from collections import defaultdict

from jedi._compatibility import zip_longest
from jedi import debug
from jedi import common
from jedi.parser import tree
from jedi.evaluate import iterable
from jedi.evaluate import analysis
from jedi.evaluate import context


def try_iter_content(types, depth=0):
    """Helper method for static analysis."""
    if depth > 10:
        # It's possible that a loop has references on itself (especially with
        # CompiledObject). Therefore don't loop infinitely.
        return

    for typ in types:
        try:
            f = typ.py__iter__
        except AttributeError:
            pass
        else:
            for iter_types in f():
                try_iter_content(iter_types, depth + 1)


class AbstractArguments():
    context = None

    def eval_argument_clinic(self, parameters):
        """Uses a list with argument clinic information (see PEP 436)."""
        iterator = self.unpack()
        for i, (name, optional, allow_kwargs) in enumerate(parameters):
            key, argument = next(iterator, (None, None))
            if key is not None:
                raise NotImplementedError
            if argument is None and not optional:
                debug.warning('TypeError: %s expected at least %s arguments, got %s',
                              name, len(parameters), i)
                raise ValueError
            values = set() if argument is None else argument.infer()

            if not values and not optional:
                # For the stdlib we always want values. If we don't get them,
                # that's ok, maybe something is too hard to resolve, however,
                # we will not proceed with the evaluation of that function.
                debug.warning('argument_clinic "%s" not resolvable.', name)
                raise ValueError
            yield values

    def eval_args(self):
        # TODO this method doesn't work with named args and a lot of other
        # things. Use unpack.
        raise DeprecationWarning
        return [self._evaluator.eval_element(self.context, el) for stars, el in self._split()]

    def eval_all(self, func=None):
        """
        Evaluates all arguments as a support for static analysis
        (normally Jedi).
        """
        raise DeprecationWarning
        for key, element_values in self.unpack():
            for element in element_values:
                types = self._evaluator.eval_element(self.context, element)
                try_iter_content(types)


class TreeArguments(AbstractArguments):
    def __init__(self, evaluator, context, argument_node, trailer=None):
        """
        The argument_node is either a parser node or a list of evaluated
        objects. Those evaluated objects may be lists of evaluated objects
        themselves (one list for the first argument, one for the second, etc).

        :param argument_node: May be an argument_node or a list of nodes.
        """
        self.argument_node = argument_node
        self.context = context
        self._evaluator = evaluator
        self.trailer = trailer  # Can be None, e.g. in a class definition.

    def _split(self):
        if isinstance(self.argument_node, (tuple, list)):
            for el in self.argument_node:
                yield 0, el
        else:
            if not (tree.is_node(self.argument_node, 'arglist') or (
                    # in python 3.5 **arg is an argument, not arglist
                    (tree.is_node(self.argument_node, 'argument') and
                     self.argument_node.children[0] in ('*', '**')))):
                yield 0, self.argument_node
                return

            iterator = iter(self.argument_node.children)
            for child in iterator:
                if child == ',':
                    continue
                elif child in ('*', '**'):
                    yield len(child.value), next(iterator)
                elif tree.is_node(child, 'argument') and \
                        child.children[0] in ('*', '**'):
                    assert len(child.children) == 2
                    yield len(child.children[0].value), child.children[1]
                else:
                    yield 0, child

    def unpack(self, func=None):
        named_args = []
        for stars, el in self._split():
            if stars == 1:
                arrays = self.context.eval_node(el)
                iterators = [_iterate_star_args(self._evaluator, a, el, func)
                             for a in arrays]
                iterators = list(iterators)
                for values in list(zip_longest(*iterators)):
                    # TODO zip_longest yields None, that means this would raise
                    # an exception?
                    yield None, context.get_merged_lazycontext(values)
            elif stars == 2:
                arrays = self._evaluator.eval_element(self.context, el)
                for dct in arrays:
                    for key, values in _star_star_dict(self._evaluator, dct, el, func):
                        yield key, values
            else:
                if tree.is_node(el, 'argument'):
                    c = el.children
                    if len(c) == 3:  # Keyword argument.
                        named_args.append((c[0].value, context.LazyTreeContext(self.context, c[2]),))
                    else:  # Generator comprehension.
                        # Include the brackets with the parent.
                        comp = iterable.GeneratorComprehension(
                            self._evaluator, self.argument_node.parent)
                        yield None, context.LazyKnownContext(comp)
                else:
                    yield None, context.LazyTreeContext(self.context, el)

