veekun_pokedex/pokedex/struct/__init__.py
2012-10-13 16:15:37 +02:00

604 lines
20 KiB
Python

# encoding: utf8
u"""
Handles reading and encryption/decryption of Pokémon save file data.
See: http://projectpokemon.org/wiki/Pokemon_NDS_Structure
Kudos to LordLandon for his pkmlib.py, from which this module was originally
derived.
"""
import struct
from pokedex.db import tables
from pokedex.formulae import calculated_hp, calculated_stat
from pokedex.compatibility import namedtuple, permutations
from pokedex.struct._pokemon_struct import make_pokemon_struct
def pokemon_prng(seed):
u"""Creates a generator that simulates the main Pokémon PRNG."""
while True:
seed = 0x41C64E6D * seed + 0x6073
seed &= 0xFFFFFFFF
yield seed >> 16
def _struct_proxy(name):
def getter(self):
return getattr(self.structure, name)
def setter(self, value):
setattr(self.structure, name, value)
return property(getter, setter)
def _struct_frozenset_proxy(name):
def getter(self):
bitstruct = getattr(self.structure, name)
return frozenset(k for k, v in bitstruct.items() if v)
def setter(self, value):
bitstruct = dict((k, True) for k in value)
setattr(self.structure, name, bitstruct)
return property(getter, setter)
class SaveFilePokemon(object):
u"""Base class for an individual Pokémon, from the game's point of view.
Handles translating between the on-disk encrypted form, the in-RAM blob
(also used by pokesav), and something vaguely intelligible.
"""
Stat = namedtuple('Stat', ['stat', 'base', 'gene', 'exp', 'calc'])
def __init__(self, blob=None, encrypted=False, session=None):
u"""Wraps a Pokémon save struct in a friendly object.
If `encrypted` is True, the blob will be decrypted as though it were an
on-disk save. Otherwise, the blob is taken to be already decrypted and
is left alone.
`session` is an optional database session. Either give it or fill it
later with `use_database_session`
"""
try:
self.generation_id
except AttributeError:
raise NotImplementedError(
"Use generation-specific subclass of SaveFilePokemon")
if blob:
if encrypted:
# Decrypt it.
# Interpret as one word (pid), followed by a bunch of shorts
struct_def = "I" + "H" * ((len(blob) - 4) / 2)
shuffled = list( struct.unpack(struct_def, blob) )
# Apply standard Pokémon decryption, undo the block shuffling, and
# done
self.reciprocal_crypt(shuffled)
words = self.shuffle_chunks(shuffled, reverse=True)
self.blob = struct.pack(struct_def, *words)
else:
# Already decrypted
self.blob = blob
self.structure = self.pokemon_struct.parse(self.blob)
else:
self.structure = self.pokemon_struct.parse('\0' * (32 * 4 + 8))
if session:
self.use_database_session(session)
else:
self._session = None
@property
def as_struct(self):
u"""Returns a decrypted struct, aka .pkm file."""
return self.blob
@property
def as_encrypted(self):
u"""Returns an encrypted struct the game expects in a save file."""
# Interpret as one word (pid), followed by a bunch of shorts
struct_def = "I" + "H" * ((len(self.blob) - 4) / 2)
words = list( struct.unpack(struct_def, self.blob) )
# Apply the block shuffle and standard Pokémon encryption
shuffled = self.shuffle_chunks(words)
self.reciprocal_crypt(shuffled)
# Stuff back into a string, and done
return struct.pack(struct_def, *shuffled)
def export(self):
"""Exports the pokemon as a YAML/JSON-compatible dict
"""
st = self.structure
result = dict(
species=dict(id=self.species.id, name=self.species.name),
ability=dict(id=self.ability.id, name=self.ability.name),
)
result['original trainer'] = dict(
id=self.original_trainer_id,
secret=self.original_trainer_secret_id,
name=unicode(self.original_trainer_name),
gender=self.original_trainer_gender
)
if self.form != self.species.default_form:
result['form'] = dict(id=self.form.id, name=self.form.form_name)
if self.held_item:
result['item'] = dict(id=self.item.id, name=self.item.name)
if self.exp:
result['exp'] = self.exp
if self.happiness:
result['happiness'] = self.happiness
if self.markings:
result['markings'] = sorted(self.markings)
if self.original_country and self.original_country != '_unset':
result['original country'] = self.original_country
if self.original_version and self.original_version != '_unset':
result['original version'] = self.original_version
if self.encounter_type and self.encounter_type != '_unset':
result['encounter type'] = self.encounter_type
if self.nickname:
