// main.js — the router. 64 hops, one TTL, no way back up except through.

import * as THREE from '../vendor/three.module.js';
import * as A from './audio.js';
import * as In from './input.js';
import * as HUD from './hud.js';
import { Link } from './link.js';
import { World } from './kit.js';
import { lookup as phileLookup, TOTAL as PHILE_TOTAL } from './philes.js';

import coldboot  from './levels/coldboot.js';
import stack     from './levels/stack.js';
import timewait  from './levels/timewait.js';
import war       from './levels/war.js';
import smash     from './levels/smash.js';
import worm      from './levels/worm.js';
import cuckoo    from './levels/cuckoo.js';
import board     from './levels/board.js';
import handshake from './levels/handshake.js';
import copper    from './levels/copper.js';
import bluebox   from './levels/bluebox.js';
import climb     from './levels/climb.js';
import root      from './levels/root.js';

export const ORDER = [
  coldboot, stack, timewait, war, smash, worm,
  cuckoo, board, handshake, copper, bluebox, climb, root,
];
const BY_ID = Object.fromEntries(ORDER.map(l => [l.id, l]));

const canvas = document.getElementById('gl');
const termCanvas = document.getElementById('term');
const renderer = new THREE.WebGLRenderer({ canvas, antialias: false, powerPreference: 'high-performance' });
renderer.setClearColor(0x000000, 1);
renderer.autoClear = true;

const link = new Link(renderer);
In.attach(canvas);
HUD.boot();

// ───────────────────────────────────────────────────────────── game state

export const game = {
  ttl: 64,
  hop: 1,
  level: null,
  flags: Object.create(null),   // what you learned, what you carry, who you met
  philes: new Set(),            // the collectibles. the writing lives here.
  cargo: [],                    // BBS files. affects MTU.
  mtu: 1500,
  deaths: 0,
  reached: new Set(['coldboot']),
  paused: false,
  time: 0,
};
// dev handle. HS.run(n) drives n frames by hand when rAF is asleep.
window.HS = {
  game, link, A, In, HUD, THREE,
  goto: (id) => goto(id),
  run(n = 60, dt = 1 / 60) { for (let i = 0; i < n; i++) step(dt); },
};

function refreshHud() {
  HUD.status({
    ttl: game.ttl, hop: game.hop, hops: 64, link: link.label,
    extra: game.cargo.length ? `MTU ${game.mtu}  ·  ${game.cargo.length} file${game.cargo.length > 1 ? 's' : ''}` : '',
  });
}

// How many pieces you arrive in. Two files is free; after that the network starts
// charging you for the privilege of being interesting.
export function fragments() {
  game.mtu = Math.max(400, 1500 - game.cargo.length * 180);
  if (game.cargo.length <= 2) return 1;
  return 1 + Math.ceil((game.cargo.length - 2) / 3);
}
let fragNote = null;

// TTL only ever goes down. There is no item for this.
export function spendTTL(n = 1, why = '') {
  game.ttl -= n;
  refreshHud();
  if (why) HUD.say(`<i>${why}</i> &nbsp;−${n} TTL`, 1800);
  if (game.ttl <= 0) expire();
  return game.ttl;
}

let expiring = false;
async function expire() {
  if (expiring) return;
  expiring = true;
  game.deaths++;
  A.noCarrier();
  link.glitch = 0.9;
  await HUD.flash('NO CARRIER', 'nc', 2400);
  link.glitch = 0;
  // ICMP Time Exceeded is sent to where you came from. It always is.
  HUD.say('icmp time exceeded — in transit', 2600);
  game.ttl = Math.max(12, 65 - game.hop);
  expiring = false;
  await goto(game.level.id, { restart: true });
}
export { expire };

