veekun_pokedex/pokedex/util/movesets.py

#! /usr/bin/env python
# Encoding: UTF-8

import sys
import argparse
import itertools
from collections import defaultdict

from sqlalchemy.orm import aliased
from sqlalchemy.orm.exc import NoResultFound
from sqlalchemy.sql.expression import not_, and_, or_

from pokedex.db import connect, tables, util

from pokedex.util import querytimer
from pokedex.util.astar import a_star

class IllegalMoveCombination(ValueError): pass
class TooManyMoves(IllegalMoveCombination): pass
class NoMoves(IllegalMoveCombination): pass
class MovesNotLearnable(IllegalMoveCombination): pass
class NoParent(IllegalMoveCombination): pass
class TargetExcluded(IllegalMoveCombination): pass

def powerset(iterable):
    # recipe from: http://docs.python.org/library/itertools.html
    "powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
    s = list(iterable)
    return itertools.chain.from_iterable(itertools.combinations(s, r)
            for r in range(len(s)+1))

class MovesetSearch(object):
    def __init__(self, session, pokemon, version, moves, level=100, costs=None,
            exclude_versions=(), exclude_pokemon=(), debug=False):

        self.generator = self.error = None

        if not moves:
            self.error = NoMoves('No moves specified.')
            return
        elif len(moves) > 4:
            self.error = NoMoves('Too many moves specified.')
            return

        self.debug = debug

        self.session = session

        self.sketch = util.get(session, tables.Move, identifier=u'sketch').id
        self.no_eggs_group = util.get(session, tables.EggGroup,
                identifier=u'no-eggs').id
        self.ditto_group = util.get(session, tables.EggGroup,
                identifier=u'ditto').id

        if costs is None:
            self.costs = default_costs
        else:
            self.costs = costs

        self.excluded_families = frozenset(p.evolution_chain_id
                for p in exclude_pokemon)

        if pokemon:
            self.goal_evolution_chain = pokemon.evolution_chain_id
            if self.goal_evolution_chain in self.excluded_families:
                self.error = TargetExcluded('The target pokemon was excluded.')
                return
        else:
            self.goal_evolution_chain = None

        if debug:
            print 'Specified moves:', [move.id for move in moves]

        self.goal_moves = frozenset(move.id for move in moves)
        self.goal_version_group = version.version_group_id

        self.load_pokemon()

        # Fill self.generation_id_by_version_group
        self.load_version_groups(version.version_group_id,
                [v.version_group_id for v in exclude_versions])

        self.pokemon_moves = defaultdict(  # key: pokemon
                lambda: defaultdict(  # key: move
                    lambda: defaultdict(  # key: version_group
                        lambda: defaultdict(  # key: method
                            list))))  # list of (level, cost)
        self.movepools = defaultdict(dict)  # evo chain -> move -> best cost
        self.learnpools = defaultdict(set)  # evo chain -> move, w/o egg moves

        easy_moves, non_egg_moves = self.load_pokemon_moves(
                self.goal_evolution_chain, 'family')

        hard_moves = self.goal_moves - easy_moves
        self.egg_moves = self.goal_moves - non_egg_moves
        if hard_moves:
            # Have to breed!
            self.load_pokemon_moves(self.goal_evolution_chain, 'others')

        self.construct_breed_graph()

    def load_version_groups(self, version, excluded):
        """Load generation_id_by_version_group
        """
        query = self.session.query(tables.VersionGroup.id,
                tables.VersionGroup.generation_id)
        query = query.join(tables.Version.version_group)
        if excluded:
            query = query.filter(not_(tables.VersionGroup.id.in_(excluded)))
        self.generation_id_by_version_group = dict(query)
        def expand(v2):
            for v1 in self.generation_id_by_version_group:
                if self.trade_cost(v1, v2):
                    yield 0, None, v1
        def is_goal(v):
            return True
        goal = self.goal_version_group
        filtered_map = {goal: self.generation_id_by_version_group[goal]}
        for result in a_star(self.goal_version_group, expand, is_goal):
            for cost, transition, version in result:
                filtered_map[version] = (
                        self.generation_id_by_version_group[version])
        self.generation_id_by_version_group = filtered_map
        if self.debug:
            print 'Excluded version groups:', excluded
            print 'Trade cost table:'
            print '%03s' % '',
            for g1 in sorted(self.generation_id_by_version_group):
                print '%03s' % g1,
            print
            for g1 in sorted(self.generation_id_by_version_group):
                print '%03s' % g1,
                for g2 in sorted(self.generation_id_by_version_group):
                    print '%03s' % (self.trade_cost(g1, g2) or '---'),
                print

