-- Copyright 2006-2010 Mitchell Foral mitchell<att>caladbolg.net. See LICENSE.
-- Makefile LPeg Lexer

module(..., package.seeall)
local P, R, S = lpeg.P, lpeg.R, lpeg.S
local nonnewline = nonnewline_esc
-- local ws = token('whitespace', S('\r\n\f\t ')^1)
local nl = P('\r')^-1*P('\n')
local ws = token('whitespace', (S('\f\t ')+P'\\'*nl)^1)
local nl = token('whitespace', S('\r\n')^1)
-- nl = nil

local assign = token('operator', P(':')^-1 * '=')
local colon = token('operator', ':') * -P('=')

-- comments
local comment = token('comment', '#' * nonnewline^0)

-- preprocessor
local preproc = token('preprocessor', '!' * nonnewline^0)

-- targets
local target = token('target', (nonnewline - ':')^1) * colon

-- commands
-- local command = #P('\t') * token('command', nonnewline^1)

-- keywords
local keyword = token('keyword', word_match(word_list{
  'ifdef', 'ifndef', 'ifeq', 'ifneq', 'else', 'endif',
  'include', 'vpath',
}))

-- lines
local var_char = any - space - S(':#=')
local nonws = (nonnewline - space)^1
local identifier = token('identifier', var_char^1) * ws^0 * assign * ws^0
local macro = token('macro', '$' * (delimited_range('()', nil, nil, true) + S('<@^')))
local in_line = ws + identifier + keyword + macro

local regular_line = (in_line + token('line', nonws))^1
local command = #P('\t') * (in_line + token('command', nonws))^1
      target = target * in_line^0

function LoadTokens()
 local makefile = makefile
 add_token(makefile, 'comment', comment)
 add_token(makefile, 'preprocessor', preproc)
 add_token(makefile, 'target', target)
 add_token(makefile, 'command', command)
 add_token(makefile, 'regular_line', regular_line)
 add_token(makefile, 'whitespace', nl)
end

function LoadStyles()
  add_style('line', style_nothing)
  add_style('target', style_definition)
  add_style('command', style_string)
  add_style('identifier', style_nothing..{ bold = true })
  add_style('macro', style_keyword..{ bold = false })
end