import { BadRequestException, NotFoundException } from '@nestjs/common';
import { TaskTemplatesService } from './task-templates.service';
import { PrismaService } from '../prisma/prisma.service';
import { AuditLogService } from '../audit/audit-log.service';
import { WebhooksService } from '../webhooks/webhooks.service';

describe('TaskTemplatesService', () => {
  let service: TaskTemplatesService;
  let prisma: {
    taskTemplate: {
      findMany: jest.Mock;
      findUnique: jest.Mock;
      create: jest.Mock;
      update: jest.Mock;
      updateMany: jest.Mock;
    };
    task: { create: jest.Mock };
  };
  let auditLog: { record: jest.Mock };
  let webhooks: { dispatch: jest.Mock };

  const template = {
    id: 'template-1',
    title: 'Varroa-Kontrolle',
    description: null,
    priority: 'NORMAL',
    assignedUserId: null,
    recurrenceType: 'MONTHLY',
    recurrenceMonth: null,
    recurrenceDayOfMonth: 15,
    intervalDays: null,
    nextDueDate: new Date('2026-03-15T00:00:00.000Z'),
    active: true,
  };

  beforeEach(() => {
    prisma = {
      taskTemplate: {
        findMany: jest.fn(),
        findUnique: jest.fn(),
        create: jest.fn(),
        update: jest.fn(),
        updateMany: jest.fn(),
      },
      task: { create: jest.fn() },
    };
    auditLog = { record: jest.fn().mockResolvedValue(undefined) };
    webhooks = { dispatch: jest.fn().mockResolvedValue(undefined) };
    service = new TaskTemplatesService(
      prisma as unknown as PrismaService,
      auditLog as unknown as AuditLogService,
      webhooks as unknown as WebhooksService,
    );
  });

  it('findById throws NotFoundException when missing', async () => {
    prisma.taskTemplate.findUnique.mockResolvedValue(null);
    await expect(service.findById('missing')).rejects.toBeInstanceOf(
      NotFoundException,
    );
  });

  it('create rejects YEARLY without recurrenceMonth/recurrenceDayOfMonth', async () => {
    await expect(
      service.create(
        { title: 'Jahresinventur', recurrenceType: 'YEARLY' },
        'user-1',
      ),
    ).rejects.toBeInstanceOf(BadRequestException);
    expect(prisma.taskTemplate.create).not.toHaveBeenCalled();
  });

  it('create rejects MONTHLY without recurrenceDayOfMonth', async () => {
    await expect(
      service.create(
        { title: 'Monatscheck', recurrenceType: 'MONTHLY' },
        'user-1',
      ),
    ).rejects.toBeInstanceOf(BadRequestException);
  });

  it('create rejects INTERVAL_DAYS without intervalDays', async () => {
    await expect(
      service.create(
        { title: 'Fütterung', recurrenceType: 'INTERVAL_DAYS' },
        'user-1',
      ),
    ).rejects.toBeInstanceOf(BadRequestException);
  });

  it('create computes nextDueDate and stores the acting user as creator', async () => {
    prisma.taskTemplate.create.mockResolvedValue(template);

    await service.create(
      {
        title: 'Varroa-Kontrolle',
        recurrenceType: 'MONTHLY',
        recurrenceDayOfMonth: 15,
      },
      'user-1',
    );

    const [[createArg]] = prisma.taskTemplate.create.mock.calls as [
      [{ data: { nextDueDate: Date; createdByUserId: string } }],
    ];
    expect(createArg.data.nextDueDate).toBeInstanceOf(Date);
    expect(createArg.data.createdByUserId).toBe('user-1');
  });

  it('update recomputes nextDueDate only when a recurrence field changes', async () => {
    prisma.taskTemplate.findUnique.mockResolvedValue(template);
    prisma.taskTemplate.update.mockResolvedValue(template);

    await service.update('template-1', { title: 'Neuer Titel' }, 'user-1');

    const [[updateArg]] = prisma.taskTemplate.update.mock.calls as [
      [{ data: { nextDueDate: Date | undefined } }],
    ];
    expect(updateArg.data.nextDueDate).toBeUndefined();
  });

  it('update recomputes nextDueDate when recurrenceDayOfMonth changes', async () => {
    prisma.taskTemplate.findUnique.mockResolvedValue(template);
    prisma.taskTemplate.update.mockResolvedValue(template);

    await service.update('template-1', { recurrenceDayOfMonth: 20 }, 'user-1');

    const [[updateArg]] = prisma.taskTemplate.update.mock.calls as [
      [{ data: { nextDueDate: Date | undefined } }],
    ];
    expect(updateArg.data.nextDueDate).toBeInstanceOf(Date);
  });

  it('deactivate sets active to false', async () => {
    prisma.taskTemplate.findUnique.mockResolvedValue(template);
    prisma.taskTemplate.update.mockResolvedValue({
      ...template,
      active: false,
    });

    await service.deactivate('template-1', 'user-1');

    const [[updateArg]] = prisma.taskTemplate.update.mock.calls as [
      [{ data: { active: boolean } }],
    ];
    expect(updateArg.data.active).toBe(false);
  });

  describe('generateDueTasks', () => {
    it('creates a Task and advances nextDueDate for a due template', async () => {
      prisma.taskTemplate.findMany.mockResolvedValue([template]);
      prisma.taskTemplate.updateMany.mockResolvedValue({ count: 1 });
      prisma.task.create.mockResolvedValue({ id: 'task-1' });

      await service.generateDueTasks();

      const [[createArg]] = prisma.task.create.mock.calls as [
        [{ data: { title: string; sourceTemplateId: string } }],
      ];
      expect(createArg.data.title).toBe(template.title);
      expect(createArg.data.sourceTemplateId).toBe(template.id);
      expect(webhooks.dispatch).toHaveBeenCalledWith(
        'task.created',
        expect.objectContaining({ id: 'task-1' }),
      );
    });

    it('skips Task creation when the compare-and-swap claim loses the race', async () => {
      prisma.taskTemplate.findMany.mockResolvedValue([template]);
      prisma.taskTemplate.updateMany.mockResolvedValue({ count: 0 });

      await service.generateDueTasks();

      expect(prisma.task.create).not.toHaveBeenCalled();
      expect(webhooks.dispatch).not.toHaveBeenCalled();
    });

    it('does nothing when no template is due', async () => {
      prisma.taskTemplate.findMany.mockResolvedValue([]);

      await service.generateDueTasks();

      expect(prisma.taskTemplate.updateMany).not.toHaveBeenCalled();
      expect(prisma.task.create).not.toHaveBeenCalled();
    });
  });
});