import regex
from mode import Fundamental
from tab import StackTabber
from lex import Grammar, PatternRule, RegionRule
from mode.python import StringGrammar2

class LispGrammar(Grammar):
    rules = [
        PatternRule(r'comment', r';.*$'),
        PatternRule(r'delimiter', r'[()]'),
        PatternRule(r'keyword', r'(?:or|not|list|let\*|let|lambda|if|cons|c[ad]+r|apply|and)(?![^\"\' \t()])'),
        PatternRule(r'lisp_word', r"[^\"' \t()]+"),
        RegionRule(r'string', r'"', StringGrammar2, r'"'),
        PatternRule(r'spaces', r' +'),
        PatternRule(r'eol', r'\n'),
    ]

class LispTabber(StackTabber):
    wsre = regex.whitespace
    wst  = ('spaces', 'null', 'eol',)
    sre  = regex.space
    st   = ('spaces', 'null',)
    def _handle_open_token(self, currlvl, y, i):
        token  = self.get_token(y, i)
        rtoken = self.get_next_right_token(y, i)
        if rtoken is None:
            level = self.get_curr_level() + self.mode.tabwidth
        elif rtoken.string not in ('(', 'define', 'lambda'):
            rtoken = self.get_next_right_token(y, i + 1)
            if rtoken is None or rtoken.string != '(':
                level = self.get_curr_level() + self.mode.tabwidth
            else:
                level = rtoken.x
        else:
            level = self.get_curr_level() + self.mode.tabwidth
        self._append(token.string, level)
        return currlvl

class Lisp(Fundamental):
    name        = 'Lisp'
    tabwidth    = 2
    tabbercls   = LispTabber
    grammar     = LispGrammar
    commentc    = ';'
    opentokens  = ('delimiter',)
    opentags    = {'(': ')'}
    closetokens = ('delimiter',)
    closetags   = {')': '('}
    _bindings   = {
        'close-paren':   (')',),
        'close-brace':   ('}',),
        'close-bracket': (']',),
    }
    commentc = ';'

install = Lisp.install