// HTTP as FILIUS writes it (http.ts), and the web server and browser
// (apps/web.ts) where webJava.test.ts's stories do not go.

import { describe, expect, it } from 'vitest';
import {
  decodeUriPath,
  deviceConfiguration,
  encodeUriPath,
  formatHttpRequest,
  formatHttpResponse,
  imageSources,
  javaBase64,
  javaBase64Decode,
  parseHttpRequest,
  parseHttpResponse,
  VirtualFileSystem,
  webBrowserAddress,
  type NetworkRuntimeEngine,
  type TopologySnapshotInput,
} from '../src/index.js';
import { link, pc, startedEngine, uuid } from './fixtures.js';

describe('HTTP as FILIUS writes it', () => {
  it('writes a request with the path encoded and without its query, and a POST with its data', () => {
    expect(formatHttpRequest({ method: 'GET', path: '/mein bild.html?x=1', host: 'www.filius.de' })).toBe('GET /mein%20bild.html HTTP/1.1\nHost: www.filius.de\n');
    expect(formatHttpRequest({ method: 'POST', path: '', host: undefined, data: 'a=b' })).toBe('POST / HTTP/1.1\n\na=b');
  });

  it('reads a request: method in any case, Host header, POST data after the empty line', () => {
    expect(parseHttpRequest('post /form%C3%BC HTTP/1.0\nhost: a.de\n\nx=1\ny=2')).toEqual({
      type: 'request',
      request: { method: 'post', path: '/formü', protocolVersion: 'HTTP/1.0', host: 'a.de', data: '\nx=1\ny=2' },
    });
  });

  it('answers what it cannot read with 400 or 501, and takes a request without a version as HTTP/1.1 (Java: the thread dies)', () => {
    expect(parseHttpRequest('')).toEqual({ type: 'invalid', statusCode: 400 });
    expect(parseHttpRequest('GET')).toEqual({ type: 'invalid', statusCode: 400 });
    expect(parseHttpRequest('HALLO Welt')).toEqual({ type: 'invalid', statusCode: 501 });
    expect(parseHttpRequest('GET /%zz HTTP/1.1')).toEqual({ type: 'invalid', statusCode: 400 });
    expect(parseHttpRequest('GET /')).toMatchObject({ type: 'request', request: { path: '/', protocolVersion: 'HTTP/1.1' } });
  });

  it('writes and reads a response', () => {
    const text = formatHttpResponse({ protocolVersion: 'HTTP/1.1', statusCode: 200, contentType: 'text/html', body: '<p>\n</p>' });
    expect(text).toBe('HTTP/1.1 200 OK\nContent-type: text/html\n\n<p>\n</p>');
    expect(parseHttpResponse(text)).toEqual({ protocolVersion: 'HTTP/1.1', statusCode: 200, contentType: 'text/html', body: '<p>\n</p>' });
    expect(parseHttpResponse('HTTP/1.1 404 Not Found\n')).toEqual({ protocolVersion: 'HTTP/1.1', statusCode: 404, contentType: undefined, body: undefined });
    expect(parseHttpResponse('HTTP/1.1 200 OK\ncontent-TYPE: image/png\n\nx')).toMatchObject({ contentType: 'image/png', body: 'x' });
    expect(parseHttpResponse('Hallo Welt')).toBeUndefined();
  });

  it('encodes a path as Spring UriUtils.encodePath and decodes it back', () => {
    expect(encodeUriPath("/a b/ü?#%[]-._~!$&'()*+,;=:@")).toBe("/a%20b/%C3%BC%3F%23%25%5B%5D-._~!$&'()*+,;=:@");
    expect(decodeUriPath('/a%20b/%C3%BC+')).toBe('/a b/ü+');
    expect(decodeUriPath('/50%')).toBeUndefined();
  });

  it('reads and writes Base64 as FILIUS does, line breaks and all', () => {
    const bytes = new Uint8Array(100).map((_, index) => index * 7);
    expect(javaBase64Decode(javaBase64(bytes))).toEqual(bytes);
    expect(javaBase64Decode('QUJD\nRA==')).toEqual(new TextEncoder().encode('ABCD'));
    expect(javaBase64Decode('QUJ')).toBeUndefined();
    expect(javaBase64Decode('QU=D')).toBeUndefined();
  });
});

describe("the browser's address line (erzeugeURL)", () => {
  it('takes a host with or without http://, the path without a final slash', () => {
    expect(webBrowserAddress('www.filius.de')).toEqual({ host: 'www.filius.de', path: '/' });
    expect(webBrowserAddress('HTTP://192.168.0.30/a/b/')).toEqual({ host: '192.168.0.30', path: '/a/b' });
    expect(webBrowserAddress('http:///text.txt')).toEqual({ host: '', path: '/text.txt' });
    expect(webBrowserAddress('/text.txt')).toEqual({ host: '', path: '/text.txt' });
  });

