import { readFileSync } from 'node:fs';
import assert from 'node:assert/strict';
import { test } from 'node:test';
import type {
  GameEntry,
  GameHost,
  GameModule,
  PlatformGameSnapshot,
  PlatformToGameEvent,
} from '../../YouleNexus/assets/framework/sdk/contracts/index.ts';
import { GameSessionHost } from '../../YouleNexus/assets/framework/sdk/runtime/game-session-host.ts';
import { RuntimeSession } from '../../YouleNexus/assets/framework/platform/runtime-session.ts';
import { PlatformStore } from '../../YouleNexus/assets/framework/platform/stores/platform-store.ts';
import { selectGameSnapshot } from '../../YouleNexus/assets/framework/platform/stores/selectors.ts';

function fixture(name: string): Record<string, unknown> {
  return JSON.parse(readFileSync(new URL(`../fixtures/contracts/${name}`, import.meta.url), 'utf8')).data;
}

function makeSession() {
  const store = new PlatformStore();
  const log: string[] = [];
  const restored: unknown[] = [];
  const events: Array<{ event: PlatformToGameEvent; snapshot: PlatformGameSnapshot }> = [];
  let host: GameHost;
  const entry: GameEntry = {
    key: 'fixture',
    gameId: 41,
    route: 'fixture-game',
    resolveSeatCount: () => 4,
    createModule: (): GameModule => ({
      attach(attachedHost) {
        host = attachedHost;
        attachedHost.getSnapshot();
        log.push('attach');
      },
      handlePlatformEvent(event) {
        events.push({ event, snapshot: host.getSnapshot() });
        log.push(`event:${event.type}`);
      },
      handleGameMessage() {},
      restore(deskinfo) {
        restored.push(deskinfo);
        log.push('restore');
      },
      dispose() { log.push('dispose'); },
    }),
  };
  const gameSession = new GameSessionHost(entry);
  log.length = 0;
  const session = new RuntimeSession({
    store,
    gameSession,
    createGameHostLease: () => ({
      host: {
        seat: { toView: (seat) => seat, toServer: (seat) => seat },
        getSnapshot: () => selectGameSnapshot(store.getState()),
        subscribe: () => () => {},
        sendGameMessage() {},
        execute() {},
      },
      invalidate() {},
    }),
  });
  return { store, gameSession, session, log, restored, events };
}

test('RuntimeSession commits a room login before opening, publishing, and restoring deskinfo', () => {
  const setup = makeSession();
  const data = fixture('player-login-room.json');
  setup.store.subscribe(() => { setup.log.push('store'); });

  setup.session.markLoginPending();
  setup.session.handleLogin(data);

  assert.equal(setup.session.loginPending, false);
  assert.equal(setup.store.getState().room.kind, 'inside');
  assert.equal('deskinfo' in setup.store.getState().room, false);
  assert.equal(setup.restored.length, 1);
  assert.equal(setup.restored[0], data.deskinfo);
  assert.deepEqual(setup.log, ['store', 'attach', 'event:room.entered', 'restore']);
  assert.equal(setup.events[0]?.snapshot.room.roomcode, '100001');
  assert.equal(setup.events[0]?.event.type, 'room.entered');
  if (setup.events[0]?.event.type === 'room.entered') {
    assert.equal(setup.events[0].event.roomtype, setup.events[0].snapshot.room.roomtype);
  }
});

test('RuntimeSession never treats isbattle as a restore signal without truthy deskinfo', () => {
  for (const deskinfo of [undefined, null, false, 0, '']) {
    const setup = makeSession();
    const data = fixture('player-login-room.json');
    if (deskinfo === undefined) delete data.deskinfo;
    else data.deskinfo = deskinfo;
    data.isbattle = 1;

    setup.session.handleLogin(data);

    assert.deepEqual(setup.restored, [], `deskinfo=${String(deskinfo)}`);
    assert.equal(setup.store.getState().room.kind, 'inside');
  }
});

test('RuntimeSession self join commits, opens a fresh session, and restores the same snapshot once', () => {
  const setup = makeSession();
  setup.session.handleLogin(fixture('player-login-success.json'));
  setup.log.length = 0;
  const join = fixture('self-join-room.json');
  setup.store.subscribe(() => { setup.log.push('store'); });

  setup.session.handleSelfJoin(join);

  assert.equal(setup.store.getState().room.kind, 'inside');
  assert.equal(setup.restored.length, 1);
  assert.equal(setup.restored[0], join.deskinfo);
  assert.deepEqual(setup.log, ['store', 'attach', 'event:room.entered', 'restore']);
});

