Dune/tests/nexus-ixian-replacement.test.ts

import assert from 'node:assert/strict';
import test from 'node:test';
import { baseDeck, choamDeck, ixDeck, treacheryDeck, type Card } from '../game/cards';
import { richeseCards } from '../game/richese-cards';
import {
  IxianReplacementError,
  closeIxianReplacementSource,
  createIxianReplacementSource,
  initialIxianReplacementCursor,
  ixianReplacementEvent,
  validateIxianReplacementHistory,
  validateIxianReplacementSource,
  type IxianReplacementContext,
  type IxianReplacementReceipt,
} from '../game/nexus-ixian-replacement';

const [purchased, older, top, unsold] = baseDeck();
const parent = 'original-native-paid-sale-parent';

function context(): IxianReplacementContext {
  return {
    status: 'playing', phase: 3, turn: 1, sequence: 0,
    expansions: [], richese: false, advanced: false,
    auction: { cards: [{ ...purchased }, { ...unsold }], index: 0, bidder: 'buyer', bid: 4 },
    richeseAuction: null,
    sale: { winner: 'buyer', amount: 4, free: false, origin: 'normal', seller: null },
    specialPurchase: null,
    players: [
      { id: 'buyer', hand: [{ ...older }, { ...purchased }], handLimit: 4 },
      { id: 'rival', hand: [], handLimit: 4 },
    ],
    physicalCards: [{ ...older }, { ...purchased }, { ...top }, { ...unsold }],
  };
}
function purchaseContext(
  card: Card, expansions: readonly string[], richese = false,
): IxianReplacementContext {
  const ctx = context();
  ctx.expansions = expansions;
  ctx.richese = richese;
  ctx.auction!.cards = [{ ...card }];
  ctx.players = [{ ...ctx.players[0], hand: [{ ...card }] }, ctx.players[1]];
  ctx.physicalCards = [{ ...card }];
  return ctx;
}
function source(ctx: IxianReplacementContext = context()) {
  return createIxianReplacementSource(
    ctx, ixianReplacementEvent(ctx.turn, ctx.specialPurchase?.buyer ?? 'buyer',
      ctx.sequence, ctx.specialPurchase ? 0 : ctx.auction?.index ?? 0), parent,
  );
}

function nativeContext(origin: 'cache' | 'blackMarket'): IxianReplacementContext {
  const card = origin === 'cache' ? richeseCards()[0] : purchased;
  const ctx = context();
  ctx.expansions = ['choam'];
  ctx.richese = true;
  ctx.advanced = origin === 'blackMarket';
  ctx.auction = null;
  ctx.richeseAuction = {
    event: `native-${origin}-auction`, cardId: card.id, source: origin, owner: 'rival',
    outcome: { kind: 'sold', winner: 'buyer', amount: 7 },
  };
  ctx.sale = { winner: 'buyer', amount: 7, free: false, origin, seller: 'rival' };
  ctx.players = [{ ...ctx.players[0], hand: [{ ...older }, { ...card }] }, ctx.players[1]];
  ctx.physicalCards = [{ ...older }, { ...card }, { ...top }];
  return ctx;
}

const printedKarama = baseDeck().find(card => card.effect === 'karama')!;
const directTarget = richeseCards()[1];

function specialContext(ctx: IxianReplacementContext = context()): IxianReplacementContext {
  ctx.expansions = ['choam'];
  ctx.richese = true;
  ctx.advanced = true;
  ctx.specialPurchase = {
    buyer: 'rival', cardId: directTarget.id, karama: printedKarama.id,
    amount: 3, turn: ctx.turn, phase: 3,
  };
  ctx.players = ctx.players.map(player => player.id === 'rival'
    ? { ...player, hand: [...player.hand, directTarget] } : player);
  // The delivered target is held; the already-spent printed Karama remains in discard custody.
  ctx.physicalCards = [...ctx.physicalCards, directTarget, printedKarama];
  return ctx;
}

