// Kiitos AI (client side) — a thin, skill-aware wrapper over the server engine's
// move chooser. The heavy dictionary work (prefix search, word finding) lives in
// server/words/kiitosEngine.js so the full ENABLE list never ships to the browser;
// this module just asks for a move and paces it so turns feel deliberate.

import { api } from '../../services/api.js';

// Returns one of:
//   { type:'play', letter, forced:true }       — mandatory next letter
//   { type:'deviate', letter, prefix, word }    — repurpose / start a word
//   { type:'pass' }                             — no legal move
export async function chooseAIMove({ hand, built, targetWord, minLen, skill, allowPrepend, superKiitos }) {
  try {
    return await api.post('/words/kiitos/ai-move', {
      hand, built, targetWord, minLen, skill, allowPrepend, superKiitos,
    });
  } catch (err) {
    console.error('[kiitos] ai-move failed:', err);
    return { type: 'pass' };
  }
}

// A short think time so the AI doesn't snap instantly. Stronger players "decide"
// a touch faster; everyone gets a little jitter.
export function thinkDelay(skill = 3) {
  const k = Math.max(1, Math.min(5, skill | 0));
  return 420 + (5 - k) * 90 + Math.random() * 520;
}