File size: 20,981 Bytes
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
 
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
 
 
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
 
 
 
 
 
 
 
7b94ee0
e9b16be
7b94ee0
 
 
 
 
 
 
 
e9b16be
7b94ee0
 
 
 
e9b16be
7b94ee0
 
e9b16be
 
7b94ee0
 
 
e9b16be
 
 
 
 
 
 
 
 
7b94ee0
 
 
 
 
e9b16be
 
7b94ee0
e9b16be
 
 
7b94ee0
 
e9b16be
7b94ee0
 
 
 
e9b16be
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
 
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
 
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
e9b16be
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
 
 
7b94ee0
 
 
 
e9b16be
 
 
 
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
 
7b94ee0
 
 
 
 
 
e9b16be
 
 
7b94ee0
 
 
 
e9b16be
 
 
7b94ee0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
e9b16be
7b94ee0
 
 
 
 
 
 
 
e9b16be
 
 
7b94ee0
e9b16be
 
7b94ee0
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
#!/usr/bin/env python3
"""d1 vs d1 blackjack battle.

Two llama.cpp servers, each hosting a LiquidAI d1-3B decision model, play
blackjack against a rule-based dealer. Every decision (bet size + hit / stand /
double) is a /v1/systemone query. The complete battle is written as JSON and
rendered into a static web page by build_site.py.

Usage:
    python3 blackjack.py --rounds 12 --out battle.json
"""
import argparse
import json
import random
import time
import urllib.error
import urllib.request
from datetime import datetime, timezone
from pathlib import Path

SUITS = ["♠", "♥", "♦", "♣"]
RANKS = ["A", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K"]
RANK_VALUE = {r: (11 if r == "A" else 10 if r in ("10", "J", "Q", "K") else int(r)) for r in RANKS}

DECKS = 6
BASE_BET = 10
START_BANKROLL = 1000
BET_FRACTIONS = {"min": 0.50, "standard": 0.70, "max": 1.00}

AGENTS = [
    {
        "id": "a",
        "name": "阿保",
        "style": "保守算牌派",
        "description": "以保住本金為第一優先,只有在牌面明顯有利時才加注,遇到風險寧可停牌。",
        "url": "http://127.0.0.1:8081",
    },
    {
        "id": "b",
        "name": "阿衝",
        "style": "激進壓迫派",
        "description": "相信進攻是最好的防守,喜歡加倍與大注,願意為了期望值承擔波動。",
        "url": "http://127.0.0.1:8082",
    },
]

RULES = {
    "decks": DECKS,
    "dealer": "莊家軟 17 停牌 (S17)",
    "blackjack_pays": "3:2",
    "double": "僅限硬 9–11 或軟 13–18 時加倍,加倍後只補一張",
    "split": "本局不開放分牌",
    "insurance": "不開放保險",
    "reshuffle": "剩餘牌數低於 25% 時重洗",
    "start_bankroll": START_BANKROLL,
    "betting": "注碼依當前資金比例:小注 50%、大注 70%、全押 100%(取整到 10)",
    "rebuy": "無補充籌碼,兩邊都歸零才結束",
}


def make_shoe(rng):
    shoe = [(r, s) for _ in range(DECKS) for s in SUITS for r in RANKS]
    rng.shuffle(shoe)
    return shoe


def card_str(card):
    return f"{card[0]}{card[1]}"


def hand_value(cards):
    total = sum(RANK_VALUE[r] for r, _ in cards)
    soft_aces = sum(1 for r, _ in cards if r == "A")
    while total > 21 and soft_aces:
        total -= 10
        soft_aces -= 1
    return total, soft_aces > 0


def is_blackjack(cards):
    return len(cards) == 2 and hand_value(cards)[0] == 21


def hi_lo(card):
    r = card[0]
    if r in ("2", "3", "4", "5", "6"):
        return 1
    if r in ("10", "J", "Q", "K", "A"):
        return -1
    return 0


def shoe_state(shoe, running_count):
    remaining = len(shoe)
    decks_left = max(remaining / 52.0, 0.15)
    counts = {r: 0 for r in RANKS}
    for r, _ in shoe:
        counts[r] += 1
    return {
        "decks": DECKS,
        "remaining_cards": remaining,
        "penetration_pct": round(100 * (1 - remaining / (DECKS * 52))),
        "cards_left_by_rank": counts,
        "hi_lo_running_count": running_count,
        "true_count": round(running_count / decks_left, 2),
    }


