/**
 * T84 — Playwright e2e for `religious_conversion` + `kamikaze` parity rules.
 *
 * Both descriptors use trigger-rooted cascades that the existing
 * `__test__.activate-descriptor` lifter (T79) cannot drive — that lifter
 * requires `on-rule-activated` as the descriptor root so the inner arm
 * surfaces as a registerable top-level primitive list. religious_conversion
 * uses `on-move`, kamikaze uses `on-capture` — both seed per-piece hook
 * facts (OnMoveHooks / OnCaptureHooks) at apply-time and only fire when
 * the engine's onAfterMove dispatcher reaches `fireOn*Hooks` for the
 * moving / capturing piece.
 *
 * Driving the cascade end-to-end therefore requires a SECOND test-debug
 * frame that:
 *   1. Wipes the FIDE starting position.
 *   2. Places a deterministic minimal set of pieces.
 *   3. Seeds the descriptor's INNER arm directly onto the relevant
 *      piece's hook fact (mirrors what `applyCustomDescriptor` would
 *      produce on a fixed dispatcher — see religious_conversion-real.test.ts
 *      and kamikaze-real.test.ts § "seeding On{Move,Capture}Hooks").
 *   4. Optionally pins `RngSeed` for descriptors with `with-probability`
 *      (kamikaze).
 *   5. Broadcasts a fresh `game.state` so the client renders the
 *      synthetic board.
 *
 * That frame is `__test__.setup-board` (T84, packages/server/src/broadcast.ts).
 *
 * ─────────────────────────────────────────────────────────────────────
 * Test 1 — religious_conversion (on-move + for-each-adjacent + set-piece-attr)
 * ─────────────────────────────────────────────────────────────────────
 *
 * Setup (after clear-board, kings preserved at e1/e8):
 *   - white bishop at d4   (will move to b6, the on-move hook target)
 *   - white pawn at a6     (adjacent to b6 destination — already white,
 *                           Color set is a no-op, pin: ally unchanged)
 *   - black pawns at a7, b7, c7 (adjacent to b6 destination — should
 *                           flip to white after the move)
 *
 * The bishop's path d4→c5→b6 is along an empty diagonal (c5 is the
 * only square traversed; cleared). After applyMove(d4→b6) fires
 * fireOnMoveHooks(bishop), the inner arm (for-each-adjacent target=self,
 * filter={occupied:true, excludeKing:true}, then=set-piece-attr Color)
 * walks the 8 squares around b6 and flips the Color of every adjacent
 * non-king piece to the bishop's Color (white).
 *
 * Pin:
 *   - a7/b7/c7 render `data-piece="white-pawn"` (was black).
 *   - a6 stays `data-piece="white-pawn"` (ally — Color set was a no-op).
 *   - bishop at b6.
 *
 * ─────────────────────────────────────────────────────────────────────
 * Test 2 — kamikaze (on-capture + with-probability + for-each-adjacent + destroy-piece)
 * ─────────────────────────────────────────────────────────────────────
 *
 * The on-disk fixture has `p: 0.25`. Driving an e2e against that
 * stochastic branch is brittle — the first applyMove may or may not
 * consume earlier RNG draws (the integration preset's onAfterMove
 * runs preset hooks BEFORE fireOnCaptureHooks, and any preset that
 * calls `engine.rng().next()` shifts the with-probability draw's
 * stream offset). Instead we use the task-suggested workaround:
 * a per-test descriptor variant with `p: 1.0` so AOE fires
 * deterministically on every capture. The kamikaze-real.test.ts
 * locked-numerics test (seed=42 → 32 hits at exact stream offsets) is
 * what pins the stochastic contract; this e2e pins the WIRE / UI /
 * dispatcher path — same cascade, deterministic outcome.
 *
 * Setup (after clear-board with kings retracted, then re-placed by us):
 *   - white queen at e2          (will capture the e4 pawn)
 *   - black pawn at e4           (the capture target)
 *   - black pawns at d4, f4      (adjacent to e4 destination — AOE victims)
 *   - black king at e5           (adjacent to e4 destination — IMMUNE)
 *   - white king at e1, black king at e8 (re-placed for legality of the
 *                                 game state — checking against d4/f4 etc
 *                                 doesn't matter for hook-firing)
 *
 * Queen path e2→e3→e4 (e3 is empty post-clear). The capture fires
 * fireOnCaptureHooks(queen) — the inner arm:
 *   with-probability(p=1.0) → for-each-adjacent(filter excludeKing) → destroy-piece
 * always enters the for-each branch, walks {d3,e3,f3,d4,f4,d5,e5,f5},
 * narrows by occupied + excludeKing → matches d4 (black pawn), f4
 * (black pawn). e5 is a king → IMMUNE. destroy-piece retracts every
 * piece-identity fact for d4 + f4.
 *
 * Pins:
 *   - queen at e4 (capture succeeded; e4 black pawn gone).
 *   - d4 + f4 squares render no piece (AOE destroyed them).
 *   - e5 black king STILL renders `data-piece="black-king"`
 *     (king-immunity invariant from kamikaze.test.ts § "king never
 *     destroyed").
 *
 * ─────────────────────────────────────────────────────────────────────
 * Why we don't extend `parity-rules.spec.ts`
 * ─────────────────────────────────────────────────────────────────────
 *
 * Per the T84 brief: T83 owns parity-rules (parry, all_on_red,
 * ice_physics). Keeping religious + kamikaze in a sibling spec file
 * avoids merge conflicts on the shared describe-block scaffolding and
 * lets each spec own its own server fixture lifecycle.
 */

