ItemPool.py

from __future__ import annotations
import random
from collections import Counter
from collections.abc import Sequence
from decimal import Decimal, ROUND_UP
from typing import TYPE_CHECKING, Optional

from Item import Item, ItemInfo, ItemFactory
from Location import DisableType

if TYPE_CHECKING:
    from Plandomizer import ItemPoolRecord
    from World import World


plentiful_items: list[str] = ([
    'Biggoron Sword',
    'Boomerang',
    'Lens of Truth',
    'Megaton Hammer',
    'Iron Boots',
    'Goron Tunic',
    'Zora Tunic',
    'Hover Boots',
    'Mirror Shield',
    'Fire Arrows',
    'Light Arrows',
    'Dins Fire',
    'Progressive Hookshot',
    'Progressive Strength Upgrade',
    'Progressive Scale',
    'Progressive Wallet',
    'Magic Meter',
    'Deku Stick Capacity',
    'Deku Nut Capacity',
    'Bow',
    'Slingshot',
    'Bomb Bag',
    'Double Defense'] +
    ['Heart Container'] * 8
)

# Ludicrous replaces all health upgrades with heart containers
# as done in plentiful. The item list is used separately to
# dynamically replace all junk with even levels of each item.
ludicrous_health: list[str] = ['Heart Container'] * 8

# List of items that can be multiplied in ludicrous mode.
# Used to filter the pre-plando pool for candidates instead
# of appending directly, making this list settings-independent.
# Excludes Gold Skulltula Tokens, Triforce Pieces, and health
# upgrades as they are directly tied to win conditions and
# already have a large count relative to available locations
# in the game.
#
# Base items will always be candidates to replace junk items,
# even if the player starts with all "normal" copies of an item.
ludicrous_items_base: list[str] = [
    'Light Arrows',
    'Megaton Hammer',
    'Progressive Hookshot',
    'Progressive Strength Upgrade',
    'Dins Fire',
    'Hover Boots',
    'Mirror Shield',
    'Boomerang',
    'Iron Boots',
    'Fire Arrows',
    'Progressive Scale',
    'Progressive Wallet',
    'Magic Meter',
    'Bow',
    'Slingshot',
    'Bomb Bag',
    'Bombchus (10)',
    'Lens of Truth',
    'Goron Tunic',
    'Zora Tunic',
    'Biggoron Sword',
    'Double Defense',
    'Farores Wind',
    'Nayrus Love',
    'Stone of Agony',
    'Deku Stick Capacity',
    'Deku Nut Capacity'
]

ludicrous_items_extended: list[str] = [
    'Zeldas Lullaby',
    'Eponas Song',
    'Suns Song',
    'Sarias Song',
    'Song of Time',
    'Song of Storms',
    'Minuet of Forest',
    'Prelude of Light',
    'Bolero of Fire',
    'Serenade of Water',
    'Nocturne of Shadow',
    'Requiem of Spirit',
    'Ocarina',
    'Kokiri Sword',
    'Boss Key (Ganons Castle)',
    'Boss Key (Forest Temple)',
    'Boss Key (Fire Temple)',
    'Boss Key (Water Temple)',
    'Boss Key (Shadow Temple)',
    'Boss Key (Spirit Temple)',
    'Gerudo Membership Card',
    'Small Key (Treasure Chest Game)',
    'Small Key (Thieves Hideout)',
    'Small Key (Shadow Temple)',
    'Small Key (Ganons Castle)',
    'Small Key (Forest Temple)',
    'Small Key (Spirit Temple)',
    'Small Key (Fire Temple)',
    'Small Key (Water Temple)',
    'Small Key (Bottom of the Well)',
    'Small Key (Gerudo Training Ground)',
    'Small Key Ring (Treasure Chest Game)',
    'Small Key Ring (Thieves Hideout)',
    'Small Key Ring (Shadow Temple)',
    'Small Key Ring (Ganons Castle)',
    'Small Key Ring (Forest Temple)',
    'Small Key Ring (Spirit Temple)',
    'Small Key Ring (Fire Temple)',
    'Small Key Ring (Water Temple)',
    'Small Key Ring (Bottom of the Well)',
    'Small Key Ring (Gerudo Training Ground)',
    'Magic Bean Pack',
    'Ice Arrows',
    'Blue Fire Arrows',
    'Weird Egg',
    'Chicken',
    'Zeldas Letter',
    'Keaton Mask',
    'Skull Mask',
    'Spooky Mask',
    'Bunny Hood',
    'Mask of Truth',
    'Pocket Egg',
    'Pocket Cucco',
    'Cojiro',
    'Odd Mushroom',
    'Odd Potion',
    'Poachers Saw',
    'Broken Sword',
    'Prescription',
    'Eyeball Frog',
    'Eyedrops',
    'Claim Check'
    'Silver Rupee (Dodongos Cavern Staircase)',
    'Silver Rupee (Ice Cavern Spinning Scythe)',
    'Silver Rupee (Ice Cavern Push Block)',
    'Silver Rupee (Bottom of the Well Basement)',
    'Silver Rupee (Shadow Temple Scythe Shortcut)',
    'Silver Rupee (Shadow Temple Invisible Blades)',
    'Silver Rupee (Shadow Temple Huge Pit)',
    'Silver Rupee (Shadow Temple Invisible Spikes)',
    'Silver Rupee (Gerudo Training Ground Slopes)',
    'Silver Rupee (Gerudo Training Ground Lava)',
    'Silver Rupee (Gerudo Training Ground Water)',
    'Silver Rupee (Spirit Temple Child Early Torches)',
    'Silver Rupee (Spirit Temple Adult Boulders)',
    'Silver Rupee (Spirit Temple Lobby and Lower Adult)',
    'Silver Rupee (Spirit Temple Sun Block)',
    'Silver Rupee (Spirit Temple Adult Climb)',
    'Silver Rupee (Ganons Castle Spirit Trial)',
    'Silver Rupee (Ganons Castle Light Trial)',
    'Silver Rupee (Ganons Castle Fire Trial)',
    'Silver Rupee (Ganons Castle Shadow Trial)',
    'Silver Rupee (Ganons Castle Water Trial)',
    'Silver Rupee (Ganons Castle Forest Trial)',
    'Silver Rupee Pouch (Dodongos Cavern Staircase)',
    'Silver Rupee Pouch (Ice Cavern Spinning Scythe)',
    'Silver Rupee Pouch (Ice Cavern Push Block)',
    'Silver Rupee Pouch (Bottom of the Well Basement)',
    'Silver Rupee Pouch (Shadow Temple Scythe Shortcut)',
    'Silver Rupee Pouch (Shadow Temple Invisible Blades)',
    'Silver Rupee Pouch (Shadow Temple Huge Pit)',
    'Silver Rupee Pouch (Shadow Temple Invisible Spikes)',
    'Silver Rupee Pouch (Gerudo Training Ground Slopes)',
    'Silver Rupee Pouch (Gerudo Training Ground Lava)',
    'Silver Rupee Pouch (Gerudo Training Ground Water)',
    'Silver Rupee Pouch (Spirit Temple Child Early Torches)',
    'Silver Rupee Pouch (Spirit Temple Adult Boulders)',
    'Silver Rupee Pouch (Spirit Temple Lobby and Lower Adult)',
    'Silver Rupee Pouch (Spirit Temple Sun Block)',
    'Silver Rupee Pouch (Spirit Temple Adult Climb)',
    'Silver Rupee Pouch (Ganons Castle Spirit Trial)',
    'Silver Rupee Pouch (Ganons Castle Light Trial)',
    'Silver Rupee Pouch (Ganons Castle Fire Trial)',
    'Silver Rupee Pouch (Ganons Castle Shadow Trial)',
    'Silver Rupee Pouch (Ganons Castle Water Trial)',
    'Silver Rupee Pouch (Ganons Castle Forest Trial)',
    'Ocarina A Button',
    'Ocarina C up Button',
    'Ocarina C left Button',
    'Ocarina C down Button',
    'Ocarina C right Button',
]

