ApiCore/ApiCore-Backend/src/reminders/task-due.handlers.spec.ts

import type { Prisma } from '../../generated/prisma';
import type { AnyDomainEventEnvelope } from '../domain-events/domain-event-types';
import { domainEventHandlerMetadata } from '../domain-events/on-domain-event.decorator';
import type { NotificationsService } from '../notifications/notifications.service';
import { TaskDueHandlers } from './task-due.handlers';

function taskDue(
  taskId = 'task-1',
  dueOn = '2026-06-10',
): AnyDomainEventEnvelope<'TaskDue'> {
  return {
    id: 'evt-1',
    type: 'TaskDue',
    aggregateType: 'Task',
    aggregateId: taskId,
    payload: { dueOn },
    actorUserId: null,
    correlationId: 'cor-1',
    occurredAt: new Date(),
    attempts: 0,
  };
}

type RecordCall = [string[], Record<string, unknown>, unknown];

describe('TaskDueHandlers', () => {
  let task: Record<string, unknown> | null;
  let completers: { id: string }[];
  let disabled: { userId: string }[];
  let taskFindUnique: jest.Mock;
  let userFindMany: jest.Mock;
  let preferenceFindMany: jest.Mock;
  let recordForUsers: jest.Mock;
  let handlers: TaskDueHandlers;
  const tx = {} as Prisma.TransactionClient;

  beforeEach(() => {
    jest.useFakeTimers({ now: new Date('2026-06-10T08:00:00.000Z') });
    task = {
      id: 'task-1',
      title: 'Waben pruefen',
      status: 'OPEN',
      assignedUserId: 'u-assignee',
      dueDate: new Date('2026-06-10T00:00:00.000Z'),
    };
    completers = [{ id: 'u-a' }, { id: 'u-b' }];
    disabled = [];
    taskFindUnique = jest.fn(() => Promise.resolve(task));
    userFindMany = jest.fn(() => Promise.resolve(completers));
    preferenceFindMany = jest.fn(() => Promise.resolve(disabled));
    recordForUsers = jest.fn().mockResolvedValue([]);
    const client = {
      task: { findUnique: taskFindUnique },
      user: { findMany: userFindMany },
      notificationPreference: { findMany: preferenceFindMany },
    } as unknown as Prisma.TransactionClient;
    handlers = new TaskDueHandlers({
      recordForUsers,
    } as unknown as NotificationsService);
    Object.assign(tx, client);
  });

  const firstCall = (): RecordCall =>
    recordForUsers.mock.calls[0] as RecordCall;

  afterEach(() => jest.useRealTimers());

  it('is registered as notifications.task-due for TaskDue', () => {
    const entries = domainEventHandlerMetadata(
      // eslint-disable-next-line @typescript-eslint/unbound-method
      TaskDueHandlers.prototype.taskDue,
    );

    expect(entries).toEqual([
      { types: ['TaskDue'], handlerId: 'notifications.task-due' },
    ]);
  });

  it('notifies the assignee only', async () => {
    await handlers.taskDue(taskDue(), tx);

    expect(userFindMany).not.toHaveBeenCalled();
    expect(recordForUsers).toHaveBeenCalledTimes(1);
    expect(firstCall()[0]).toEqual(['u-assignee']);
  });

  it('without an assignee notifies holders of tasks:complete', async () => {
    task = { ...task, assignedUserId: null };

    await handlers.taskDue(taskDue(), tx);

    expect(userFindMany).toHaveBeenCalledWith(
      expect.objectContaining({
        where: {
          isActive: true,
          role: {
            status: 'ACTIVE',
            permissions: { some: { permission: { key: 'tasks:complete' } } },
          },
        },
      }),
    );
    expect(firstCall()[0]).toEqual(['u-a', 'u-b']);
  });

  it('writes nothing for a user with taskDueEnabled false', async () => {
    task = { ...task, assignedUserId: null };
    disabled = [{ userId: 'u-a' }];

    await handlers.taskDue(taskDue(), tx);

    expect(preferenceFindMany).toHaveBeenCalledWith({
      where: { userId: { in: ['u-a', 'u-b'] }, taskDueEnabled: false },
      select: { userId: true },
    });
    expect(firstCall()[0]).toEqual(['u-b']);
  });

  it('writes nothing when the only recipient switched it off', async () => {
    disabled = [{ userId: 'u-assignee' }];

    await handlers.taskDue(taskDue(), tx);

    expect(recordForUsers).not.toHaveBeenCalled();
  });

  it('uses the key task-due:<taskId>:<day> as prefix, so rows end in :<userId>', async () => {
    task = { ...task, dueDate: new Date('2026-06-09T00:00:00.000Z') };

    await handlers.taskDue(taskDue('task-1', '2026-06-09'), tx);

    expect(firstCall()[1]).toEqual({
      priority: 'HINWEIS',
      category: 'TASK_DUE',
      message: 'Fällig seit 09.06.: Waben pruefen',
      relatedType: 'Task',
      relatedId: 'task-1',
      link: '/tasks',
      requiredPermissions: ['tasks:read'],
      dedupeKeyPrefix: 'task-due:task-1:2026-06-09',
    });
    expect(firstCall()[2]).toBe(tx);
  });

  it.each(['DONE', 'CANCELLED'])('skips a %s task', async (status) => {
    task = { ...task, status };

    await handlers.taskDue(taskDue(), tx);

    expect(recordForUsers).not.toHaveBeenCalled();
  });

  it('says "Heute fällig" for an event of today', async () => {
    await handlers.taskDue(taskDue(), tx);

    expect(firstCall()[1].message).toBe('Heute fällig: Waben pruefen');
  });

  it('says "Fällig seit {TT.MM.}" for a catch-up event', async () => {
    task = { ...task, dueDate: new Date('2026-06-07T00:00:00.000Z') };

    await handlers.taskDue(taskDue('task-1', '2026-06-07'), tx);

    expect(firstCall()[1].message).toBe('Fällig seit 07.06.: Waben pruefen');
  });

  it('skips a task whose due day was moved after the event', async () => {
    task = { ...task, dueDate: new Date('2026-06-20T00:00:00.000Z') };

    await handlers.taskDue(taskDue('task-1', '2026-06-10'), tx);

    expect(recordForUsers).not.toHaveBeenCalled();
  });

  it('skips a task whose due date was removed', async () => {
    task = { ...task, dueDate: null };

    await handlers.taskDue(taskDue(), tx);

    expect(recordForUsers).not.toHaveBeenCalled();
  });

  it('accepts an IN_PROGRESS task', async () => {
    task = { ...task, status: 'IN_PROGRESS' };

    await handlers.taskDue(taskDue(), tx);

    expect(recordForUsers).toHaveBeenCalledTimes(1);
  });

  it('skips a task that no longer exists', async () => {
    task = null;

    await handlers.taskDue(taskDue(), tx);

    expect(recordForUsers).not.toHaveBeenCalled();
  });

  it('cuts the title to 200 characters', async () => {
    task = { ...task, title: 'x'.repeat(300) };

    await handlers.taskDue(taskDue(), tx);

    const input = firstCall()[1];
    expect(input.message).toBe(`Heute fällig: ${'x'.repeat(200)}`);
  });

  it('writes nothing when no user holds tasks:complete', async () => {
    task = { ...task, assignedUserId: null };
    completers = [];

    await handlers.taskDue(taskDue(), tx);

    expect(recordForUsers).not.toHaveBeenCalled();
  });
});