        # Reordering var_args is necessary, because star args sometimes appear
        # after named argument, but in the actual order it's prepended.
        for named_arg in named_args:
            yield named_arg

    def as_tuple(self):
        raise DeprecationWarning
        for stars, argument in self._split():
            if tree.is_node(argument, 'argument'):
                argument, default = argument.children[::2]
            else:
                default = None
            yield argument, default, stars

    def __repr__(self):
        return '<%s: %s>' % (self.__class__.__name__, self.argument_node)

    def get_calling_var_args(self):
        return _get_calling_var_args(self._evaluator, self)


class ValuesArguments(AbstractArguments):
    def __init__(self, values_list):
        self._values_list = values_list

    def unpack(self, func=None):
        for values in self._values_list:
            yield None, context.LazyKnownContexts(values)

    def get_calling_var_args(self):
        return None

    def __repr__(self):
        return '<%s: %s>' % (self.__class__.__name__, self._values_list)


class ExecutedParam(object):
    """Fake a param and give it values."""
    def __init__(self, original_param, var_args, lazy_context):
        self._original_param = original_param
        self.var_args = var_args
        self._lazy_context = lazy_context
        self.string_name = self._original_param.name.value

    def infer(self):
        return self._lazy_context.infer()

    @property
    def position_nr(self):
        # Need to use the original logic here, because it uses the parent.
        return self._original_param.position_nr

    def __repr__(self):
        return '<%s: %s>' % (self.__class__.__name__, self.string_name)


def _get_calling_var_args(evaluator, var_args):
    old_var_args = None
    while var_args != old_var_args:
        old_var_args = var_args
        continue#TODO REMOVE
        for name, default, stars in reversed(list(var_args.as_tuple())):
            if not stars or not isinstance(name, tree.Name):
                continue

            names = evaluator.goto(name)
            if len(names) != 1:
                break
            param = names[0].get_definition()
            if not isinstance(param, ExecutedParam):
                if isinstance(param, tree.Param):
                    # There is no calling var_args in this case - there's just
                    # a param without any input.
                    return None
                break
            # We never want var_args to be a tuple. This should be enough for
            # now, we can change it later, if we need to.
            if isinstance(param.var_args, Arguments):
                var_args = param.var_args
    return var_args.argument_node or var_args.trailer


def get_params(evaluator, parent_context, func, var_args):
    result_params = []
    param_dict = {}
    for param in func.params:
        param_dict[str(param.name)] = param
    unpacked_va = list(var_args.unpack(func))
    var_arg_iterator = common.PushBackIterator(iter(unpacked_va))

    non_matching_keys = defaultdict(lambda: [])
    keys_used = {}
    keys_only = False
    had_multiple_value_error = False
    for param in func.params:
        # The value and key can both be null. There, the defaults apply.
        # args / kwargs will just be empty arrays / dicts, respectively.
        # Wrong value count is just ignored. If you try to test cases that are
        # not allowed in Python, Jedi will maybe not show any completions.
        key, argument = next(var_arg_iterator, (None, None))
        while key is not None:
            keys_only = True
            try:
                key_param = param_dict[key]
            except KeyError:
                non_matching_keys[key] = argument
            else:
                if key in keys_used:
                    had_multiple_value_error = True
                    m = ("TypeError: %s() got multiple values for keyword argument '%s'."
                         % (func.name, key))
                    calling_va = _get_calling_var_args(evaluator, var_args)
                    if calling_va is not None:
                        analysis.add(evaluator, 'type-error-multiple-values',
                                     calling_va, message=m)
                else:
                    keys_used[key] = ExecutedParam(key_param, var_args, argument)
            key, argument = next(var_arg_iterator, (None, None))

        try:
            result_params.append(keys_used[param.name.value])
            continue
        except KeyError:
            pass

        if param.stars == 1:
            # *args param
            lazy_context_list = []
            if argument is not None:
                lazy_context_list.append(argument)
                for key, argument in var_arg_iterator:
                    # Iterate until a key argument is found.
                    if key:
                        var_arg_iterator.push_back((key, argument))
                        break
                    lazy_context_list.append(argument)
            seq = iterable.FakeSequence(evaluator, 'tuple', lazy_context_list)
            result_arg = context.LazyKnownContext(seq)
        elif param.stars == 2:
            # **kwargs param
            dct = iterable.FakeDict(evaluator, dict(non_matching_keys))
            result_arg = context.LazyKnownContext(dct)
            non_matching_keys = {}
        else:
            # normal param
            if argument is None:
                # No value: Return an empty container
                if param.default is None:
                    result_arg = context.LazyUnknownContext()
                else:
                    result_arg = context.LazyTreeContext(parent_context, param.default)
                if not keys_only:
                    calling_va = var_args.get_calling_var_args()
                    if calling_va is not None:
                        m = _error_argument_count(func, len(unpacked_va))
                        analysis.add(evaluator, 'type-error-too-few-arguments',
                                     calling_va, message=m)
            else:
                result_arg = argument