ludicrous_exclusions: tuple[str, ...] = (
    'Triforce Piece',
    'Gold Skulltula Token',
    'Rutos Letter',
    'Heart Container',
    'Piece of Heart',
    'Piece of Heart (Treasure Chest Game)',
)

item_difficulty_max: dict[str, dict[str, int]] = {
    'ludicrous': {
        'Piece of Heart': 3,
    },
    'plentiful': {
        'Piece of Heart': 3,
    },
    'balanced': {},
    'scarce': {
        'Bombchus (5)': 1,
        'Bombchus (10)': 2,
        'Bombchus (20)': 0,
        'Magic Meter': 1,
        'Double Defense': 0,
        'Deku Stick Capacity': 1,
        'Deku Nut Capacity': 1,
        'Bow': 2,
        'Slingshot': 2,
        'Bomb Bag': 2,
        'Heart Container': 0,
    },
    'minimal': {
        'Bombchus (5)': 1,
        'Bombchus (10)': 0,
        'Bombchus (20)': 0,
        'Magic Meter': 1,
        'Nayrus Love': 1,
        'Double Defense': 0,
        'Deku Stick Capacity': 0,
        'Deku Nut Capacity': 0,
        'Bow': 1,
        'Slingshot': 1,
        'Bomb Bag': 1,
        'Heart Container': 0,
        'Piece of Heart': 0,
    },
}

shopsanity_rupees: list[str] = (
    ['Rupees (20)'] * 5 +
    ['Rupees (50)'] * 3 +
    ['Rupees (200)'] * 2
)

min_shop_items: list[str] = (
    ['Buy Deku Shield'] +
    ['Buy Hylian Shield'] +
    ['Buy Goron Tunic'] +
    ['Buy Zora Tunic'] +
    ['Buy Deku Nut (5)'] * 2 + ['Buy Deku Nut (10)'] +
    ['Buy Deku Stick (1)'] * 2 +
    ['Buy Deku Seeds (30)'] +
    ['Buy Arrows (10)'] * 2 + ['Buy Arrows (30)'] + ['Buy Arrows (50)'] +
    ['Buy Bombchu (5)'] + ['Buy Bombchu (10)'] * 2 + ['Buy Bombchu (20)'] +
    ['Buy Bombs (5) for 25 Rupees'] + ['Buy Bombs (5) for 35 Rupees'] + ['Buy Bombs (10)'] + ['Buy Bombs (20)'] +
    ['Buy Green Potion'] +
    ['Buy Red Potion for 30 Rupees'] +
    ['Buy Blue Fire'] +
    ["Buy Fairy's Spirit"] +
    ['Buy Bottle Bug'] +
    ['Buy Fish']
)

deku_scrubs_items: dict[str, str | list[tuple[str, int]]] = {
    'Buy Deku Shield':     'Deku Shield',
    'Buy Deku Nut (5)':    'Deku Nuts (5)',
    'Buy Deku Stick (1)':  'Deku Stick (1)',
    'Buy Bombs (5) for 35 Rupees':  'Bombs (5)',
    'Buy Red Potion for 30 Rupees': 'Recovery Heart',
    'Buy Green Potion':    'Rupees (5)',
    'Buy Arrows (30)':     [('Arrows (30)', 3), ('Deku Seeds (30)', 1)],
    'Buy Deku Seeds (30)': [('Arrows (30)', 3), ('Deku Seeds (30)', 1)],
}