import { test, expect, type Page } from '@playwright/test';
import { spawn, type ChildProcess } from 'node:child_process';
import { setTimeout as sleep } from 'node:timers/promises';
import { existsSync, mkdirSync, readFileSync } from 'node:fs';
import { join } from 'node:path';

// ---------------------------------------------------------------------------
// Server lifecycle (mirrors `multiplayer.spec.ts` / `request-choice.spec.ts`)
// ---------------------------------------------------------------------------

let wsServerProcess: ChildProcess | null = null;

async function isWsServerRunning(): Promise<boolean> {
  try {
    const res = await fetch('http://localhost:7357/healthz');
    return res.ok;
  } catch {
    return false;
  }
}

test.beforeAll(async () => {
  if (await isWsServerRunning()) return;
  wsServerProcess = spawn('bun', ['run', 'packages/server/src/index.ts'], {
    stdio: 'pipe',
    env: { ...process.env, PORT: '7357' },
  });
  for (let i = 0; i < 40; i++) {
    await sleep(250);
    if (await isWsServerRunning()) break;
  }
});

test.afterAll(async () => {
  if (wsServerProcess) {
    wsServerProcess.kill('SIGINT');
    await sleep(200);
    wsServerProcess = null;
  }
});

// ---------------------------------------------------------------------------
// Fixtures + screenshot helpers
// ---------------------------------------------------------------------------

const EVIDENCE_DIR = join(process.cwd(), '.sisyphus/evidence/wave15-t84-screenshots');
if (!existsSync(EVIDENCE_DIR)) mkdirSync(EVIDENCE_DIR, { recursive: true });

const RELIGIOUS_CONVERSION_DESCRIPTOR = JSON.parse(
  readFileSync(
    join(process.cwd(), 'packages/chess/src/__fixtures__/parity/religious_conversion.json'),
    'utf8',
  ),
) as Record<string, unknown>;

const KAMIKAZE_DESCRIPTOR = JSON.parse(
  readFileSync(
    join(process.cwd(), 'packages/chess/src/__fixtures__/parity/kamikaze.json'),
    'utf8',
  ),
) as Record<string, unknown>;

/**
 * Build a per-test variant of the kamikaze descriptor where
 * with-probability's `p` is forced to 1.0. This is the
 * "always-fires" variant the T84 brief flags as the simpler path
 * compared to brittle seed-fishing for a "first draw < 0.25" RNG
 * vector. The original 0.25 contract is pinned by
 * kamikaze.test.ts (locked-stream-offsets) — we don't need to
 * reproduce its statistical outcome here.
 */
function kamikazeAlwaysFires(): Record<string, unknown> {
  const cloned = JSON.parse(JSON.stringify(KAMIKAZE_DESCRIPTOR)) as {
    id: string;
    primitives: Array<{
      kind: string;
      params: { primitives: Array<{ kind: string; params: { p: number } }> };
    }>;
  };
  // Walk on-capture → with-probability and patch p in place.
  const onCapture = cloned.primitives[0]!;
  const withProb = onCapture.params.primitives[0]!;
  if (withProb.kind !== 'with-probability') {
    throw new Error(
      `parity fixture drift: expected on-capture > with-probability, got ${withProb.kind}`,
    );
  }
  withProb.params.p = 1.0;
  // Use a distinct id so registry entries don't collide with the
  // canonical id. Brand-coercion is the same `asCustomModifierId`
  // path the server uses internally.
  cloned.id = 'parity:kamikaze__test-p1';
  return cloned as unknown as Record<string, unknown>;
}