void test('committed direct Richese purchase with no auction closes the exact paid cache card', () => {
  const ctx = specialContext();
  ctx.auction = null;
  ctx.sale = null;
  const original = source(ctx);
  assert.equal(original.buyer, 'rival');
  assert.deepEqual(original.card, directTarget);
  assert.equal(original.amount, 3);
  assert.equal(original.free, false);
  assert.equal(original.auctionIndex, 0);
  validateIxianReplacementSource(ctx, JSON.parse(JSON.stringify(original)), parent);
  for (const outcome of ['use', 'pass'] as const) {
    const closed = closeIxianReplacementSource(
      original, outcome, outcome === 'use' ? top : null, initialIxianReplacementCursor(),
    );
    assert.equal(closed.receipt.outcome, outcome);
    assert.deepEqual(closed.receipt.replacement, outcome === 'use' ? top : null);
    assert.throws(() => closeIxianReplacementSource(original, 'pass', null, closed.cursor), IxianReplacementError);
    validateIxianReplacementHistory(JSON.parse(JSON.stringify([closed.receipt])), closed.cursor, [older]);
  }
});

void test('direct receipt outranks unrelated delivered normal and native lots without changing their sources', () => {
  for (const origin of ['normal', 'cache', 'blackMarket'] as const) {
    const ctx = origin === 'normal' ? context() : nativeContext(origin);
    if (ctx.auction) ctx.auction = { ...ctx.auction, cards: [unsold, purchased], index: 1 };
    const olderSource = source(ctx);
    specialContext(ctx);
    const direct = source(ctx);
    assert.equal(direct.buyer, 'rival');
    assert.equal(direct.card.id, directTarget.id);
    assert.equal(direct.amount, 3);
    assert.equal(direct.free, false);
    assert.equal(direct.auctionIndex, 0);
    assert.throws(() => validateIxianReplacementSource(ctx, olderSource, parent), IxianReplacementError);
    ctx.specialPurchase = null;
    // Restoring the suspended authority still validates its original price, target and index.
    validateIxianReplacementSource(ctx, olderSource, parent);
    assert.throws(() => validateIxianReplacementSource(ctx, direct, parent), IxianReplacementError);
  }
  const priorFree = context();
  priorFree.auction = { ...priorFree.auction!, bid: 0 };
  priorFree.sale = { ...priorFree.sale!, amount: 0, free: true };
  const oldFreeSource = source(priorFree);
  specialContext(priorFree);
  assert.equal(source(priorFree).amount, 3);
  assert.equal(source(priorFree).free, false);
  priorFree.specialPurchase = null;
  validateIxianReplacementSource(priorFree, oldFreeSource, parent);
});