trade_items: tuple[str, ...] = (
    "Pocket Egg",
    "Pocket Cucco",
    "Cojiro",
    "Odd Mushroom",
    "Odd Potion",
    "Poachers Saw",
    "Broken Sword",
    "Prescription",
    "Eyeball Frog",
    "Eyedrops",
    "Claim Check",
)

child_trade_items: tuple[str, ...] = (
    "Weird Egg",
    "Chicken",
    "Zeldas Letter",
    "Keaton Mask",
    "Skull Mask",
    "Spooky Mask",
    "Bunny Hood",
    "Goron Mask",
    "Zora Mask",
    "Gerudo Mask",
    "Mask of Truth",
)

normal_bottles: list[str] = [bottle for bottle in sorted(ItemInfo.bottles) if bottle not in ('Deliver Letter', 'Sell Big Poe')] + ['Bottle with Big Poe']
song_list: list[str] = [item.name for item in sorted([i for n, i in ItemInfo.items.items() if i.type == 'Song'], key=lambda x: x.index if x.index is not None else 0)]
junk_pool_base: list[tuple[str, int]] = [(item, weight) for (item, weight) in sorted(ItemInfo.junk_weight.items()) if weight > 0]
remove_junk_items: list[str] = [item for (item, weight) in sorted(ItemInfo.junk_weight.items()) if weight >= 0]

remove_junk_ludicrous_items: list[str] = [
    'Ice Arrows',
    'Deku Nut Capacity',
    'Deku Stick Capacity',
    'Double Defense',
    'Biggoron Sword'
]

# a useless placeholder item placed at some skipped and inaccessible locations
# (e.g. HC Malon Egg with Skip Child Zelda, or the carpenters with Open Gerudo Fortress)
IGNORE_LOCATION: str = 'Recovery Heart'

pending_junk_pool: list[str] = []
junk_pool: list[tuple[str, int]] = []

exclude_from_major: list[str] = [
    'Deliver Letter',
    'Sell Big Poe',
    'Magic Bean',
    'Buy Magic Bean',
    'Zeldas Letter',
    'Bombchus (5)',
    'Bombchus (10)',
    'Bombchus (20)',
    'Odd Potion',
    'Triforce Piece',
    'Heart Container',
    'Piece of Heart',
    'Piece of Heart (Treasure Chest Game)',
]

item_groups: dict[str, Sequence[str]] = {
    'Junk': remove_junk_items,
    'JunkSong': ('Prelude of Light', 'Serenade of Water'),
    'AdultTrade': trade_items,
    'ChildTrade': child_trade_items,
    'Bottle': normal_bottles,
    'Spell': ('Dins Fire', 'Farores Wind', 'Nayrus Love'),
    'Shield': ('Deku Shield', 'Hylian Shield'),
    'Song': song_list,
    'NonWarpSong': song_list[6:],
    'WarpSong': song_list[0:6],
    'HealthUpgrade': ('Heart Container', 'Piece of Heart', 'Piece of Heart (Treasure Chest Game)'),
    'ProgressItem': sorted([name for name, item in ItemInfo.items.items() if item.type == 'Item' and item.advancement]),
    'MajorItem': sorted([name for name, item in ItemInfo.items.items() if item.type in ('Item', 'Song') and item.advancement and name not in exclude_from_major]),
    'DungeonReward': [item.name for item in sorted([i for n, i in ItemInfo.items.items() if i.type == 'DungeonReward'], key=lambda x: x.special['item_id'])],
    'Map': sorted([name for name, item in ItemInfo.items.items() if item.type == 'Map']),
    'Compass': sorted([name for name, item in ItemInfo.items.items() if item.type == 'Compass']),
    'BossKey': sorted([name for name, item in ItemInfo.items.items() if item.type == 'BossKey']),
    'SmallKey': sorted([name for name, item in ItemInfo.items.items() if item.type == 'SmallKey']),

    'ForestFireWater': ('Forest Medallion', 'Fire Medallion', 'Water Medallion'),
    'FireWater': ('Fire Medallion', 'Water Medallion'),
}


def get_junk_item(count: int = 1, pool: Optional[list[str]] = None, plando_pool: Optional[dict[str, ItemPoolRecord]] = None) -> list[str]:
    if count < 1:
        raise ValueError("get_junk_item argument 'count' must be greater than 0.")

    return_pool = []
    if pending_junk_pool:
        pending_count = min(len(pending_junk_pool), count)
        return_pool = [pending_junk_pool.pop() for _ in range(pending_count)]
        count -= pending_count

    if pool and plando_pool:
        jw_dict = {junk: weight for (junk, weight) in junk_pool
                   if junk not in plando_pool or pool.count(junk) < plando_pool[junk].count}
        if not jw_dict:
            raise RuntimeError("Not enough junk is available in the item pool to replace removed items.")
    else:
        jw_dict = {junk: weight for (junk, weight) in junk_pool}
    return_pool.extend(random.choices(list(jw_dict.keys()), weights=list(jw_dict.values()), k=count))

    return return_pool


def replace_max_item(items: list[str], item: str, max_count: int) -> None:
    count = 0
    for i, val in enumerate(items):
        if val == item:
            if count >= max_count:
                items[i] = get_junk_item()[0]
            count += 1


def generate_itempool(world: World) -> None:
    junk_pool[:] = list(junk_pool_base)
    if world.settings.junk_ice_traps == 'on':
        junk_pool.append(('Ice Trap', 10))
    elif world.settings.junk_ice_traps in ('mayhem', 'onslaught'):
        junk_pool[:] = [('Ice Trap', 1)]