    def load_pokemon_moves(self, evolution_chain, selection):
        """Load pokemon_moves, movepools, learnpools, smeargle_families

        `selection`:
            'family' for loading only pokemon in evolution_chain
            'others' for loading only pokemon NOT in evolution_chain

        Returns: (easy_moves, non_egg_moves)
        If `selection` == 'family':
            easy_moves is a set of moves that are easier to obtain than by
                breeding
            non_egg_moves is a set of moves that don't require breeding
        Otherwise, these are empty sets.
        """
        if self.debug:
            print 'Loading moves, c%s %s' % (evolution_chain, selection)
        query = self.session.query(
                tables.PokemonMove.pokemon_id,
                tables.PokemonMove.move_id,
                tables.PokemonMove.version_group_id,
                tables.PokemonMoveMethod.identifier,
                tables.PokemonMove.level,
                tables.Pokemon.evolution_chain_id,
            )
        query = query.join(tables.PokemonMove.pokemon)
        query = query.filter(tables.PokemonMoveMethod.id == 
                tables.PokemonMove.pokemon_move_method_id)
        query = query.filter(tables.PokemonMove.version_group_id.in_(
                set(self.generation_id_by_version_group)))
        query = query.filter(or_(
                    tables.PokemonMove.level > 100,  # XXX: Chaff?
                    tables.PokemonMove.move_id.in_(self.goal_moves),
                    tables.PokemonMove.move_id == self.sketch,
                    tables.PokemonMove.move_id.in_(
                            self.evolution_moves.values()),
                ))
        if self.excluded_families:
            query = query.filter(not_(tables.Pokemon.evolution_chain_id.in_(
                    self.excluded_families)))
        if evolution_chain:
            if selection == 'family':
                query = query.filter(tables.Pokemon.evolution_chain_id == (
                        evolution_chain))
            elif selection == 'others':
                query = query.filter(tables.Pokemon.evolution_chain_id != (
                        evolution_chain))
        query = query.order_by(tables.PokemonMove.level)
        easy_moves = set()
        non_egg_moves = set()
        self.smeargle_families = set()
        for pokemon, move, vg, method, level, chain in query:
            if move in self.goal_moves or move == self.sketch:
                cost = self.learn_cost(method, vg)
                self.movepools[chain][move] = min(
                        self.movepools[chain].get(move, cost), cost)
                if method != 'egg':
                    self.learnpools[chain].add(move)
                    non_egg_moves.add(move)
                    if cost < self.costs['breed']:
                        easy_moves.add(move)
            else:
                cost = -1
            if move == self.sketch:
                self.smeargle_families.add(self.evolution_chains[pokemon])
            self.pokemon_moves[pokemon][move][vg][method].append((level, cost))
        if self.debug and selection == 'family':
            print 'Easy moves:', sorted(easy_moves)
            print 'Non-egg moves:', sorted(non_egg_moves)
        if self.debug:
            print 'Smeargle families:', sorted(self.smeargle_families)
        return easy_moves, non_egg_moves

    def learn_cost(self, method, version_group):
        """Return cost of learning a move by method (identifier) in ver. group
        """
        if method == 'level-up':
            return self.costs['level-up']
        gen = self.generation_id_by_version_group[version_group]
        if method == 'machine' and gen < 5:
            return self.costs['machine-once']
        elif method == 'tutor' and gen == 3:
            return self.costs['tutor-once']
        elif method == 'egg':
            return self.costs['breed']
        else:
            return self.costs[method]

    def trade_cost(self, version_group_from, version_group_to, *thing_generations):
        """Return cost of trading between versions, None if impossibble

