guts/web/js/combat/index.js

// combat/index.js (Lane B) — the createCombat factory. Composes enemies + weapons + hazards
// + pickups and feeds them Lane C's level events. All the wiring, none of the behaviour.
//
// Update order inside a frame is load-bearing:
//   boot: player.update(dt)  ->  combat.update(dt)
//   here: enemies.update(dt) ->  weapons.update(dt) -> hazards.update(dt) -> pickups.update(dt)
// Enemies move first so weapons hit-test against this frame's positions, not last frame's.
// Hazards after weapons so a torpedo fired THIS frame can neutralize a surge THIS frame
// (weapons emits level:neutralize on detonation; hazards listens).

import { createEnemies } from './enemies.js';
import { createWeapons } from './weapons.js';
import { createHazards } from './hazards.js';
import { createPickups } from './pickups.js';
import { createBoss } from './boss.js';
import { getEnemy } from '../levels/enemies.js';

export function createCombat({ scene, world, bus, rng, flags = {}, assets = null, player }) {
  const enemies = createEnemies({ scene, world, bus, rng, assets, flags });
  const weapons = createWeapons({ scene, world, bus, rng, player, targets: enemies });
  const hazards = createHazards({ scene, world, bus, rng, player });
  const pickups = createPickups({ scene, world, bus, rng, player, weapons });
  // Bosses are a SCHEDULE over the enemy pool, not a parallel entity system — see boss.js.
  const boss = createBoss({ bus, rng, player, enemies, flags, getKarma: () => karma });

  enemies.setBlastFx((pos, size, dur) => weapons.spawnBlast(pos, size, dur));
  enemies.setOnDeath((e) => weapons.spawnBlast(e.pos, e.radius * 1.6, 0.3));

  const score = { value: 0, kills: 0, samples: 0 };

  // Fan a group of `count` out along s. C's `spread` is the authored span of the group
  // ("count 4 spread 120" = a field, not a wall); without one, a tight default fan keeps
  // a count from stacking at a single arclength.
  const fan = (ev, i) => {
    const n = ev.count ?? 1;
    if (n <= 1) return ev.s ?? 0;
    const span = ev.spread ?? (n - 1) * 3.5;
    return (ev.s ?? 0) + (i / (n - 1)) * span;
  };
  // C authors `theta` as a scalar (whole group) or an array (per-member — "two blooms
  // covering opposite arcs"). Placement is composition, so C's word is law here.
  const thetaFor = (ev, i) =>
    (Array.isArray(ev.theta) ? ev.theta[i % ev.theta.length] : (ev.theta ?? null));

  // Lane C's events arrive on the bus as the player crosses their `s`. Spawns and pickups are
  // consumed here; hazards run their own timeline off world.level.events (they need lookahead
  // for the warn telegraph — see hazards.js header); checkpoints/gates are boot's (the pump
  // owns respawn/complete semantics); unknown types are ignored on purpose so C can add event
  // kinds without breaking combat.
  const offEvent = bus.on('level:event', (ev) => {
    if (!ev) return;
    if (ev.type === 'spawn') {
      // Levels name enemies in fiction ("bolus_chunk"); pools are keyed by archetype
      // ("floater"). levels/enemies.js is the join table (C's catalogue, round-2 task #1).
      const spec = getEnemy(ev.enemy);
      if (!spec) { console.warn(`[combat] spawn "${ev.enemy}" is not in levels/enemies.js — skipped`); return; }
      for (let i = 0; i < (ev.count ?? 1); i++)
        enemies.spawn(spec.archetype, { s: fan(ev, i), theta: thetaFor(ev, i), rho: ev.rho ?? null });
    } else if (ev.type === 'pickup') {
      for (let i = 0; i < (ev.count ?? 1); i++)
        pickups.spawn(ev.kind, { s: fan(ev, i), theta: thetaFor(ev, i), rho: ev.rho ?? null });
    } else if (ev.type === 'biofilm') {
      biofilmGate(ev);
    }
  });

  const offDie = bus.on('enemy:die', (e) => {
    score.value += e.score ?? 0;
    // Allies do not count. This was an unconditional ++, so flora and spent phages — which
    // score 0 precisely because they are not pathogens — still raised the PATHOGENS tally on
    // the pause card and the operative record.
    if (e.foe !== false) score.kills++;
  });

  // pickups.js applies the effect (refill/ammo) and announces; the score lives here so
  // combat:state stays the one scoreboard E reads.
  const offPickup = bus.on('pickup', (e) => {
    score.value += e.score ?? 0;
    score.samples += e.sample ?? 0;
  });