result['nickname'] = unicode(self.nickname)
if self.egg_location:
result['egg location'] = dict(id=self.egg_location.id,
name=self.egg_location.name)
if self.met_location:
result['met location'] = dict(id=self.egg_location.id,
name=self.met_location.name)
if self.date_egg_received:
result['egg received'] = self.date_egg_received.isoformat()
if self.date_met:
result['date met'] = self.date_met.isoformat()
if self.pokerus:
result['pokerus data'] = self.pokerus
if self.pokeball:
result['pokeball'] = dict(id=self.pokeball.id,
name=self.pokeball.name)
if self.met_at_level:
result['met at level'] = self.met_at_level
if not self.is_nicknamed:
result['not nicknamed'] = True
if self.is_egg:
result['is egg'] = True
if self.fateful_encounter:
result['fateful encounter'] = True
if self.gender != 'genderless':
result['gender'] = self.gender
moves = result['moves'] = []
for i, move_object in enumerate(self.moves, 1):
move = {}
if move_object:
move['id'] = move_object.id
move['name'] = move_object.name
pp = st['move%s_pp' % i]
if pp:
move['pp'] = pp
pp_up = st['move%s_pp_ups' % i]
if pp_up:
move['pp_up'] = pp_up
if move:
moves.append(move)
effort = {}
genes = {}
contest_stats = {}
for pokemon_stat in self._pokemon.stats:
stat_identifier = pokemon_stat.stat.identifier.replace('-', '_')
if st['iv_' + stat_identifier]:
genes[stat_identifier] = st['iv_' + stat_identifier]
if st['effort_' + stat_identifier]:
effort[stat_identifier] = st['effort_' + stat_identifier]
for contest_stat in 'cool', 'beauty', 'cute', 'smart', 'tough', 'sheen':
if st['contest_' + contest_stat]:
contest_stats[contest_stat] = st['contest_' + contest_stat]
if effort:
result['effort'] = effort
if genes:
result['genes'] = genes
if contest_stats:
result['contest_stats'] = contest_stats
ribbons = list(self.ribbons)
if ribbons:
result['ribbons'] = ribbons
return result
### Delicious data
@property
def is_shiny(self):
u"""Returns true iff this Pokémon is shiny."""
# See http://bulbapedia.bulbagarden.net/wiki/Personality#Shininess
# But don't see it too much, because the above is super over
# complicated. Do this instead!
personality_msdw = self.structure.personality >> 16
personality_lsdw = self.structure.personality & 0xffff
return (
self.structure.original_trainer_id
^ self.structure.original_trainer_secret_id
^ personality_msdw
^ personality_lsdw
) < 8
def use_database_session(self, session):
"""Remembers the given database session, and prefetches a bunch of
database stuff. Gotta call this (or give session to `__init__`) before
you use the database properties like `species`, etc.
"""
self._session = session
st = self.structure
if st.national_id:
self._pokemon = session.query(tables.Pokemon).get(st.national_id)
self._pokemon_form = session.query(tables.PokemonForm) \
.with_parent(self._pokemon) \
.filter_by(form_identifier=st.alternate_form) \
.one()
else:
self._pokemon = self._pokemon_form = None
self._ability = self._session.query(tables.Ability).get(st.ability_id)
if self._pokemon:
growth_rate = self._pokemon.species.growth_rate
self._experience_rung = session.query(tables.Experience) \
.filter(tables.Experience.growth_rate == growth_rate) \
.filter(tables.Experience.experience <= st.exp) \
.order_by(tables.Experience.level.desc()) \
[0]
level = self._experience_rung.level
self._next_experience_rung = None
if level < 100:
self._next_experience_rung = session.query(tables.Experience) \
.filter(tables.Experience.growth_rate == growth_rate) \
.filter(tables.Experience.level == level + 1) \
.one()
self._held_item = None
if st.held_item_id:
self._held_item = session.query(tables.ItemGameIndex) \
.filter_by(generation_id = 4, game_index = st.held_item_id).one().item
if self._pokemon:
self._stats = []
for pokemon_stat in self._pokemon.stats:
stat_identifier = pokemon_stat.stat.identifier.replace('-', '_')
gene = st['iv_' + stat_identifier]
exp = st['effort_' + stat_identifier]
if pokemon_stat.stat.identifier == u'hp':
calc = calculated_hp
else:
calc = calculated_stat
stat_tup = self.Stat(
stat = pokemon_stat.stat,
base = pokemon_stat.base_stat,
gene = gene,
exp = exp,
calc = calc(
pokemon_stat.base_stat,
level = level,
iv = gene,
effort = exp,
),
)
self._stats.append(stat_tup)
else:
self._stats = [0] * 6
move_ids = (
self.structure.move1_id,
self.structure.move2_id,
self.structure.move3_id,
