-- Copyright 2015-2020 Mitchell. See LICENSE.
-- PowerShell LPeg lexer.
-- Contributed by Jeff Stone.

local lexer = require('lexer')
local token, word_match = lexer.token, lexer.word_match
local P, S = lpeg.P, lpeg.S

local lex = lexer.new('powershell')

-- Whitespace.
lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))

-- Comments.
lex:add_rule('comment', token(lexer.COMMENT, lexer.to_eol('#')))

-- Keywords.
lex:add_rule('keyword', token(lexer.KEYWORD, word_match([[
  Begin Break Continue Do Else End Exit For ForEach ForEach-Object Get-Date
  Get-Random If Param Pause Powershell Process Read-Host Return Switch While
  Write-Host
]], true)))

-- Comparison Operators.
lex:add_rule('comparison', token(lexer.KEYWORD, '-' * word_match([[
  and as band bor contains eq ge gt is isnot le like lt match ne nomatch not
  notcontains notlike or replace
]], true)))

-- Parameters.
lex:add_rule('parameter', token(lexer.KEYWORD, '-' * word_match([[
  Confirm Debug ErrorAction ErrorVariable OutBuffer OutVariable Verbose WhatIf
]], true)))

-- Properties.
lex:add_rule('property', token(lexer.KEYWORD, '.' * word_match([[
  day dayofweek dayofyear hour millisecond minute month second timeofday year
]], true)))

-- Types.
lex:add_rule('type', token(lexer.KEYWORD, '[' * word_match([[
  array boolean byte char datetime decimal double hashtable int long single
  string xml
]], true) * ']'))

-- Variables.
lex:add_rule('variable', token(lexer.VARIABLE, '$' *
  (lexer.digit^1 + lexer.word + lexer.range('{', '}', true))))

-- Strings.
lex:add_rule('string', token(lexer.STRING, lexer.range('"', true)))

-- Numbers.
lex:add_rule('number', token(lexer.NUMBER, lexer.number))

-- Operators.
lex:add_rule('operator', token(lexer.OPERATOR, S('=!<>+-/*^&|~.,:;?()[]{}%`')))

-- Fold points.
lex:add_fold_point(lexer.OPERATOR, '{', '}')

return lex