        result_params.append(ExecutedParam(param, var_args, result_arg))
        keys_used[param.name.value] = result_params[-1]

    if keys_only:
        # All arguments should be handed over to the next function. It's not
        # about the values inside, it's about the names. Jedi needs to now that
        # there's nothing to find for certain names.
        for k in set(param_dict) - set(keys_used):
            param = param_dict[k]

            if not (non_matching_keys or had_multiple_value_error or
                    param.stars or param.default):
                # add a warning only if there's not another one.
                calling_va = _get_calling_var_args(evaluator, var_args)
                if calling_va is not None:
                    m = _error_argument_count(func, len(unpacked_va))
                    analysis.add(evaluator, 'type-error-too-few-arguments',
                                 calling_va, message=m)

    for key, argument in non_matching_keys.items():
        m = "TypeError: %s() got an unexpected keyword argument '%s'." \
            % (func.name, key)
        analysis.add(evaluator, 'type-error-keyword-argument', argument.whatever, message=m)

    remaining_arguments = list(var_arg_iterator)
    if remaining_arguments:
        m = _error_argument_count(func, len(unpacked_va))
        # Just report an error for the first param that is not needed (like
        # cPython).
        first_key, first_values = remaining_arguments[0]
        # TODO REENABLE
        for v in []:#first_values:
            if first_key is not None:
                # Is a keyword argument, return the whole thing instead of just
                # the value node.
                v = v.parent
                try:
                    non_kw_param = keys_used[first_key]
                except KeyError:
                    pass
                else:
                    origin_args = non_kw_param.parent.var_args.argument_node
                    # TODO  calculate the var_args tree and check if it's in
                    # the tree (if not continue).
                    # print('\t\tnonkw', non_kw_param.parent.var_args.argument_node, )
                    if origin_args not in [f.parent.parent for f in first_values]:
                        continue
            analysis.add(evaluator, 'type-error-too-many-arguments',
                         v, message=m)
    return result_params


def _iterate_star_args(evaluator, array, input_node, func=None):
    try:
        iter_ = array.py__iter__
    except AttributeError:
        if func is not None:
            # TODO this func should not be needed.
            m = "TypeError: %s() argument after * must be a sequence, not %s" \
                % (func.name.value, array)
            analysis.add(evaluator, 'type-error-star', input_node, message=m)
    else:
        for lazy_context in iter_():
            yield lazy_context


def _star_star_dict(evaluator, array, input_node, func):
    from jedi.evaluate.representation import Instance
    if isinstance(array, Instance) and array.name.get_code() == 'dict':
        # For now ignore this case. In the future add proper iterators and just
        # make one call without crazy isinstance checks.
        return {}
    elif isinstance(array, iterable.AbstractSequence) and array.array_type == 'dict':
        return array.exact_key_items()
    else:
        if func is not None:
            m = "TypeError: %s argument after ** must be a mapping, not %s" \
                % (func.name.value, array)
            analysis.add(evaluator, 'type-error-star-star', input_node, message=m)
        return {}


def _error_argument_count(func, actual_count):
    default_arguments = sum(1 for p in func.params if p.default or p.stars)

    if default_arguments == 0:
        before = 'exactly '
    else:
        before = 'from %s to ' % (len(func.params) - default_arguments)
    return ('TypeError: %s() takes %s%s arguments (%s given).'
            % (func.name, before, len(func.params), actual_count))


def create_default_param(parent_context, param):
    if param.stars == 1:
        result_arg = context.LazyKnownContext(
            iterable.FakeSequence(parent_context.evaluator, 'tuple', [])
        )
    elif param.stars == 2:
        result_arg = context.LazyKnownContext(
            iterable.FakeDict(parent_context.evaluator, {})
        )
    elif param.default is None:
        result_arg = context.LazyUnknownContext()
    else:
        result_arg = context.LazyTreeContext(parent_context, param.default)
    return ExecutedParam(param, None, result_arg)