const fs = require('fs');
const path = require('path');

const CONFIG_DIR = path.join(__dirname, '..', 'config');
const SETTINGS_FILE = path.join(CONFIG_DIR, 'admin-settings.json');

const DEFAULT_SETTINGS = {
  scheduleCron: '*/10 7-22 * * *',
  randomDelayMinSeconds: 10,
  randomDelayMaxSeconds: 120,
  initialDelayMinSeconds: 5,
  initialDelayMaxSeconds: 30,
  ignoredSlots: [
    {
      storeId: '51450',
      description: 'TVS'
    }
  ]
};

function ensureDir() {
  if (!fs.existsSync(CONFIG_DIR)) {
    fs.mkdirSync(CONFIG_DIR, { recursive: true });
  }
}

function sanitizeNumber(value, fallback) {
  const num = Number(value);
  if (Number.isFinite(num) && num >= 0) {
    return num;
  }
  return fallback;
}

function sanitizeIgnoredSlots(slots = []) {
  if (!Array.isArray(slots)) {
    return DEFAULT_SETTINGS.ignoredSlots;
  }
  return slots
    .map((slot) => ({
      storeId: slot?.storeId ? String(slot.storeId) : '',
      description: slot?.description ? String(slot.description) : ''
    }))
    .filter((slot) => slot.storeId);
}

function readSettings() {
  ensureDir();
  if (!fs.existsSync(SETTINGS_FILE)) {
    fs.writeFileSync(SETTINGS_FILE, JSON.stringify(DEFAULT_SETTINGS, null, 2));
    return { ...DEFAULT_SETTINGS };
  }

  try {
    const raw = fs.readFileSync(SETTINGS_FILE, 'utf8');
    const parsed = JSON.parse(raw);
    return {
      scheduleCron: parsed.scheduleCron || DEFAULT_SETTINGS.scheduleCron,
      randomDelayMinSeconds: sanitizeNumber(parsed.randomDelayMinSeconds, DEFAULT_SETTINGS.randomDelayMinSeconds),
      randomDelayMaxSeconds: sanitizeNumber(parsed.randomDelayMaxSeconds, DEFAULT_SETTINGS.randomDelayMaxSeconds),
      initialDelayMinSeconds: sanitizeNumber(parsed.initialDelayMinSeconds, DEFAULT_SETTINGS.initialDelayMinSeconds),
      initialDelayMaxSeconds: sanitizeNumber(parsed.initialDelayMaxSeconds, DEFAULT_SETTINGS.initialDelayMaxSeconds),
      ignoredSlots: sanitizeIgnoredSlots(parsed.ignoredSlots)
    };
  } catch (error) {
    console.error('Konnte Admin-Einstellungen nicht lesen:', error.message);
    return { ...DEFAULT_SETTINGS };
  }
}

function writeSettings(patch = {}) {
  const current = readSettings();
  const next = {
    scheduleCron: patch.scheduleCron || current.scheduleCron,
    randomDelayMinSeconds: sanitizeNumber(patch.randomDelayMinSeconds, current.randomDelayMinSeconds),
    randomDelayMaxSeconds: sanitizeNumber(patch.randomDelayMaxSeconds, current.randomDelayMaxSeconds),
    initialDelayMinSeconds: sanitizeNumber(patch.initialDelayMinSeconds, current.initialDelayMinSeconds),
    initialDelayMaxSeconds: sanitizeNumber(patch.initialDelayMaxSeconds, current.initialDelayMaxSeconds),
    ignoredSlots:
      patch.ignoredSlots !== undefined
        ? sanitizeIgnoredSlots(patch.ignoredSlots)
        : current.ignoredSlots
  };

  ensureDir();
  fs.writeFileSync(SETTINGS_FILE, JSON.stringify(next, null, 2));
  return next;
}

module.exports = {
  DEFAULT_SETTINGS,
  readSettings,
  writeSettings
};