test('RuntimeSession self join honors the parser-owned deskwar and deskinfo matrix', () => {
  const cases = [
    { deskwar: 'missing', deskinfo: false, expectedStage: 0 },
    { deskwar: 0, deskinfo: false, expectedStage: 0 },
    { deskwar: 1, deskinfo: false, expectedStage: 1 },
    { deskwar: 'missing', deskinfo: true, expectedStage: 1 },
    { deskwar: 0, deskinfo: true, expectedStage: 1 },
    { deskwar: 1, deskinfo: true, expectedStage: 1 },
  ] as const;

  for (const row of cases) {
    const setup = makeSession();
    setup.session.handleLogin(fixture('player-login-success.json'));
    const data = fixture('self-join-room.json');
    if (row.deskwar === 'missing') delete data.deskwar;
    else data.deskwar = row.deskwar;
    const deskinfo = { round: 7 };
    if (row.deskinfo) data.deskinfo = deskinfo;
    else delete data.deskinfo;
    data.isbattle = 1;

    setup.session.handleSelfJoin(data);

    const state = setup.store.getState();
    assert.equal(state.room.kind, 'inside');
    if (state.room.kind === 'inside') {
      assert.equal(state.room.stage, row.expectedStage, JSON.stringify(row));
    }
    assert.equal(setup.restored.length, row.deskinfo ? 1 : 0, JSON.stringify(row));
    if (row.deskinfo) assert.equal(setup.restored[0], deskinfo);
  }
});

type LeaseFailurePoint =
  | 'lease-factory'
  | 'module-create'
  | 'attach'
  | 'event'
  | 'restore'
  | 'dispose'
  | 'invalidate';

interface LeaseRecord {
  readonly host: GameHost;
  invalidations: number;
}

function makeLeaseSession() {
  const store = new PlatformStore();
  const leases: LeaseRecord[] = [];
  const attachedHosts: GameHost[] = [];
  const failures = new Set<LeaseFailurePoint>();
  const errors = Object.fromEntries([
    'lease-factory', 'module-create', 'attach', 'event', 'restore', 'dispose', 'invalidate',
  ].map((point) => [point, new Error(`failure:${point}`)])) as Record<LeaseFailurePoint, Error>;
  let validatingEntry = true;
  let moduleDisposals = 0;

  function host(): GameHost {
    return {
      seat: { toView: (seat) => seat, toServer: (seat) => seat },
      getSnapshot: () => selectGameSnapshot(store.getState()),
      subscribe: () => () => {},
      sendGameMessage() {},
      execute() {},
    };
  }

  const entry: GameEntry = {
    key: 'lease-fixture',
    gameId: 41,
    route: 'fixture-game',
    resolveSeatCount: () => 4,
    createModule: (): GameModule => {
      if (!validatingEntry && failures.has('module-create')) throw errors['module-create'];
      return {
        attach(attachedHost) {
          if (!validatingEntry) attachedHosts.push(attachedHost);
          if (!validatingEntry && failures.has('attach')) throw errors.attach;
        },
        handlePlatformEvent() {
          if (!validatingEntry && failures.has('event')) throw errors.event;
        },
        handleGameMessage() {},
        restore() {
          if (!validatingEntry && failures.has('restore')) throw errors.restore;
        },
        dispose() {
          if (validatingEntry) return;
          moduleDisposals += 1;
          if (failures.has('dispose')) throw errors.dispose;
        },
      };
    },
  };
  const gameSession = new GameSessionHost(entry);
  validatingEntry = false;
  const sessionOptions = {
    store,
    gameSession,
    createGameHostLease() {
      if (failures.has('lease-factory')) throw errors['lease-factory'];
      const record: LeaseRecord = { host: host(), invalidations: 0 };
      leases.push(record);
      return {
        host: record.host,
        invalidate() {
          record.invalidations += 1;
          if (failures.has('invalidate')) throw errors.invalidate;
        },
      };
    },
  };
  const session = new RuntimeSession(sessionOptions);
  return {
    store,
    gameSession,
    session,
    leases,
    attachedHosts,
    errors,
    setFailures(...points: LeaseFailurePoint[]) {
      failures.clear();
      for (const point of points) failures.add(point);
    },
    getModuleDisposals: () => moduleDisposals,
  };
}

function caughtError(operation: () => void): Error {
  try {
    operation();
  } catch (error) {
    assert.ok(error instanceof Error);
    return error;
  }
  assert.fail('expected operation to throw');
}

test('RuntimeSession creates a fresh host lease per login/self-join replacement and invalidates on self exit', () => {
  const setup = makeLeaseSession();