    # set up item pool
    (pool, placed_items) = get_pool_core(world)
    placed_items_count = {}
    world.itempool = ItemFactory(pool, world)
    world.initialize_items(world.itempool + list(placed_items.values()))
    placed_locations = list(filter(lambda loc: loc.name in placed_items, world.get_locations()))
    for location in placed_locations:
        item = placed_items[location.name]
        placed_items_count[item.name] = placed_items_count.get(item.name, 0) + 1
        world.push_item(location, item)
        world.get_location(location).locked = True

    world.distribution.set_complete_itempool(world.itempool)

    # make sure that there are enough gold skulltulas for bridge/ganon boss key/lacs
    world.available_tokens = (placed_items_count.get("Gold Skulltula Token", 0)
                              + pool.count("Gold Skulltula Token")
                              + world.distribution.get_starting_item("Gold Skulltula Token"))
    if world.max_progressions["Gold Skulltula Token"] > world.available_tokens:
        raise ValueError(f"Not enough available Gold Skulltula Tokens to meet requirements. Available: {world.available_tokens}, Required: {world.max_progressions['Gold Skulltula Token']}.")


def get_pool_core(world: World) -> tuple[list[str], dict[str, Item]]:
    pool = []
    placed_items = {}
    remain_shop_items = []
    ruto_bottles = 1
    blue_potions = 1

    if world.settings.zora_fountain == 'open':
        ruto_bottles = 0

    if world.settings.shopsanity not in ('off', '0'):
        pending_junk_pool.append('Progressive Wallet')

    if world.settings.item_pool_value == 'plentiful':
        pending_junk_pool.extend(plentiful_items)
        if world.settings.shuffle_child_trade:
            pending_junk_pool.extend(world.settings.shuffle_child_trade)
            # Weird Egg is always chosen if both Egg and Chicken are selected to be shuffled.
            # Make the duplicate item consistent with that.
            if 'Weird Egg' in world.settings.shuffle_child_trade and 'Chicken' in world.settings.shuffle_child_trade:
                pending_junk_pool.remove('Chicken')
            if world.skip_child_zelda:
                for item in ('Weird Egg', 'Chicken', 'Zeldas Letter'):
                    if item in pending_junk_pool:
                        pending_junk_pool.remove(item)
        if world.settings.adult_trade_shuffle:
            pending_junk_pool.extend(world.settings.adult_trade_start)
            # Pocket Egg is always chosen if both Egg and Pocket Cucco are selected to be shuffled.
            # Make the duplicate item consistent with that.
            if 'Pocket Egg' in world.settings.adult_trade_start and 'Pocket Cucco' in world.settings.adult_trade_start:
                pending_junk_pool.remove('Pocket Cucco')
        else:
            # With adult trade shuffle off, add a random extra adult trade item
            item = random.choice(world.settings.adult_trade_start)
            pending_junk_pool.append(item)
        if world.settings.zora_fountain != 'open':
            ruto_bottles += 1
        if world.settings.shuffle_kokiri_sword:
            pending_junk_pool.append('Kokiri Sword')
        if world.settings.shuffle_ocarinas:
            pending_junk_pool.append('Ocarina')
        if world.settings.shuffle_beans and world.distribution.get_starting_item('Magic Bean') < 10:
            pending_junk_pool.append('Magic Bean Pack')
        if (world.settings.gerudo_fortress != "open"
                and world.settings.shuffle_hideoutkeys in ('any_dungeon', 'overworld', 'keysanity', 'regional')):
            if 'Thieves Hideout' in world.settings.key_rings and world.settings.gerudo_fortress != "fast":
                pending_junk_pool.append('Small Key Ring (Thieves Hideout)')
            else:
                pending_junk_pool.append('Small Key (Thieves Hideout)')
        if world.settings.shuffle_tcgkeys in ('any_dungeon', 'overworld', 'keysanity', 'regional'):
            if 'Treasure Chest Game' in world.settings.key_rings:
                pending_junk_pool.append('Small Key Ring (Treasure Chest Game)')
            else:
                pending_junk_pool.append('Small Key (Treasure Chest Game)')
        if world.settings.shuffle_gerudo_card:
            pending_junk_pool.append('Gerudo Membership Card')
        if world.settings.shuffle_smallkeys in ('any_dungeon', 'overworld', 'keysanity', 'regional'):
            for dungeon in ('Forest Temple', 'Fire Temple', 'Water Temple', 'Shadow Temple', 'Spirit Temple',
                            'Bottom of the Well', 'Gerudo Training Ground', 'Ganons Castle'):
                if dungeon in world.settings.key_rings:
                    pending_junk_pool.append(f"Small Key Ring ({dungeon})")
                else:
                    pending_junk_pool.append(f"Small Key ({dungeon})")
        if world.settings.shuffle_bosskeys in ('any_dungeon', 'overworld', 'keysanity', 'regional'):
            for dungeon in ('Forest Temple', 'Fire Temple', 'Water Temple', 'Shadow Temple', 'Spirit Temple'):
                if not world.settings.keyring_give_bk or dungeon not in world.settings.key_rings or world.settings.shuffle_smallkeys == 'vanilla':
                    pending_junk_pool.append(f"Boss Key ({dungeon})")
        if world.settings.shuffle_ganon_bosskey in ('any_dungeon', 'overworld', 'keysanity', 'regional'):
            pending_junk_pool.append('Boss Key (Ganons Castle)')
        if world.settings.shuffle_silver_rupees in ('any_dungeon', 'overworld', 'anywhere', 'regional'):
            for puzzle in world.silver_rupee_puzzles():
                if puzzle in world.settings.silver_rupee_pouches:
                    pending_junk_pool.append(f"Silver Rupee Pouch ({puzzle})")
                else:
                    pending_junk_pool.append(f"Silver Rupee ({puzzle})")
        if world.settings.shuffle_song_items == 'any':
            pending_junk_pool.extend(song_list)
        if world.settings.shuffle_individual_ocarina_notes:
            pending_junk_pool.extend(['Ocarina A Button', 'Ocarina C up Button', 'Ocarina C left Button', 'Ocarina C down Button', 'Ocarina C right Button'])

