# Copyright 2006 Google, Inc. All Rights Reserved.

# Licensed to PSF under a Contributor Agreement.

"""Fixer for apply().

This converts apply(func, v, k) into (func)(*v, **k)."""

# Local imports

from .. import pytree

from ..pgen2 import token

from .. import fixer_base

from ..fixer_util import Call, Comma

class FixApply(fixer_base.BaseFix):

    PATTERN = """

    power< 'apply'

        trailer<

            '('

            arglist<

                (not argument<NAME '=' any>) func=any ','

                (not argument<NAME '=' any>) args=any [','

                (not argument<NAME '=' any>) kwds=any] [',']

            >

            ')'

        >

    >

    """

    def transform(self, node, results):

        syms = self.syms

        assert results

        func = results["func"]

        args = results["args"]

        kwds = results.get("kwds")

        prefix = node.get_prefix()

        func = func.clone()

        if (func.type not in (token.NAME, syms.atom) and

            (func.type != syms.power or

             func.children[-2].type == token.DOUBLESTAR)):

            # Need to parenthesize

            func = self.parenthesize(func)

        func.set_prefix("")

        args = args.clone()

        args.set_prefix("")

        if kwds is not None:

            kwds = kwds.clone()

            kwds.set_prefix("")

        l_newargs = [pytree.Leaf(token.STAR, "*"), args]

        if kwds is not None:

            l_newargs.extend([Comma(),

                              pytree.Leaf(token.DOUBLESTAR, "**"),

                              kwds])

            l_newargs[-2].set_prefix(" ") # that's the ** token

        # XXX Sometimes we could be cleverer, e.g. apply(f, (x, y) + t)

        # can be translated into f(x, y, *t) instead of f(*(x, y) + t)

        #new = pytree.Node(syms.power, (func, ArgList(l_newargs)))

        return Call(func, l_newargs, prefix=prefix)