const fs = require('fs');
const path = require('path');
const { getEnv, ORCHESTRATION, INFERENCE_DEFAULTS, RETRIEVAL } = require('@nexusai/shared');

const SETTINGS_PATH = path.join(__dirname, '../../data/settings.json');

const DEFAULTS = {
  recentEpisodeLimit:   ORCHESTRATION.RECENT_EPISODE_LIMIT,
  semanticLimit:        ORCHESTRATION.SEMANTIC_LIMIT,
  scoreThreshold:       ORCHESTRATION.SCORE_THRESHOLD,
  modelsFolderPath:     getEnv('MODELS_MANIFEST_PATH', '/mnt/nexus-models'),
  temperature:          INFERENCE_DEFAULTS.TEMPERATURE,
  repeatPenalty:        INFERENCE_DEFAULTS.REPEAT_PENALTY,
  topP:                 INFERENCE_DEFAULTS.TOP_P,
  topK:                 INFERENCE_DEFAULTS.TOP_K,
  systemPrompt:         ORCHESTRATION.SYSTEM_PROMPT,
  semanticWeight:       RETRIEVAL.SEMANTIC_WEIGHT,
  keywordWeight:        RETRIEVAL.KEYWORD_WEIGHT,
};

function load() {
  try {
    const raw = fs.readFileSync(SETTINGS_PATH, 'utf8');
    return { ...DEFAULTS, ...JSON.parse(raw) };
  } catch {
    return { ...DEFAULTS }; // file doesn't exist yet — use defaults
  }
}

function save(updates) {
  const current = load();
  const next = { ...current, ...updates };
  fs.mkdirSync(path.dirname(SETTINGS_PATH), { recursive: true });
  fs.writeFileSync(SETTINGS_PATH, JSON.stringify(next, null, 2));
  return next;
}

module.exports = { load, save, DEFAULTS };