void test('direct purchase rejects stale authority, wrong mode, noncache targets and unspent or false costs', () => {
  const ctx = specialContext();
  const purchase = ctx.specialPurchase!;
  const original = source(ctx);
  const variants: IxianReplacementContext[] = [
    { ...ctx, status: 'finished' },
    { ...ctx, phase: 4 },
    { ...ctx, turn: 2 },
    { ...ctx, specialPurchase: { ...purchase, turn: 2 } },
    { ...ctx, specialPurchase: { ...purchase, phase: 4 as never } },
    { ...ctx, advanced: false },
    { ...ctx, richese: false },
    { ...ctx, expansions: [] },
    { ...ctx, specialPurchase: { ...purchase, amount: 0 as never } },
    { ...ctx, specialPurchase: { ...purchase, amount: 4 as never } },
    { ...ctx, specialPurchase: { ...purchase, buyer: 'unseated' } },
    { ...ctx, specialPurchase: { ...purchase, cardId: older.id } },
    { ...ctx, specialPurchase: { ...purchase, cardId: richeseCards()[0].id } },
    { ...ctx, specialPurchase: { ...purchase, karama: purchased.id } },
    { ...ctx, specialPurchase: { ...purchase, karama: directTarget.id } },
    { ...ctx, physicalCards: ctx.physicalCards.filter(card => card.id !== printedKarama.id) },
    { ...ctx, physicalCards: ctx.physicalCards.filter(card => card.id !== directTarget.id) },
    { ...ctx, physicalCards: [...ctx.physicalCards, printedKarama] },
    { ...ctx, physicalCards: ctx.physicalCards.map(card =>
      card.id === printedKarama.id ? { ...card, effect: 'fabricated' } : card) },
    { ...ctx, players: ctx.players.map(player => player.id === 'rival'
      ? { ...player, hand: [...player.hand, printedKarama] } : player) },
    { ...ctx, players: ctx.players.map(player => player.id === 'rival'
      ? { ...player, hand: [] } : { ...player, hand: [...player.hand, directTarget] }) },
    { ...ctx, players: ctx.players.map(player => player.id === 'buyer'
      ? { ...player, hand: [...player.hand, directTarget] } : player) },
    { ...ctx, players: ctx.players.map(player => player.id === 'rival'
      ? { ...player, hand: [{ ...directTarget, name: 'Altered cache card' }] } : player),
      physicalCards: ctx.physicalCards.map(card => card.id === directTarget.id
        ? { ...card, name: 'Altered cache card' } : card) },
  ];
  for (const invalid of variants) {
    assert.throws(() => source(invalid), IxianReplacementError);
    assert.throws(() => validateIxianReplacementSource(invalid, original, parent), IxianReplacementError);
  }
  assert.throws(() => validateIxianReplacementSource(
    { ...ctx, sequence: 1 }, original, parent,
  ), IxianReplacementError);
  assert.throws(() => validateIxianReplacementSource(ctx, original, 'changed-parent'), IxianReplacementError);
  assert.throws(() => createIxianReplacementSource(ctx, 'stale-direct-event', parent), IxianReplacementError);
});

void test('a different owned cache card cannot retarget an existing direct receipt', () => {
  const ctx = specialContext();
  const original = source(ctx);
  const another = richeseCards()[0];
  ctx.players = ctx.players.map(player => player.id === 'rival'
    ? { ...player, hand: [...player.hand, another] } : player);
  ctx.physicalCards = [...ctx.physicalCards, another];
  ctx.specialPurchase = { ...ctx.specialPurchase!, cardId: another.id };
  assert.throws(() => validateIxianReplacementSource(ctx, original, parent), IxianReplacementError);
});

void test('native cache and Black Market purchases close exact delivered cards once for Use or Pass', () => {
  for (const origin of ['cache', 'blackMarket'] as const) {
    const ctx = nativeContext(origin);
    const original = source(ctx);
    const delivered = ctx.players[0].hand.find(card => card.id === ctx.richeseAuction!.cardId)!;
    assert.deepEqual(original.card, delivered);
    assert.equal(original.amount, 7);
    assert.equal(original.free, false);
    assert.equal(original.auctionIndex, 0);
    validateIxianReplacementSource(ctx, JSON.parse(JSON.stringify(original)), parent);
    for (const outcome of ['use', 'pass'] as const) {
      const closed = closeIxianReplacementSource(
        original, outcome, outcome === 'use' ? top : null, initialIxianReplacementCursor(),
      );
      assert.equal(closed.receipt.outcome, outcome);
      assert.deepEqual(closed.receipt.replacement, outcome === 'use' ? top : null);
      assert.throws(() => closeIxianReplacementSource(original, 'pass', null, closed.cursor), IxianReplacementError);
      assert.throws(() => closeIxianReplacementSource(original, 'use', top, closed.cursor), IxianReplacementError);
      // A later census need not retain the purchased or drawn card at its old location.
      validateIxianReplacementHistory(
        JSON.parse(JSON.stringify([closed.receipt])), closed.cursor, [older],
      );
    }
  }
});

void test('successive single native lots use the independent sequence without inventing normal rows', () => {
  const cache = nativeContext('cache');
  const first = closeIxianReplacementSource(source(cache), 'pass', null, initialIxianReplacementCursor());
  const blackMarket = nativeContext('blackMarket');
  blackMarket.sequence = first.cursor.sequence;
  const second = closeIxianReplacementSource(source(blackMarket), 'use', top, first.cursor);
  assert.equal(first.receipt.source.auctionIndex, 0);
  assert.equal(second.receipt.source.auctionIndex, 0);
  assert.notEqual(first.receipt.source.event, second.receipt.source.event);
  validateIxianReplacementHistory([first.receipt, second.receipt], second.cursor);
});