async function snapshot(page: Page, label: string): Promise<void> {
  await page.screenshot({
    path: join(EVIDENCE_DIR, `${label}.png`),
    fullPage: true,
  });
}

// ---------------------------------------------------------------------------
// Room helpers (raw WS — no Lobby UI involvement)
// ---------------------------------------------------------------------------

async function wsCreateRoom(
  page: Page,
): Promise<{ code: string; token: string; color: string }> {
  return page.evaluate(async () => {
    return new Promise<{ code: string; token: string; color: string }>(
      (resolve, reject) => {
        const ws = new WebSocket('ws://localhost:7357/ws');
        const timer = setTimeout(
          () => reject(new Error('wsCreateRoom: timeout')),
          5000,
        );
        ws.onopen = () => {
          ws.send(
            JSON.stringify({
              v: 1,
              seq: 1,
              ts: Date.now(),
              type: 'room.create',
              payload: {},
            }),
          );
        };
        ws.onmessage = (e: MessageEvent) => {
          const msg = JSON.parse(e.data as string) as {
            type: string;
            payload: {
              code: string;
              token: string;
              color: string;
              message?: string;
            };
          };
          if (msg.type === 'room.created') {
            clearTimeout(timer);
            ws.close();
            resolve(msg.payload);
          } else if (msg.type === 'error') {
            clearTimeout(timer);
            ws.close();
            reject(new Error(msg.payload.message ?? 'room.create error'));
          }
        };
        ws.onerror = () => {
          clearTimeout(timer);
          reject(new Error('wsCreateRoom: WebSocket error'));
        };
      },
    );
  });
}

async function joinAsHost(
  page: Page,
): Promise<{ code: string; token: string; color: string }> {
  await page.goto('http://localhost:5173/');
  await page.waitForSelector('[data-testid="page-home"]');
  const room = await wsCreateRoom(page);
  await page.evaluate((r) => {
    sessionStorage.setItem('room-code', r.code);
    sessionStorage.setItem('room-token', r.token);
    sessionStorage.setItem('player-color', r.color);
  }, room);
  await page.goto('http://localhost:5173/game');
  await expect(page.locator('[data-testid="turn-indicator"]')).toBeVisible();
  // Wait for the GameClient to install on window — the setup-board frame
  // travels through it.
  await page.waitForFunction(
    () =>
      Boolean(
        (globalThis as { __paratypeChessClient?: unknown })
          .__paratypeChessClient,
      ),
    null,
    { timeout: 5000 },
  );
  return room;
}

// ---------------------------------------------------------------------------
// `__test__.setup-board` driver
// ---------------------------------------------------------------------------

interface BoardPlacement {
  square: string | number;
  type: 'pawn' | 'knight' | 'bishop' | 'rook' | 'queen' | 'king';
  color: 'white' | 'black';
  hasMoved?: boolean;
  handle?: string;
}

interface BoardHookSpec {
  pieceHandle?: string;
  pieceSquare?: string | number;
  hookAttr:
    | 'OnMoveHooks'
    | 'OnCaptureHooks'
    | 'OnCapturedHooks'
    | 'OnDamagedHooks'
    | 'OnPromotionHooks'
    | 'OnTurnStartHooks'
    | 'OnTurnEndHooks'
    | 'OnCheckReceivedHooks'
    | 'OnCheckDeliveredHooks'
    | 'OnMovedOntoSquareHooks';
  descriptor: unknown;
  descriptorIdOverride?: string;
}

interface BoardSetupArgs {
  code: string;
  clear?: boolean;
  clearIncludingKings?: boolean;
  placements?: BoardPlacement[];
  rngSeed?: number;
  hooks?: BoardHookSpec[];
  turn?: 'white' | 'black';
}