        `thing_generations` should be the generation IDs of the pokemon and
        moves being traded.
        """
        # XXX: this ignores HM transfer restrictions
        gen_from = self.generation_id_by_version_group[version_group_from]
        gen_to = self.generation_id_by_version_group[version_group_to]
        if gen_from == gen_to:
            return self.costs['trade']
        elif any(gen > gen_to for gen in thing_generations):
            return None
        elif gen_from in (1, 2):
            if gen_to in (1, 2):
                return self.costs['trade']
            else:
                return None
        elif gen_to in (1, 2):
            return None
        elif gen_from > gen_to:
            return None
        elif gen_from < gen_to - 1:
            return None
        else:
            return self.costs['trade'] + self.costs['transfer']

    def load_pokemon(self):
        """Load pokemon breed groups and evolutions

        self.egg_groups: maps evolution chains to their sorted egg groups
            (wil contain empty tuple for no-eggs or ditto)
        self.evolution_chains: maps pokemon to their evolution chains
        self.pokemon_by_evolution_chain: maps evolution chains to their pokemon
        self.unbreedable: set of unbreedable pokemon

        self.evolution_parents: maps pokemon to their pre-evolved form
        self.evolutions: maps pokemon to lists of (trigger, move, level, child)
        self.evolution_moves: maps evolution_chains to their evolution moves
        """
        eg1 = tables.PokemonEggGroup
        eg2 = aliased(tables.PokemonEggGroup)
        query = self.session.query(
                tables.Pokemon.id,
                tables.Pokemon.evolution_chain_id,
                tables.Pokemon.evolves_from_pokemon_id,
                eg1.egg_group_id,
                eg2.egg_group_id,
            )
        query = query.join((eg1, eg1.pokemon_id == tables.Pokemon.id))
        query = query.outerjoin((eg2, and_(
                eg2.pokemon_id == tables.Pokemon.id,
                eg1.egg_group_id < eg2.egg_group_id,
            )))
        bad_groups = (self.no_eggs_group, self.ditto_group)
        unbreedable = set()
        self.evolution_parents = dict()
        self.egg_groups = defaultdict(tuple)
        self.evolution_chains = dict()
        self.pokemon_by_evolution_chain = defaultdict(set)
        for pokemon, evolution_chain, parent, g1, g2 in query:
            if g1 in bad_groups:
                unbreedable.add(pokemon)
            else:
                new_groups = (g1, g2) if g2 else (g1, )
                if len(self.egg_groups.get(evolution_chain, ())) <= len(new_groups):
                    self.egg_groups[evolution_chain] = new_groups
            self.evolution_chains[pokemon] = evolution_chain
            self.pokemon_by_evolution_chain[evolution_chain].add(pokemon)
            if parent:
                self.evolution_parents[pokemon] = parent
        self.unbreedable = frozenset(unbreedable)

        self.evolutions = defaultdict(set)
        self.evolution_moves = dict()
        query = self.session.query(
                tables.PokemonEvolution.evolved_pokemon_id,
                tables.EvolutionTrigger.identifier,
                tables.PokemonEvolution.known_move_id,
                tables.PokemonEvolution.minimum_level,
            )
        query = query.join(tables.PokemonEvolution.trigger)
        for child, trigger, move, level in query:
            self.evolutions[self.evolution_parents[child]].add(
                    (trigger, move, level, child))
            if move:
                self.evolution_moves[self.evolution_chains[child]] = move

        if self.debug:
            print 'Loaded %s pokemon: %s evo; %s families: %s breedable' % (
                    len(self.evolution_chains),
                    len(self.pokemon_by_evolution_chain),
                    len(self.egg_groups),
                    len(self.evolutions),
                )
            print 'Evolution moves: %s' % self.evolution_moves

    def construct_breed_graph(self):
        """Fills breeds_required

        breeds_required[egg_group][moveset] = minimum number of breeds needed
            from a pokemon in this group with this moveset to the goal pokemon
            with the goal moveset.
            The score cannot get lower by learning new moves, only by breeding.
            If missing, breeding or raising the pokemon won't do any good.
            For pokemon in the target family, breeds_required doesn't apply.
        """