void test('native purchase authority rejects missing, open, unbid, mismatched and competing lots', () => {
  for (const origin of ['cache', 'blackMarket'] as const) {
    const ctx = nativeContext(origin);
    const lot = ctx.richeseAuction!;
    const original = source(ctx);
    const variants: IxianReplacementContext[] = [
      { ...ctx, richeseAuction: null },
      { ...ctx, richeseAuction: { ...lot, outcome: null } },
      { ...ctx, richeseAuction: { ...lot, outcome: { kind: 'unbid' } } },
      { ...ctx, richeseAuction: { ...lot, outcome: { kind: 'sold', winner: 'buyer', amount: 0 } } },
      { ...ctx, richeseAuction: { ...lot, outcome: { kind: 'sold', winner: 'rival', amount: 7 } } },
      { ...ctx, richeseAuction: { ...lot, outcome: { kind: 'sold', winner: 'buyer', amount: 8 } } },
      { ...ctx, richeseAuction: { ...lot, source: origin === 'cache' ? 'blackMarket' : 'cache' } },
      { ...ctx, richeseAuction: { ...lot, cardId: unsold.id } },
      { ...ctx, richeseAuction: { ...lot, owner: 'unseated' }, sale: { ...ctx.sale!, seller: 'unseated' } },
      { ...ctx, sale: { ...ctx.sale!, seller: null } },
      { ...ctx, sale: { ...ctx.sale!, seller: 'buyer' } },
      { ...ctx, sale: { ...ctx.sale!, amount: 8 } },
      { ...ctx, sale: { ...ctx.sale!, free: true } },
      { ...ctx, sale: { ...ctx.sale!, origin: 'normal', seller: null } },
      { ...ctx, sale: null },
      { ...ctx, auction: context().auction },
      { ...ctx, expansions: [] },
      { ...ctx, richese: false },
      ...(origin === 'blackMarket' ? [{ ...ctx, advanced: false }] : []),
    ];
    for (const invalid of variants) {
      assert.throws(() => source(invalid), IxianReplacementError);
      assert.throws(() => validateIxianReplacementSource(invalid, original, parent), IxianReplacementError);
    }
    // Another canonical card already in the hand cannot replace the actual lot.
    const swapped = { ...ctx, richeseAuction: { ...lot, cardId: older.id } };
    assert.throws(() => validateIxianReplacementSource(swapped, original, parent), IxianReplacementError);
    const absent = {
      ...ctx, players: [{ ...ctx.players[0], hand: [older] }, ctx.players[1]],
    };
    assert.throws(() => source(absent), IxianReplacementError);
    const duplicate = {
      ...ctx, players: [{ ...ctx.players[0], hand: [...ctx.players[0].hand, original.card] }, ctx.players[1]],
    };
    assert.throws(() => source(duplicate), IxianReplacementError);
  }
});

void test('normal purchases preserve their actual nonzero lot index and saved continuation', () => {
  const ctx = context();
  ctx.auction = { ...ctx.auction!, cards: [unsold, purchased], index: 1 };
  const original = createIxianReplacementSource(
    ctx, ixianReplacementEvent(ctx.turn, 'buyer', ctx.sequence, 1), parent,
  );
  assert.equal(original.auctionIndex, 1);
  validateIxianReplacementSource(ctx, JSON.parse(JSON.stringify(original)), parent);
  const closed = closeIxianReplacementSource(original, 'pass', null, initialIxianReplacementCursor());
  validateIxianReplacementHistory(JSON.parse(JSON.stringify([closed.receipt])), closed.cursor);
});

