | 'D';

   fragment token HexadecimalDoublePointLiteral
     = HexSignificand BinaryExponent DoubleTypeSuffix?;

   fragment token HexadecimalFloatingPointLiteral
     = HexSignificand BinaryExponent FloatTypeSuffix;

   fragment token HexSignificand
     = HexNumeral '.'? | '0' ('x' | 'X') HexDigits? '.' HexDigits;

   fragment token BinaryExponent
     = BinaryExponentIndicator SignedInteger;

   fragment token BinaryExponentIndicator
     = 'p' | 'P';

  /*========================================================================*/
  /*======================= AST DEFINITIONS ================================*/
  /*========================================================================*/


  astrule IntLiteral =
    method public int getValue() {
      return de.monticore.literals.MCLiteralsDecoder.decodeInt(getSource());
    }
  ;

  astrule LongLiteral =
    method public long getValue() {
      return de.monticore.literals.MCLiteralsDecoder.decodeLong(getSource());
    }
  ;


  astrule FloatLiteral =
    method public float getValue() {
      return de.monticore.literals.MCLiteralsDecoder.decodeFloat(getSource());
    }
  ;


  astrule DoubleLiteral =
    method public double getValue() {
      return de.monticore.literals.MCLiteralsDecoder.decodeDouble(getSource());
    }
  ;

 }