import { getCompletions } from '../completion/completions';
import type { Situation } from '../completion/situation';
import type { DataProvider } from '../completion/DataProvider';

// Minimal mock DataProvider that returns empty data
function createMockDataProvider(overrides: Partial<DataProvider> = {}): DataProvider {
  return {
    getAllMetricNames: () => [],
    metricNamesToMetrics: (names: string[]) => names.map((name) => ({ name, help: '', type: '' })),
    fetchLabels: async () => [],
    fetchSeries: async () => [],
    fetchLabelValues: async () => [],
    getVariablesNames: () => [],
    durationVariablesCompletion: false,
    ...overrides,
  } as unknown as DataProvider;
}

describe('getCompletions', () => {
  const mockDataProvider = createMockDataProvider();

  describe('with keyword completion', () => {
    it('includes "with" in EMPTY completions', async () => {
      const situation: Situation = { type: 'EMPTY' };
      const completions = await getCompletions(situation, mockDataProvider);
      const withCompletion = completions.find((c) => c.label === 'with');
      expect(withCompletion).toBeDefined();
      expect(withCompletion!.insertText).toBe('with (');
      expect(withCompletion!.detail).toContain('cte_name');
    });

    it('includes "with" in AT_ROOT completions', async () => {
      const situation: Situation = { type: 'AT_ROOT' };
      const completions = await getCompletions(situation, mockDataProvider);
      const withCompletion = completions.find((c) => c.label === 'with');
      expect(withCompletion).toBeDefined();
    });

    it('includes "with" in IN_WITH_BODY completions', async () => {
      const situation: Situation = { type: 'IN_WITH_BODY' };
      const completions = await getCompletions(situation, mockDataProvider);
      const withCompletion = completions.find((c) => c.label === 'with');
      expect(withCompletion).toBeDefined();
    });

    it('includes "with" in IN_FUNCTION completions', async () => {
      const situation: Situation = { type: 'IN_FUNCTION' };
      const completions = await getCompletions(situation, mockDataProvider);
      const withCompletion = completions.find((c) => c.label === 'with');
      expect(withCompletion).toBeDefined();
    });
  });

  describe('Function completions', () => {
    it('includes standard PromQL functions', async () => {
      const situation: Situation = { type: 'AT_ROOT' };
      const completions = await getCompletions(situation, mockDataProvider);
      const sumCompletion = completions.find((c) => c.label === 'sum');
      expect(sumCompletion).toBeDefined();
      expect(sumCompletion!.type).toBe('FUNCTION');
    });
  });

  describe('Duration completions', () => {
    it('returns duration values for IN_DURATION', async () => {
      const situation: Situation = { type: 'IN_DURATION' };
      const completions = await getCompletions(situation, mockDataProvider);
      expect(completions.length).toBeGreaterThan(0);
      expect(completions.every((c) => c.type === 'DURATION')).toBe(true);
    });
  });
});