void test('retained purchases keep saved receipt history linear through the game horizon', () => {
  const physical = baseDeck();
  const history: IxianReplacementReceipt[] = [];
  let cursor = initialIxianReplacementCursor();
  for (let turn = 2; turn <= 10; turn++) {
    const ctx = context();
    ctx.turn = turn;
    ctx.sequence = cursor.sequence;
    ctx.auction!.cards = [purchased, top, unsold];
    ctx.players = [...ctx.players, { id: 'guild', hand: [], handLimit: 4 }];
    ctx.physicalCards = physical;
    const original = createIxianReplacementSource(ctx,
      ixianReplacementEvent(turn, 'buyer', cursor.sequence, 0), JSON.stringify(ctx));
    const closed = closeIxianReplacementSource(original, 'pass', null, cursor);
    cursor = closed.cursor;
    history.push(closed.receipt);
    validateIxianReplacementHistory(history, cursor, physical);
  }
  const firstBytes = JSON.stringify(history[0]).length;
  assert.ok(JSON.stringify(history.at(-1)).length <= firstBytes * 2,
    'a receipt must not embed recursively escaped predecessor receipts');
  assert.ok(JSON.stringify(history).length <= history.length * firstBytes * 2,
    'persisted history must grow with purchases, not exponentially');
});

void test('a live purchase cannot target another held card or a card no longer held by its buyer', () => {
  const original = source();
  const missing = context();
  missing.players = missing.players.map(player => player.id === 'buyer'
    ? { ...player, hand: [{ ...older }] }
    : { ...player, hand: [{ ...purchased }] });
  assert.throws(() => validateIxianReplacementSource(missing, original, parent), IxianReplacementError);
  const substituted = { ...original, card: { ...older } };
  assert.throws(() => validateIxianReplacementSource(context(), substituted, parent), IxianReplacementError);
});

void test('canonical descriptors cannot be redefined by a matching auction row and hand', () => {
  for (const patch of [
    { name: 'Another face' }, { kind: 'special' }, { effect: 'fabricated' },
    { id: 'nonphysical-card' }, { extra: 'not-a-card-field' },
  ]) {
    const ctx = context();
    const corrupt = { ...purchased, ...patch } as Card;
    ctx.auction!.cards = [corrupt, unsold];
    ctx.players = [{ ...ctx.players[0], hand: [older, corrupt] }, ctx.players[1]];
    ctx.physicalCards = [older, corrupt, top, unsold];
    assert.throws(() => source(ctx), IxianReplacementError);
  }
});

void test('selected CHOAM retains all original 35 faces alongside separate native Richese custody', () => {
  const deck = treacheryDeck(['choam']);
  const cache = richeseCards();
  assert.equal(deck.length, 35);
  assert.equal(cache.length, 10);
  assert.deepEqual(choamDeck().map(card => card.id).sort(), ['ix-artillery', 'ix-poison-tooth']);
  for (const card of deck) {
    const ctx = purchaseContext(card, ['choam'], true);
    ctx.physicalCards = [...deck, ...cache];
    assert.deepEqual(source(ctx).card, card);
  }
});

void test('base and Ix families remain selected by actual membership, including shared CHOAM identities', () => {
  for (const card of baseDeck()) {
    assert.deepEqual(source(purchaseContext(card, [])).card, card);
    assert.deepEqual(source(purchaseContext(card, ['choam'])).card, card);
  }
  const shared = choamDeck();
  for (const card of ixDeck()) {
    assert.deepEqual(source(purchaseContext(card, ['ix'])).card, card);
    assert.deepEqual(source(purchaseContext(card, ['ix', 'choam'])).card, card);
    assert.throws(() => source(purchaseContext(card, [])), IxianReplacementError);
    const choamOnly = purchaseContext(card, ['choam']);
    if (shared.some(member => member.id === card.id))
      assert.deepEqual(source(choamOnly).card, card);
    else
      assert.throws(() => source(choamOnly), IxianReplacementError);
  }
});

