import { GroupedItem } from './types.js';
import { parseAddress } from './codec.js';

export function groupByDb<T extends { address: string }>(items: T[]): Map<number, GroupedItem<T>[]> {
  const groups = new Map<number, GroupedItem<T>[]>();
  for (const item of items) {
    const addr = parseAddress(item.address);
    let group = groups.get(addr.dbNumber);
    if (!group) { group = []; groups.set(addr.dbNumber, group); }
    group.push({ addr, item });
  }
  return groups;
}

export function byteRange<T>(items: GroupedItem<T>[], getSize: (item: T) => number): { start: number; size: number } {
  let min = Infinity, max = 0;
  for (const { addr, item } of items) {
    const end = addr.byteOffset + getSize(item);
    if (addr.byteOffset < min) min = addr.byteOffset;
    if (end > max) max = end;
  }
  return { start: min, size: max - min };
}