frontend/src/engine/speech.ts

import type { EventDef, FairyState, Rating, Rng, StyleTag, Taste, Tier, Utterance } from "./types";
import { clamp01, pick } from "./util";

export const STYLE_TAGS: Record<Tier, StyleTag[]> = {
  plain: ["useful", "terse"],
  playful: ["useful", "warm"],
  mythic: ["theatrical", "warm"],
};

const SIDE_QUESTS = [
  "Pay me in a snack and I'll watch it for you.",
  "I left a tiny ✦ on it so I can find it again.",
  "I also rearranged one desktop icon. You'll never know which.",
] as const;

/** Pick the voice tier the taste vector + fairy state favor, with a little caprice. */
export function speak(ev: EventDef, fs: FairyState, taste: Taste, rng: Rng = Math.random): Utterance {
  const tiers = Object.keys(ev.lines) as Tier[];
  let best: Tier = tiers[0];
  let bestW = -1e9;
  for (const tier of tiers) {
    const tags = STYLE_TAGS[tier];
    let w = tags.reduce((a, t) => a + (taste[t] ?? 0.5), 0);
    if (tier === "mythic") w += (fs.mischief - 50) / 90; // mischief loves drama
    if (tier === "plain") w += (fs.protectiveness - 50) / 140;
    w += rng() * 0.5; // a little caprice
    if (w > bestW) {
      bestW = w;
      best = tier;
    }
  }
  let text = ev.lines[best];
  // high mischief sometimes tacks on a harmless side-quest
  if (fs.mischief > 70 && rng() < 0.4) text += ` ${pick(SIDE_QUESTS, rng)}`;
  return { text, tier: best, tags: STYLE_TAGS[best] };
}

/** A rating nudges taste toward / away from the tags that were used. */
export function learn(taste: Taste, tags: StyleTag[], rating: Rating): Taste {
  const t = { ...taste };
  const step = 0.08;
  if (rating === "helpful") {
    for (const g of tags) t[g] = clamp01(t[g] + step);
    t.useful = clamp01(t.useful + step);
  }
  if (rating === "annoying") {
    for (const g of tags) t[g] = clamp01(t[g] - step);
    t.theatrical = clamp01(t.theatrical - step / 2);
  }
  if (rating === "cute") {
    t.theatrical = clamp01(t.theatrical + step);
    t.warm = clamp01(t.warm + step / 2);
    t.useful = clamp01(t.useful - step / 2);
  }
  return t;
}