import type { Server } from 'bun';
import { afterEach, beforeEach, describe, expect, it } from 'bun:test';
import HttpRouter from '../../HttpRouter/HttpRouter';
import { etags } from './etags';

describe('etags middleware', () => {
  const helloWorldEtag = '"c6a1dfa4103602ad"';
  let server: Server;
  let app: HttpRouter;
  beforeEach(() => {
    app = new HttpRouter();
    app.use(etags());
    server = app.listen({ port: 0 });
  });
  afterEach(() => {
    server.stop(true);
  });
  it('should return empty response for matching hash', async () => {
    app.get('/', c => c.text('Hello world'));
    const resp = await fetch(server.url, {
      headers: {
        'If-None-Match': helloWorldEtag,
      },
    });
    const text = await resp.text();
    expect(resp.status).toBe(204);
    expect(resp.headers.get('Etag')).toBe(helloWorldEtag);
    expect(text).toBe('');
  });
  it('should match when multiple etags are given', async () => {
    app.get('/', c => c.text('Hello world'));
    const resp = await fetch(server.url, {
      headers: {
        'If-None-Match': `"abc", ${helloWorldEtag}`,
      },
    });
    const text = await resp.text();
    expect(resp.status).toBe(204);
    expect(resp.headers.get('Etag')).toBe(helloWorldEtag);
    expect(text).toBe('');
  });
  it('should return full response for mismatch', async () => {
    app.get('/', c => c.text('Hello world'));
    const mismatchEtag = '"mismatch"';
    const resp = await fetch(server.url, {
      headers: {
        'If-None-Match': mismatchEtag,
      },
    });
    const text = await resp.text();
    expect(resp.status).toBe(204);
    expect(resp.headers.get('Etag')).toBe(helloWorldEtag);
    expect(text).toBe('');
  });
  it('should not generate for non-200', async () => {
    app.get('/', c => c.text('Hello world', { status: 404 }));
    const resp = await fetch(server.url, {
      headers: {
        'If-None-Match': helloWorldEtag,
      },
    });
    const text = await resp.text();
    expect(resp.status).toBe(404);
    expect(resp.headers.has('Etag')).toBe(false);
    expect(text).toBe('Hello world');
  });
  it('should not generate for non-GET', async () => {
    app.post('/', c => c.text('Hello world'));
    const resp = await fetch(server.url, {
      method: 'POST',
      headers: {
        'If-None-Match': helloWorldEtag,
      },
    });
    const text = await resp.text();
    expect(resp.status).toBe(412);
    expect(resp.headers.has('Etag')).toBe(true);
    expect(text).toBe('');
  });
  it('should not generate for streams', async () => {
    app.post('/', c => {
      const encoder = new TextEncoder();

      const readable = new ReadableStream({
        async start(controller) {
          try {
            controller.enqueue(encoder.encode('Hello world'));
          } catch (err) {
            console.error('error streaming response');
          } finally {
            controller.close();
          }
        },
      });
      return new Response(readable, {
        headers: {
          'Content-Type': 'text/stream',
          'Transfer-Encoding': 'chunked',
          'Cache-Control': 'no-cache',
          Connection: 'keep-alive',
        },
      });
    });
    const resp = await fetch(server.url, {
      method: 'POST',
      headers: {
        'If-None-Match': helloWorldEtag,
      },
    });
    expect(resp.status).toBe(200);
    expect(resp.headers.has('Etag')).toBe(false);
  });
});