import { describe, expect, it } from 'vitest';

import { Initializer } from '../../src/utils/initializer/initializer';

describe('Initializer', () => {
  it('should initialize with initializer', async () => {
    const initializer = new Initializer();

    expect(initializer.isInitialized('foo')).toBeFalsy();

    await initializer.initializeIfNecessary('foo', async () => {});
    expect(initializer.isInitialized('foo')).toBeTruthy();
  });

  it('should initialize without initializer', async () => {
    const initializer = new Initializer();

    expect(initializer.isInitialized('foo')).toBeFalsy();
    await initializer.initializeIfNecessary('foo');
    expect(initializer.isInitialized('foo')).toBeTruthy();
  });

  it('should initialize when already initialized', async () => {
    const initializer = new Initializer();

    expect(initializer.isInitialized('foo')).toBeFalsy();
    await initializer.initializeIfNecessary('foo', async () => {});
    await initializer.initializeIfNecessary('foo', async () => {});
    expect(initializer.isInitialized('foo')).toBeTruthy();
  });

  it('should not initialize when the initializer reports failure', async () => {
    const initializer = new Initializer();

    expect(await initializer.initializeIfNecessary('foo', async () => false)).toBe(
      false,
    );
    expect(initializer.isInitialized('foo')).toBeFalsy();

    expect(await initializer.initializeIfNecessary('foo', async () => true)).toBe(true);
    expect(initializer.isInitialized('foo')).toBeTruthy();
  });

  it('should report whether all of multiple aspects initialized', async () => {
    const initializer = new Initializer();

    expect(
      await initializer.initializeMultipleIfNecessary({
        foo: async () => false,
        bar: async () => {},
      }),
    ).toBe(false);
    expect(initializer.isInitialized('foo')).toBeFalsy();
    expect(initializer.isInitialized('bar')).toBeTruthy();

    expect(
      await initializer.initializeMultipleIfNecessary({
        foo: async () => true,
      }),
    ).toBe(true);
    expect(initializer.isInitialized('foo')).toBeTruthy();
  });

  it('should not initialize with failed initializer', async () => {
    const initializer = new Initializer();

    expect(initializer.isInitialized('foo')).toBeFalsy();
    await expect(
      initializer.initializeIfNecessary('foo', async () => {
        throw new Error('test');
      }),
    ).rejects.toThrow('test');
    expect(initializer.isInitialized('foo')).toBeFalsy();
  });

  it('should initialize multiple', async () => {
    const initializer = new Initializer();

    expect(initializer.isInitializedMultiple(['foo', 'bar'])).toBeFalsy();
    await expect(
      initializer.initializeMultipleIfNecessary({
        foo: async () => {},
        bar: async () => {
          throw new Error('test');
        },
      }),
    ).rejects.toThrow('test');

    expect(initializer.isInitializedMultiple(['foo', 'bar'])).toBeFalsy();

    await initializer.initializeMultipleIfNecessary({
      bar: async () => {},
    });

    expect(initializer.isInitializedMultiple(['foo', 'bar'])).toBeTruthy();
  });

  it('should uninitialize', async () => {
    const initializer = new Initializer();
    await initializer.initializeIfNecessary('foo');
    expect(initializer.isInitialized('foo')).toBeTruthy();

    initializer.uninitialize('foo');

    expect(initializer.isInitialized('foo')).toBeFalsy();
  });

  it('should discard an initialization that was uninitialized while it was running', async () => {
    const initializer = new Initializer();

    let finishInitializer: () => void = () => undefined;
    const initializing = initializer.initializeIfNecessary(
      'foo',
      () =>
        new Promise<void>((resolve) => {
          finishInitializer = resolve;
        }),
    );

    // A uninitialize lands while the initializer is still running.
    initializer.uninitialize('foo');

    finishInitializer();
    expect(await initializing).toBe(false);

    expect(initializer.isInitialized('foo')).toBeFalsy();
  });

  it('should initialize again after being uninitialized', async () => {
    const initializer = new Initializer();

    await initializer.initializeIfNecessary('foo');
    initializer.uninitialize('foo');
    expect(initializer.isInitialized('foo')).toBeFalsy();

    await initializer.initializeIfNecessary('foo');
    expect(initializer.isInitialized('foo')).toBeTruthy();
  });
});