/**
 * The game session host (`src/server/session.ts`) — pure logic, no sockets, exercised directly.
 */

import { describe, it } from 'node:test';
import assert from 'node:assert/strict';

import type { GameConfig, PlayerIndex } from '../../src/engine/state.ts';
import type { Push } from '../../src/server/session.ts';
import { createSession, resumeSession } from '../../src/server/session.ts';

const config: GameConfig = {
  mode: 'competitive',
  days: 5,
  minCombinedRevenue: 0,
  maxCollisionsPerDay: 0,
  maxCollisionsTotal: 0,
  pvpCardsAllowed: false,
  optionalRules: {
    reducedVisibility: false,
    sisterTrains: false,
    employeeRotation: false,
    emergencyToolbox: false,
  },
};

describe('the game session host', () => {
  it('gives a fresh connect a full Frame — nothing nulled', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const push = session.connect(0 as PlayerIndex);
    assert.notEqual(push.frame.cells, null, 'a first connect nulled the board');
    assert.notEqual(push.frame.division, null, 'a first connect nulled the division');
  });

  it('only the current actor gets a real Menu; every other seat gets null', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const a = session.connect(0 as PlayerIndex);
    const b = session.connect(1 as PlayerIndex);
    const actorPushes = [a, b].filter((p) => p.menu !== null);
    assert.equal(actorPushes.length, 1, 'more than one seat (or zero) was given a real Menu');
  });

  it('rejects an intent from a seat that is not the current actor, with NOT_YOUR_TURN', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    // Whichever seat is NOT the current actor should be refused, regardless of the intent's content.
    const bPush = session.connect(1 as PlayerIndex);
    const notActor = (bPush.menu === null ? 1 : 0) as PlayerIndex;
    const result = session.intent(notActor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(result.accepted, false);
    if (!result.accepted) assert.equal(result.code, 'NOT_YOUR_TURN');
  });

  it('accepts a legal intent from the current actor and pushes every seat', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const aPush = session.connect(0 as PlayerIndex);
    const actor = (aPush.menu !== null ? 0 : 1) as PlayerIndex;

    const result = session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(result.accepted, true);
    if (result.accepted) assert.equal(result.pushes.size, 2, 'not every connected seat was pushed to');
  });

  it('rejects an illegal intent with its real RejectionCode, and does not remember the seq', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const aPush = session.connect(0 as PlayerIndex);
    const actor = (aPush.menu !== null ? 0 : 1) as PlayerIndex;

    // Discarding before ever drawing is illegal on an opening hand at the limit — a safe "this is
    // definitely rejected" fixture that does not depend on exactly which cards were dealt.
    const bad = session.intent(actor, 1, { type: 'card.discard', cardId: 'not-a-real-card', toSlot: 0 });
    assert.equal(bad.accepted, false);
    if (!bad.accepted) assert.ok(bad.code.length > 0, 'a rejection carried no code at all');

    // The same seq, now with a legal intent, must still go through — a rejection is not "applied".
    const retry = session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(retry.accepted, true, 'a seq burned by an earlier rejection could not be reused');
  });

  it('treats a repeated seq as an already-applied no-op, not a second application', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const aPush = session.connect(0 as PlayerIndex);
    const actor = (aPush.menu !== null ? 0 : 1) as PlayerIndex;

    const first = session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(first.accepted, true);
    const second = session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(second.accepted, true, 'a resend of an already-applied seq was rejected instead of ignored');
    if (second.accepted) assert.equal(second.pushes.size, 0, 'a resend produced pushes as if newly applied');
  });

  it('deltas the board on a second push when it has not changed since the first', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const aPush = session.connect(0 as PlayerIndex);
    session.connect(1 as PlayerIndex); // both seats need a baseline Frame before a delta means anything
    const actor = (aPush.menu !== null ? 0 : 1) as PlayerIndex;

    const result = session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(result.accepted, true);
    if (!result.accepted) return;
    // Choosing "draw" doesn't move a single card on the board — the division/cells should be nulled
    // on this push for a seat that already had them from `connect`.
    const push = result.pushes.get(actor)!;
    assert.equal(push.frame.division, null, 'the board was resent even though nothing on it changed');
  });

