-- Copyright 2006-2023 Mitchell. See LICENSE.
-- Django LPeg lexer.
local lexer = lexer
local P, S = lpeg.P, lpeg.S

local lex = lexer.new(...)

-- Keywords.
lex:add_rule('keyword', lex:tag(lexer.KEYWORD, lex:word_match(lexer.KEYWORD)))

-- Functions.
lex:add_rule('function', lpeg.B('|') *
                 lex:tag(lexer.FUNCTION_BUILTIN,
                         lex:word_match(lexer.FUNCTION_BUILTIN)))

-- Identifiers.
lex:add_rule('identifier', lex:tag(lexer.IDENTIFIER, lexer.word))

-- Strings.
lex:add_rule('string', lex:tag(lexer.STRING, lexer.range('"', false, false)))

-- Operators.
lex:add_rule('operator', lex:tag(lexer.OPERATOR, S(':,.|')))

-- Embed Django in HTML.
local html = lexer.load('html')
html:add_rule('django_comment',
              lex:tag(lexer.COMMENT, lexer.range('{#', '#}', true)))
local django_start_rule = lex:tag(lexer.PREPROCESSOR, '{' * S('{%'))
local django_end_rule = lex:tag(lexer.PREPROCESSOR, S('%}') * '}')
html:embed(lex, django_start_rule, django_end_rule)

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

-- Word lists.
lex:set_word_list(lexer.KEYWORD, {
    'autoescape', 'endautoescape', 'block', 'endblock', 'comment', 'endcomment',
    'csrf_token', 'cycle', 'as', 'debug', 'extends', 'filter', 'endfilter',
    'firstof', 'for', 'in', 'endfor', 'empty', 'if', 'elif', 'else', 'endif',
    'and', 'or', 'not', 'is', 'ifchanged', 'endifchanged', 'include', 'load',
    'lorem', 'now', 'regroup', 'resetcycle', 'spaceless', 'endspaceless',
    'templatetag', 'url', 'verbatim', 'endverbatim', 'widthratio', 'with',
    'endwith', --
    'blocktranslate', 'endblocktranslate', 'translate', 'language',
    'get_available_languages', 'get_current_language',
    'get_current_language_bidi', 'get_language_info', 'get_language_info_list', --
    'get_static_prefix', 'get_media_prefix'
})

lex:set_word_list(lexer.FUNCTION_BUILTIN, {
    'add', 'addslashes', 'capfirst', 'center', 'cut', 'date', 'default',
    'default_if_none', 'dictsort', 'dictsortreversed', 'divisibleby', 'escape',
    'escapejs', 'filesizeformat', 'first', 'floatformat', 'force_escape',
    'get_digit', 'iriencode', 'join', 'json_script', 'last', 'length',
    'length_is', 'linebreaks', 'linebreaksbr', 'linenumbers', 'ljust', 'lower',
    'make_list', 'phone2numeric', 'pluralize', 'pprint', 'random', 'rjust',
    'safe', 'safeseq', 'slice', 'slugify', 'stringformat', 'striptags', 'time',
    'timesince', 'timeuntil', 'title', 'truncatechars_html', 'truncatewords',
    'truncatewords_html', 'unordered_list', 'upper', 'urlencode', 'urlize',
    'urlizetrunc', 'wordcount', 'wordwrap', 'yesno', --
    'language_name', 'language_name_local', 'language_bidi',
    'language_name_translated'
})

lexer.property['scintillua.comment'] = '{#|#}'

return lex
