import test from 'node:test';
import assert from 'node:assert/strict';
import { createEnsureYomitanExtensionLoadedHandler } from './yomitan-extension-loader';

test('ensure yomitan loader returns existing extension when available', async () => {
  const extension = { id: 'ext' } as never;
  const ensureLoaded = createEnsureYomitanExtensionLoadedHandler({
    getYomitanExtension: () => extension,
    getLoadInFlight: () => null,
    setLoadInFlight: () => {
      throw new Error('unexpected');
    },
    loadYomitanExtension: async () => {
      throw new Error('unexpected');
    },
  });

  assert.equal(await ensureLoaded(), extension);
});

test('ensure yomitan loader reuses in-flight promise', async () => {
  const extension = { id: 'ext' } as never;
  const inflight = Promise.resolve(extension);
  const ensureLoaded = createEnsureYomitanExtensionLoadedHandler({
    getYomitanExtension: () => null,
    getLoadInFlight: () => inflight,
    setLoadInFlight: () => {
      throw new Error('unexpected');
    },
    loadYomitanExtension: async () => {
      throw new Error('unexpected');
    },
  });

  assert.equal(await ensureLoaded(), extension);
});

test('ensure yomitan loader starts load and clears in-flight when done', async () => {
  const calls: string[] = [];
  let inFlight: Promise<any> | null = null;
  const extension = { id: 'ext' } as never;
  const ensureLoaded = createEnsureYomitanExtensionLoadedHandler({
    getYomitanExtension: () => null,
    getLoadInFlight: () => inFlight,
    setLoadInFlight: (promise) => {
      inFlight = promise;
      calls.push(promise ? 'set:promise' : 'set:null');
    },
    loadYomitanExtension: async () => {
      calls.push('load');
      return extension;
    },
  });

  assert.equal(await ensureLoaded(), extension);
  assert.deepEqual(calls, ['load', 'set:promise', 'set:null']);
});