class D1Client:
    def __init__(self, agent):
        self.agent = agent
        self.url = agent["url"].rstrip("/")
        self.calls = 0
        self.total_ms = 0

    def ask(self, state, questions, retries=2):
        payload = json.dumps({"state": state, "questions": questions}).encode()
        last_err = None
        for _ in range(retries + 1):
            started = time.time()
            req = urllib.request.Request(
                f"{self.url}/v1/systemone",
                data=payload,
                headers={"Content-Type": "application/json"},
            )
            try:
                with urllib.request.urlopen(req, timeout=120) as resp:
                    body = json.loads(resp.read())
                elapsed = int((time.time() - started) * 1000)
                self.calls += 1
                self.total_ms += elapsed
                return body["answers"], elapsed, None
            except Exception as exc:  # noqa: BLE001
                last_err = f"{type(exc).__name__}: {exc}"
                time.sleep(0.4)
        return None, 0, last_err


def pick(answers, key, valid):
    ans = (answers or {}).get(key) or {}
    choice = ans.get("choice")
    if choice not in valid:
        return None
    return ans


def draw(shoe, count):
    cards = [shoe.pop() for _ in range(min(count, len(shoe)))]
    return cards


def fallback_action(total, soft, allowed):
    if "double" in allowed and total in (10, 11):
        return "double"
    if soft and total >= 19:
        return "stand"
    if total >= 17:
        return "stand"
    return "hit"


def play_hand(client, shoe, player, hand, dealer_up, running_count, rng):
    steps = []
    while True:
        total, soft = hand_value(hand["cards"])
        if total >= 21:
            break
        allowed = ["hit", "stand"]
        double_spot = (not soft and 9 <= total <= 11) or (soft and 13 <= total <= 18)
        if len(hand["cards"]) == 2 and player["bankroll"] >= hand["bet"] and double_spot:
            allowed.append("double")

        state = {
            "game": "blackjack",
            "you": {
                "name": client.agent["name"],
                "style": client.agent["style"],
                "personality": client.agent["description"],
                "bankroll": player["bankroll"],
            },
            "hand": {
                "cards": [card_str(c) for c in hand["cards"]],
                "total": total,
                "soft": soft,
                "is_pair": len(hand["cards"]) == 2 and hand["cards"][0][0] == hand["cards"][1][0],
            },
            "dealer_upcard": card_str(dealer_up),
            "bet": hand["bet"],
            "allowed_actions": allowed,
            "shoe": shoe_state(shoe, running_count),
            "rules": RULES,
        }
        criteria = {
            "hit": "再補一張牌:點數偏低、需要往 17 點以上推進時使用",
            "stand": "停牌:點數已接近 21,或再補牌爆牌風險過高時使用",
        }
        if "double" in allowed:
            criteria["double"] = "加倍下注:再多押一倍且只補一張,通常用在 9、10、11 點這種有把握的局面"
        cards_text = " ".join(card_str(c) for c in hand["cards"])
        questions = {
            "action": {
                "type": "choice",
                "instructions": (
                    f"你是 {client.agent['name']},風格「{client.agent['style']}」:"
                    f"{client.agent['description']} "
                    "你在玩 21 點,目標是讓手牌點數盡量接近 21 但不超過,並贏過莊家。"
                    f"你的手牌是 {cards_text},合計 {total} 點"
                    f"({'軟牌,A 可算 11 或 1' if soft else '硬牌'})。"
                    f"莊家明牌是 {card_str(dealer_up)}。現在只能選一個動作,請選長期期望值最高的。"
                ),
                "criteria": criteria,
            },
            "risk": {
                "type": "score",
                "instructions": "以你的風格判斷,現在這個局面對你有多不利?",
                "criteria": ["非常有利", "稍微有利", "有點不利", "非常不利"],
            },
        }
        answers, latency, err = client.ask(state, questions)
        decision = pick(answers, "action", allowed)
        if decision is None:
            if not allowed:
                break
            action = fallback_action(total, soft, allowed)
            decision = {
                "type": "choice",
                "choice": action,
                "probabilities": {a: (1.0 if a == action else 0.0) for a in allowed},
                "confidence": 0.0,
                "fallback": True,
                "error": err,
            }
        action = decision["choice"]
        step = {
            "type": "action",
            "cards": [card_str(c) for c in hand["cards"]],
            "total": total,
            "soft": soft,
            "dealer_up": card_str(dealer_up),
            "allowed": allowed,
            "decision": decision,
            "risk": (answers or {}).get("risk"),
            "latency_ms": latency,
            "drawn": None,
            "total_after": total,
        }
        steps.append(step)