void test('every original cache face requires both selected CHOAM and native Richese even after normal recycling', () => {
  for (const card of richeseCards()) {
    const ctx = purchaseContext(card, ['choam'], true);
    assert.deepEqual(source(ctx).card, card);
    for (const expansions of [[], ['ix'], ['choam'], ['ix', 'choam']]) {
      for (const richese of [false, true]) {
        if (expansions.includes('choam') && richese) continue;
        assert.throws(() => source(purchaseContext(card, expansions, richese)), IxianReplacementError);
      }
    }
    for (const origin of ['cache', 'blackMarket'] as const) {
      const special = purchaseContext(card, ['choam'], true);
      special.sale = { ...special.sale!, origin };
      assert.throws(() => source(special), IxianReplacementError);
    }
  }
});

void test('an ordinary purchase cannot hide unsupported card families elsewhere in live custody', () => {
  for (const card of [...ixDeck(), ...richeseCards()]) {
    const ctx = context();
    ctx.physicalCards = [...ctx.physicalCards, card];
    assert.throws(() => source(ctx), IxianReplacementError);
  }
  for (const card of richeseCards()) {
    for (const [expansions, richese] of [
      [['choam'], false], [['ix'], true], [[], true],
    ] as const) {
      const ctx = context();
      ctx.expansions = expansions;
      ctx.richese = richese;
      ctx.players = [ctx.players[0], { ...ctx.players[1], hand: [card] }];
      ctx.physicalCards = [...ctx.physicalCards, card];
      assert.throws(() => source(ctx), IxianReplacementError);
    }
  }
});

void test('CHOAM and cache faces reject altered descriptors even with matching row, hand and custody', () => {
  for (const card of [...treacheryDeck(['choam']), ...richeseCards()]) {
    const altered: Card[] = [
      { ...card, name: `${card.name} altered` },
      { ...card, kind: card.kind === 'special' ? 'projectile' : 'special' },
      { ...card, effect: 'fabricated' },
      { ...card, id: `${card.id}-copy` },
      { ...card, extra: true } as Card,
    ];
    if (card.effect !== undefined) {
      const missingEffect = { ...card };
      delete missingEffect.effect;
      altered.push(missingEffect);
    }
    for (const corrupt of altered)
      assert.throws(() => source(purchaseContext(corrupt, ['choam'], true)), IxianReplacementError);
  }
});

void test('historical receipts admit the full canonical union without weakening live family gates', () => {
  const [shared] = choamDeck();
  const [cache] = richeseCards();
  const original = source(purchaseContext(shared, ['choam'], true));
  const first = closeIxianReplacementSource(original, 'use', cache, initialIxianReplacementCursor());
  const later = purchaseContext(cache, ['choam'], true);
  later.turn = 2;
  later.sequence = first.cursor.sequence;
  const cacheSource = source(later);
  const second = closeIxianReplacementSource(cacheSource, 'use', cache, first.cursor);
  const history = JSON.parse(JSON.stringify([first.receipt, second.receipt]));
  validateIxianReplacementHistory(history, second.cursor, [...treacheryDeck(['ix']), ...richeseCards()]);
  assert.equal(second.receipt.replacement?.id, cacheSource.card.id);
  assert.throws(() => validateIxianReplacementSource(
    { ...later, richese: false }, cacheSource, parent,
  ), IxianReplacementError);
  assert.throws(() => validateIxianReplacementHistory(history, second.cursor, [
    ...treacheryDeck(['ix']), ...richeseCards(), { ...cache },
  ]), IxianReplacementError);
});

void test('duplicate physical cards reject even when the purchased hand itself looks legal', () => {
  for (const duplicate of [purchased, older, top, unsold]) {
    const ctx = context();
    ctx.physicalCards = [...ctx.physicalCards, { ...duplicate }];
    assert.throws(() => source(ctx), IxianReplacementError);
  }
  const anotherHolder = context();
  anotherHolder.players = [anotherHolder.players[0], {
    ...anotherHolder.players[1], hand: [{ ...purchased }],
  }];
  assert.throws(() => source(anotherHolder), IxianReplacementError);
});

