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Diffstat (limited to 'pokemontools/vba/battle.py')
| -rw-r--r-- | pokemontools/vba/battle.py | 521 |
1 files changed, 521 insertions, 0 deletions
diff --git a/pokemontools/vba/battle.py b/pokemontools/vba/battle.py new file mode 100644 index 0000000..39d7047 --- /dev/null +++ b/pokemontools/vba/battle.py @@ -0,0 +1,521 @@ +""" +Code that attempts to model a battle. +""" + +from pokemontools.vba.vba import crystal as emulator +import pokemontools.vba.vba as vba + +class BattleException(Exception): + """ + Something went terribly wrong in a battle. + """ + +class EmulatorController(object): + """ + Controls the emulator. I don't have a good reason for this. + """ + +class Battle(EmulatorController): + """ + Wrapper around the battle routine inside of the game. This object controls + the emulator and provides a sanitized interface for interacting with a + battle through python. + """ + + def __init__(self, emulator=None): + """ + Setup the battle. + """ + self.emulator = emulator + + def is_in_battle(self): + """ + @rtype: bool + """ + return self.emulator.is_in_battle() + + def is_input_required(self): + """ + Detects if the battle is waiting for player input. + """ + return self.is_player_turn() or self.is_mandatory_switch() or self.is_switch_prompt() or self.is_levelup_screen() or self.is_make_room_for_move_prompt() + + def is_fight_pack_run_menu(self): + """ + Attempts to detect if the current menu is fight-pack-run. This is only + for whether or not the player needs to choose what to do next. + """ + signs = ["FIGHT", "PACK", "RUN"] + screentext = self.emulator.get_text() + return all([sign in screentext for sign in signs]) + + def select_battle_menu_action(self, action, execute=True): + """ + Moves the cursor to the requested action and selects it. + + :param action: fight, pkmn, pack, run + """ + if not self.is_fight_pack_run_menu(): + raise Exception( + "This isn't the fight-pack-run menu." + ) + + action = action.lower() + + action_map = { + "fight": (1, 1), + "pkmn": (1, 2), + "pack": (2, 1), + "run": (2, 2), + } + + if action not in action_map.keys(): + raise Exception( + "Unexpected requested action {0}".format(action) + ) + + current_row = self.emulator.vba.read_memory_at(0xcfa9) + current_column = self.emulator.vba.read_memory_at(0xcfaa) + + direction = None + if current_row != action_map[action][0]: + if current_row > action_map[action][0]: + direction = "u" + elif current_row < action_map[action][0]: + direction = "d" + + self.emulator.vba.press(direction, hold=5, after=10) + + direction = None + if current_column != action_map[action][1]: + if current_column > action_map[action][1]: + direction = "l" + elif current_column < action_map[action][1]: + direction = "r" + + self.emulator.vba.press(direction, hold=5, after=10) + + # now select the action + if execute: + self.emulator.vba.press("a", hold=5, after=100) + + def select_attack(self, move_number=1, hold=5, after=10): + """ + Moves the cursor to the correct attack in the menu and presses the + button. + + :param move_number: the attack number on the FIGHT menu. Note that this + starts from 1. + :param hold: how many frames to hold each button press + :param after: how many frames to wait after each button press + """ + # TODO: detect fight menu and make sure it's detected here. + + pp_address = 0xc634 + (move_number - 1) + pp = self.emulator.vba.read_memory_at(pp_address) + + # detect zero pp because i don't want to write a way to inform the + # caller that there was no more pp. Just check the pp yourself. + if pp == 0: + raise BattleException( + "Move {num} has no more PP.".format( + num=move_number, + ) + ) + + valid_selection_states = (1, 2, 3, 4) + + selection = self.emulator.vba.read_memory_at(0xcfa9) + + while selection != move_number: + if selection not in valid_selection_states: + raise BattleException( + "The current selected attack is out of bounds: {num}".format( + num=selection, + ) + ) + + direction = None + + if selection > move_number: + direction = "d" + elif selection < move_number: + direction = "u" + else: + # probably never happens + raise BattleException( + "Not sure what to do here." + ) + + # press the arrow button + self.emulator.vba.press(direction, hold=hold, after=after) + + # let's see what the current selection is + selection = self.emulator.vba.read_memory_at(0xcfa9) + + # press to choose the attack + self.emulator.vba.press("a", hold=hold, after=after) + + def fight(self, move_number): + """ + Select FIGHT from the flight-pack-run menu and select the move + identified by move_number. + """ + # make sure the menu is detected + if not self.is_fight_pack_run_menu(): + raise BattleException( + "Wrong menu. Can't press FIGHT here." + ) + + # select FIGHT + self.select_battle_menu_action("fight") + + # select the requested attack + self.select_attack(move_number) + + def