    if world.settings.item_pool_value == 'ludicrous':
        pending_junk_pool.extend(ludicrous_health)

    if world.settings.triforce_hunt:
        pending_junk_pool.extend(['Triforce Piece'] * world.settings.triforce_count_per_world)
    if world.settings.shuffle_individual_ocarina_notes:
        pending_junk_pool.append('Ocarina A Button')
        pending_junk_pool.append('Ocarina C up Button')
        pending_junk_pool.append('Ocarina C left Button')
        pending_junk_pool.append('Ocarina C down Button')
        pending_junk_pool.append('Ocarina C right Button')

    # Use the vanilla items in the world's locations when appropriate.
    vanilla_items_processed = Counter()
    for location in world.get_locations():
        if location.vanilla_item is None:
            continue

        item = location.vanilla_item
        shuffle_item = None  # None for don't handle, False for place item, True for add to pool.

        # Always Placed Items
        if (location.vanilla_item in ('Triforce', 'Scarecrow Song',
                                      'Deliver Letter', 'Time Travel', 'Bombchu Drop')
                or location.type == 'Drop'):
            shuffle_item = False

        # Gold Skulltula Tokens
        elif location.vanilla_item == 'Gold Skulltula Token':
            shuffle_item = (world.settings.tokensanity == 'all'
                            or (world.settings.tokensanity == 'dungeons' and location.dungeon)
                            or (world.settings.tokensanity == 'overworld' and not location.dungeon))

        # Shops
        elif location.type == "Shop":
            if world.settings.shopsanity == 'off':
                shuffle_item = False
            else:
                remain_shop_items.append(item)

        # Business Scrubs
        elif location.type in ("Scrub", "GrottoScrub"):
            if location.vanilla_item in ('Piece of Heart', 'Deku Stick Capacity', 'Deku Nut Capacity'):
                shuffle_item = True
            elif world.settings.shuffle_scrubs == 'off':
                shuffle_item = False
            else:
                item = deku_scrubs_items[location.vanilla_item]
                if isinstance(item, list):
                    item = random.choices([i[0] for i in item], weights=[i[1] for i in item], k=1)[0]
                shuffle_item = True

        # Kokiri Sword
        elif location.vanilla_item == 'Kokiri Sword':
            shuffle_item = world.settings.shuffle_kokiri_sword

        # Ice Arrows/Blue Fire Arrows
        elif location.vanilla_item == 'Ice Arrows':
            if world.settings.blue_fire_arrows:
                item = 'Blue Fire Arrows'
            shuffle_item = True

        # Ocarinas
        elif location.vanilla_item == 'Ocarina':
            shuffle_item = world.settings.shuffle_ocarinas

        # Giant's Knife
        elif location.vanilla_item == 'Giants Knife':
            shuffle_item = world.settings.shuffle_expensive_merchants

        # Bombchu Bowling 3rd and 4th prizes (must be checked before Bombchu vanilla items!)
        elif location.name in ('Market Bombchu Bowling Bombchus', 'Market Bombchu Bowling Bomb'):
            shuffle_item = False

        # Bombchus
        elif location.vanilla_item in ('Bombchus', 'Bombchus (5)', 'Bombchus (10)', 'Bombchus (20)'):
            shuffle_item = location.name != 'Wasteland Bombchu Salesman' or world.settings.shuffle_expensive_merchants

        # Blue Potion from Granny's Potion Shop
        elif location.vanilla_item == 'Blue Potion':
            if world.settings.shuffle_expensive_merchants:
                shuffle_item = True
                # Don't shuffle the shop item. One of the bottles is forced to be a blue potion
                # to simulate shuffling.
                item = get_junk_item()[0]
            else:
                shuffle_item = False

        # Cows
        elif location.vanilla_item == 'Milk':
            if world.settings.shuffle_cows:
                item = get_junk_item()[0]
            shuffle_item = world.settings.shuffle_cows

        # Gerudo Card
        elif location.vanilla_item == 'Gerudo Membership Card':
            shuffle_item = world.settings.shuffle_gerudo_card and world.settings.gerudo_fortress != 'open'
            if world.settings.gerudo_fortress == 'open':
                if world.settings.shuffle_gerudo_card:
                    pending_junk_pool.append(item)
                    item = IGNORE_LOCATION
                else:
                    world.state.collect(ItemFactory(item))

        # Bottles
        elif location.vanilla_item in ('Bottle', 'Bottle with Milk', 'Rutos Letter'):
            if ruto_bottles:
                item = 'Rutos Letter'
                ruto_bottles -= 1
            # Add one blue potion to world if Granny's Potion Shop is shuffled
            elif world.settings.shuffle_expensive_merchants and blue_potions:
                item = "Bottle with Blue Potion"
                blue_potions -= 1
            else:
                item = random.choice(normal_bottles)
            shuffle_item = True

