#!/usr/bin/env python3
"""Convert decklist.mgt -> Forge .dck format.

    python3 tools/to_dck.py --deck decks/reaper-king-no-more
    python3 tools/to_dck.py --deck decks/reaper-king-no-more [decklist.mgt] [-o ~/forge/decks/<slug>.dck]

Forge sections are [Commander], [Main], [Sideboard] (verified in DeckSection.java).
Card names must match Forge's own database, so this validates against
res/cardsfolder and reports anything Forge won't recognise BEFORE you sim.

Output filename and [metadata] Name= are both derived from the deck (slug /
config.yaml `name:`) -- never a hardcoded "reaper.dck" / deck title.
"""
import sys, os, re, zipfile
sys.path.insert(0, os.path.dirname(__file__))
from cards import load_decklist
from deckctx import DeckContext
from collections import Counter

def load_subs(subs_file, enabled=True):
    """Simulation-only card swaps for cards Forge's AI genuinely cannot pilot.

    Returns {real_card: stand_in}. See <deck>/sim_substitutions.yaml for the
    rationale and the deviations each swap introduces.
    """
    if not enabled or not subs_file or not os.path.exists(subs_file):
        return {}
    try:
        import yaml
    except ImportError:
        print("warning: pyyaml missing, substitutions skipped", file=sys.stderr)
        return {}
    d = yaml.safe_load(open(subs_file)) or {}
    return d.get("substitutions") or {}

FORGE = os.path.expanduser("~/forge")


def forge_card_names():
    """Every card name Forge knows, from its cardsfolder (dir or .zip)."""
    names = set()
    folder = os.path.join(FORGE, "res", "cardsfolder")
    zpath = os.path.join(folder, "cardsfolder.zip")
    if os.path.exists(zpath):
        with zipfile.ZipFile(zpath) as z:
            for n in z.namelist():
                if not n.endswith(".txt"):
                    continue
                with z.open(n) as f:
                    for line in f:
                        line = line.decode("utf-8", "ignore").strip()
                        if line.startswith("Name:"):
                            names.add(line[5:].strip()); break
    for root, _, files in os.walk(folder):
        for fn in files:
            if not fn.endswith(".txt"):
                continue
            try:
                with open(os.path.join(root, fn), encoding="utf-8", errors="ignore") as f:
                    for line in f:
                        if line.startswith("Name:"):
                            names.add(line[5:].strip()); break
            except OSError:
                pass
    return names


def main():
    ctx = DeckContext.from_args()
    args = [a for a in sys.argv[1:]]
    out = args[args.index("-o") + 1] if "-o" in args else \
        os.path.join(FORGE, "decks", ctx.dck_filename())
    src = next((a for a in args if a.endswith(".mgt")), ctx.decklist_path)

    commander, deck = load_decklist(src)

    subs_file = ctx.path(ctx.config.get("sim_substitutions_file", "sim_substitutions.yaml"))
    subs = load_subs(subs_file, enabled="--no-subs" not in args)
    applied = {}
    if subs:
        present = set(deck)
        swapped = []            # NB: not `out` -- that's the output path
        for n in deck:
            t = subs.get(n)
            # never substitute into a duplicate: that would break singleton
            if t and t not in present:
                applied[n] = t
                present.add(t)
                swapped.append(t)
            else:
                if t:
                    print(f"note: not substituting {n} -> {t} "
                          f"({t} already in deck)", file=sys.stderr)
                swapped.append(n)
        deck = swapped
    if applied:
        print(f"substituted {len(applied)} AI-unpilotable card(s) for simulation:",
              file=sys.stderr)
        for a, b in applied.items():
            print(f"   {a}  ->  {b}", file=sys.stderr)
        print("   (per-card stats for these describe the STAND-IN, not the real card)",
              file=sys.stderr)
    known = forge_card_names()
    if known:
        missing = sorted({n for n in [commander] + deck if n not in known})
        if missing:
            print(f"!! {len(missing)} card(s) Forge does not recognise:", file=sys.stderr)
            for m in missing:
                print(f"   {m}", file=sys.stderr)
            print("   (fix the name in decklist.mgt, or Forge will drop it)\n", file=sys.stderr)
    else:
        print("warning: could not read Forge's card list; skipping validation", file=sys.stderr)

    lines = ["[metadata]", f"Name={ctx.forge_metadata_name()}", "", "[Commander]", f"1 {commander}", "", "[Main]"]
    for name, count in sorted(Counter(deck).items()):
        lines.append(f"{count} {name}")
    lines += ["", "[Sideboard]", ""]

    os.makedirs(os.path.dirname(out), exist_ok=True)
    open(out, "w").write("\n".join(lines) + "\n")
    print(f"wrote {out}  ({len(deck)} + 1 commander)")
    return 0


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