self.structure.move4_id,
)
move_rows = self._session.query(tables.Move).filter(tables.Move.id.in_(move_ids))
moves_dict = dict((move.id, move) for move in move_rows)
self._moves = [moves_dict.get(move_id, None) for move_id in move_ids]
if st.hgss_pokeball >= 17:
pokeball_id = st.hgss_pokeball - 17 + 492
elif st.dppt_pokeball:
pokeball_id = st.dppt_pokeball
else:
pokeball_id = None
if pokeball_id:
self._pokeball = session.query(tables.ItemGameIndex) \
.filter_by(generation_id = 4, game_index = pokeball_id).one().item
egg_loc_id = st.pt_egg_location_id or st.dp_egg_location_id
met_loc_id = st.pt_met_location_id or st.dp_met_location_id
self._egg_location = None
if egg_loc_id:
self._egg_location = session.query(tables.LocationGameIndex) \
.filter_by(generation_id = self.generation_id, game_index = egg_loc_id).one().location
if met_loc_id:
self._met_location = session.query(tables.LocationGameIndex) \
.filter_by(generation_id = self.generation_id, game_index = met_loc_id).one().location
else:
self._met_location = None
@property
def species(self):
return self._pokemon_form.species
@property
def pokemon(self):
return self._pokemon_form.pokemon
@property
def form(self):
return self._pokemon_form
@property
def species_form(self):
return self._pokemon_form
@property
def pokeball(self):
return self._pokeball
@property
def egg_location(self):
return self._egg_location
@property
def met_location(self):
return self._met_location
@property
def level(self):
return self._experience_rung.level
@property
def exp_to_next(self):
if self._next_experience_rung:
return self._next_experience_rung.experience - self.structure.exp
else:
return 0
@property
def progress_to_next(self):
if self._next_experience_rung:
return 1.0 \
* (self.structure.exp - self._experience_rung.experience) \
/ (self._next_experience_rung.experience - self._experience_rung.experience)
else:
return 0.0
@property
def ability(self):
return self._ability
@property
def held_item(self):
return self._held_item
@property
def stats(self):
return self._stats
@property
def moves(self):
return self._moves
@property
def move_pp(self):
return (
self.structure.move1_pp,
self.structure.move2_pp,
self.structure.move3_pp,
self.structure.move4_pp,
)
@property
def markings(self):
return frozenset(k for k, v in self.structure.markings.items() if v)
@markings.setter
def markings(self, value):
self.structure.markings = dict((k, True) for k in value)
original_trainer_id = _struct_proxy('original_trainer_id')
original_trainer_secret_id = _struct_proxy('original_trainer_secret_id')
original_trainer_name = _struct_proxy('original_trainer_name')
exp = _struct_proxy('exp')
happiness = _struct_proxy('happiness')
original_country = _struct_proxy('original_country')
is_nicknamed = _struct_proxy('is_nicknamed')
is_egg = _struct_proxy('is_egg')
fateful_encounter = _struct_proxy('fateful_encounter')
gender = _struct_proxy('gender')
original_version = _struct_proxy('original_version')
date_egg_received = _struct_proxy('date_egg_received')
date_met = _struct_proxy('date_met')
pokerus = _struct_proxy('pokerus')
met_at_level = _struct_proxy('met_at_level')
original_trainer_gender = _struct_proxy('original_trainer_gender')
encounter_type = _struct_proxy('encounter_type')
markings = _struct_frozenset_proxy('markings')
sinnoh_ribbons = _struct_frozenset_proxy('sinnoh_ribbons')
hoenn_ribbons = _struct_frozenset_proxy('hoenn_ribbons')
sinnoh_contest_ribbons = _struct_frozenset_proxy('sinnoh_contest_ribbons')
@property
def ribbons(self):
return frozenset(
self.sinnoh_ribbons |
self.hoenn_ribbons |
self.sinnoh_contest_ribbons)
# XXX: ribbons setter
@property
def nickname(self):
return self.structure.nickname
@nickname.setter
def nickname(self, value):
self.structure.nickname = value
self.structure.is_nicknamed = True
@nickname.deleter
def nickname(self, value):
self.structure.nickname = ''
self.structure.is_nicknamed = False
### Utility methods
shuffle_orders = list( permutations(range(4)) )
@classmethod
def shuffle_chunks(cls, words, reverse=False):
"""The main 128 encrypted bytes (or 64 words) in a save block are split
into four chunks and shuffled around in some order, based on
personality. The actual order of shuffling is a permutation of four
items in order, indexed by the shuffle index. That is, 0 yields 0123,
1 yields 0132, 2 yields 0213, etc.
