import { describe, it, expect } from 'vitest';
import {
  addStamp, createLoyaltyState, currentProgram, DEFAULT_TRACKS, generosity, issueCard,
  joinProbability, returnVisitMultiplier, setProgram, StampTrack, validateTracks,
} from '../../src/sim/loyalty';

describe('loyalty', () => {
  it('starts with 10 purchase stamps for a used game up to 10 €', () => {
    const l = createLoyaltyState();
    expect(currentProgram(l)).toEqual({
      version: 1,
      tracks: [{ stampType: 'buy_new', slots: 10, reward: { kind: 'free_used_game', maxValueCents: 1000 } }],
    });
    expect(generosity(currentProgram(l))).toBe(100);
    expect(returnVisitMultiplier(currentProgram(l))).toBe(2);
    expect(joinProbability(currentProgram(l))).toBeCloseTo(0.25);
  });

  it('issues numbered cards on the current program', () => {
    const l = createLoyaltyState();
    const card = issueCard(l);
    expect(card).toEqual({ id: 'C0001', programVersion: 1, stamps: [0], pendingRewards: [], voucherCents: 0 });
    expect(issueCard(l).id).toBe('C0002');
  });

  it('earns the reward on the last stamp and resets the track', () => {
    const l = createLoyaltyState();
    const card = issueCard(l);
    for (let i = 0; i < 9; i++) expect(addStamp(l, card.id, 'buy_new')).toEqual([]);
    expect(addStamp(l, card.id, 'buy_new')).toEqual([{ kind: 'free_used_game', maxValueCents: 1000 }]);
    expect(card.stamps).toEqual([0]);
    expect(card.pendingRewards).toHaveLength(1);
  });

  it('ignores stamp types the card does not track', () => {
    const l = createLoyaltyState();
    const card = issueCard(l);
    expect(addStamp(l, card.id, 'trade')).toEqual([]);
    expect(card.stamps).toEqual([0]);
  });

  it('supports two independent stamp tracks', () => {
    const l = createLoyaltyState();
    setProgram(l, [
      { stampType: 'buy_new', slots: 3, reward: { kind: 'discount_percent', percent: 20 } },
      { stampType: 'trade', slots: 3, reward: { kind: 'free_trade' } },
    ]);
    const card = issueCard(l);
    addStamp(l, card.id, 'buy_new');
    addStamp(l, card.id, 'trade');
    addStamp(l, card.id, 'trade');
    expect(card.stamps).toEqual([1, 2]);
    expect(addStamp(l, card.id, 'trade')).toEqual([{ kind: 'free_trade' }]);
  });

  it('turns voucher rewards into card credit', () => {
    const l = createLoyaltyState();
    setProgram(l, [{ stampType: 'buy_used', slots: 3, reward: { kind: 'voucher', valueCents: 500 } }]);
    const card = issueCard(l);
    for (let i = 0; i < 3; i++) addStamp(l, card.id, 'buy_used');
    expect(card.voucherCents).toBe(500);
    expect(card.pendingRewards).toEqual([]);
  });

  it('validates tracks', () => {
    const reward = { kind: 'free_trade' } as const;
    const t = (stampType: StampTrack['stampType'], slots: number): StampTrack => ({ stampType, slots, reward });
    expect(validateTracks([])).toBe('1 ou 2 types de tampons');
    expect(validateTracks([t('buy_new', 5), t('trade', 5), t('buy_back', 5)])).toBe('1 ou 2 types de tampons');
    expect(validateTracks([t('buy_new', 5), t('buy_new', 5)])).toBe('Types de tampons en double');
    expect(validateTracks([t('buy_new', 2)])).toBe('Entre 3 et 20 cases par type');
    expect(validateTracks([t('buy_new', 21)])).toBe('Entre 3 et 20 cases par type');
    expect(validateTracks([t('buy_new', 3)])).toBeNull();
    expect(() => setProgram(createLoyaltyState(), [])).toThrow('1 ou 2 types de tampons');
  });

