import unittest

import pytest

from tatsu import tool
from tatsu.exceptions import FailedParse, FailedToken
from tatsu.ngcodegen import codegen
from tatsu.parser import EBNFBuffer
from tatsu.tool import compile
from tatsu.util import trim


class SyntaxTests(unittest.TestCase):
    def test_update_ast(self):
        grammar = """
            foo = name:"1" [ name: bar ] ;
            bar = { "2" } * ;
        """
        m = compile(grammar, 'Keywords')
        ast = m.parse('1 2')
        self.assertEqual(['1', ['2']], ast.name)

        grammar = """
            start = items: { item } * $ ;
            item = @:{ subitem } * "0" ;
            subitem = ?/1+/? ;
        """
        m = compile(grammar, 'Update')
        ast = m.parse('1101110100', nameguard=False)
        self.assertEqual([['11'], ['111'], ['1'], []], ast.items_)

    def test_include_and_override(self):
        gr = 'included_grammar'
        included_grammar = "plu = 'aaaa';"

        overridden = "%s@override\nplu = 'plu';"
        inclusion = f'#include :: {gr}.ebnf\n'

        including_grammar = overridden % (inclusion)
        whole_grammar = overridden % (included_grammar)

        class FakeIncludesBuffer(EBNFBuffer):
            def get_include(self, source, filename):
                return included_grammar, source + '/' + filename

        compile(FakeIncludesBuffer(whole_grammar), 'test')
        compile(FakeIncludesBuffer(including_grammar), 'test')

    def test_ast_assignment(self):
        grammar = """
            n  = @: {"a"}* $ ;
            f  = @+: {"a"}* $ ;
            nn = @: {"a"}*  @: {"b"}* $ ;
            nf = @: {"a"}*  @+: {"b"}* $ ;
            fn = @+: {"a"}* @: {"b"}* $ ;
            ff = @+: {"a"}* @+: {"b"}* $ ;
        """

        model = compile(grammar, 'test')

        def p(input, rule):
            return model.parse(input, start=rule, whitespace='')

        e = self.assertEqual

        e([], p('', 'n'))
        e(['a'], p('a', 'n'))
        e(['a', 'a'], p('aa', 'n'))

        e([[]], p('', 'f'))
        e([['a']], p('a', 'f'))
        e([['a', 'a']], p('aa', 'f'))

        for r in ('nn', 'nf', 'fn', 'ff'):
            e([[], []], p('', r))
            e([['a'], []], p('a', r))
            e([[], ['b']], p('b', r))
            e([['a', 'a'], []], p('aa', r))
            e([[], ['b', 'b']], p('bb', r))
            e([['a', 'a'], ['b']], p('aab', r))

    def test_optional_closure(self):
        grammar = 'start = foo+:"x" foo:{"y"}* {foo:"z"}* ;'
        model = compile(grammar, 'test')
        ast = model.parse('xyyzz', nameguard=False)
        self.assertEqual(['x', ['y', 'y'], 'z', 'z'], ast.foo)

        grammar = 'start = foo+:"x" [foo+:{"y"}*] {foo:"z"}* ;'
        model = compile(grammar, 'test')
        ast = model.parse('xyyzz', nameguard=False)
        self.assertEqual(['x', ['y', 'y'], 'z', 'z'], ast.foo)

        grammar = 'start = foo+:"x" foo:[{"y"}*] {foo:"z"}* ;'
        model = compile(grammar, 'test')
        ast = model.parse('xyyzz', nameguard=False)
        self.assertEqual(['x', ['y', 'y'], 'z', 'z'], ast.foo)

        grammar = 'start = foo+:"x" [foo:{"y"}*] {foo:"z"}* ;'
        model = compile(grammar, 'test')
        ast = model.parse('xyyzz', nameguard=False)
        self.assertEqual(['x', ['y', 'y'], 'z', 'z'], ast.foo)

    def test_optional_sequence(self):
        grammar = """
            start = '1' ['2' '3'] '4' $ ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('1234', nameguard=False)
        self.assertEqual(('1', '2', '3', '4'), ast)

        grammar = """
            start = '1' foo:['2' '3'] '4' $ ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('1234', nameguard=False)
        self.assertEqual(['2', '3'], ast.foo)

    def test_group_ast(self):
        grammar = """
            start = '1' ('2' '3') '4' $ ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('1234', nameguard=False)
        self.assertEqual(('1', '2', '3', '4'), ast)

    def test_partial_options(self):
        grammar = """
            start
                =
                [a]
                [
                    'A' 'A'
                |
                    'A' 'B'
                ]
                $
                ;
            a
                =
                'A' !('A'|'B')
                ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('AB', nameguard=False)
        self.assertEqual(('A', 'B'), ast)

    def test_partial_choice(self):
        grammar = """
            start
                =
                o:[o]
                x:'A'
                $
                ;
            o
                =
                'A' a:'A'
                |
                'A' b:'B'
                ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('A', nameguard=False)
        self.assertEqual({'x': 'A', 'o': None}, ast)

    def test_new_override(self):
        grammar = """
            start
                =
                @:'a' {@:'b'}
                $
                ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('abb', nameguard=False)
        self.assertEqual(['a', 'b', 'b'], ast)

    def test_list_override(self):
        grammar = """
            start
                =
                @+:'a' {@:'b'}
                $
                ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('a', nameguard=False)
        self.assertEqual(['a'], ast)

        grammar = """
            start
                =
                @:'a' {@:'b'}
                $
                ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('a', nameguard=False)
        self.assertEqual('a', ast)

    def test_based_rule(self):
        grammar = """\
            start
                =
                b $
                ;


            a
                =
                @:'a'
                ;


            b < a
                =
                {@:'b'}
                ;
            """
        model = compile(grammar, 'test')
        ast = model.parse('abb', nameguard=False)
        self.assertEqual(('a', 'b', 'b'), ast)
        self.assertEqual(trim(grammar), str(model))

    def test_rule_include(self):
        grammar = """
            start = b $;

            a = @:'a' ;
            b = >a {@:'b'} ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('abb', nameguard=False)
        self.assertEqual(('a', 'b', 'b'), ast)

    def test_48_rule_override(self):
        grammar = """
            start = ab $;

            ab = 'xyz' ;