/**
 * Send `__test__.setup-board` through the page's existing GameClient
 * socket. The handler runs server-side, mutates the engine, and emits
 * a fresh `game.state` snapshot — so the page's own MultiplayerGame
 * view re-renders the synthetic board automatically. The handle→id
 * echo (`__test__.board-ready`) is intentionally a no-op at the
 * client layer (the GameClient's `dispatchServerMessage` ignores
 * unknown types for forward-compat) — DOM-level assertions are what
 * the e2e relies on for verification.
 */
async function setupBoard(page: Page, args: BoardSetupArgs): Promise<void> {
  await page.evaluate(async (a) => {
    type Client = {
      send: (msg: { type: string; payload: unknown }) => void;
      readonly isConnected?: boolean;
    };
    const getClient = (): Client | undefined =>
      (globalThis as { __paratypeChessClient?: Client }).__paratypeChessClient;
    const deadline = Date.now() + 3000;
    let client = getClient();
    // Wait for an OPEN GameClient socket. `isConnected` is a getter
    // (NOT a function) — invoke as a property read. The
    // `__paratypeChessClient` reference itself can ALSO churn during
    // React StrictMode unmount→remount, so re-fetch every poll.
    while (Date.now() < deadline) {
      client = getClient();
      if (client && client.isConnected === true) break;
      await new Promise((r) => setTimeout(r, 50));
    }
    if (!client || client.isConnected !== true) {
      throw new Error('setupBoard: GameClient never became connected');
    }
    client.send({
      type: '__test__.setup-board',
      payload: {
        roomCode: a.code,
        clear: a.clear,
        clearIncludingKings: a.clearIncludingKings,
        placements: a.placements,
        rngSeed: a.rngSeed,
        hooks: a.hooks,
        turn: a.turn,
      },
    });
  }, args);
}

/**
 * Send `game.move` straight through the page's existing GameClient
 * socket. The drag-based UI path used by `multiplayer.spec.ts` works
 * fine when the engine state is the FIDE starting position (which
 * is what the prediction layer's BaseEngine matches at mount time),
 * but on a synthetic board produced via `__test__.setup-board` the
 * prediction-layer's getAllLegalMoves can disagree with the
 * server-side engine on edge cases (e.g. a bishop spawned without
 * the integration preset's spawn hooks may carry default
 * `OnMoveHooks` that the prediction's WeakMap-keyed onBeforeMove
 * snapshot doesn't recognise as the same identity). Going around
 * the prediction layer eliminates that variability — the test
 * exercises the SERVER's applyMove + fireOnMoveHooks pipeline,
 * which is the actual contract under test.
 */
async function sendMove(
  page: Page,
  from: string,
  to: string,
): Promise<void> {
  // Poll: GameClient.send is a NO-OP when the underlying WebSocket
  // isn't OPEN ("Messages sent while the socket is not OPEN are
  // silently dropped" — client.ts § send). React StrictMode +
  // reconnect on `/game` mount can leave a ~200ms window where
  // `__paratypeChessClient` is fresh but the socket is still
  // connecting. Poll `isConnected` (a GETTER, not a function) until
  // OPEN, then send.
  await page.evaluate(
    async (a) => {
      type Client = {
        send: (msg: { type: string; payload: unknown }) => void;
        sendMove?: (from: string, to: string) => void;
        readonly isConnected?: boolean;
      };
      const getClient = (): Client | undefined =>
        (globalThis as { __paratypeChessClient?: Client }).__paratypeChessClient;
      const deadline = Date.now() + 3000;
      let client = getClient();
      while (Date.now() < deadline) {
        client = getClient();
        if (client && client.isConnected === true) break;
        await new Promise((r) => setTimeout(r, 50));
      }
      if (!client || client.isConnected !== true) {
        throw new Error('sendMove: GameClient never became connected');
      }
      if (typeof client.sendMove === 'function') {
        client.sendMove(a.from, a.to);
        return;
      }
      client.send({
        type: 'game.move',
        payload: { from: a.from, to: a.to },
      });
    },
    { from, to },
  );
}

