import { afterEach, describe, expect, it, vi } from 'vitest';
import { ProxmoxSchedulerService } from './proxmox-scheduler.service';

/**
 * ProxmoxSchedulerService.spec (Aufgabe 4) — Vorbild
 * `dkv-scheduler.service.spec.ts`: echte Fake-Registry (Map-basiert,
 * `getCronJob` wirft bei Unbekannt wie `@nestjs/schedule`), ECHTES `cron`
 * (Peer von `@nestjs/schedule`) — `cronTime.source` und `fireOnTick()`
 * sind die beobachtbaren Eigenschaften eines Auftrags.
 */

function makeFakeRegistry() {
  // biome-ignore lint/suspicious/noExplicitAny: Test-Attrappe
  const jobs = new Map<string, any>();
  return {
    __jobs: jobs,
    addCronJob: vi.fn((name: string, job: any) => {
      if (jobs.has(name)) throw new Error(`Cron Job with the given name (${name}) already exists.`);
      jobs.set(name, job);
    }),
    getCronJob: vi.fn((name: string) => {
      const job = jobs.get(name);
      if (!job) throw new Error(`No Cron Job was found with the given name (${name}).`);
      return job;
    }),
    deleteCronJob: vi.fn((name: string) => {
      const job = jobs.get(name);
      if (!job) throw new Error(`No Cron Job was found with the given name (${name}).`);
      jobs.delete(name);
    }),
    getCronJobs: vi.fn(() => jobs),
  };
}

interface FakeServerRow {
  id: string;
  tenantId: string;
  pollIntervalMin: number;
  isActive: boolean;
}

function makeFakeProxmoxService(
  servers: FakeServerRow[] | Error,
  options: { pollShouldThrowFor?: string[] } = {},
) {
  const polledServerIds: string[] = [];
  return {
    loadActiveServersForScheduler: vi.fn(async () => {
      if (servers instanceof Error) throw servers;
      return servers.filter((s) => s.isActive).map((s) => ({
        id: s.id,
        tenantId: s.tenantId,
        pollIntervalMin: s.pollIntervalMin,
      }));
    }),
    loadActiveServersForTenantScheduling: vi.fn(async (tenantId: string) => {
      if (servers instanceof Error) return [];
      return servers
        .filter((s) => s.isActive && s.tenantId === tenantId)
        .map((s) => ({ pollIntervalMin: s.pollIntervalMin }));
    }),
    listActiveServerIdsForTenant: vi.fn(async (tenantId: string) => {
      if (servers instanceof Error) return [];
      return servers.filter((s) => s.isActive && s.tenantId === tenantId).map((s) => s.id);
    }),
    pollServer: vi.fn(async (_tenantId: string, serverId: string) => {
      polledServerIds.push(serverId);
      if (options.pollShouldThrowFor?.includes(serverId)) {
        throw new Error(`poll boom for ${serverId}`);
      }
      return { reachable: true, errorKind: null, errorDetail: null, metrics: null, rawSample: null };
    }),
    __polledServerIds: polledServerIds,
  };
}

function makeScheduler(
  servers: FakeServerRow[] | Error,
  options: { pollShouldThrowFor?: string[] } = {},
) {
  const registry = makeFakeRegistry();
  const proxmoxService = makeFakeProxmoxService(servers, options);
  const scheduler = new ProxmoxSchedulerService(registry as any, proxmoxService as any);
  const logSpy = vi.spyOn((scheduler as any).logger, 'log').mockImplementation(() => undefined);
  const errorSpy = vi.spyOn((scheduler as any).logger, 'error').mockImplementation(() => undefined);
  return { registry, proxmoxService, scheduler, logSpy, errorSpy };
}

describe('ProxmoxSchedulerService — ein Auftrag je Mandant (Aufgabe 4, <behavior>)', () => {
  const registries: ReturnType<typeof makeFakeRegistry>[] = [];

  afterEach(() => {
    for (const registry of registries) {
      for (const job of registry.__jobs.values()) job.stop();
      registry.__jobs.clear();
    }
    registries.length = 0;
    vi.restoreAllMocks();
  });

  it('Beim Start registriert der Planer je Mandant mit mindestens einem aktiven Server genau einen Auftrag unter proxmox-poll:<tenantId>', async () => {
    const { registry, scheduler } = makeScheduler([
      { id: 's1', tenantId: 't1', pollIntervalMin: 15, isActive: true },
    ]);
    registries.push(registry);

    await scheduler.onApplicationBootstrap();

    expect([...registry.__jobs.keys()]).toEqual(['proxmox-poll:t1']);
    expect(registry.__jobs.get('proxmox-poll:t1').cronTime.source).toBe('*/15 * * * *');
  });