        if action == "stand":
            break
        if action == "double":
            player["bankroll"] -= hand["bet"]
            hand["bet"] *= 2
            hand["doubled"] = True
            new_card = draw(shoe, 1)[0]
            running_count += hi_lo(new_card)
            step["drawn"] = card_str(new_card)
            hand["cards"].append(new_card)
            hand["total"], hand["soft"] = hand_value(hand["cards"])
            step["total_after"] = hand["total"]
            break
        new_card = draw(shoe, 1)[0]
        running_count += hi_lo(new_card)
        step["drawn"] = card_str(new_card)
        hand["cards"].append(new_card)
        hand["total"], hand["soft"] = hand_value(hand["cards"])
        step["total_after"] = hand["total"]
        if hand["total"] > 21:
            break

    hand["total"], hand["soft"] = hand_value(hand["cards"])
    hand["bust"] = hand["total"] > 21
    hand["blackjack"] = is_blackjack(hand["cards"]) and not hand["doubled"]
    return running_count, steps


def settle(hand, dealer_total, dealer_blackjack, dealer_bust):
    if hand["bust"]:
        return "lose", -hand["bet"]
    if hand["blackjack"] and not dealer_blackjack:
        return "blackjack", int(hand["bet"] * 1.5)
    if dealer_blackjack and not hand["blackjack"]:
        return "lose", -hand["bet"]
    if dealer_bust:
        return "win", hand["bet"]
    if hand["total"] > dealer_total:
        return "win", hand["bet"]
    if hand["total"] < dealer_total:
        return "lose", -hand["bet"]
    return "push", 0


def ask_bet(client, player, dealer_up_hint, shoe, running_count):
    state = {
        "game": "blackjack",
        "you": {
            "name": client.agent["name"],
            "style": client.agent["style"],
            "personality": client.agent["description"],
            "bankroll": player["bankroll"],
        },
        "phase": "betting",
        "base_bet": BASE_BET,
        "shoe": shoe_state(shoe, running_count),
        "rules": RULES,
    }
    questions = {
        "bet": {
            "type": "choice",
            "instructions": (
                f"你是 {client.agent['name']},風格是「{client.agent['style']}」:"
                f"{client.agent['description']} 新的一局要下注了,"
                "請依資金、剩餘牌組成與真數決定注碼。"
            ),
            "criteria": {
                "min": "小注:押上目前資金的一半",
                "standard": "大注:押上目前資金的 70%",
                "max": "全押:把目前資金全部押上",
            },
        },
        "confidence": {
            "type": "score",
            "instructions": "你對這一注的信心有多高?",
            "criteria": ["沒信心", "普通", "有信心", "非常有信心"],
        },
    }
    answers, latency, err = client.ask(state, questions)
    decision = pick(answers, "bet", ["min", "standard", "max"])
    if decision is None:
        decision = {
            "choice": "min",
            "probabilities": {"min": 1.0, "standard": 0.0, "max": 0.0},
            "confidence": 0.0,
            "fallback": True,
            "error": err,
        }
    bankroll = player["bankroll"]
    fraction = BET_FRACTIONS.get(decision["choice"], 0.50)
    amount = int(bankroll * fraction)
    if amount >= BASE_BET:
        amount = max(BASE_BET, int(round(amount / 10.0)) * 10)
    bet = min(bankroll, max(amount, BASE_BET if bankroll >= BASE_BET else bankroll))
    if bet < BASE_BET:
        bet = bankroll
    if bet <= 0:
        bet = bankroll
    return {
        "decision": decision,
        "bet": max(bet, 0),
        "confidence": (answers or {}).get("confidence"),
        "latency_ms": latency,
    }