is_player_turn(self): + """ + Detects if the battle is waiting for the player to choose an attack. + """ + return self.is_fight_pack_run_menu() + + def is_trainer_switch_prompt(self): + """ + Detects if the battle is waiting for the player to choose whether or + not to switch pokemon. This is the prompt that asks yes/no for whether + to switch pokemon, like if the trainer is switching pokemon at the end + of a turn set. + """ + return self.emulator.is_trainer_switch_prompt() + + def is_wild_switch_prompt(self): + """ + Detects if the battle is waiting for the player to choose whether or + not to continue to fight the wild pokemon. + """ + return self.emulator.is_wild_switch_prompt() + + def is_switch_prompt(self): + """ + Detects both trainer and wild switch prompts (for prompting whether to + switch pokemon). This is a yes/no box and not the actual pokemon + selection menu. + """ + return self.is_trainer_switch_prompt() or self.is_wild_switch_prompt() + + def is_mandatory_switch(self): + """ + Detects if the battle is waiting for the player to choose a next + pokemon. + """ + # TODO: test when "no" fails to escape for wild battles. + # trainer battles: menu asks to select the next mon + # wild battles: yes/no box first + # The following conditions are probably sufficient: + # 1) current pokemon hp is 0 + # 2) game is polling for input + + if "CANCEL Which ?" in self.emulator.get_text(): + return True + else: + return False + + def is_levelup_screen(self): + """ + Detects the levelup stats screen. + """ + # This is implemented as reading some text on the screen instead of + # using get_text() because checking every loop is really slow. + + address = 0xc50f + values = [146, 143, 130, 139] + + for (index, value) in enumerate(values): + if self.emulator.vba.read_memory_at(address + index) != value: + return False + else: + return True + + def is_evolution_screen(self): + """ + What? MEW is evolving! + """ + address = 0xc5e4 + + values = [164, 181, 174, 171, 181, 168, 173, 166, 231] + + for (index, value) in enumerate(values): + if self.emulator.vba.read_memory_at(address + index) != value: + return False + else: + # also check "What?" + what_address = 0xc5b9 + what_values = [150, 167, 160, 179, 230] + for (index, value) in enumerate(what_values): + if self.emulator.vba.read_memory_at(what_address + index) != value: + return False + else: + return True + + def is_evolved_screen(self): + """ + Checks if the screen is the "evolved into METAPOD!" screen. Note that + this only works inside of a battle. This is because there may be other + text boxes that have the same text when outside of battle. But within a + battle, this is probably the only time the text "evolved into ... !" is + seen. + """ + if not self.is_in_battle(): + return False + + address = 0x4bb1 + values = [164, 181, 174, 171, 181, 164, 163, 127, 168, 173, 179, 174, 79] + + for (index, value) in enumerate(values): + if self.emulator.vba.read_memory_at(address + index) != value: + return False + else: + return True + + def is_make_room_for_move_prompt(self): + """ + Detects the prompt that asks whether to make room for a move. + """ + if not self.is_in_battle(): + return False + + address = 0xc5b9 + values = [172, 174, 181, 164, 127, 179, 174, 127, 172, 160, 170, 164, 127, 177, 174, 174, 172] + + for (index, value) in enumerate(values): + if self.emulator.vba.read_memory_at(address + index) != value: + return False + else: + return True + + def skip_start_text(self, max_loops=20): + """ + Skip any initial conversation until the player can select an action. + This includes skipping any text that appears on a map from an NPC as + well as text that appears prior to the first time the action selection + menu appears. + """ + if not self.is_in_battle(): + while not self.is_in_battle() and max_loops > 0: + self.emulator.text_wait() + max_loops -= 1 + + if max_loops <= 0: + raise Exception("Couldn't start the battle.") + else: + self.emulator.text_wait() + + def skip_end_text(self, loops=20): + """ + Skip through any text that appears after the final attack. + """ + if not self.is_in_battle(): + # TODO: keep talking until the character can move? A battle can be + # triggered inside of a script, and after the battle is ver the + # player may not be able to move until the script is done. The + # script might only finish after other player input is given, so + # using "text_wait() until the player can move" is a bad idea here. + self.emulator.text_wait() + else: + while self.is_in_battle() and loops > 0: + self.emulator.text_wait() + loops -= 1 + + if loops <= 0: + raise Exception("Couldn't get out of the battle.") + + def skip_until_input_required(self): + """ + Waits until the battle needs player input. + """ + # callback causes text_wait to exit when the callback returns True + def is_in_battle_checker(): + result = (self.emulator.vba.read_memory_at(0xd22d) == 0) and (self.emulator.vba.read_memory_at(0xc734) != 0) + + # but also, jump out if it's the stats screen + result = result or self.is_levelup_screen() + + # jump out if it's the "make room for a new move" screen + result = result or self.is_make_room_for_move_prompt() + + # stay in text_wait if it's the evolution screen + result = result and not self.is_evolution_screen() + + return result + + while not self.is_input_required() and self.is_in_battle(): + self.emulator.text_wait(callback=is_in_battle_checker) + + # let the text draw so that the state is more obvious + self.emulator.vba.step(count=10) + + def run(self): + """ + Step through the entire battle. + """ + # Advance to the battle from either of these states: + # 1) the player is talking with an npc + # 2) the battle has already started but there's initial text + # xyz wants to battle, a wild foobar appeared + self.skip_start_text() + + # skip a few hundred frames + self.emulator.vba.step(count=100) + + wild = (self.emulator.vba.read_memory_at(0xd22d) == 1) + + while self.is_in_battle(): + self.skip_until_input_required() + + if not self.is_in_battle(): + continue + + if self.is_player_turn(): + # battle hook provides input to handle this situation + self.handle_turn() + elif self.is_trainer_switch_prompt(): + self.handle_trainer_switch_prompt() + elif self.is_wild_switch_prompt(): + self.handle_wild_switch_prompt() + elif self.is_mandatory_switch(): + # battle hook provides input to handle this situation too + self.handle_mandatory_switch() + elif self.is_levelup_screen(): + self.emulator.vba.press("a", hold=5, after=30) + elif self.is_evolved_screen(): + self.emulator.vba.step(count=30) + elif self.is_make_room_for_move_prompt(): + self.handle_make_room_for_move() + else: + raise BattleException("unknown state, aborting") + + # "how did i lose? wah" + # TODO: this doesn't happen for wild battles + if not wild: + self.skip_end_text() + + # TODO: return should indicate win/loss (blackout) + + def handle_mandatory_switch(self): + """ + Something fainted, pick the next mon. + """ + raise NotImplementedError + + def handle_trainer_switch_prompt(self): + """ + The trainer is switching pokemon. The game asks yes/no for whether or + not the player would like to switch. + """ + raise NotImplementedError + + def handle_wild_switch_prompt(self): + """ + The wild pokemon defeated the party pokemon. This is the yes/no box for + whether to switch pokemon or not. + """ + raise NotImplementedError + + def handle_turn(self): + """ + Take actions inside of a battle based on the game state. + """ + raise NotImplementedError + +class BattleStrategy(Battle): + """ + This class shows the relevant methods to make a battle handler. + """ + + def handle_mandatory_switch(self): + """ + Something fainted, pick the next mon. + """ + raise NotImplementedError + + def handle_trainer_switch_prompt(self): + """ + The trainer is switching pokemon. The game asks yes/no for whether or + not the player would like to switch. + """ + raise NotImplementedError + + def handle_wild_switch_prompt(self): + """ + The wild pokemon defeated the party pokemon. This is the yes/no box for + whether to switch pokemon or not. + """ + raise NotImplementedError + + def handle_turn(self): + """ + Take actions inside of a battle based on the game state. + """ + raise NotImplementedError + + def handle_make_room_for_move(self): + """ + Choose yes/no then handle learning the move. + """ + raise NotImplementedError + +class SpamBattleStrategy(BattleStrategy): + """ + A really simple battle strategy that always picks the first move of the + first pokemon to attack the enemy. + """ + + def handle_turn(self): + """ + Always picks the first move of the current pokemon. + """ + self.fight(1) + + def handle_trainer_switch_prompt(self): + """ + The trainer is switching pokemon. The game asks yes/no for whether or + not the player would like to switch. + """ + # decline + self.emulator.vba.press(["b"], hold=5, after=10) + + def handle_wild_switch_prompt(self): + """ + The wild pokemon defeated the party pokemon. This is the yes/no box for + whether to switch pokemon or not. + """ + # why not just make a battle strategy that doesn't lose? + # TODO: Note that the longer "after" value is required here. + self.emulator.vba.press("a", hold=5, after=30) + + self.handle_mandatory_switch() + + def handle_mandatory_switch(self): + """ + Something fainted, pick the next mon. + """ + + # TODO: make a better selector for which pokemon. + + # now scroll down + self.emulator.vba.press("d", hold=5, after=10) + + # select this mon + self.emulator.vba.press("a", hold=5, after=30) + + def handle_make_room_for_move(self): + """ + Choose yes/no then handle learning the move. + """ + # make room? no + self.emulator.vba.press("b", hold=5, after=100) + + # stop learning? yes + self.emulator.vba.press("a", hold=5, after=20) + + self.emulator.text_wait() |