// The pages of routers and home routers as Java FILIUS serves them.
// tools/java-oracle's RouterWebRun let a host's browser ask a router's or
// home router's web server for its index page, its routing table and its
// firewall log (routerweb-java-<story>.java.json). The engine plays the same
// stories: each card's frames must come in the same order, with the same
// content and rows, at about the same time; the server's lines and the
// browser's pages likewise. The pages are Java's German ones.
//
// The router's server switches itself on when the simulation starts (Java
// writes so into its window): lines from before the story's first call are
// not compared. Java's router server sometimes never listens (setAktiv wakes
// its thread only when it already waits), and takes no initial sequence
// number then; the engine's always listens: sequence numbers are compared
// below the millions. The settings page (konfig) changes the firewall at run
// time: a ping passes once "drop ICMP" is saved off; a rule moved above the
// one that accepts the browser shuts it out.

import { readFileSync } from 'node:fs';
import { dirname, join } from 'node:path';
import { fileURLToPath } from 'node:url';
import { describe, expect, it } from 'vitest';
import type { LogLine, NetworkRuntimeEngine } from '../src/index.js';
import { expectSameCaptures, GAP_TOLERANCE_MILLISECONDS, watchedEngine, withClientPortText, type JavaFrame, type JavaTables } from './javaRun.js';
import { browserText, isPolled, POLL_MILLISECONDS, serverText } from './programLines.js';
import { snapshotOf, type Scenario } from './scenario.js';

const scenarioDirectory = join(dirname(fileURLToPath(import.meta.url)), 'scenarios');

const id = (suffix: number) => `00000000-0000-0000-0000-${String(suffix).padStart(12, '0')}`;

type Program = 'server' | 'browser';

interface JavaRun extends JavaTables {
  frames: Record<string, JavaFrame[]>;
  events: [number, string, string][];
}

interface Story {
  readonly scenario: string;
  readonly browser: string;
  readonly router: string;
  readonly acts: readonly [number, (engine: NetworkRuntimeEngine, browser: string) => void][];
}

const open =
  (typed: string) =>
  (engine: NetworkRuntimeEngine, browser: string): void => {
    engine.webBrowser(browser)!.open(typed);
  };

const post =
  (typed: string, data: string) =>
  (engine: NetworkRuntimeEngine, browser: string): void => {
    engine.webBrowser(browser)!.open(typed, data);
  };

const ping = (engine: NetworkRuntimeEngine, browser: string): void => {
  engine.sendIcmpEcho(browser, '20.0.0.2', { sequenceNumber: 1 });
};

/** The form as Java's browser window posts it: every field, then the button pressed. */
const FORM = {
  saveWithoutIcmp: 'firewallActivate=1&onlySYN=1&btnSave=speichern&defaultPolicy=accept&srcIP=&srcMask=&destIP=&destMask=&protocol=*&port=&action=drop',
  addTcpDrop: 'firewallActivate=1&dropICMP=1&onlySYN=1&defaultPolicy=accept&srcIP=&srcMask=&destIP=&destMask=&protocol=TCP&port=80&action=drop&addrule=hinzuf%C3%BCgen',
  moveSecondUp: 'firewallActivate=1&dropICMP=1&onlySYN=1&defaultPolicy=accept&radioRule=2&moveup=rauf&srcIP=&srcMask=&destIP=&destMask=&protocol=*&port=&action=drop',
};