def run(rounds, seed, out_path, until_broke=True, max_rounds=500, start_bankroll=START_BANKROLL):
    rng = random.Random(seed)
    shoe = make_shoe(rng)
    running_count = 0
    players = [
        {"id": a["id"], "name": a["name"], "style": a["style"], "bankroll": start_bankroll}
        for a in AGENTS
    ]
    peaks = {p["id"]: start_bankroll for p in players}
    bust_round = {}
    clients = {a["id"]: D1Client(a) for a in AGENTS}
    started = time.time()
    history = []
    limit = max_rounds if until_broke else rounds
    n = 0

    while True:
        if until_broke and all(p["bankroll"] <= 0 for p in players):
            break
        if n >= limit:
            break
        n += 1

        if len(shoe) < DECKS * 52 * 0.25:
            shoe = make_shoe(rng)
            running_count = 0

        active = [a for a in AGENTS if next(p for p in players if p["id"] == a["id"])["bankroll"] > 0]
        events = []
        for a in AGENTS:
            if a not in active:
                player = next(p for p in players if p["id"] == a["id"])
                events.append(f"{player['name']} 資金為 0,本局無法下注")

        bets = {}
        for a in active:
            player = next(p for p in players if p["id"] == a["id"])
            bets[a["id"]] = ask_bet(clients[a["id"]], player, None, shoe, running_count)

        hands = {}
        for a in active:
            player = next(p for p in players if p["id"] == a["id"])
            hands[a["id"]] = {
                "cards": draw(shoe, 2),
                "bet": bets[a["id"]]["bet"],
                "doubled": False,
            }
            running_count += sum(hi_lo(c) for c in hands[a["id"]]["cards"])
            player["bankroll"] -= hands[a["id"]]["bet"]

        dealer_cards = draw(shoe, 2)
        running_count += sum(hi_lo(c) for c in dealer_cards)
        dealer_up, dealer_hole = dealer_cards[0], dealer_cards[1]
        dealer_blackjack = is_blackjack(dealer_cards)
        peek = RANK_VALUE[dealer_up[0]] in (10, 11)
        if peek:
            events.append("莊家明牌為 A 或 10 點,進行暗牌確認")

        round_rec = {
            "n": n,
            "shoe_before": shoe_state(shoe, running_count),
            "dealer_up": card_str(dealer_up),
            "dealer_hole": card_str(dealer_hole),
            "dealer_revealed": False,
            "dealer": None,
            "events": events,
            "players": [],
        }

        if dealer_blackjack:
            events.append("莊家直接拿到 Blackjack,本局立即結束")
            round_rec["dealer_revealed"] = True
            round_rec["dealer"] = {
                "cards": [card_str(c) for c in dealer_cards],
                "total": 21,
                "soft": hand_value(dealer_cards)[1],
                "blackjack": True,
                "bust": False,
            }
        else:
            for a in active:
                hand = hands[a["id"]]
                player = next(p for p in players if p["id"] == a["id"])
                running_count, steps = play_hand(
                    clients[a["id"]], shoe, player, hand, dealer_up, running_count, rng
                )
                hand["steps"] = steps
                hand["player_id"] = a["id"]

        if not dealer_blackjack:
            dealer_total, dealer_soft = hand_value(dealer_cards)
            if any(not h["bust"] for h in hands.values()):
                if peek:
                    events.append("確認結果:莊家沒有 Blackjack")
                while dealer_total < 17:
                    card = draw(shoe, 1)[0]
                    running_count += hi_lo(card)
                    dealer_cards.append(card)
                    dealer_total, dealer_soft = hand_value(dealer_cards)
                    events.append(f"莊家補牌 {card_str(card)} → {dealer_total} 點")
                events.append(f"莊家最終 {dealer_total} 點" + (",爆牌" if dealer_total > 21 else ""))
            else:
                events.append("所有玩家都爆牌,莊家不補牌")
            round_rec["dealer_revealed"] = True
            round_rec["dealer"] = {
                "cards": [card_str(c) for c in dealer_cards],
                "total": dealer_total,
                "soft": dealer_soft,
                "blackjack": False,
                "bust": dealer_total > 21,
            }

        dealer_total = round_rec["dealer"]["total"]
        dealer_bust = round_rec["dealer"]["bust"]