// ---------------------------------------------------------------------------
// Test 1 — religious_conversion (on-move → for-each-adjacent → set-piece-attr)
// ---------------------------------------------------------------------------

test('T84/religious_conversion: bishop move converts adjacent enemy non-king pieces to its color', async ({
  browser,
}) => {
  const ctx = await browser.newContext();
  const page = await ctx.newPage();
  const room = await joinAsHost(page);
  expect(room.color).toBe('white');

  // Configure the synthetic board. Kings preserve their FIDE
  // starting positions (e1 / e8); we add our own minimal piece set
  // around the bishop's destination square b6. Server's setup-board
  // handler emits a fresh `game.state` after applying the placement
  // set; the client's existing snapshot subscription re-renders the
  // board, so we don't need to wait for an explicit ack.
  await setupBoard(page, {
    code: room.code,
    clear: true,
    clearIncludingKings: false,
    turn: 'white',
    placements: [
      { square: 'd4', type: 'bishop', color: 'white', handle: 'bishop' },
      { square: 'a6', type: 'pawn', color: 'white', handle: 'allyA6' },
      { square: 'a7', type: 'pawn', color: 'black', handle: 'enemyA7' },
      { square: 'b7', type: 'pawn', color: 'black', handle: 'enemyB7' },
      { square: 'c7', type: 'pawn', color: 'black', handle: 'enemyC7' },
    ],
    hooks: [
      {
        pieceHandle: 'bishop',
        hookAttr: 'OnMoveHooks',
        descriptor: RELIGIOUS_CONVERSION_DESCRIPTOR,
      },
    ],
  });

  // Wait for the snapshot broadcast to land — the bishop should
  // appear at d4 (its starting FIDE square is c1/f1, so a fresh
  // d4 placement confirms the broadcast hit).
  await expect(
    page.locator('[data-square="d4"] [data-piece="white-bishop"]'),
  ).toBeVisible({ timeout: 5000 });
  await expect(
    page.locator('[data-square="a7"] [data-piece="black-pawn"]'),
  ).toBeVisible();
  await expect(
    page.locator('[data-square="b7"] [data-piece="black-pawn"]'),
  ).toBeVisible();
  await expect(
    page.locator('[data-square="c7"] [data-piece="black-pawn"]'),
  ).toBeVisible();
  await snapshot(page, 'religious-pre-move');

  // Drive the move via the GameClient's `game.move` send (skipping
  // the prediction layer — see `sendMove` rationale). The server's
  // applyMove fires fireOnMoveHooks, which walks the seeded arm,
  // and broadcasts the resulting game.delta / game.state.
  await sendMove(page, 'd4', 'b6');

  // Bishop landed.
  await expect(
    page.locator('[data-square="b6"] [data-piece="white-bishop"]'),
  ).toBeVisible({ timeout: 5000 });

  // Black pawns adjacent to b6 (a7, b7, c7) are NOW white.
  await expect(
    page.locator('[data-square="a7"] [data-piece="white-pawn"]'),
  ).toBeVisible({ timeout: 5000 });
  await expect(
    page.locator('[data-square="b7"] [data-piece="white-pawn"]'),
  ).toBeVisible();
  await expect(
    page.locator('[data-square="c7"] [data-piece="white-pawn"]'),
  ).toBeVisible();

  // The white ally at a6 (also adjacent) is unchanged — still a
  // white pawn. The set-piece-attr Color was a no-op for ally
  // squares because the descriptor's value resolver pulls
  // self.Color (white) and the ally was already white.
  await expect(
    page.locator('[data-square="a6"] [data-piece="white-pawn"]'),
  ).toBeVisible();

  // Negative pin: NO black pawns remain on a7/b7/c7.
  await expect(
    page.locator('[data-square="a7"] [data-piece="black-pawn"]'),
  ).toHaveCount(0);
  await expect(
    page.locator('[data-square="b7"] [data-piece="black-pawn"]'),
  ).toHaveCount(0);
  await expect(
    page.locator('[data-square="c7"] [data-piece="black-pawn"]'),
  ).toHaveCount(0);

  await snapshot(page, 'religious-post-conversion');
  await ctx.close();
});

