const DATA_START = 140;
const RECORD_SIZE = 408;
const STAT_KEYS = ["strength", "stamina", "intellect", "wisdom", "agility", "health", "mana"];

/** Players use FixArgTableID = 1; each vocation has two adjacent source records. */
export function vocationGrowth(buffer, classIndex) {
  const recordId = 301000 + classIndex * 2 + 1;
  const offset = DATA_START + (classIndex * 2 + 1) * RECORD_SIZE;
  if (offset + RECORD_SIZE > buffer.length
    || buffer.readInt32LE(offset) !== recordId || buffer.readInt32LE(offset + 4) !== recordId) {
    throw new Error(`Player vocation ${classIndex} record sentinel drifted.`);
  }
  const values = Array.from({ length: 21 }, (_, index) => {
    const value = buffer.readFloatLE(offset + 8 + index * 4);
    if (!Number.isFinite(value)) throw new Error(`Player vocation ${classIndex} has invalid growth.`);
    return Number(value.toFixed(5));
  });
  return Object.fromEntries(STAT_KEYS.map((key, index) => [key, {
    levelOne: values[index],
    flatGrowth: values[index + 7],
    percentGrowth: values[index + 14],
  }]));
}