        # Magic Beans
        elif location.vanilla_item == 'Buy Magic Bean':
            if world.settings.shuffle_beans:
                item = 'Magic Bean Pack' if world.distribution.get_starting_item('Magic Bean') < 10 else get_junk_item()[0]
            shuffle_item = world.settings.shuffle_beans

        # Frogs Purple Rupees
        elif location.scene == 0x54 and location.vanilla_item == 'Rupees (50)':
            shuffle_item = world.settings.shuffle_frog_song_rupees

        # Hyrule Loach Reward
        elif location.scene == 0x49 and location.vanilla_item == 'Rupees (50)':
            shuffle_item = world.settings.shuffle_loach_reward != 'off'

        # Adult Trade Quest Items
        elif location.vanilla_item in trade_items:
            if not world.settings.adult_trade_shuffle:
                if location.vanilla_item == 'Pocket Egg' and world.settings.adult_trade_start:
                    item = world.selected_adult_trade_item
                    shuffle_item = True
                else:
                    shuffle_item = False
            elif location.vanilla_item in world.settings.adult_trade_start:
                shuffle_item = True
            else:
                # Upgrade Pocket Egg to Pocket Cucco if the Cucco is shuffled but not the Egg.
                # If both are selected to be shuffled, only the Egg gets shuffled.
                if location.vanilla_item == 'Pocket Egg' and 'Pocket Cucco' in world.settings.adult_trade_start:
                    item = 'Pocket Cucco'
                    shuffle_item = True
                else:
                    shuffle_item = False

        # Child Trade Quest Items
        elif location.vanilla_item in child_trade_items:
            if location.vanilla_item == 'Weird Egg' and world.skip_child_zelda:
                world.state.collect(ItemFactory(location.vanilla_item, world))
                item = IGNORE_LOCATION
                shuffle_item = False
            elif not world.settings.shuffle_child_trade:
                shuffle_item = False
            elif location.vanilla_item in world.settings.shuffle_child_trade:
                shuffle_item = True
            else:
                # Upgrade Weird Egg to Chicken if the Chicken is shuffled but not the Egg.
                # If both are selected to be shuffled, only the Egg gets shuffled.
                if location.vanilla_item == 'Weird Egg' and 'Chicken' in world.settings.shuffle_child_trade:
                    item = 'Chicken'
                    shuffle_item = True
                else:
                    shuffle_item = False

        # Thieves' Hideout
        elif location.vanilla_item == 'Small Key (Thieves Hideout)':
            shuffle_item = world.settings.shuffle_hideoutkeys != 'vanilla'
            if (world.settings.gerudo_fortress == 'open'
                    or world.settings.gerudo_fortress == 'fast' and location.name != 'Hideout 1 Torch Jail Gerudo Key'):
                item = IGNORE_LOCATION
                shuffle_item = False
            if shuffle_item and world.settings.gerudo_fortress == 'normal' and 'Thieves Hideout' in world.settings.key_rings:
                item = get_junk_item()[0] if vanilla_items_processed[location.vanilla_item] else 'Small Key Ring (Thieves Hideout)'

        # Treasure Chest Game Key Shuffle
        elif location.vanilla_item != 'Piece of Heart (Treasure Chest Game)' and location.scene == 0x10:
            if world.settings.shuffle_tcgkeys in ('regional', 'overworld', 'any_dungeon', 'keysanity'):
                if 'Treasure Chest Game' in world.settings.key_rings and location.vanilla_item == 'Small Key (Treasure Chest Game)':
                    item = get_junk_item()[0] if location.name != 'Market Treasure Chest Game Salesman' else 'Small Key Ring (Treasure Chest Game)'
                shuffle_item = True
            elif world.settings.shuffle_tcgkeys == 'remove':
                if location.vanilla_item == 'Small Key (Treasure Chest Game)':
                    world.state.collect(ItemFactory(item))
                    item = get_junk_item()[0]
                shuffle_item = True
            else:
                shuffle_item = False
                location.disabled = DisableType.DISABLED

        # Freestanding Rupees and Hearts
        elif location.type in ('ActorOverride', 'Freestanding', 'RupeeTower'):
            if world.settings.shuffle_freestanding_items == 'all':
                shuffle_item = True
            elif world.settings.shuffle_freestanding_items == 'dungeons' and location.dungeon is not None:
                shuffle_item = True
            elif world.settings.shuffle_freestanding_items == 'overworld' and location.dungeon is None:
                shuffle_item = True
            else:
                shuffle_item = False
                location.disabled = DisableType.DISABLED

        # Pots
        elif location.type in ('Pot', 'FlyingPot'):
            if world.settings.shuffle_pots == 'all':
                shuffle_item = True
            elif world.settings.shuffle_pots == 'dungeons' and (location.dungeon is not None or (location.parent_region is not None and location.parent_region.is_boss_room)):
                shuffle_item = True
            elif world.settings.shuffle_pots == 'overworld' and not (location.dungeon is not None or (location.parent_region is not None and location.parent_region.is_boss_room)):
                shuffle_item = True
            else:
                shuffle_item = False
                location.disabled = DisableType.DISABLED

        # Crates
        elif location.type in ('Crate', 'SmallCrate'):
            if world.settings.shuffle_crates == 'all':
                shuffle_item = True
            elif world.settings.shuffle_crates == 'dungeons' and location.dungeon is not None:
                shuffle_item = True
            elif world.settings.shuffle_crates == 'overworld' and location.dungeon is None:
                shuffle_item = True
            else:
                shuffle_item = False
                location.disabled = DisableType.DISABLED

        # Beehives
        elif location.type == 'Beehive':
            if world.settings.shuffle_beehives:
                shuffle_item = True
            else:
                shuffle_item = False
                location.disabled = DisableType.DISABLED

