" vim: ts=8
" Vim syntax file
" Language:     ANTLRv3
" Maintainer:   Jörn Horstmann (updated by Davyd Madeley)
" Last Change:  2008-11-21

" For version 5.x: Clear all syntax items
" For version 6.x: Quit when a syntax file was already loaded
if version < 600
  syntax clear
elseif exists("b:current_syntax")
  finish
endif

syn keyword antlrKeyword grammar lexer parser tree header members options fragment returns throws scope init

syn match  antlrCharacter '\\\(r\|n\|t\|f\|b\|"\|\'\|\\\|u\x\{4}\)' contained display

syn match antlrToken "\<[A-Z_][a-zA-Z_0-9]\+\>"
syn match antlrRule "[a-z][a-zA-Z_0-9]\+"
syn match antlrScopeVariable '$\k\+::\k\+'

syn match antlrOperator "[:;@.]"
syn match antlrOperator "[()]"
syn match antlrOperator "[?+*~|!]"
syn match antlrOperator "[->=^]"

syn match antlrBrace "[{}]"
syn match antlrBrace "[\[\]]"
syn region antlrAction matchgroup=antlrBrace start="[{\[]" end="[}\]]" contains=antlrVariable,antlrLiteral,antlrComment
syn match antlrVariable contained "$[a-zA-Z][a-zA-Z_0-9]*"

syn region antlrLiteral start=+'+ end=+'+ contains=antlrCharacter
syn region antlrLiteral start=+"+ end=+"+ contains=antlrCharacter

syn region antlrComment start="/\*" end="\*/"
syn match  antlrComment "//.*$"

" Define the default highlighting.
" For version 5.7 and earlier: only when not done already
" For version 5.8 and later: only when an item doesn't have highlighting yet
if version >= 508
  if version < 508
    let did_antlr_syntax_inits = 1
    command -nargs=+ HiLink hi link <args>
  else
    command -nargs=+ HiLink hi def link <args>
  endif

  HiLink antlrLiteral           String
  hi def antlrVariable		term=bold cterm=bold gui=bold
  HiLink antlrBrace		Operator
  HiLink antlrCharacter         Special
  HiLink antlrComment           Comment
  HiLink antlrOperator          Operator
  HiLink antlrKeyword           Keyword
  HiLink antlrToken             PreProc
  HiLink antlrScopeVariable     Identifier
  HiLink antlrRule		Type

  delcommand HiLink
endif

" try to figure out the target language
let target_languages = []
" can we figure out from the file name
let extensions = split(expand('%:t'), '\.')
if len(extensions) >= 3
  " great.. the target language was provided via file name
  call add(target_languages, tolower(extensions[-2]))
else
  " no multiple extensions... have to figure out from the content
  let buffer = join(getline(1, line('$')), "\n")
  let antlr_options = matchstr(buffer, '\m\(\_s\|;\)options\_s\+{\_.\{-\}}')
  call substitute(antlr_options, '\mlanguage\_s*=\_s*''\?\(.\{-\}\)''\?\_s*;', '\=add(target_languages, tolower(submatch(1)))', 'g')
endif
if exists('target_languages[-1]')
  " the last defined target language takes precendece
  let lang=target_languages[-1]
  let syntax_file = findfile('syntax/' . lang . '.vim', &rtp, 1)
  if syntax_file != ''
    " if a valid syntax file was found only
    let b:current_syntax = ''
    unlet b:current_syntax
    let region_name = '@' . lang . 'Language'
    exe 'syntax include ' . region_name . ' ' . syntax_file
    exe 'syntax region ' . lang . ' start="{" end="}" keepend contains=' . region_name
  endif
endif

let b:current_syntax = "antlr3"