  setup.session.handleLogin(fixture('player-login-room.json'));
  setup.session.handleSelfJoin(fixture('self-join-room.json'));
  setup.session.handleLogin(fixture('player-login-room.json'));

  assert.equal(setup.leases.length, 3);
  assert.equal(new Set(setup.attachedHosts).size, 3);
  assert.deepEqual(setup.leases.map((lease) => lease.invalidations), [1, 1, 0]);
  assert.equal(setup.attachedHosts[0], setup.leases[0]?.host);
  assert.equal(setup.attachedHosts[1], setup.leases[1]?.host);
  assert.equal(setup.attachedHosts[2], setup.leases[2]?.host);

  setup.session.handleSelfExit({ raw: {} });

  assert.deepEqual(setup.leases.map((lease) => lease.invalidations), [1, 1, 1]);
  assert.equal(setup.gameSession.state, 'idle');
  assert.equal(setup.session.state, 'operational');
});

test('RuntimeSession invalidates the active lease on a successful server switch', () => {
  const setup = makeLeaseSession();
  setup.session.handleLogin(fixture('player-login-room.json'));

  setup.session.handleServerSwitch(() => {});

  assert.equal(setup.leases[0]?.invalidations, 1);
  assert.equal(setup.gameSession.state, 'idle');
  assert.equal(setup.session.state, 'operational');
});

for (const failure of [
  'lease-factory', 'module-create', 'attach', 'event', 'restore',
] as const) {
  test(`RuntimeSession cleans a failed room open and enters terminal fault at ${failure}`, () => {
    const setup = makeLeaseSession();
    setup.setFailures(failure);

    const error = caughtError(() => setup.session.handleLogin(fixture('player-login-room.json')));

    assert.equal(setup.session.state, 'faulted');
    assert.equal(setup.session.fault, error);
    assert.equal(setup.gameSession.state, 'idle');
    if (failure === 'lease-factory') {
      assert.equal(setup.leases.length, 0);
    } else {
      assert.equal(setup.leases.length, 1);
      assert.equal(setup.leases[0]?.invalidations, 1);
    }
    assert.throws(
      () => setup.session.handleLogin(fixture('player-login-success.json')),
      /fault/i,
    );
  });
}

for (const replacement of ['login', 'self-join'] as const) {
  test(`RuntimeSession invalidates the old lease and faults when ${replacement} replacement disposal fails`, () => {
    const setup = makeLeaseSession();
    setup.session.handleLogin(fixture('player-login-room.json'));
    setup.setFailures('dispose');

    const error = caughtError(() => {
      if (replacement === 'login') setup.session.handleLogin(fixture('player-login-room.json'));
      else setup.session.handleSelfJoin(fixture('self-join-room.json'));
    });

    assert.equal(setup.session.state, 'faulted');
    assert.equal(setup.session.fault, error);
    assert.equal(setup.gameSession.state, 'idle');
    assert.equal(setup.leases.length, 1, 'a failed old-session cleanup must not create a new lease');
    assert.equal(setup.leases[0]?.invalidations, 1);
    assert.equal(setup.getModuleDisposals(), 1);
  });
}

for (const operation of ['self-exit', 'switch'] as const) {
  test(`RuntimeSession invalidates once and faults when ${operation} disposal fails`, () => {
    const setup = makeLeaseSession();
    setup.session.handleLogin(fixture('player-login-room.json'));
    setup.setFailures('dispose');

    const error = caughtError(() => {
      if (operation === 'self-exit') setup.session.handleSelfExit({ raw: {} });
      else setup.session.handleServerSwitch(() => {});
    });

    assert.equal(setup.session.state, 'faulted');
    assert.equal(setup.session.fault, error);
    assert.equal(setup.gameSession.state, 'idle');
    assert.equal(setup.leases[0]?.invalidations, 1);
    assert.equal(setup.getModuleDisposals(), 1);
  });
}

test('RuntimeSession aggregates event, dispose, and invalidation failures after completing cleanup', () => {
  const setup = makeLeaseSession();
  setup.setFailures('event', 'dispose', 'invalidate');

  const error = caughtError(() => setup.session.handleLogin(fixture('player-login-room.json')));

  assert.equal(setup.session.state, 'faulted');
  assert.equal(setup.session.fault, error);
  assert.equal(setup.gameSession.state, 'idle');
  assert.equal(setup.leases[0]?.invalidations, 1);
  assert.deepEqual(
    (error as Error & { errors?: readonly unknown[] }).errors,
    [setup.errors.event, setup.errors.dispose, setup.errors.invalidate],
  );
});