        # Wonderitems
        elif location.type == 'Wonderitem':
            if world.settings.shuffle_wonderitems:
                shuffle_item = True
            else:
                shuffle_item = False
                location.disabled = DisableType.DISABLED

        # Dungeon Items
        elif location.dungeon is not None:
            dungeon = location.dungeon
            shuffle_setting = None
            dungeon_collection = None

            # Boss Key
            if location.vanilla_item == dungeon.item_name("Boss Key"):
                if (world.settings.shuffle_smallkeys != 'vanilla'
                        and dungeon.name in world.settings.key_rings and world.settings.keyring_give_bk
                        and dungeon.name in ('Forest Temple', 'Fire Temple', 'Water Temple', 'Shadow Temple', 'Spirit Temple')):
                    item = get_junk_item()[0]
                    shuffle_item = True
                else:
                    shuffle_setting = world.settings.shuffle_bosskeys if dungeon.name != 'Ganons Castle' else world.settings.shuffle_ganon_bosskey
                    dungeon_collection = dungeon.boss_key
                    if shuffle_setting == 'vanilla':
                        shuffle_item = False
            # Map or Compass
            elif location.vanilla_item in (dungeon.item_name("Map"), dungeon.item_name("Compass")):
                shuffle_setting = world.settings.shuffle_mapcompass
                dungeon_collection = dungeon.dungeon_items
                if shuffle_setting == 'vanilla':
                    shuffle_item = False
            # Small Key
            elif location.vanilla_item == dungeon.item_name("Small Key"):
                shuffle_setting = world.settings.shuffle_smallkeys
                dungeon_collection = dungeon.small_keys
                if shuffle_setting == 'vanilla':
                    shuffle_item = False
                elif dungeon.name in world.settings.key_rings and not vanilla_items_processed[location.vanilla_item]:
                    item = dungeon.item_name("Small Key Ring")
                elif dungeon.name in world.settings.key_rings:
                    item = get_junk_item()[0]
                    shuffle_item = True
            # Silver Rupee
            elif location.type == 'SilverRupee':
                shuffle_setting = world.settings.shuffle_silver_rupees
                dungeon_collection = dungeon.silver_rupees
                puzzle = location.vanilla_item[:-1].split('(')[1]
                if shuffle_setting == 'vanilla':
                    shuffle_item = False
                elif puzzle in world.settings.silver_rupee_pouches:
                    item = f'Silver Rupee Pouch ({puzzle})'
                    if vanilla_items_processed[location.vanilla_item]:
                        item = get_junk_item()[0]
                        shuffle_item = True
            # Any other item in a dungeon.
            elif location.type in ("Chest", "NPC", "Song", "Collectable", "Cutscene", "BossHeart"):
                shuffle_item = True

            # Handle dungeon item.
            if shuffle_setting is not None and dungeon_collection is not None and not shuffle_item:
                if shuffle_setting in ('remove', 'startwith'):
                    world.state.collect(ItemFactory(item, world))
                    item = get_junk_item()[0]
                    shuffle_item = True
                elif shuffle_setting in ('any_dungeon', 'overworld', 'keysanity', 'regional', 'anywhere') and not world.empty_dungeons[dungeon.name].empty:
                    shuffle_item = True
                elif shuffle_item is None:
                    dungeon_collection.append(ItemFactory(item, world))

        # The rest of the overworld items.
        elif location.type in ("Chest", "NPC", "Song", "Collectable", "Cutscene", "BossHeart"):
            shuffle_item = True

        # Now, handle the item as necessary.
        if shuffle_item:
            pool.append(item)
        elif shuffle_item is not None:
            placed_items[location.name] = ItemFactory(item, world)
        vanilla_items_processed[location.vanilla_item] += 1
    # End of Locations loop.

    if world.settings.shopsanity != 'off':
        pool.extend(min_shop_items)
        for item in min_shop_items:
            remain_shop_items.remove(item)

        shop_slots_count = len(remain_shop_items)
        shop_non_item_count = len(world.shop_prices)
        shop_item_count = shop_slots_count - shop_non_item_count

        pool.extend(random.sample(remain_shop_items, shop_item_count))
        if shop_non_item_count:
            pool.extend(get_junk_item(shop_non_item_count))

    # Extra rupees for shopsanity.
    if world.settings.shopsanity not in ('off', '0'):
        for rupee in shopsanity_rupees:
            if 'Rupees (5)' in pool:
                pool[pool.index('Rupees (5)')] = rupee
            else:
                pending_junk_pool.append(rupee)

    if world.settings.free_scarecrow:
        world.state.collect(ItemFactory('Scarecrow Song', world))

    if world.settings.no_epona_race:
        world.state.collect(ItemFactory('Epona', world, event=True))

    if world.settings.shuffle_smallkeys == 'vanilla':
        # Logic cannot handle vanilla key layout in some dungeons
        # this is because vanilla expects the dungeon major item to be
        # locked behind the keys, which is not always true in rando.
        # We can resolve this by starting with some extra keys
        if world.dungeon_mq['Spirit Temple']:
            # Yes somehow you need 3 keys. This dungeon is bonkers
            world.state.collect(ItemFactory('Small Key (Spirit Temple)', world))
            world.state.collect(ItemFactory('Small Key (Spirit Temple)', world))
            world.state.collect(ItemFactory('Small Key (Spirit Temple)', world))
        if 'Shadow Temple' in world.settings.dungeon_shortcuts:
            # Reverse Shadow is broken with vanilla keys in both vanilla/MQ
            world.state.collect(ItemFactory('Small Key (Shadow Temple)', world))
            world.state.collect(ItemFactory('Small Key (Shadow Temple)', world))