void test('a legal full hand permits net-zero replacement but an already over-cap hand does not', () => {
  const full = context();
  full.players = [{ ...full.players[0], handLimit: 2 }, full.players[1]];
  const original = source(full);
  const before = structuredClone(full);
  const result = closeIxianReplacementSource(original, 'use', top, initialIxianReplacementCursor());
  assert.equal(result.receipt.source.card.id, purchased.id);
  assert.equal(result.receipt.replacement?.id, top.id);
  assert.deepEqual(full, before);
  const overCap = { ...full, players: [{ ...full.players[0], handLimit: 1 }, full.players[1]] };
  assert.throws(() => source(overCap), IxianReplacementError);
});

void test('paid and printed Karama sources retain their native amount without recalculating payment', () => {
  const paid = source();
  assert.equal(paid.amount, 4);
  assert.equal(paid.free, false);
  for (const bid of [0, 4]) {
    const karama = context();
    karama.auction = { ...karama.auction!, bid };
    karama.sale = { ...karama.sale!, amount: bid, free: true };
    const receipt = source(karama);
    assert.equal(receipt.amount, bid);
    assert.equal(receipt.free, true);
  }
  const unpaid = context();
  unpaid.auction = { ...unpaid.auction!, bid: 0 };
  unpaid.sale = { ...unpaid.sale!, amount: 0 };
  assert.throws(() => source(unpaid), IxianReplacementError);
});

void test('current source must preserve normal origin, bidder, lot, price, payment kind, parent and cursor', () => {
  const original = source();
  const variants: IxianReplacementContext[] = [
    { ...context(), status: 'finished' },
    { ...context(), phase: 4 },
    { ...context(), turn: 2 },
    { ...context(), sequence: 1 },
    { ...context(), auction: null },
    { ...context(), sale: null },
    { ...context(), auction: { ...context().auction!, bidder: 'rival' } },
    { ...context(), auction: { ...context().auction!, index: 1 } },
    { ...context(), auction: { ...context().auction!, bid: 5 } },
    { ...context(), sale: { ...context().sale!, winner: 'rival' } },
    { ...context(), sale: { ...context().sale!, amount: 5 } },
    { ...context(), sale: { ...context().sale!, free: true } },
    { ...context(), sale: { ...context().sale!, origin: 'cache' } },
    { ...context(), sale: { ...context().sale!, origin: 'blackMarket' } },
    { ...context(), sale: { ...context().sale!, seller: 'rival' } },
  ];
  for (const ctx of variants)
    assert.throws(() => validateIxianReplacementSource(ctx, original, parent), IxianReplacementError);
  assert.throws(() => validateIxianReplacementSource(context(), original, 'changed-parent'), IxianReplacementError);
  assert.throws(() => createIxianReplacementSource(context(), 'stale-event', parent), IxianReplacementError);
});

void test('an empty deck permits newly discarded purchased card redraw; unsold row is not duplicate custody', () => {
  const ctx = context();
  // The physical census has only hands and the separate unsold row: no draw deck.
  ctx.physicalCards = [older, purchased, unsold];
  const original = source(ctx);
  const result = closeIxianReplacementSource(original, 'use', purchased, initialIxianReplacementCursor());
  assert.equal(result.receipt.replacement?.id, purchased.id);
  validateIxianReplacementHistory([result.receipt], result.cursor, [older, purchased, unsold]);
  // Counting the delivered row alias again is a real custody error.
  assert.throws(() => source({ ...ctx, physicalCards: [...ctx.physicalCards, purchased] }), IxianReplacementError);
});

void test('pass closes without a draw, and neither pass nor use can reuse an already closed cursor', () => {
  const original = source();
  const passed = closeIxianReplacementSource(original, 'pass', null, initialIxianReplacementCursor());
  validateIxianReplacementHistory([passed.receipt], passed.cursor);
  assert.throws(() => closeIxianReplacementSource(original, 'use', top, passed.cursor), IxianReplacementError);
  assert.throws(() => closeIxianReplacementSource(original, 'pass', null, passed.cursor), IxianReplacementError);
  assert.throws(() => closeIxianReplacementSource(original, 'pass', top, initialIxianReplacementCursor()), IxianReplacementError);
  assert.throws(() => closeIxianReplacementSource(original, 'use', null, initialIxianReplacementCursor()), IxianReplacementError);
  assert.throws(() => closeIxianReplacementSource(original, 'use', { ...top, name: 'wrong' }, initialIxianReplacementCursor()), IxianReplacementError);
});