// ────────────────────────────────────────────────────────────── the loop

const ctx = {
  THREE, A, In, HUD, link, game, renderer,
  scene: null, camera: null, world: null, term: null, termCanvas,
  spendTTL,
  refreshHud: () => refreshHud(),
  setBaud(i) { link.setBaud(i); refreshHud(); return link.spec; },
  goto: (id, o) => goto(id, o),
  next: () => {
    const i = ORDER.indexOf(game.level);
    return goto(ORDER[Math.min(ORDER.length - 1, i + 1)].id);
  },
  say: HUD.say, speak: HUD.speak, hint: HUD.hint, card: HUD.card, sleep: HUD.sleep,
  hush: HUD.hush, flash: HUD.flash, expire: () => expire(),
  phile(id, title, body) {
    if (game.philes.has(id)) return false;
    game.philes.add(id);
    const p = phileLookup(id, title, body);
    HUD.say(`<b>phile</b> ${p.title}  <i>[${game.philes.size}/${PHILE_TOTAL}]</i> &nbsp; <k>P</k> to read`, 3000);
    A.blip(1800, 0.05, 0.05); setTimeout(() => A.blip(2400, 0.06, 0.05), 70);
    phileLog.push(p);
    return true;
  },
};
const phileLog = [];
window.HS.philes = phileLog;
window.HS.ctx = ctx;

function disposeScene(s) {
  if (!s) return;
  s.traverse(o => {
    if (o.geometry) o.geometry.dispose();
    const mats = o.material ? (Array.isArray(o.material) ? o.material : [o.material]) : [];
    for (const m of mats) {
      for (const k of ['map', 'alphaMap', 'emissiveMap']) if (m[k] && m[k].dispose && !m[k].__keep) m[k].dispose();
      m.dispose();
    }
  });
}

let switching = false;
export async function goto(id, { restart = false } = {}) {
  if (switching) return;
  switching = true;
  const nextLevel = BY_ID[id];
  if (!nextLevel) { console.warn('no level', id); switching = false; return; }

  HUD.hint('');
  HUD.hush();
  await HUD.veil(1, 420);
  A.stopPad();

  if (game.level && game.level.unmount) { try { await game.level.unmount(ctx); } catch (e) { console.error(e); } }
  In.releaseText(); In.clearRemap(); In.unlock();
  ctx.splitCam = null;
  termCanvas.style.display = 'none';
  disposeScene(ctx.scene);

  ctx.scene = new THREE.Scene();
  ctx.camera = new THREE.PerspectiveCamera(72, link.aspect, 0.05, 4000);
  ctx.world = new World();

  game.level = nextLevel;
  game.reached.add(id);
  if (!restart) game.hop = nextLevel.hop;
  game.ttl = Math.max(1, Math.min(game.ttl, 65 - game.hop));

  // ── MTU. Carry too much and you do not fit down the next hop in one piece.
  // Everything you took off the board is lore, and lore is paid for in distance.
  if (!restart) {
    const frags = fragments();
    if (frags > 1) {
      game.ttl -= (frags - 1);
      fragNote = `<b>fragmented</b> ${game.mtu} byte MTU · ${frags} pieces · −${frags - 1} TTL`;
      if (game.ttl <= 0) { expire(); switching = false; return; }
    } else fragNote = null;
  }
  if (nextLevel.baud !== undefined && nextLevel.baud !== null) link.setBaud(nextLevel.baud);
  link.noTint();
  if (nextLevel.tint) link.tint(nextLevel.tint[0], nextLevel.tint[1]);
  document.body.classList.toggle('ink-dark', nextLevel.ink === 'dark');
  refreshHud();
  HUD.showHud(nextLevel.hud !== false);

  // A level builds its scene synchronously and only then awaits its intro card, so
  // start lifting the veil as soon as mount is under way — otherwise the player
  // stares at a black screen for the length of the card that is playing behind it.
  const mounting = (async () => { try { await nextLevel.mount(ctx); } catch (e) { console.error('mount failed:', id, e); } })();
  HUD.veil(0, 520);
  await mounting;
  refreshHud();
  saveGame();
  if (fragNote) { HUD.say(fragNote, 3600); fragNote = null; }
  switching = false;
}

let last = performance.now();
function frame(now) {
  requestAnimationFrame(frame);
  const dt = Math.min(0.05, (now - last) / 1000);
  last = now;
  step(dt);
}

