%YAML 1.2
---
name: Merlin Assembler
file_extensions: [S]
scope: source.asm.65816.merlin

variables:
  ws: '[ \t]+'
  ident: '[:-~][0-~]*'

contexts:
  prototype:
    - include: comment
    - include: eol
  main:

    - meta_include_prototype: false

    - match: ^[;*]
      push:
        - meta_scope: comment.line
        - match: \n
          pop: true

    - match: '{{ws}}'
      push: opcode

    - match: '^({{ident}}){{ws}}((?i)MAC)\b'
      captures:
        1: entity.name.macro
        2: keyword.directive
      push: operand


    - match: '^({{ident}}){{ws}}((?i)ENT)\b'
      captures:
        1: entity.name.function
        2: keyword.directive
      push: operand

    - match: '^({{ident}}){{ws}}((?i)EQU)\b'
      captures:
        1: entity.name.constant
        2: keyword.directive
      push: operand

    - match: '^({{ident}}){{ws}}(=)'
      captures:
        1: entity.name.constant
        2: keyword.directive
      push: operand



    - match: '^{{ident}}'
      scope: entity.name.label


  opcode:
    - match: '{{ws}}'
      set: operand
    - include: comment
    - include: scope:source.asm.65816#mnemonics-6502
    - include: scope:source.asm.65816#mnemonics-65c02
    - include: scope:source.asm.65816#mnemonics-65816
    - include: scope:source.asm.65816#mnemonics-65816-long
    - include: mnemonics-65816-alt

    # toolbox macros
    - match: \b_[A-Za-z0-9]+\b
      scope: support.function.macro.toolbox
    - match: ~[A-Za-z0-9]+\b
      scope: support.function.macro.toolbox


    - match: \b(?i:DFB|DB|DDB|DA|DW|ADR|ADRL|DS)\b
      scope: keyword.directive.data

    - match: \b(?i:HEX)\b
      scope: keyword.directive.data
      set: operand-hex

    - match: \b(?i:ASC|DCI|INV|FLS|REV|STR|STRL|FLO)\b
      scope: keyword.directive.data
      set: operand-string

    - match: \b(?i:LUP)\b
      scope: keyword.control.conditional
    - match: =|<<<|--\^|>>>
      scope: keyword.directive

    - match: \b(?i:PMC|ORG|REL|TYP|DUM|DEND|END|CHK|DAT|ERR|EXT|EXD|OBJ|VAR|AST|DAT|PAG|SKP|CHK|ERR|KBD|PAU|SW|USR)\b
      scope: keyword.directive


    - match: \b(?i:DO|ELSE|IF|FIN)\b
      scope: keyword.control.conditional

    - match: \b(?i:USE|PUT|PUTBIN)\b
      scope: keyword.control.import
      set: operand-path

    - match: \b(?i:DSK|SAV|LNK)\b
      scope: keyword.control.export
      set: operand-path

    - match: \b(?i:XC)\b
      scope: keyword.directive
      set: operand-off

    - match: \b(?i:CAS)\b
      scope: keyword.directive
      set: operand-cas

    - match: \b(?i:CYC)\b
      scope: keyword.directive
      set: operand-cyc

    - match: \b(?i:EXP)\b
      scope: keyword.directive
      set: operand-exp


    - match: \b(?i:LST)\b
      scope: keyword.directive
      set: operand-lst

    - match: \b(?i:LSTDO)\b
      scope: keyword.directive
      set: operand-off

    - match: \b(?i:TTL)\b
      scope: keyword.directive
      set: operand-string

    - match: \b(?i:TR)\b
      scope: keyword.directive
      set: operand-tr



  operand:
    - include: numbers
    - include: strings
    #- include: macro-parm 

  operand-hex:
    - match: '[0-9A-Fa-f]{2}'
      scope: constant.numeric.hex
    - match: '[^ \t,]'
      scope: invalid.illegal.operand


  operand-path:
    - match: \S+
      scope: string.unquoted
      set: expect-comment
    - include: expect-comment

  operand-string:
    - include: strings
    - match: '[0-9A-Fa-f]{2}'
      scope: constant.numeric.hex
    - match: '[^ \t,]'
      scope: invalid.illegal.operand
    


  operand-off:
    - match: \b(?i:OFF)\b
      scope: constant.language
      set: expect-comment
    - include: expect-comment

  operand-cas:
      # cas se / cas in
    - match: \b(?i:SE|IN)\b
      scope: constant.language
      set: expect-comment
    - include: expect-comment

  operand-cyc:
      # cyc off | ave | flags
    - match: \b(?i:OFF|AVE|FLAGS)\b
      scope: constant.language
      set: expect-comment
    - include: expect-comment


  operand-exp:
      # exp on | off | only
    - match: \b(?i:ON|OFF|ONLY)\b
      scope: constant.language
      set: expect-comment
    - include: expect-comment

  operand-lst:
      # lst | lst ON | OFF | RTN | FILE,path...
    - match: \b(?i:ON|OFF|RTN)\b
      scope: constant.language
      set: expect-comment

    - match: \b(?i:FILE){{ws}}*,
      scope: constant.language
      set: operand-path

    - include: expect-comment


  operand-tr:
      # tr on | off | adr
    - match: \b(?i:ON|OFF|ADR)\b
      scope: constant.language
      set: expect-comment
    - include: expect-comment

  expect-comment:
    - include: comment
    - match: \S
      scope: invalid.illegal.expect.comment

  comment:
    - match: ;
      push:
        - meta_scope: comment.line
        - match: \n
          pop: true
    - include: eol


  mnemonics-65816-alt:
    - match: \b(?i:TAS|TSA|SWA|TAD|TDA|BLT|BGE)\b
      scope: keyword.mnemonic.65816.alt

  numbers:
    - match: \d+
      scope: constant.numeric
    - match: \$[0-9a-fA-F]+
      scope: constant.numeric.hex
    - match: \%[01_]+
      scope: constant.numeric.binary

  strings:
    - match: "'"
      scope: punctuation.definition.string.begin
      push:
        - meta_include_prototype: false
        - meta_scope: string.quoted.single
        - match: "'"
          scope: punctuation.definition.string.end
          pop: true
        - match: \n
          scope: invalid.illegal.newline.asm
          pop: true
    - match: '"'
      scope: punctuation.definition.string.begin
      push:
        - meta_include_prototype: false
        - meta_scope: string.quoted.double
        - match: '"'
          scope: punctuation.definition.string.end
          pop: true
        - match: \n
          scope: invalid.illegal.newline.asm
          pop: true

  eol:
    - match: '$'
      pop: true