        # Part I. Determining what moves can be passed/learned

        # eg1_movepools[egg_group_id] = set of moves passable by pkmn in that group
        eg1_movepools = defaultdict(set)
        # eg2_movepools[b_g_id1, b_g_id2] = ditto for pkmn in *both* groups
        eg2_movepools = defaultdict(set)
        # non_egg_pools = as eg1_movepools but for *learnable* moves
        learn_pools = defaultdict(set)

        goal_egg_groups = self.egg_groups[self.goal_evolution_chain]
        all_groups = set()

        for family, groups in self.egg_groups.iteritems():
            if not groups:
                continue
            if family == self.goal_evolution_chain:
                continue
            elif family in self.smeargle_families:
                pool = self.goal_moves
            else:
                pool = self.movepools[family]
                pool = set(pool) & self.goal_moves
            learnpool = self.learnpools[family] & pool
            for group in groups:
                eg1_movepools[group].update(pool)
                learn_pools[group].update(learnpool)
                all_groups.add(group)
            if len(groups) >= 2:
                eg2_movepools[groups].update(pool)

        if self.debug:
            for group in sorted(all_groups):
                print "%2s can pass: %s" % (group, sorted(eg1_movepools[group]))
                if learn_pools[group] != eg1_movepools[group]:
                    print "  but learn: %s" % sorted(learn_pools[group])
            for g2 in sorted(all_groups):
                for g1 in sorted(all_groups):
                    if eg2_movepools[g1, g2]:
                        print " %2s/%2s pass: %s" % (g1, g2, sorted(eg2_movepools[g1, g2]))
            print 'Goal groups:', goal_egg_groups

        # Part II. Determining which moves are worthwhile to pass

        # We want *all* paths, not just shortest ones, so use DFS.
        breeds_required = defaultdict(dict)
        def handle(group, moves, path):
            """
            group: the group of the parent
            moves: moves the parent should pass down
            path: previously visited groups - to prevent cycles
            """
            if not moves:
                # No more moves needed to pass down: success!
                return True
            if breeds_required[group].get(moves, 999) <= len(path):
                # Already done
                return True
            success = False
            # Breed some more
            path = path + (group, )
            for new_group in all_groups.difference(path):
                new_groups = tuple(sorted([group, new_group]))
                # Can we pass down all the requested moves?
                if moves.issubset(eg1_movepools[new_group]):
                    # Learn some of the moves: they don't have to be passed to us
                    for learned in powerset(moves & learn_pools[new_group]):
                        new_moves = moves.difference(learned)
                        local_success = handle(new_group, new_moves, path)
                        # If this chain eventually ended up being successful,
                        # it means that it is useful to pass this moveset
                        # to this group.
                        if local_success:
                            breeds_required[group][moves] = min(breeds_required[group].get(moves, 999), len(path) - 1)
                            success = True
            return success
        for group in goal_egg_groups:
            handle(group, self.goal_moves, ())
            for moves in powerset(self.goal_moves.difference(self.egg_moves)):
                if moves:
                    breeds_required[group][frozenset(moves) | self.egg_moves] = 1
        self.breeds_required = breeds_required

        if self.debug:
            for group, movesetlist in breeds_required.items():
                print 'From egg group', group
                for moveset, cost in movesetlist.items():
                    print "   %s breeds with %s" % (cost, sorted(moveset))

default_costs = {
    # Costs for learning a move in verious ways
    'level-up': 20,  # The normal way
    'machine': 40,  # Machines are slightly inconvenient.
    'machine-once': 2000,  # before gen. 5, TMs only work once. Avoid.
    'tutor': 60,  # Tutors are slightly more inconvenient than TMs – can't carry them around
    'tutor-once': 2100,  # gen III: tutors only work once (well except Emerald frontier ones)
    'sketch': 10,  # Quite cheap. (Doesn't include learning Sketch itself)