Given a list of words (the first of which should be the pid), this
function returns the words in shuffled order. Pass reverse=True to
unshuffle instead.
"""
pid = words[0]
shuffle_index = (pid >> 0xD & 0x1F) % 24
shuffle_order = cls.shuffle_orders[shuffle_index]
if reverse:
# Decoding requires going the other way; invert the order
shuffle_order = [shuffle_order.index(i) for i in range(4)]
shuffled = words[:3] # skip the unencrypted stuff
for chunk in shuffle_order:
shuffled += words[ chunk * 16 + 3 : chunk * 16 + 19 ]
shuffled += words[67:] # extra bytes are also left alone
return shuffled
@classmethod
def reciprocal_crypt(cls, words):
u"""Applies the reciprocal Pokémon save file cipher to the provided
list of words.
Returns nothing; the list is changed in-place.
"""
# Apply regular Pokémon "encryption": xor everything with the output of
# the PRNG. First three items are pid/unused/checksum and are not
# encrypted.
# Main data is encrypted using the checksum as a seed
prng = pokemon_prng(words[2])
for i in range(3, 67):
words[i] ^= next(prng)
if len(words) > 67:
# Extra bytes are encrypted using the pid as a seed
prng = pokemon_prng(words[0])
for i in range(67, len(words)):
words[i] ^= next(prng)
return
def _reset(self):
"""Update self with modified pokemon_struct
Rebuilds the blob; recalculates checksum; if a session was set,
re-fetches the DB objects.
"""
self.blob = self.pokemon_struct.build(self.structure)
self.structure = self.pokemon_struct.parse(self.blob)
checksum = sum(struct.unpack('H' * 0x40, self.blob[8:0x88])) & 0xffff
self.structure.checksum = checksum
self.blob = self.blob[:6] + struct.pack('H', checksum) + self.blob[8:]
if self._session:
self.use_database_session(self._session)
class SaveFilePokemonGen4(SaveFilePokemon):
generation_id = 4
pokemon_struct = make_pokemon_struct(generation=generation_id)
def export(self):
result = super(SaveFilePokemonGen5, self).export()
if any(self.shiny_leaves):
result['shiny leaves'] = self.shiny_leaves
return result
@property
def shiny_leaves(self):
return (
self.structure.shining_leaves.leaf1,
self.structure.shining_leaves.leaf2,
self.structure.shining_leaves.leaf3,
self.structure.shining_leaves.leaf4,
self.structure.shining_leaves.leaf5,
self.structure.shining_leaves.crown,
)
@shiny_leaves.setter
def shiny_leaves(self, new_values):
(
self.structure.shining_leaves.leaf1,
self.structure.shining_leaves.leaf2,
self.structure.shining_leaves.leaf3,
self.structure.shining_leaves.leaf4,
self.structure.shining_leaves.leaf5,
self.structure.shining_leaves.crown,
) = new_values
self._reset()
class SaveFilePokemonGen5(SaveFilePokemon):
generation_id = 5
pokemon_struct = make_pokemon_struct(generation=generation_id)
def use_database_session(self, session):
super(SaveFilePokemonGen5, self).use_database_session(session)
st = self.structure
if st.nature_id:
self._nature = session.query(tables.Nature) \
.filter_by(game_index = st.nature_id).one()
def export(self):
result = super(SaveFilePokemonGen5, self).export()
result['nature'] = dict(id=self.nature.id, name=self.nature.name)
return result
# XXX: Ability setter must set hidden ability flag
@property
def nature(self):
return self._nature
@nature.setter
def nature(self, new_nature):
self.structure.nature_id = int(new_nature.game_index)
self._reset()
save_file_pokemon_classes = {
4: SaveFilePokemonGen4,
5: SaveFilePokemonGen5,
}