// One tick, separated from rAF so it can be driven by hand — rAF is throttled to
// zero in a hidden tab, which makes the game look broken when it is only asleep.
export function step(dt) {
  game.time += dt;

  if (In.hit('Escape')) { In.unlock(); if (readerOpen) toggleReader(); }
  if (In.hit('KeyM') && !In.hasTextCapture()) toggleMap();
  if (In.hit('KeyP') && !In.hasTextCapture()) toggleReader();
  if (In.hit('Backquote')) toggleDev();

  if (!game.paused && game.level && game.level.update) {
    try { game.level.update(dt, game.time, ctx); } catch (e) { console.error(e); game.level.update = null; }
  }
  if (ctx.term && termCanvas.style.display !== 'none') ctx.term.draw(game.time);
  if (ctx.scene && ctx.camera) {
    // a level can ask for two viewports by setting ctx.splitCam
    if (ctx.splitCam) link.renderSplit(ctx.scene, ctx.camera, ctx.splitCam, game.time);
    else link.render(ctx.scene, ctx.camera, game.time);
  }
  In.endFrame();
}

addEventListener('resize', () => {
  link.resize();
  if (ctx.camera && ctx.camera.isPerspectiveCamera) { ctx.camera.aspect = link.aspect; ctx.camera.updateProjectionMatrix(); }
  if (ctx.term) ctx.term.resize();
});

// ─────────────────────────────────────────────────── traceroute level select

const mapEl = document.getElementById('map');
let mapOpen = false;
function toggleMap() {
  mapOpen = !mapOpen;
  game.paused = mapOpen;
  mapEl.style.display = mapOpen ? 'flex' : 'none';
  if (mapOpen) {
    In.unlock();
    const rows = ORDER.map((l, i) => {
      const seen = game.reached.has(l.id);
      const here = game.level === l;
      const hopn = String(l.hop).padStart(2, '0');
      const name = seen ? l.title : '* * *';
      const via  = seen ? l.via : '';
      return `<div class="row ${seen ? 'seen' : ''} ${here ? 'here' : ''}" data-id="${l.id}">
        <span class="n">${hopn}</span>
        <span class="nm">${name}</span>
        <span class="via">${via || ''}</span>
        <span class="ms">${seen ? (l.ms || (12 + i * 17) + ' ms') : ''}</span></div>`;
    }).join('');
    const frags = fragments();
    const cargo = game.cargo.length
      ? `<div class="cargo">carrying ${game.cargo.length} · MTU ${game.mtu} · ${frags > 1
          ? `<span class="bad">fragmenting into ${frags}, −${frags - 1} TTL every hop</span>`
          : 'fits in one piece'}<br>` +
        game.cargo.map((f, i) => `<span class="drop" data-c="${i}">${f} ✕</span>`).join(' ') + '</div>'
      : '';
    mapEl.innerHTML = `<div class="trace">
      <div class="hdr">traceroute to root (0.0.0.0), 64 hops max, ${game.mtu} byte packets</div>
      ${rows}
      ${cargo}
      <div class="ftr">TTL ${game.ttl} remaining · ${game.philes.size} philes · ${game.deaths} expiries
      <br><span class="dim">click a reached hop to return · P for philes · M to close</span></div></div>`;
    mapEl.querySelectorAll('.row.seen').forEach(r => r.addEventListener('click', () => {
      const id = r.dataset.id;
      toggleMap();
      goto(id);
    }));
    // you can put something down. that is the whole trade.
    mapEl.querySelectorAll('.drop').forEach(el => el.addEventListener('click', () => {
      game.cargo.splice(+el.dataset.c, 1);
      fragments(); refreshHud(); saveGame();
      toggleMap(); toggleMap();
    }));
  }
}

// ────────────────────────────────────────────────────── the phile reader
// You spend the game collecting text files. There has to be somewhere to read them.

const readerEl = document.getElementById('reader');
let readerOpen = false, readerAt = 0;
function toggleReader() {
  readerOpen = !readerOpen;
  game.paused = readerOpen;
  readerEl.style.display = readerOpen ? 'flex' : 'none';
  if (readerOpen) { In.unlock(); drawReader(); }
}
function drawReader() {
  if (!phileLog.length) {
    readerEl.innerHTML = `<div class="rd"><div class="hdr">philes  0/${PHILE_TOTAL}</div>
      <div class="empty">you have not picked anything up yet.<br><br>
      they are lying around. nothing tells you where.</div>
      <div class="ftr"><span class="dim">P to close</span></div></div>`;
    return;
  }
  readerAt = Math.max(0, Math.min(phileLog.length - 1, readerAt));
  const p = phileLog[readerAt];
  const list = phileLog.map((q, i) =>
    `<div class="it ${i === readerAt ? 'on' : ''}" data-i="${i}">${q.title}</div>`).join('');
  readerEl.innerHTML = `<div class="rd">
    <div class="hdr">philes  ${phileLog.length}/${PHILE_TOTAL}</div>
    <div class="cols">
      <div class="list">${list}</div>
      <div class="body"><h2>${p.title}</h2>${p.from ? `<div class="from">${p.from}</div>` : ''}<pre>${p.body || '(no text)'}</pre></div>
    </div>
    <div class="ftr"><span class="dim">click a title · P to close</span></div></div>`;
  readerEl.querySelectorAll('.it').forEach(el =>
    el.addEventListener('click', () => { readerAt = +el.dataset.i; drawReader(); }));
}

