mtg/tools/bracket_check.py

#!/usr/bin/env python3
"""Check a decklist against Commander Bracket 3 + our house rules.

    python3 tools/bracket_check.py --deck decks/reaper-king-no-more
    python3 tools/bracket_check.py --deck decks/reaper-king-no-more decks/reaper-king-no-more/decks/no-mikaeus/decklist.mtg

Enforces:
  * <= 3 Game Changers                      (official)
  * no mass land denial                     (official)
  * extra turns sparse, never looping       (official)
  * NO two-card-in-a-vacuum infinite combos (our house rule, stricter)
  * singleton + 100 cards                   (format)
"""
import os, sys, json
from collections import Counter
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from cards import DB, load_decklist
from deckctx import DeckContext

MLD_TAGS   = {"mass-land-denial"}   # verified: the real Tagger slug, 114 cards
EXTRA_TURN = "extra-turn"
LIMIT_GC   = 3


def vacuum_combos(db, deck_names, commander):
    """Two-card infinite combos among our cards that need NO extra board state.

    Spellbook gives prerequisites per combo; a combo requiring creatures on the
    battlefield or a third enabler is a build-around, not a vacuum combo.
    """
    _, idx = db.combos
    pool = set(deck_names) | {commander}
    seen, flagged, buildarounds = set(), [], []
    for name in pool:
        for combo in idx.get(name, []):
            if combo["id"] in seen:
                continue
            uses = [u["card"]["name"] for u in combo["uses"]]
            if len(uses) != 2 or not set(uses) <= pool:
                continue
            seen.add(combo["id"])
            prereq = (combo.get("notablePrerequisites") or "").strip()
            infinite = any("Infinite" in p["feature"]["name"] or "wins the game" in p["feature"]["name"]
                           or "loses the game" in p["feature"]["name"] for p in combo["produces"])
            if not infinite:
                continue
            (flagged if not prereq else buildarounds).append((uses, prereq, combo))
    return flagged, buildarounds


def main(argv=None):
    argv = sys.argv[1:] if argv is None else argv
    ctx = DeckContext.from_args(argv)
    # any remaining positional arg overrides which decklist file to check,
    # while --deck still selects the deck (config, identity, blacklist)
    path = next((a for a in argv if not a.startswith("-")), None) or ctx.decklist_path
    db = DB(blacklist_path=ctx.blacklist_path)
    commander, main_deck = load_decklist(path)
    if not commander:
        sys.exit("no commander found -- decklist needs a '# Commander' section")

    print(f"COMMANDER: {commander}")
    print(f"DECK SIZE: {len(main_deck)} + 1 commander = {len(main_deck)+1}\n")

    ok = True

    # --- unknown cards ---
    unknown = [n for n in [commander] + main_deck if not db.get(n)]
    if unknown:
        ok = False
        print("!! UNKNOWN CARDS (typo or not in bulk data):")
        for n in unknown: print(f"   {n}")
        print()

    known = [db[n] for n in main_deck if db.get(n)]
    cmd = db.get(commander)

    # --- size + singleton ---
    if len(main_deck) + 1 != 100:
        ok = False
        print(f"!! SIZE: {len(main_deck)+1} cards, need exactly 100\n")
    dupes = {n: c for n, c in Counter(main_deck).items() if c > 1
             and db.get(n) and "Basic" not in db[n].type_line}
    if dupes:
        ok = False
        print("!! SINGLETON violated:", dupes, "\n")

    # --- color identity ---
    # Fall back to the configured deck's own commander identity (never a
    # hardcoded color combination) if this decklist's own commander card
    # wasn't found in the database.
    ci = cmd.color_identity if cmd else ctx.identity(db)
    off = [c.name for c in known if not c.color_identity <= ci]
    if off:
        ok = False
        print(f"!! OFF-IDENTITY (commander is {''.join(sorted(ci))}):")
        for n in off: print(f"   {n}")
        print()

    # --- blacklist (preference, not a bracket rule) ---
    bl = [c for c in known if c.name in db.blacklist] + \
         ([cmd] if cmd and cmd.name in db.blacklist else [])
    if bl:
        ok = False
        print(f"!! BLACKLISTED CARDS IN DECK: {len(bl)}  (personal preference, not a bracket rule)")
        for c in bl:
            print(f"   - {c.name}  -- {db.blacklist[c.name]}")
        print()

    # --- game changers ---
    gc = [c for c in known if c.game_changer] + ([cmd] if cmd and cmd.game_changer else [])
    status = "OK" if len(gc) <= LIMIT_GC else "!! OVER LIMIT"
    print(f"GAME CHANGERS: {len(gc)}/{LIMIT_GC}  {status}")
    for c in gc: print(f"   - {c.name}")
    if len(gc) > LIMIT_GC: ok = False
    print()

    # --- mass land denial ---
    mld = [c for c in known if c.tags & MLD_TAGS]
    print(f"MASS LAND DENIAL: {len(mld)}  {'OK' if not mld else '!! NOT ALLOWED IN B3'}")
    for c in mld: print(f"   - {c.name}")
    if mld: ok = False
    print()

    # --- extra turns ---
    et = [c for c in known if EXTRA_TURN in c.tags]
    print(f"EXTRA TURNS: {len(et)}  {'OK' if len(et) <= 1 else '?? keep sparse, never loop'}")
    for c in et: print(f"   - {c.name}")
    print()

    # --- combos ---
    vac, build = vacuum_combos(db, main_deck, commander)
    print(f"TWO-CARD INFINITE COMBOS IN A VACUUM: {len(vac)}  {'OK' if not vac else '!! HOUSE RULE VIOLATION'}")
    for uses, _, _ in vac:
        print(f"   - {' + '.join(uses)}")
    if vac: ok = False
    print()

    if build:
        print(f"two-card combos needing board state (ALLOWED, {len(build)}):")
        for uses, prereq, _ in build:
            print(f"   - {' + '.join(uses)}")
            for line in prereq.splitlines():
                print(f"       requires: {line}")
        print()

    print("=" * 58)
    print("BRACKET 3: PASS" if ok else "BRACKET 3: FAIL -- see !! above")
    return 0 if ok else 1


if __name__ == "__main__":
    sys.exit(main())