  it('Das Abfrageintervall eines Mandanten ist das KLEINSTE pollIntervalMin seiner aktiven Server', async () => {
    const { registry, scheduler } = makeScheduler([
      { id: 's1', tenantId: 't1', pollIntervalMin: 30, isActive: true },
      { id: 's2', tenantId: 't1', pollIntervalMin: 5, isActive: true },
    ]);
    registries.push(registry);

    await scheduler.onApplicationBootstrap();

    expect(registry.__jobs.get('proxmox-poll:t1').cronTime.source).toBe('*/5 * * * *');
  });

  it('Ein zweiter Mandant verdraengt den Auftrag des ersten nicht — beide Auftraege bestehen nebeneinander', async () => {
    const { registry, scheduler } = makeScheduler([
      { id: 's1', tenantId: 't1', pollIntervalMin: 15, isActive: true },
      { id: 's2', tenantId: 't2', pollIntervalMin: 10, isActive: true },
    ]);
    registries.push(registry);

    await scheduler.onApplicationBootstrap();

    expect(new Set(registry.__jobs.keys())).toEqual(new Set(['proxmox-poll:t1', 'proxmox-poll:t2']));
  });

  it('Keine aktiven Server bedeutet: kein Auftrag, ein Protokolleintrag, kein Fehler, nichts geloescht', async () => {
    const { registry, scheduler, logSpy, errorSpy } = makeScheduler([]);
    registries.push(registry);

    await scheduler.onApplicationBootstrap();

    expect(registry.__jobs.size).toBe(0);
    expect(logSpy).toHaveBeenCalled();
    expect(errorSpy).not.toHaveBeenCalled();
  });

  it('Ein Fehler beim Start wird gefangen und protokolliert, nie weitergeworfen', async () => {
    const { scheduler, errorSpy } = makeScheduler(new Error('DB weg'));

    await expect(scheduler.onApplicationBootstrap()).resolves.toBeUndefined();
    expect(errorSpy).toHaveBeenCalled();
  });

  it('Der Planer haengt an onApplicationBootstrap, nicht an onModuleInit', () => {
    const registry = makeFakeRegistry();
    const scheduler = new ProxmoxSchedulerService(registry as any, {} as any);
    expect(typeof (scheduler as unknown as { onApplicationBootstrap?: unknown }).onApplicationBootstrap).toBe(
      'function',
    );
    expect((scheduler as unknown as { onModuleInit?: unknown }).onModuleInit).toBeUndefined();
  });

  it('Der Tick eines Mandanten geht ueber dessen Server und fragt jeden einzeln ab; ein fehlgeschlagener Server bricht die Schleife nicht ab', async () => {
    const { registry, scheduler, proxmoxService, errorSpy } = makeScheduler(
      [
        { id: 's1', tenantId: 't1', pollIntervalMin: 5, isActive: true },
        { id: 's2', tenantId: 't1', pollIntervalMin: 5, isActive: true },
      ],
      { pollShouldThrowFor: ['s1'] },
    );
    registries.push(registry);
    await scheduler.onApplicationBootstrap();

    registry.__jobs.get('proxmox-poll:t1').fireOnTick();
    await new Promise((resolve) => setImmediate(resolve));

    expect((proxmoxService as any).__polledServerIds).toEqual(['s1', 's2']);
    expect(errorSpy).toHaveBeenCalled();
  });

  it('refreshTenant zieht den Auftrag eines Mandanten sofort nach — ohne Neustart', async () => {
    const { registry, scheduler } = makeScheduler([]);
    registries.push(registry);
    await scheduler.onApplicationBootstrap();
    expect(registry.__jobs.size).toBe(0);

    (scheduler as any).proxmoxService.loadActiveServersForTenantScheduling = vi.fn(async () => [
      { pollIntervalMin: 20 },
    ]);

    await scheduler.refreshTenant('t1');

    expect(registry.__jobs.get('proxmox-poll:t1').cronTime.source).toBe('*/20 * * * *');
  });

  it('refreshTenant entfernt den Auftrag, wenn keine aktiven Server mehr uebrig sind', async () => {
    const { registry, scheduler } = makeScheduler([
      { id: 's1', tenantId: 't1', pollIntervalMin: 15, isActive: true },
    ]);
    registries.push(registry);
    await scheduler.onApplicationBootstrap();
    expect(registry.__jobs.has('proxmox-poll:t1')).toBe(true);

    (scheduler as any).proxmoxService.loadActiveServersForTenantScheduling = vi.fn(async () => []);
    await scheduler.refreshTenant('t1');

    expect(registry.__jobs.has('proxmox-poll:t1')).toBe(false);
  });
});