// Indicators and economy variables move toward a target each day:
//   target = start value + sum of weighted deviations from the start state + active biases
// Because every term is a deviation from the scenario start, the start is an equilibrium.

import { IND_IDS, VAR_IDS, clamp } from "./state.js";
import { biasFor } from "./modifiers.js";
import { nextNoise } from "./rng.js";

function computeTarget(def, base, group, key, state, devs, bal) {
  let t = base;
  const gain = group === "ind" ? bal.gain ?? 1 : 1;
  for (const [id, w] of Object.entries(def.sectors ?? {})) {
    t += gain * w * (state.sectors[id].quality - state.ref.sectors[id]);
  }
  // Going big pays off: extra weight for quality above `from` (excess) or below it (short).
  for (const [id, [from, w]] of Object.entries(def.excess ?? {})) t += w * Math.max(0, state.sectors[id].quality - from);
  for (const [id, [from, w]] of Object.entries(def.short ?? {})) t -= w * Math.max(0, from - state.sectors[id].quality);
  for (const [k, w] of Object.entries(def.world ?? {})) t += w * state.world[k];
  if (def.drift) t += ((def.drift * (bal.driftScale ?? 1)) * state.day) / 365;
  for (const [id, w] of Object.entries(def.alloc ?? {})) {
    const s = state.sectors[id];
    t += w * (s.alloc / s.need - state.ref.ratio[id]);
  }
  for (const [k, w] of Object.entries(def.econ ?? {})) {
    t += w * (devs[k] - state.ref.dev[k]);
  }
  for (const [k, w] of Object.entries(def.ind ?? {})) {
    t += w * (state.indicators[k] - state.ref.ind[k]);
  }
  return t + biasFor(state, group, key);
}

export function stepVars(state, bal, devs) {
  const next = {};
  for (const id of VAR_IDS) {
    const def = bal.vars[id];
    const target = computeTarget(def, state.ref.vars[id], "var", id, state, devs, bal);
    const v = state.economy[id];
    next[id] = clamp(v + (target - v) / def.tau + nextNoise(state, def.noise), def.min, def.max);
  }
  Object.assign(state.economy, next);
}

export function stepIndicators(state, bal, devs) {
  const next = {};
  for (const id of IND_IDS) {
    const def = bal.indicators[id];
    const target = computeTarget(def, state.ref.ind[id], "ind", id, state, devs, bal);
    const v = state.indicators[id];
    next[id] = clamp(v + (target - v) / def.tau + nextNoise(state, def.noise ?? bal.noise.indicator), 0, 100);
  }
  Object.assign(state.indicators, next);
}