const STORIES: Record<string, Story> = {
  routerIndex: { scenario: 'router-web', browser: id(301), router: id(302), acts: [[500, open('10.0.0.1')]] },
  routerRoutes: { scenario: 'router-web', browser: id(301), router: id(302), acts: [[500, open('10.0.0.1/routes')]] },
  routerKonfig: { scenario: 'router-web', browser: id(301), router: id(302), acts: [[500, open('10.0.0.1/konfig')]] },
  konfigIcmp: {
    scenario: 'router-web',
    browser: id(301),
    router: id(302),
    acts: [
      [500, ping],
      [3500, post('10.0.0.1/konfig', FORM.saveWithoutIcmp)],
      [7000, ping],
    ],
  },
  konfigBlock: {
    scenario: 'router-web',
    browser: id(301),
    router: id(302),
    acts: [
      [500, post('10.0.0.1/konfig', FORM.addTcpDrop)],
      [4000, post('10.0.0.1/konfig', FORM.moveSecondUp)],
      [8000, open('10.0.0.1')],
    ],
  },
  routerLog: {
    scenario: 'router-web',
    browser: id(301),
    router: id(302),
    acts: [
      [500, ping],
      [3500, open('10.0.0.1')],
      [7000, open('10.0.0.1/log')],
    ],
  },
  gatewayIndex: {
    scenario: 'nat-home',
    browser: id(501),
    router: id(502),
    acts: [
      [500, open('192.168.0.1')],
      [4000, open('192.168.0.1/routes')],
    ],
  },
  gatewayFromWan: { scenario: 'nat-home', browser: id(504), router: id(502), acts: [[500, open('42.0.0.10')]] },
  ripRoutes: { scenario: 'rip-chain', browser: id(401), router: id(402), acts: [[40_000, open('10.0.1.1/routes')]] },
};

/** Sequence numbers below the millions: which socket drew which initial number differs (see above). */
const withoutInitialNumbers = (text: string) =>
  withClientPortText(text)
    .replace(/(seq|ack)=(\d+)/g, (_, name: string, value: string) => `${name}=${Number(value) % 1_000_000}`)
    .replace(/(SEQ|ACK): \d+\.(\d{3}\.\d{3})/g, '$1: n.$2');

/** Java's wait for a SYN's answer (TCPSocket: three times 2.75 s, its timeout here). */
const JAVA_TIMEOUT_MILLISECONDS = 3 * 2_750;

/**
 * Where Java errs: its run corrected, as Java means it. routerLog: the
 * German log page closes its title with </titel> (sw_firewallweblog_msg1);
 * the engine writes </title>. konfigBlock: the browser's SYN, dropped by the
 * firewall, goes once in Java, not three times (webJava.test.ts, noServer);
 * the page "server not reachable" comes two attempts later in the engine.
 */
const JAVA_BUGS: Record<string, (java: JavaRun) => JavaRun> = {
  konfigBlock: (java) => ({
    ...java,
    events: java.events.map(([time, who, text]) => (who === 'browser' && text.startsWith('page 0') ? [time + 2 * JAVA_TIMEOUT_MILLISECONDS, who, text] : [time, who, text])),
  }),
  routerLog: (java) => {
    const fixed = (text: string | null) => text?.replace('</titel>', '</title>') ?? null;
    const rows = (byCard: Record<string, (string | null)[][]> | undefined) =>
      Object.fromEntries(Object.entries(byCard ?? {}).map(([card, cardRows]) => [card, cardRows.map((row) => row.map(fixed))]));
    return { ...java, events: java.events.map(([time, who, text]) => [time, who, fixed(text)!]), rows: rows(java.rows), layeredRows: rows(java.layeredRows) };
  },
};

/**
 * ripRoutes: how long a learned route has left. Java's routers start one
 * after the other and draw their beacons' pauses in another order (rip-chain
 * in ripJava.test.ts: R2 sends three times at the start, not twice); a
 * neighbour's beacon refreshes the route some seconds apart. Compared as a
 * placeholder; the page's other cells exactly.
 */
const PAGE_PLACEHOLDERS: Record<string, (text: string) => string> = {
  ripRoutes: (text) => text.replace(/<td>-?\d+<\/td>(<td>[\d.]+<\/td><td><a )/g, '<td>validity</td>$1'),
};

/** Where the frames are compared only up to a time (Java's). konfigBlock: the engine's second SYN, which Java does not send. */
const UNTIL: Record<string, (java: JavaRun) => number> = {
  konfigBlock: (java) => java.events.find(([, who, text]) => who === 'browser' && text.startsWith('page 0'))![0] - 250,
};

type Lines = Record<Program, [number, string][]>;

function javaLines(java: JavaRun): Lines {
  const lines: Lines = { server: [], browser: [] };
  const firstCall = Math.min(...java.events.filter(([, , text]) => text.startsWith('call ')).map(([time]) => time));
  for (const [time, program, text] of java.events) {
    if (program !== 'server' && program !== 'browser') continue;
    if (time < firstCall || text === 'null' || text.startsWith('call ')) continue;
    const page = /^page (\d+) (\S+)\n/.exec(text);
    lines[program].push([time, withClientPortText(page !== null && page[1] !== '200' ? `page ${page[1]} ${page[2]}` : text)]);
  }
  return lines;
}