  it('keeps existing cards on the rules they were issued with', () => {
    const l = createLoyaltyState();
    const oldCard = issueCard(l);
    setProgram(l, [{ stampType: 'buy_new', slots: 3, reward: { kind: 'voucher', valueCents: 500 } }]);
    for (let i = 0; i < 3; i++) addStamp(l, oldCard.id, 'buy_new');
    expect(oldCard.stamps).toEqual([3]);
    expect(oldCard.voucherCents).toBe(0);
    expect(issueCard(l).programVersion).toBe(2);
  });

  it('penalizes reputation when the program becomes less generous', () => {
    const l = createLoyaltyState();
    const lessGenerous = setProgram(l, [{ stampType: 'buy_new', slots: 20, reward: { kind: 'voucher', valueCents: 500 } }]);
    expect(lessGenerous.reputationDelta).toBe(-2);
    const moreGenerous = setProgram(l, [{ stampType: 'buy_new', slots: 5, reward: { kind: 'voucher', valueCents: 1000 } }]);
    expect(moreGenerous.reputationDelta).toBe(0);
  });

  it('migrates a card to the current program once it completes a track', () => {
    const l = createLoyaltyState();
    const card = issueCard(l);
    setProgram(l, [{ stampType: 'buy_new', slots: 3, reward: { kind: 'voucher', valueCents: 500 } }]);
    for (let i = 0; i < 9; i++) expect(addStamp(l, card.id, 'buy_new')).toEqual([]);
    expect(addStamp(l, card.id, 'buy_new')).toEqual([{ kind: 'free_used_game', maxValueCents: 1000 }]);
    expect(card.programVersion).toBe(2);
    expect(card.stamps).toEqual([0]);
    expect(card.pendingRewards).toHaveLength(1);
    addStamp(l, card.id, 'buy_new');
    addStamp(l, card.id, 'buy_new');
    expect(addStamp(l, card.id, 'buy_new')).toEqual([{ kind: 'voucher', valueCents: 500 }]);
    expect(card.voucherCents).toBe(500);
  });

  it('stores deep copies of tracks', () => {
    const l = createLoyaltyState();
    const tracks: StampTrack[] = [{ stampType: 'buy_new', slots: 5, reward: { kind: 'free_trade' } }];
    setProgram(l, tracks);
    tracks[0].slots = 99;
    expect(currentProgram(l).tracks[0].slots).toBe(5);
    const first = l.programs[0].tracks[0];
    expect(first).not.toBe(DEFAULT_TRACKS[0]);
  });

  it('rejects non-integer slots and non-positive rewards', () => {
    const t = (slots: number, reward: StampTrack['reward']): StampTrack => ({ stampType: 'buy_new', slots, reward });
    expect(validateTracks([t(3.5, { kind: 'free_trade' })])).toBe('Entre 3 et 20 cases par type');
    expect(validateTracks([t(5, { kind: 'free_used_game', maxValueCents: 0 })])).toBe('Récompense invalide');
    expect(validateTracks([t(5, { kind: 'voucher', valueCents: -1 })])).toBe('Récompense invalide');
    expect(validateTracks([t(5, { kind: 'discount_percent', percent: 0 })])).toBe('Récompense invalide');
    expect(validateTracks([t(5, { kind: 'discount_percent', percent: 101 })])).toBe('Récompense invalide');
    expect(validateTracks([t(5, { kind: 'discount_percent', percent: 100 })])).toBeNull();
  });

  it('keeps partial progress on other tracks when migrating, capped to the new slots', () => {
    const l = createLoyaltyState();
    setProgram(l, [
      { stampType: 'buy_new', slots: 8, reward: { kind: 'free_trade' } },
      { stampType: 'trade', slots: 4, reward: { kind: 'free_trade' } },
    ]);
    const card = issueCard(l);
    card.stamps = [7, 3];
    setProgram(l, [
      { stampType: 'buy_new', slots: 5, reward: { kind: 'free_trade' } },
      { stampType: 'trade', slots: 4, reward: { kind: 'free_trade' } },
    ]);
    expect(addStamp(l, card.id, 'trade')).toEqual([{ kind: 'free_trade' }]);
    expect(card.programVersion).toBe(3);
    expect(card.stamps).toEqual([4, 0]);
  });
});