// ─────────────────────────────────────────────── ESTABLISHED — the save
// You do not save. You connect. Sitting still long enough to complete a handshake
// with the world is your checkpoint — which in practice means every hop, because
// arriving somewhere is the only moment the state is worth anything.

const SAVE_KEY = 'handshake.save.v1';
function saveGame() {
  try {
    localStorage.setItem(SAVE_KEY, JSON.stringify({
      level: game.level ? game.level.id : 'coldboot',
      ttl: game.ttl, hop: game.hop, baud: link.index,
      philes: [...game.philes], phileLog,
      cargo: game.cargo, mtu: game.mtu, flags: game.flags, deaths: game.deaths,
    }));
  } catch (e) { /* private browsing, a full disk, somebody's kiosk. not worth dying over. */ }
}
export function loadSave() {
  try { return JSON.parse(localStorage.getItem(SAVE_KEY) || 'null'); } catch (e) { return null; }
}
function applySave(s) {
  game.ttl = s.ttl; game.hop = s.hop;
  game.philes = new Set(s.philes || []);
  phileLog.length = 0; (s.phileLog || []).forEach(p => phileLog.push(p));
  game.cargo = s.cargo || []; game.mtu = s.mtu ?? 1500;
  game.flags = s.flags || Object.create(null);
  game.deaths = s.deaths || 0;
  link.setBaud(s.baud ?? 6);
  ORDER.forEach(l => { if (l.hop <= s.hop) game.reached.add(l.id); });
}
export function wipeSave() { try { localStorage.removeItem(SAVE_KEY); } catch (e) {} }

// ─────────────────────────────────────────────────────────────── dev

const devEl = document.getElementById('dev');
let devOpen = false;
function toggleDev() {
  devOpen = !devOpen;
  devEl.style.display = devOpen ? 'block' : 'none';
  if (devOpen) {
    devEl.innerHTML = ORDER.map((l, i) =>
      `<button data-id="${l.id}">${String(i + 1).padStart(2, '0')} ${l.title}</button>`).join('') +
      `<div class="baud">baud: ${[0,1,2,3,4,5,6].map(b => `<button data-baud="${b}">${b}</button>`).join('')}</div>`;
    devEl.querySelectorAll('[data-id]').forEach(b => b.onclick = () => { toggleDev(); goto(b.dataset.id); });
    devEl.querySelectorAll('[data-baud]').forEach(b => b.onclick = () => { link.setBaud(+b.dataset.baud); refreshHud(); });
  }
}

// ─────────────────────────────────────────────────────────────── boot

const bootEl = document.getElementById('boot');
const save = loadSave();
if (save) {
  const l = ORDER.find(x => x.id === save.level);
  document.getElementById('resume').innerHTML =
    `<b>R</b> — RESUME &nbsp; hop ${String(save.hop).padStart(2, '0')} · ${l ? l.title : save.level} · TTL ${save.ttl} · ${(save.philes || []).length} philes`;
  document.getElementById('resume').style.display = 'block';
}

let started = false;
async function start(resume) {
  if (started) return;
  started = true;
  bootEl.style.display = 'none';
  A.boot(); A.resume();
  requestAnimationFrame(frame);
  if (resume && save) { applySave(save); await goto(save.level, { restart: true }); }
  else { wipeSave(); await goto('coldboot'); }
}
bootEl.addEventListener('click', () => start(false));
addEventListener('keydown', function once(e) {
  if (started) { removeEventListener('keydown', once); return; }
  if (e.key === 'Tab') return;
  removeEventListener('keydown', once);
  start(save && e.key.toLowerCase() === 'r');
});

// carrier detect blinking on the boot screen, because of course
{
  const cd = document.getElementById('cd');
  setInterval(() => { if (cd) cd.style.opacity = cd.style.opacity === '0.15' ? '1' : '0.15'; }, 620);
}