    if (not world.keysanity or (world.empty_dungeons['Fire Temple'].empty and world.settings.shuffle_smallkeys != 'remove'))\
        and not world.dungeon_mq['Fire Temple']:
        world.state.collect(ItemFactory('Small Key (Fire Temple)', world))

    if world.settings.shuffle_ganon_bosskey == 'on_lacs':
        placed_items['ToT Light Arrows Cutscene'] = ItemFactory('Boss Key (Ganons Castle)', world)

    if world.settings.shuffle_ganon_bosskey in ('stones', 'medallions', 'dungeons', 'tokens', 'hearts', 'triforce'):
        placed_items['Gift from Sages'] = ItemFactory('Boss Key (Ganons Castle)', world)
        pool.extend(get_junk_item())
    else:
        placed_items['Gift from Sages'] = ItemFactory(IGNORE_LOCATION, world)

    if world.settings.junk_ice_traps == 'off':
        replace_max_item(pool, 'Ice Trap', 0)
    elif world.settings.junk_ice_traps == 'onslaught':
        for item in [item for item, weight in junk_pool_base] + ['Recovery Heart', 'Bombs (20)', 'Arrows (30)']:
            replace_max_item(pool, item, 0)

    for item, maximum in item_difficulty_max[world.settings.item_pool_value].items():
        replace_max_item(pool, item, maximum)

    world.distribution.alter_pool(world, pool)

    # Make sure our pending_junk_pool is empty. If not, remove some random junk here.
    if pending_junk_pool:
        for item in set(pending_junk_pool):
            # Ensure pending_junk_pool contents don't exceed values given by distribution file
            if world.distribution.item_pool and item in world.distribution.item_pool:
                while pending_junk_pool.count(item) > world.distribution.item_pool[item].count:
                    pending_junk_pool.remove(item)
                # Remove pending junk already added to the pool by alter_pool from the pending_junk_pool
                if item in pool:
                    count = min(pool.count(item), pending_junk_pool.count(item))
                    for _ in range(count):
                        pending_junk_pool.remove(item)

        remove_junk_pool, _ = zip(*junk_pool_base)
        # Omits Rupees (200) and Deku Nuts (10)
        remove_junk_pool = list(remove_junk_pool) + ['Recovery Heart', 'Bombs (20)', 'Arrows (30)', 'Ice Trap']

        junk_candidates = [item for item in pool if item in remove_junk_pool]
        while pending_junk_pool:
            pending_item = pending_junk_pool.pop()
            if not junk_candidates:
                raise RuntimeError("Not enough junk exists in item pool for %s (+%d others) to be added." % (pending_item, len(pending_junk_pool) - 1))
            junk_item = random.choice(junk_candidates)
            junk_candidates.remove(junk_item)
            pool.remove(junk_item)
            pool.append(pending_item)

    if world.settings.item_pool_value == 'ludicrous':
        # Replace all junk items with major items
        # Overrides plando'd junk items
        # Songs are in the unrestricted pool even if their fill is restricted. Filter from candidates
        duplicate_candidates = [item for item in ludicrous_items_extended if item in pool and (ItemInfo.items[item].type != 'Song' or world.settings.shuffle_song_items == 'any')]
        duplicate_candidates.extend(ludicrous_items_base)
        junk_items = [
            item for item in pool
            if item not in duplicate_candidates
            and ItemInfo.items[item].type != 'Shop'
            and ItemInfo.items[item].type != 'Song'
            and not ItemInfo.items[item].trade
            and item not in normal_bottles
            and item not in ludicrous_exclusions
        ]
        max_extra_copies = int(Decimal(len(junk_items) / len(duplicate_candidates)).to_integral_value(rounding=ROUND_UP))
        duplicate_items = [item for item in duplicate_candidates for _ in range(max_extra_copies)]
        pool = [item if item not in junk_items else duplicate_items.pop(0) for item in pool]
        # Handle bottles separately since only 4 can be obtained
        pool_bottles = 0
        pool_letters = 0
        for item in pool:
            if item == 'Rutos Letter':
                pool.remove(item)
                pool_bottles += 1
                pool_letters += 1
            if item in normal_bottles:
                pool.remove(item)
                pool_bottles += 1
        letter_adds = 0
        # No Rutos Letters in the pool could be due to open fountain or starting with one
        if pool_letters > 0:
            # Enforce max 2 Rutos Letters to balance out regular bottle availability
            letter_adds = min(2, max_extra_copies)
            for _ in range(letter_adds):
                pool.append('Rutos Letter')
        # Dynamically add bottles back to pool, accounting for starting items
        for _ in range(pool_bottles - letter_adds):
            bottle = random.choice(normal_bottles)
            pool.append(bottle)
        # Disabled locations use the #Junk group for fill.
        # Update pattern matcher since all normal junk is removed.
        item_groups['Junk'] = remove_junk_ludicrous_items
        world.distribution.distribution.search_groups['Junk'] = remove_junk_ludicrous_items
    else:
        # Fix for unit tests reusing globals after ludicrous pool mutates them
        item_groups['Junk'] = remove_junk_items
        world.distribution.distribution.search_groups['Junk'] = remove_junk_items

    world.distribution.collect_starters(world.state)

    if not world.settings.shuffle_individual_ocarina_notes:
        world.state.collect(ItemFactory('Ocarina A Button', world))
        world.state.collect(ItemFactory('Ocarina C up Button', world))
        world.state.collect(ItemFactory('Ocarina C down Button', world))
        world.state.collect(ItemFactory('Ocarina C left Button', world))
        world.state.collect(ItemFactory('Ocarina C right Button', world))

    return pool, placed_items