// ---------------------------------------------------------------------------
// Test 2 — kamikaze (on-capture → with-probability → for-each-adjacent → destroy-piece)
// ---------------------------------------------------------------------------

test('T84/kamikaze: capture triggers AOE destroying adjacent non-king pieces; king immune', async ({
  browser,
}) => {
  const ctx = await browser.newContext();
  const page = await ctx.newPage();
  const room = await joinAsHost(page);
  expect(room.color).toBe('white');

  // Setup: full clear (kings retracted too) so we can re-place
  // both kings explicitly — the test's "AOE-victim" set sits next
  // to a black king on e5, and we need a clean board to assert
  // king-immunity without ambiguity from the FIDE starting kings.
  const descriptor = kamikazeAlwaysFires();
  await setupBoard(page, {
    code: room.code,
    clear: true,
    clearIncludingKings: true,
    turn: 'white',
    rngSeed: 42, // fixed; with p=1.0 the draw is moot but pinning the
    //            seed makes the test order-independent w.r.t. unrelated
    //            preset RNG draws on the integration onAfterMove path.
    placements: [
      // Re-place both kings — required for engine legality (in-check
      // detection walks both kings; absent kings throw).
      { square: 'e1', type: 'king', color: 'white', handle: 'wKing' },
      { square: 'h8', type: 'king', color: 'black', handle: 'bKing' },
      // The capturing piece + its target.
      { square: 'e2', type: 'queen', color: 'white', handle: 'queen' },
      { square: 'e4', type: 'pawn', color: 'black', handle: 'target' },
      // AOE victims — adjacent to e4 (the queen's destination).
      { square: 'd4', type: 'pawn', color: 'black', handle: 'aoeD4' },
      { square: 'f4', type: 'pawn', color: 'black', handle: 'aoeF4' },
      // King-immunity test: a SECOND black king adjacent to e4. The
      // descriptor's filter excludes kings unconditionally, so this
      // king must survive the AOE.
      { square: 'e5', type: 'king', color: 'black', handle: 'aoeKing' },
    ],
    hooks: [
      {
        pieceHandle: 'queen',
        hookAttr: 'OnCaptureHooks',
        descriptor,
        descriptorIdOverride: 'parity:kamikaze__test-p1',
      },
    ],
  });

  // Pre-capture board pin.
  await expect(
    page.locator('[data-square="e2"] [data-piece="white-queen"]'),
  ).toBeVisible({ timeout: 5000 });
  await expect(
    page.locator('[data-square="e4"] [data-piece="black-pawn"]'),
  ).toBeVisible();
  await expect(
    page.locator('[data-square="d4"] [data-piece="black-pawn"]'),
  ).toBeVisible();
  await expect(
    page.locator('[data-square="f4"] [data-piece="black-pawn"]'),
  ).toBeVisible();
  await expect(
    page.locator('[data-square="e5"] [data-piece="black-king"]'),
  ).toBeVisible();
  await snapshot(page, 'kamikaze-pre-capture');

  // Drive the capture: queen e2 → e4 (e3 is empty). The server's
  // applyMove fires fireOnCaptureHooks(queen) on the post-move
  // pass; the inner arm enters with-probability(p=1.0) — always
  // fires — walks adjacent squares of the queen's NEW position
  // (e4) with excludeKing+occupied filters, and destroy-piece
  // retracts every matched id.
  await sendMove(page, 'e2', 'e4');

  // Capture succeeded: queen on e4, the target pawn is gone (its
  // Position fact retracted by the standard capture pipeline before
  // the AOE arm runs).
  await expect(
    page.locator('[data-square="e4"] [data-piece="white-queen"]'),
  ).toBeVisible({ timeout: 5000 });

  // AOE victims destroyed — d4 and f4 squares no longer hold a piece
  // (destroy-piece retracts the full piece-identity attribute set).
  await expect(page.locator('[data-square="d4"] [data-piece]')).toHaveCount(
    0,
    { timeout: 5000 },
  );
  await expect(page.locator('[data-square="f4"] [data-piece]')).toHaveCount(0);

  // King immunity — the black king on e5 is STILL there. This is
  // the load-bearing pin from kamikaze.test.ts § "king never
  // destroyed".
  await expect(
    page.locator('[data-square="e5"] [data-piece="black-king"]'),
  ).toBeVisible();

  await snapshot(page, 'kamikaze-post-aoe');
  await ctx.close();
});