  it('is no address for what Java does not take as a host', () => {
    expect(webBrowserAddress('www.filius.de:8080/')).toBeUndefined();
    expect(webBrowserAddress('1fehler.de')).toBeUndefined();
    expect(webBrowserAddress('http:')).toBeUndefined();
  });
});

describe('the images of a page', () => {
  it('finds each img tag, in any case, its src in any quotes', () => {
    expect(imageSources('<img src="a.png"><IMG SRC=\'b.png\'> <img alt="x" src=c/d.png><img\nsrc = "e.png" /><imgx src="no.png"><img alt="no src">')).toEqual([
      'a.png',
      'b.png',
      'c/d.png',
      'e.png',
    ]);
  });
});

const SERVER = uuid(0x3001);
const CLIENT = uuid(0x3002);

function network(files: VirtualFileSystem, changes: Partial<TopologySnapshotInput> = {}): TopologySnapshotInput {
  return {
    nodes: [pc(SERVER, uuid(0x3011)), pc(CLIENT, uuid(0x3012))],
    links: [link(SERVER, uuid(0x3011), CLIENT, uuid(0x3012))],
    deviceConfigurations: new Map([
      [SERVER, deviceConfiguration('10.0.0.1', '255.255.255.0', '', '')],
      [CLIENT, deviceConfiguration('10.0.0.2', '255.255.255.0', '', '')],
    ]),
    webServersByNodeId: new Map([[SERVER, { port: 80, documentRoot: '/webserver', virtualHosts: false, isActive: true }]]),
    webBrowserNodeIds: new Set([CLIENT]),
    fileSystemsByNodeId: new Map([[SERVER, files]]),
    ...changes,
  };
}

function files(entries: Record<string, string>): VirtualFileSystem {
  const fileSystem = new VirtualFileSystem();
  fileSystem.createDirectory('/webserver', true);
  for (const [path, text] of Object.entries(entries)) {
    const parent = path.slice(0, path.lastIndexOf('/'));
    if (parent !== '' && !fileSystem.contains(parent)) fileSystem.createDirectory(parent, true);
    fileSystem.writeTextFile(path, text);
  }
  return fileSystem;
}

/** The server's answers to the requests, one after the other over one connection. */
function ask(engine: NetworkRuntimeEngine, ...requests: string[]): string[] {
  const socket = engine.openTcpClientSocket(CLIENT, '10.0.0.1', 80)!;
  expect(engine.connectTcpWithResult(socket)).toBe('connected');
  return requests.map((request) => {
    expect(engine.sendTcp(socket, new TextEncoder().encode(request))).toBe(true);
    engine.handle({ type: 'advance', toMilliseconds: engine.state.currentTimeMilliseconds + 2_000 });
    return new TextDecoder().decode(engine.receiveTcp(socket) ?? new Uint8Array());
  });
}

describe('the web server', () => {
  it('answers 400 and 501 and stays connected, where Java closes the connection', () => {
    const engine = startedEngine(network(files({ '/webserver/index.html': 'Start' })));
    expect(ask(engine, 'HALLO', 'GET', 'GET /')).toEqual(['HTTP/1.1 501 Not Implemented\n', 'HTTP/1.1 400 Bad Request\n', 'HTTP/1.1 200 OK\nContent-type: text/html\n\nStart']);
  });

  it('serves nothing outside its document root (Java serves any file of the host), and no folder', () => {
    const engine = startedEngine(network(files({ '/geheim.txt': 'geheim', '/webserver/ordner/a.txt': 'a' })));
    expect(ask(engine, 'GET /../geheim.txt HTTP/1.1', 'GET /ordner/../../geheim.txt HTTP/1.1', 'GET /ordner HTTP/1.1', 'GET /ordner/./a.txt?x HTTP/1.1')).toEqual([
      'HTTP/1.1 404 Not Found\n',
      'HTTP/1.1 404 Not Found\n',
      'HTTP/1.1 404 Not Found\n',
      'HTTP/1.1 200 OK\nContent-type: text/plain\n\na',
    ]);
  });

  it('names the content by the file name: htm, bmp, gif, jpg; jpeg is plain text, as in Java', () => {
    const fileSystem = files({ '/webserver/a.HTM': 'a' });
    const image = new Uint8Array([1, 2, 3, 4]);
    for (const name of ['b.bmp', 'c.gif', 'd.jpg', 'e.jpeg']) fileSystem.writeImageFile(`/webserver/${name}`, image, 'image/png');
    fileSystem.writeBinaryFile('/webserver/f.bin', image);
    const engine = startedEngine(network(fileSystem));
    const types = ask(engine, ...['a.HTM', 'b.bmp', 'c.gif', 'd.jpg', 'e.jpeg', 'f.bin'].map((name) => `GET /${name} HTTP/1.1`)).map(
      (answer) => answer.split('\n')[1],
    );
    expect(types).toEqual(['Content-type: text/html', 'Content-type: image/bmp', 'Content-type: image/gif', 'Content-type: image/jpg', 'Content-type: text/plain', 'Content-type: text/plain']);
    expect(ask(engine, 'GET /f.bin HTTP/1.1')[0]!.endsWith(`\n\n${javaBase64(image)}`)).toBe(true);
  });