  // BIOME STANDING — the flora reputation loop (V2_IDEAS: "don't shoot the biome, it helps you
  // in level 5"). Tend flora (fly through its aura -> flora:tended) to earn it; shoot flora
  // (flora:harmed) to lose a chunk. At the symbiotic threshold the biome BUDS phage allies near
  // you that hunt your foes — the payoff. A `standing` event feeds a future HUD meter (Lane E).
  // ponytail: one run-scoped float, not a system. Persistence/tiers/L5-gate come when C needs them.
  // Scaled 0..100 so E can meter it honestly: tending fills the bar, a full bar buds an ally
  // and drops it to 50 (the recharge floor), harming flora empties a big chunk. Numbers are a
  // first pass — C/playtest tunes the feel.
  // TWO numbers, because they do two different jobs and conflating them is a bug I shipped once:
  //   standing — a SPENDABLE meter. Fills as you tend, and a full bar is CONSUMED to bud an ally
  //              (dropping to a 50 floor). It is a resource.
  //   karma    — a LEDGER of conduct. Same inputs, but nothing ever spends it. This is what the
  //              Appendix Sovereign and the secret door read, because "how did you treat the
  //              biome across the campaign" must not be answerable by "how recently did you cash
  //              in". With one number, budding an ally at 100 dropped you to 50 and quietly made
  //              the Sovereign's best outcome unreachable.
  let standing = 0, karma = 0, phageBudCd = 0;
  const setStanding = (v) => { standing = Math.max(0, Math.min(100, v)); bus.emit('standing', { value: standing }); };
  const setKarma = (v) => { karma = Math.max(0, Math.min(100, v)); bus.emit('karma', { value: karma }); };
  const offTended = bus.on('flora:tended', (e) => {
    const g = e?.gain ?? 5;
    setStanding(standing + g); setKarma(karma + g); budPhage();
  });
  const offHarmed = bus.on('flora:harmed', () => { setStanding(standing - 35); setKarma(karma - 35); });
  function budPhage() {
    if (standing < 100 || phageBudCd > 0) return;          // a FULL bar buds an ally
    if (enemies.live.filter((e) => e.type === 'phage' && e.alive).length >= 3) return;  // ally cap
    if (enemies.spawn('phage', { s: player.state.s + 8 })) {
      setStanding(50);                            // recharge floor — the next ally is halfway earned
      phageBudCd = 3;                              // seconds between buds (decremented below)
      bus.emit('audio:cue', { name: 'pickup' });   // a friendly chirp when an ally is born
    }
  }

  // biofilm gate — the reputation CASH-OUT (V2_IDEAS: "it helps you in level 5"). Cross one with
  // high BIOME STANDING and the native flora part the biofilm: a wave of phage allies buds and
  // your coat is refilled, then the goodwill is spent. Low standing => it stays sealed and you run
  // the gauntlet raw. Placed as a `biofilm` level event (`need`/`allies`/`coat` optional). Emits
  // `biofilm {opened}` so E can voice it. The L5 payoff, built as a mechanism usable anywhere.
  function biofilmGate(ev) {
    const opened = standing >= (ev.need ?? 60);
    if (opened) {
      for (let i = 0; i < (ev.allies ?? 3); i++) enemies.spawn('phage', { s: player.state.s + 6 + i * 4 });
      player.refill({ coat: ev.coat ?? 40 });
      setStanding(20);                            // spent the goodwill
    }
    bus.emit('biofilm', { opened, s: ev.s });
    bus.emit('audio:cue', { name: opened ? 'gate_pass' : 'gate_hit' });
  }

  function update(dt) {
    if (phageBudCd > 0) phageBudCd -= dt;
    // Before enemies.update: the boss decides this frame's invulnerability, so the window a
    // player shoots into is the one they were just told about rather than one frame stale.
    boss.update(dt);
    enemies.update(dt, player);
    weapons.update(dt);
    hazards.update(dt);
    pickups.update(dt);
    // combat's slice of the HUD state (E reads player:state for the flight half)
    bus.emit('combat:state', {
      heat: weapons.heat, heatMax: weapons.heatMax, overheated: weapons.overheated,
      ammo: weapons.ammo, ammoMax: weapons.ammoMax,
      score: score.value, kills: score.kills, samples: score.samples, enemies: enemies.count,
    });
  }

  return {
    update,
    enemies, weapons, hazards, pickups, boss, score,
    /** BIOME STANDING 0..100 — the spendable meter (E's HUD bar). */
    get standing() { return standing; },
    /** KARMA 0..100 — the unspendable conduct ledger. boot reads it for `secretTo` branches. */
    get karma() { return karma; },
    // Respawn support (boot calls this from its death->checkpoint glue): re-arm hazard
    // timelines at/ahead of the respawn s. Enemies and uncollected pickups persist — the
    // pump never re-fires past events, so nothing double-spawns.
    reset(fromS = 0) { hazards.reset(fromS); boss.reset(); },
    dispose() {
      offEvent(); offDie(); offPickup(); offTended(); offHarmed();
      boss.dispose();
      enemies.dispose(); weapons.dispose(); hazards.dispose(); pickups.dispose();
    },
  };
}