    # Gimmick moves – we need to use this method to learn the move anyway,
    # so make a big-ish dent in the score if missing
    'stadium-surfing-pikachu': 100,
    'light-ball-egg': 100,  #  … 

    # Ugh... I don't know?
    'colosseum-purification': 100,
    'xd-shadow': 100,
    'xd-purification': 100,
    'form-change': 100,

    # Other actions.
    # Breeding should cost more than 3 times than a lv-up/machine/tutor move.
    'evolution': 100,  # We have to do this anyway, usually.
    'evolution-delayed': 50,  # *in addition* to evolution. Who wants to mash B on every level.
    'breed': 400,  # Breeding's a pain.
    'trade': 200,  # Trading's a pain, but not as much as breeding.
    'transfer': 200,  # *in addition* to trade. For one-way cross-generation transfers
    'delete': 300,  # Deleting a move. (Not needed unless deleting an evolution move.)
    'relearn': 150,  # Also a pain, though not as big as breeding.
    'per-level': 1,  # Prefer less grinding. This is for all lv-ups but the final “grow”
}

def main(argv):
    parser = argparse.ArgumentParser(description=
        'Find out if the specified moveset is valid, and provide a suggestion '
        'on how to obtain it.')

    parser.add_argument('pokemon', metavar='POKEMON', type=unicode,
        help='Pokemon to check the moveset for')

    parser.add_argument('move', metavar='MOVE', type=unicode, nargs='*',
        help='Moves in the moveset')

    parser.add_argument('-l', '--level', metavar='LV', type=int, default=100,
        help='Level of the pokemon')

    parser.add_argument('-v', '--version', metavar='VER', type=unicode,
        default='black',
        help='Version to search in.')

    parser.add_argument('-V', '--exclude-version', metavar='VER', type=unicode,
        action='append', default=[],
        help='Versions to exclude (along with their '
            'counterparts, if any, e.g. `black` will also exclude White).')

    parser.add_argument('-P', '--exclude-pokemon', metavar='PKM', type=unicode,
        action='append', default=[],
        help='Pokemon to exclude (along with their families, e.g. `pichu` '
            'will also exclude Pikachu and Raichu).')

    parser.add_argument('-d', '--debug', action='append_const', const=1,
        default=[],
        help='Output timing and debugging information (can be specified more '
            'than once).')

    args = parser.parse_args(argv)
    args.debug = len(args.debug)

    if args.debug:
        print 'Connecting'

    session = connect(engine_args={'echo': args.debug > 1})

    if args.debug:
        print 'Parsing arguments'

    def _get_list(table, idents, name):
        result = []
        for ident in idents:
            try:
                result.append(util.get(session, table, identifier=ident))
            except NoResultFound:
                print>>sys.stderr, ('%s %s not found. Please use '
                        'the identifier.' % (name, ident))
                return 2
        return result

    pokemon = _get_list(tables.Pokemon, [args.pokemon], 'Pokemon')[0]
    moves = _get_list(tables.Move, args.move, 'Move')
    version = _get_list(tables.Version, [args.version], 'Version')[0]
    excl_versions = _get_list(tables.Version, args.exclude_version, 'Version')
    excl_pokemon = _get_list(tables.Pokemon, args.exclude_pokemon, 'Pokemon')

    if args.debug:
        print 'Starting search'

    search = MovesetSearch(session, pokemon, version, moves, args.level,
        exclude_versions=excl_versions, exclude_pokemon=excl_pokemon,
        debug=args.debug)

    if search.error:
        print 'Error:', search.error
        return 1

    if args.debug:
        print 'Done'

if __name__ == '__main__':
    sys.exit(main(sys.argv[1:]))