  it('serves by host name only from the first five rows of www.conf/vhosts, ignoring case, and from its configuration', () => {
    const vhosts = Array.from({ length: 6 }, (_, index) => `h${index}.de\nv${index}`).join('\n');
    const entries = Object.fromEntries(Array.from({ length: 6 }, (_, index) => [`/webserver/v${index}/index.html`, `V${index}`]));
    const engine = startedEngine(network(files({ ...entries, '/webserver/index.html': 'Start', '/www.conf/vhosts': vhosts })));
    const pages = ask(engine, 'GET / HTTP/1.1\nHost: H4.DE', 'GET / HTTP/1.1\nHost: h5.de', 'GET / HTTP/1.1').map((answer) => answer.split('\n\n')[1]);
    expect(pages).toEqual(['V4', 'Start', 'Start']);

    // Without the file, the table is empty: the configuration's switch alone serves the root.
    const plain = startedEngine(
      network(files({ '/webserver/index.html': 'Start' }), {
        webServersByNodeId: new Map([[SERVER, { port: 80, documentRoot: '/webserver', virtualHosts: true, isActive: true }]]),
      }),
    );
    expect(ask(plain, 'GET / HTTP/1.1\nHost: h0.de')[0]).toBe('HTTP/1.1 200 OK\nContent-type: text/html\n\nStart');
  });

  it('serves nothing without files', () => {
    const engine = startedEngine({ ...network(new VirtualFileSystem()), fileSystemsByNodeId: new Map() });
    expect(ask(engine, 'GET / HTTP/1.1')).toEqual(['HTTP/1.1 404 Not Found\n']);
  });
});

describe('the web browser', () => {
  it('keeps the page and its images, and goes to the last host for a link without one', () => {
    const fileSystem = files({ '/webserver/index.html': '<img src="a.png"><img src="b.png">', '/webserver/seite.html': 'Seite' });
    fileSystem.writeImageFile('/webserver/a.png', new Uint8Array([9, 8, 7]), 'image/png');
    const engine = startedEngine(network(fileSystem));
    const browser = engine.webBrowser(CLIENT)!;
    expect(browser.open('10.0.0.1')).toBe(true);
    engine.handle({ type: 'advance', toMilliseconds: 10_000 });
    expect(browser.page).toMatchObject({ statusCode: 200, body: '<img src="a.png"><img src="b.png">' });
    expect([...browser.page!.images]).toEqual([['a.png', new Uint8Array([9, 8, 7])]]);
    expect(browser.log.all.filter((line) => line.kind === 'image').map((line) => line.kind === 'image' && line.statusCode)).toEqual([200, 404]);

    browser.load('', '/seite.html');
    engine.handle({ type: 'advance', toMilliseconds: 20_000 });
    expect(browser.host).toBe('10.0.0.1');
    expect(browser.page).toMatchObject({ statusCode: 200, body: 'Seite' });
    expect(browser.page!.images.size).toBe(0);
  });

  it('fetches images only for an HTML page', () => {
    const engine = startedEngine(network(files({ '/webserver/text.txt': '<img src="a.png">' })));
    const browser = engine.webBrowser(CLIENT)!;
    browser.open('10.0.0.1/text.txt');
    engine.handle({ type: 'advance', toMilliseconds: 10_000 });
    expect(browser.log.all.map((line) => line.kind)).toEqual(['page']);
  });

  it('does nothing for what is no address', () => {
    const engine = startedEngine(network(files({})));
    expect(engine.webBrowser(CLIENT)!.open('kein host:80')).toBe(false);
    engine.handle({ type: 'advance', toMilliseconds: 5_000 });
    expect(engine.webBrowser(CLIENT)!.log.all).toEqual([]);
    expect(engine.capture.frames(uuid(0x3012))).toEqual([]);
  });

  it('shows "server not reachable" when the server closes without an answer (Java shows nothing)', () => {
    const engine = startedEngine(network(files({}), { webServersByNodeId: new Map() }));
    const listener = engine.openTcpServerSocket(SERVER, 80)!;
    const browser = engine.webBrowser(CLIENT)!;
    browser.open('10.0.0.1');
    for (let time = 100; time < 20_000; time += 100) {
      engine.handle({ type: 'advance', toMilliseconds: time });
      const accepted = engine.state.tcpAcceptedSocketIdsByListenerId.get(listener)?.[0];
      if (accepted !== undefined && engine.state.socketsById.get(accepted)?.tcpState === 'ESTABLISHED') engine.closeTcpSocket(accepted);
    }
    expect(browser.log.all.map((line) => line.kind)).toEqual(['unreachable']);
  });
});