void test('closed receipts survive JSON reload, transfer and a later purchase of the same recycled physical card', () => {
  const first = closeIxianReplacementSource(source(), 'use', top, initialIxianReplacementCursor());
  const later = context();
  later.turn = 2;
  later.sequence = first.cursor.sequence;
  const second = closeIxianReplacementSource(source(later), 'pass', null, first.cursor);
  const history = JSON.parse(JSON.stringify([first.receipt, second.receipt]));
  const cursor = JSON.parse(JSON.stringify(second.cursor));
  // Historical purchased and drawn cards can now be anywhere in the live census.
  validateIxianReplacementHistory(history, cursor, [top, unsold, purchased, older]);
  assert.equal(history[0].source.card.id, history[1].source.card.id);
  assert.notEqual(history[0].source.event, history[1].source.event);
});

void test('history removal, reordering, altered source/outcome and a changed independent cursor reject', () => {
  const first = closeIxianReplacementSource(source(), 'use', top, initialIxianReplacementCursor());
  const ctx = context();
  ctx.turn = 2;
  ctx.sequence = 1;
  const second = closeIxianReplacementSource(source(ctx), 'pass', null, first.cursor);
  const history = [first.receipt, second.receipt];
  const invalid: IxianReplacementReceipt[][] = [
    [], [first.receipt], [second.receipt, first.receipt], [first.receipt, first.receipt],
    [first.receipt, { ...second.receipt, previous: 'unrelated-chain' }],
    [first.receipt, { ...second.receipt, source: { ...second.receipt.source, amount: 7 } }],
    [first.receipt, { ...second.receipt, replacement: top }],
    [{ ...first.receipt, replacement: older }, second.receipt],
  ];
  for (const records of invalid)
    assert.throws(() => validateIxianReplacementHistory(records, second.cursor), IxianReplacementError);
  assert.throws(() => validateIxianReplacementHistory(history, { ...second.cursor, signature: 'changed-head' }), IxianReplacementError);
  assert.throws(() => validateIxianReplacementHistory(history, { ...second.cursor, sequence: 1 }), IxianReplacementError);
  assert.throws(() => validateIxianReplacementHistory(history, initialIxianReplacementCursor()), IxianReplacementError);
});

void test('receipt snapshots cannot be mutated through original source or native draw references', () => {
  const ctx = context();
  const before = structuredClone(ctx);
  const original = source(ctx);
  const drawn = { ...top };
  const result = closeIxianReplacementSource(original, 'use', drawn, initialIxianReplacementCursor());
  assert.deepEqual(ctx, before);
  original.card.name = 'mutated original source reference';
  drawn.name = 'mutated native draw reference';
  assert.equal(result.receipt.source.card.name, purchased.name);
  assert.equal(result.receipt.replacement?.name, top.name);
  validateIxianReplacementHistory([result.receipt], result.cursor);
});

void test('unknown saved receipt fields and malformed canonical custody fail closed', () => {
  const original = source();
  assert.throws(() => validateIxianReplacementSource(context(), { ...original, extra: true } as never, parent), IxianReplacementError);
  assert.throws(() => validateIxianReplacementSource(context(), null as never, parent), IxianReplacementError);
  const result = closeIxianReplacementSource(original, 'pass', null, initialIxianReplacementCursor());
  assert.throws(() => validateIxianReplacementHistory([{ ...result.receipt, extra: true } as never], result.cursor), IxianReplacementError);
  assert.throws(() => validateIxianReplacementHistory([result.receipt], { ...result.cursor, extra: true } as never), IxianReplacementError);
  assert.throws(() => validateIxianReplacementHistory([result.receipt], result.cursor, [{ ...purchased, effect: 'forged' }]), IxianReplacementError);
});