from copy import deepcopy
from itertools import product

from pythonforandroid.logger import info
from pythonforandroid.recipe import Recipe
from pythonforandroid.bootstrap import Bootstrap
from pythonforandroid.util import BuildInterruptingException


def fix_deplist(deps):
    """ Turn a dependency list into lowercase, and make sure all entries
        that are just a string become a tuple of strings
    """
    deps = [
        ((dep.lower(),)
         if not isinstance(dep, (list, tuple))
         else tuple([dep_entry.lower()
                     for dep_entry in dep
                    ]))
        for dep in deps
    ]
    return deps


class RecipeOrder(dict):
    def __init__(self, ctx):
        self.ctx = ctx

    def conflicts(self):
        for name in self.keys():
            try:
                recipe = Recipe.get_recipe(name, self.ctx)
                conflicts = [dep.lower() for dep in recipe.conflicts]
            except ValueError:
                conflicts = []

            if any([c in self for c in conflicts]):
                return True
        return False


def get_dependency_tuple_list_for_recipe(recipe, blacklist=None):
    """ Get the dependencies of a recipe with filtered out blacklist, and
        turned into tuples with fix_deplist()
    """
    if blacklist is None:
        blacklist = set()
    assert(type(blacklist) == set)
    if recipe.depends is None:
        dependencies = []
    else:
        # Turn all dependencies into tuples so that product will work
        dependencies = fix_deplist(recipe.depends)

        # Filter out blacklisted items and turn lowercase:
        dependencies = [
            tuple(set(deptuple) - blacklist)
            for deptuple in dependencies
            if tuple(set(deptuple) - blacklist)
        ]
    return dependencies


def recursively_collect_orders(
        name, ctx, all_inputs, orders=None, blacklist=None
        ):
    '''For each possible recipe ordering, try to add the new recipe name
    to that order. Recursively do the same thing with all the
    dependencies of each recipe.

    '''
    name = name.lower()
    if orders is None:
        orders = []
    if blacklist is None:
        blacklist = set()
    try:
        recipe = Recipe.get_recipe(name, ctx)
        dependencies = get_dependency_tuple_list_for_recipe(
            recipe, blacklist=blacklist
        )

        # handle opt_depends: these impose requirements on the build
        # order only if already present in the list of recipes to build
        dependencies.extend(fix_deplist(
            [[d] for d in recipe.get_opt_depends_in_list(all_inputs)
             if d.lower() not in blacklist]
        ))

        if recipe.conflicts is None:
            conflicts = []
        else:
            conflicts = [dep.lower() for dep in recipe.conflicts]
    except ValueError:
        # The recipe does not exist, so we assume it can be installed
        # via pip with no extra dependencies
        dependencies = []
        conflicts = []

    new_orders = []
    # for each existing recipe order, see if we can add the new recipe name
    for order in orders:
        if name in order:
            new_orders.append(deepcopy(order))
            continue
        if order.conflicts():
            continue
        if any([conflict in order for conflict in conflicts]):
            continue

        for dependency_set in product(*dependencies):
            new_order = deepcopy(order)
            new_order[name]