function engineLines(engine: NetworkRuntimeEngine, story: Story, firstCall: number): Lines {
  const lines = <E>(log: readonly LogLine<E>[], text: (entry: E) => string | undefined): [number, string][] =>
    log.flatMap((line) => {
      const each = line.timeMilliseconds < firstCall ? undefined : text(line);
      return each === undefined ? [] : [[line.timeMilliseconds, withClientPortText(each)] as [number, string]];
    });
  return {
    server: lines(engine.webServer(story.router)!.log.all, serverText),
    browser: lines(engine.webBrowser(story.browser)!.log.all, browserText),
  };
}

describe('the pages of routers and home routers as Java FILIUS serves them', () => {
  it('corrects Java only where it errs, and puts in placeholders only where they change something', () => {
    for (const [name, correct] of Object.entries(JAVA_BUGS)) {
      const java = JSON.parse(readFileSync(join(scenarioDirectory, `routerweb-java-${name}.java.json`), 'utf8')) as JavaRun;
      expect(JSON.stringify(correct(java)), name).not.toBe(JSON.stringify(java));
    }
    for (const [name, placeholders] of Object.entries(PAGE_PLACEHOLDERS)) {
      const text = readFileSync(join(scenarioDirectory, `routerweb-java-${name}.java.json`), 'utf8');
      expect(placeholders(text), name).not.toBe(text);
    }
  });

  for (const [name, story] of Object.entries(STORIES)) {
    it(name, () => {
      const measured = JSON.parse(readFileSync(join(scenarioDirectory, `routerweb-java-${name}.java.json`), 'utf8')) as JavaRun;
      const java = JAVA_BUGS[name]?.(measured) ?? measured;
      const placeholders = PAGE_PLACEHOLDERS[name] ?? ((text: string) => text);
      const scenario = JSON.parse(readFileSync(join(scenarioDirectory, `${story.scenario}.scenario.json`), 'utf8')) as Scenario;
      const snapshot = { ...snapshotOf(scenario), webBrowserNodeIds: new Set([story.browser]) };
      const { engine } = watchedEngine(scenario, snapshot);
      for (const [time, act] of story.acts) {
        engine.handle({ type: 'advance', toMilliseconds: time });
        act(engine, story.browser);
      }
      engine.handle({ type: 'advance', toMilliseconds: Math.max(...java.events.map(([time]) => time)) + 5_000 });

      const firstCall = story.acts[0]![0];
      // Before the story, only what the network does by itself (RIP); compared from the first call.
      expectSameCaptures(engine, scenario, java.frames, {
        text: withoutInitialNumbers,
        cell: (text) => placeholders(withoutInitialNumbers(text)),
        tables: java,
        from: firstCall,
        until: UNTIL[name]?.(measured),
        starts: { java: 0, engine: 0 },
      });

      const withPlaceholders = (lines: Lines): Lines => ({
        server: lines.server.map(([time, text]) => [time, placeholders(text)]),
        browser: lines.browser.map(([time, text]) => [time, placeholders(text)]),
      });
      const expected = withPlaceholders(javaLines(java));
      const actual = withPlaceholders(engineLines(engine, story, firstCall));
      for (const program of ['server', 'browser'] as const) {
        expect(actual[program].map(([, text]) => text), `${program}'s lines`).toEqual(expected[program].map(([, text]) => text));
        for (const [index, [javaTime, text]] of expected[program].entries()) {
          const late = javaTime - actual[program][index]![0];
          const most = (isPolled(text) ? POLL_MILLISECONDS : 0) + GAP_TOLERANCE_MILLISECONDS;
          expect(late, `${program}'s line ${JSON.stringify(text.slice(0, 60))}`).toBeGreaterThanOrEqual(-GAP_TOLERANCE_MILLISECONDS);
          expect(late, `${program}'s line ${JSON.stringify(text.slice(0, 60))}`).toBeLessThanOrEqual(most);
        }
      }
    });
  }
});