  it('only sends narration NEW since the last push to that specific seat', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const aPush = session.connect(0 as PlayerIndex);
    const actor = (aPush.menu !== null ? 0 : 1) as PlayerIndex;
    // A first connect is this seat's first contact, so it gets everything narrated so far (the
    // "Game Begins" intro and whatever `drain()` said entering the first Stage) — not an empty log.
    assert.ok(aPush.lines.length > 0, 'a first connect got no narration at all, not even the game-begins intro');

    const first = session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(first.accepted, true);
    if (!first.accepted) return;
    const firstLines = first.pushes.get(actor)!.lines;
    assert.ok(firstLines.length > 0, 'the acting seat got no narration for its own action');

    const second = session.intent(actor, 2, { type: 'draw.end' });
    assert.equal(second.accepted, true);
    if (!second.accepted) return;
    const secondLines = second.pushes.get(actor)!.lines;
    assert.ok(secondLines.length > 0, 'a second real action produced no narration at all');
    for (const line of firstLines) {
      assert.ok(!secondLines.includes(line), 'the second push repeated narration already sent in the first');
    }
  });
});

describe('turn timings (lobby-and-sessions.md §5)', () => {
  it('records a wall-clock span once the acting player, phase, Day or Stage changes', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    let pushes = new Map<PlayerIndex, Push>([
      [0 as PlayerIndex, session.connect(0 as PlayerIndex)],
      [1 as PlayerIndex, session.connect(1 as PlayerIndex)],
    ]);
    const seq = new Map<PlayerIndex, number>([[0 as PlayerIndex, 1], [1 as PlayerIndex, 1]]);
    const timings = [];

    for (let step = 0; step < 60 && timings.length === 0; step++) {
      const acting = [0, 1].find((seat) => pushes.get(seat as PlayerIndex)!.menu !== null) as PlayerIndex | undefined;
      const menu = acting === undefined ? null : pushes.get(acting)!.menu;
      if (acting === undefined || !menu || menu.options.length === 0) break;

      const n = seq.get(acting)!;
      seq.set(acting, n + 1);
      const result = session.intent(acting, n, menu.options[0]!);
      assert.equal(result.accepted, true, `step ${step}: ${JSON.stringify(menu.options[0])} rejected`);
      if (!result.accepted) break;
      if (result.timing) timings.push(result.timing);
      pushes = result.pushes;
    }

    assert.ok(timings.length > 0, 'no turn timing ever closed across 60 real steps of actual play');
    const [timing] = timings;
    assert.ok(timing!.endedAt >= timing!.startedAt, 'a span ended before it started');
    assert.ok([0, 1].includes(timing!.player), 'a timing named a player outside the table');
  });
});

describe('persistence hooks — exportSave / resumeSession (Phase 3)', () => {
  it('exportSave carries enough to reconstruct the exact same game', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    const push = session.connect(0 as PlayerIndex);
    const actor = (push.menu !== null ? 0 : 1) as PlayerIndex;
    const applied = session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });
    assert.equal(applied.accepted, true);

    const saved = session.exportSave();
    assert.equal(saved.seed, 42);
    assert.deepEqual(saved.playerNames, ['Alice', 'Bob']);
    assert.equal(saved.history.length, 1);
    assert.equal(saved.status, 'active');
    assert.ok(saved.createdAt > 0, 'createdAt was not set');

    const resumed = resumeSession(saved);
    const before = session.connect(actor);
    const after = resumed.connect(actor);
    assert.deepEqual(after.frame, before.frame, 'resumeSession did not reconstruct the same board/state');
  });

  it('a resumed session keeps enforcing whose turn it is', () => {
    const session = createSession(7, config, ['Alice', 'Bob']);
    const push = session.connect(0 as PlayerIndex);
    const actor = (push.menu !== null ? 0 : 1) as PlayerIndex;
    session.intent(actor, 1, { type: 'localOps.choose', option: 'draw' });

    const resumed = resumeSession(session.exportSave());
    const notActor = (actor === 0 ? 1 : 0) as PlayerIndex;
    const rejected = resumed.intent(notActor, 1, { type: 'draw.end' });
    assert.equal(rejected.accepted, false);
    if (!rejected.accepted) assert.equal(rejected.code, 'NOT_YOUR_TURN');
  });

  it('marks status finished only once the game actually is', () => {
    const session = createSession(42, config, ['Alice', 'Bob']);
    assert.equal(session.exportSave().status, 'active');
  });
});