import { describe, expect, it } from 'vitest';
import { ObjectId } from 'mongodb';
import { decideSend } from '../src/mode.js';
import { assertBatchWithinLimit, BatchTooLargeError } from '../src/limits.js';
import type { Config } from '../src/config.js';
import type { NotificationDoc } from '../src/types.js';

function baseCfg(over: Partial<Config> = {}): Config {
  return {
    mode: 'full',
    killSwitch: false,
    ownedChannels: ['fcm'],
    mongoUrl: 'mongodb://x',
    dbName: 'fuegos',
    redis: { host: 'x', port: 6379, db: 0 },
    poll: { intervalMs: 1000, batchSize: 100 },
    limits: { perUserPerDay: 20, maxPerBatch: 2000 },
    canary: { userIds: [], subsIds: [] },
    retries: { attempts: 3, backoffMs: 100 },
    fcm: {},
    email: { from: 'x' },
    rootUrl: 'https://x/',
    gmaps: {},
    logLevel: 'silent',
    serviceName: 'test',
    ...over,
  };
}

const notif: NotificationDoc = {
  _id: new ObjectId(),
  userId: 'u1',
  subsId: new ObjectId('bbbbbbbbbbbbbbbbbbbbbbbb'),
  content: 'x',
  geo: { type: 'Point', coordinates: [0, 0] },
  type: 'mobile',
  when: new Date(),
  sealed: 's',
};

describe('decideSend', () => {
  it('kill switch overrides every mode', () => {
    for (const mode of ['dry-run', 'shadow', 'canary', 'full'] as const) {
      const d = decideSend(baseCfg({ mode, killSwitch: true }), notif);
      expect(d).toEqual({ send: false, reason: 'kill-switch' });
    }
  });
  it('dry-run never sends', () => {
    expect(decideSend(baseCfg({ mode: 'dry-run' }), notif)).toEqual({ send: false, reason: 'dry-run' });
  });
  it('shadow never sends', () => {
    expect(decideSend(baseCfg({ mode: 'shadow' }), notif)).toEqual({ send: false, reason: 'shadow' });
  });
  it('canary sends only to cohort by userId', () => {
    expect(decideSend(baseCfg({ mode: 'canary', canary: { userIds: ['u1'], subsIds: [] } }), notif)).toEqual({ send: true });
    expect(decideSend(baseCfg({ mode: 'canary', canary: { userIds: ['other'], subsIds: [] } }), notif)).toEqual({ send: false, reason: 'not-in-canary' });
  });
  it('canary sends to cohort by subsId', () => {
    expect(decideSend(baseCfg({ mode: 'canary', canary: { userIds: [], subsIds: ['bbbbbbbbbbbbbbbbbbbbbbbb'] } }), notif)).toEqual({ send: true });
  });
  it('full always sends', () => {
    expect(decideSend(baseCfg({ mode: 'full' }), notif)).toEqual({ send: true });
  });
});

describe('circuit breaker', () => {
  it('throws when batch exceeds max', () => {
    expect(() => assertBatchWithinLimit(2001, 2000)).toThrow(BatchTooLargeError);
  });
  it('passes when within max', () => {
    expect(() => assertBatchWithinLimit(2000, 2000)).not.toThrow();
  });
  it('unlimited when max is 0', () => {
    expect(() => assertBatchWithinLimit(999999, 0)).not.toThrow();
  });
});