            @override
            ab = @:'a' {@:'b'} ;
        """
        model = compile(grammar, 'test')
        ast = model.parse('abb', nameguard=False)
        self.assertEqual(('a', 'b', 'b'), ast)

    def test_failed_ref(self):
        grammar = r"""
            final = object;
            type = /[^\s=()]+/;
            object = '('type')' '{' @:{pair} {',' @:{pair}}* [','] '}';
            pair = key '=' value;
            list = '('type')' '[' @:{object} {',' @:{object}}* [','] ']';
            key = /[^\s=]+/;
            value = @:(string|list|object|unset|boolean|number|null) [','];
            null = '('type')' @:{ 'null' };
            boolean = /(true|false)/;
            unset = '<unset>';
            string = '"' @:/[^"]*/ '"';
            number = /-?[0-9]+/;
        """

        model = compile(grammar, 'final')
        codegen(model)
        model.parse('(sometype){boolean = true}')

    def test_empty_match_token(self):
        grammar = """
            table = { row }+ ;
            row = (cell1:cell "|" cell2:cell) "\n";
            cell = /[a-z]+/ ;
        """
        try:
            compile(grammar, 'model')
            self.fail('allowed empty token')
        except FailedParse:
            pass

    def test_empty_closure(self):
        grammar = """
            start = {'x'}+ {} 'y'$;
        """
        model = compile(grammar, 'test')
        codegen(model)
        ast = model.parse('xxxy', nameguard=False)
        self.assertEqual((['x', 'x', 'x'], [], 'y'), ast)

    def test_parseinfo(self):
        grammar = """
            start = head:{'x'}+ {} tail:'y'$;
        """
        model = compile(grammar, 'test')
        ast = model.parse('xxxy', nameguard=False, parseinfo=True)
        self.assertIsNotNone(ast)
        self.assertIsNotNone(ast.head)
        self.assertIsNotNone(ast.tail)
        self.assertIsNotNone(ast.parseinfo)

    def test_raw_string(self):
        grammar = r"""
            start = r'am\nraw' ;
        """
        pretty = r"""
            start
                =
                'am\\nraw'
                ;
        """
        model = compile(grammar, 'start')
        print(model.pretty())
        self.assertEqual(trim(pretty), model.pretty())

    def test_any(self):
        grammar = """
            start = /./ 'xx' /./ /./ 'yy' $;
        """
        model = compile(grammar, 'start')
        ast = model.parse('1xx 2 yy')
        self.assertEqual(('1', 'xx', ' ', '2', 'yy'), ast)

    def test_constant(self):
        grammar = """
            start = ()
                _0:`0` _1:`+1` _n123:`-123`
                _xF:`0xF`
                _string:`string`
                _string_space:`'string space'`
                _true:`True` _false:`False`
                $;
        """

        model = compile(grammar)
        ast = model.parse('')

        self.assertEqual(ast._0, 0)
        self.assertEqual(ast._1, 1)
        self.assertEqual(ast._n123, -123)
        self.assertEqual(ast._xF, 0xF)
        self.assertEqual(ast._string, 'string')
        self.assertEqual(ast._string_space, 'string space')
        self.assertEqual(ast._true, True)
        self.assertEqual(ast._false, False)


def test_parse_hash():
    grammar = r"""
        @@comments :: /@@@@@@@/
        @@eol_comments :: /@@@@@@@/

        start = '#' ;
    """

    parser = compile(grammar, eol_comments='')
    parser.parse('#', trace=True)


def test_parse_void():
    grammar = r"""
        start = () $ ;
    """

    ast = tool.parse(grammar, '')
    print(ast)
    assert ast is None


def test_no_default_comments():
    grammar = """
        start = 'a' $;
    """

    text = """
        # no comments are valid
        a
    """
    with pytest.raises(FailedToken):
        tool.parse(grammar, text)


import re


@pytest.mark.parametrize(
    "comment,option",
    [
        pytest.param(
            "# This comment should be stripped",
            {
                "eol_comments_re": re.compile(r"(?m)#.*?$"),
                "eol_comments": r"(?m)#.*?$",
            },
            id="eol_comments override",
        ),
        pytest.param(
            "(* This comment should be stripped *)",
            {
                "comments_re": re.compile(r"(?sm)[(][*](?:.|\n)*?[*][)]"),
                "comments": r"(?sm)[(][*](?:.|\n)*?[*][)]",
            },
            id="comments override",
        ),
    ],
)
def test_deprecated_comments_override_failures(comment, option):
    """
    # TODO: remove this test after {eol_}comments_re are no longer supported
    """
    grammar = """
        @@comments :: /@@@@@@/
        @@eol_comments :: /@@@@@@/

        start = 'a' $;
    """

    text = f"""
        {comment}
        a
    """
    with pytest.raises(AttributeError):
        tool.parse(grammar, text, **option)