        for a in active:
            player = next(p for p in players if p["id"] == a["id"])
            hand = hands[a["id"]]
            hand["blackjack"] = is_blackjack(hand["cards"]) and not hand["doubled"]
            hand["bust"] = hand_value(hand["cards"])[0] > 21
            result, net = settle(hand, dealer_total, dealer_blackjack, dealer_bust)
            hand.update(
                {
                    "cards": [card_str(c) for c in hand["cards"]],
                    "total": hand_value(hand["cards"])[0],
                    "soft": hand_value(hand["cards"])[1],
                    "blackjack": is_blackjack(hand["cards"]) and not hand["doubled"],
                    "bust": hand_value(hand["cards"])[0] > 21,
                    "result": result,
                    "net": net,
                    "bet_decision": bets[a["id"]],
                }
            )
            player["bankroll"] += hand["bet"] + net
            if player["bankroll"] < 0:
                player["bankroll"] = 0
            peaks[a["id"]] = max(peaks[a["id"]], player["bankroll"])
            hand["bankroll_after"] = player["bankroll"]
            hand["id"] = a["id"]
            hand["name"] = a["name"]
            hand["style"] = a["style"]
            hand["peak_bankroll"] = peaks[a["id"]]
            if player["bankroll"] == 0 and a["id"] not in bust_round:
                bust_round[a["id"]] = n
                events.append(f"{player['name']} 資金歸零,破產出局")
            round_rec["players"].append(hand)

        round_rec["shoe_after"] = shoe_state(shoe, running_count)
        history.append(round_rec)
        print(
            f"round {n:02d} | dealer {dealer_total} | "
            + " | ".join(
                f"{h['name']} {h['total']} {h['result']} net {h['net']:+d} bank {h['bankroll_after']}"
                for h in round_rec["players"]
            ),
            flush=True,
        )

    meta = {
        "title": "d1 × d1 21 點:破產對決",
        "subtitle": "兩個 LiquidAI d1-3B 決策模型,用 llama.cpp 一路打到雙方資金歸零",
        "created_at": datetime.now(timezone.utc).astimezone().isoformat(timespec="seconds"),
        "seed": seed,
        "model": "LiquidAI/d1-3B-GGUF",
        "quant": "Q8_0",
        "llama_build": "b11786 (0.7.0-dev)",
        "rules": RULES,
        "start_bankroll": start_bankroll,
        "bet_fractions": BET_FRACTIONS,
        "end_reason": "both_broke" if all(p["bankroll"] <= 0 for p in players) else "round_limit",
        "agents": [
            {
                **a,
                "final_bankroll": next(p for p in players if p["id"] == a["id"])["bankroll"],
                "peak_bankroll": peaks[a["id"]],
                "bust_round": bust_round.get(a["id"]),
                "rounds_played": sum(1 for r in history if any(x["id"] == a["id"] for x in r["players"])),
            }
            for a in AGENTS
        ],
        "rounds_played": len(history),
        "duration_sec": round(time.time() - started, 2),
        "inference": {
            a["id"]: {
                "calls": clients[a["id"]].calls,
                "avg_latency_ms": round(clients[a["id"]].total_ms / max(clients[a["id"]].calls, 1)),
            }
            for a in AGENTS
        },
    }
    data = {"meta": meta, "rounds": history}
    out = Path(out_path)
    out.parent.mkdir(parents=True, exist_ok=True)
    out.write_text(json.dumps(data, ensure_ascii=False, indent=1), encoding="utf-8")
    print(f"wrote {out} ({out.stat().st_size / 1024:.1f} KiB) | end: {meta['end_reason']} | rounds: {len(history)}")
    return data


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("--rounds", type=int, default=12)
    parser.add_argument("--seed", type=int, default=20261021)
    parser.add_argument("--out", default="battle.json")
    parser.add_argument("--max-rounds", type=int, default=500)
    parser.add_argument("--start-bankroll", type=int, default=START_BANKROLL)
    parser.add_argument("--fixed-rounds", action="store_true", help="stop after --rounds instead of playing until both are broke")
    args = parser.parse_args()
    run(args.rounds, args.seed, args.out, until_broke=not args.fixed_rounds,
        max_rounds=args.max_rounds, start_bankroll=args.start_bankroll)


if __name__ == "__main__":
    main()