export interface UserGroup {
  Id?: number;
  Name?: string;
}

export interface SyncUser {
  Id: number;
  Number: string;
  FirstName?: string;
  LastName?: string;
  PrimaryGroupId?: number;
  Groups?: UserGroup[];
  Blfs?: string;
  Phones?: Array<{
    TemplateName?: string;
    Name?: string;
  }>;
}

const QUEUE_EXTENSION_MIN = 800;

export const ALWAYS_INCLUDE_EXTENSIONS = ["100"] as const;

export interface ColleagueRef {
  id: number;
  number: string;
  firstName: string;
  lastName: string;
}

export function splitPeerName(name: string | undefined): { firstName: string; lastName: string } {
  const parts = (name ?? "").trim().split(/\s+/).filter(Boolean);
  if (parts.length === 0) {
    return { firstName: "", lastName: "" };
  }
  if (parts.length === 1) {
    return { firstName: parts[0], lastName: "" };
  }
  return { firstName: parts.slice(0, -1).join(" "), lastName: parts[parts.length - 1] };
}

export function addAlwaysIncludedColleagues(
  colleagues: ColleagueRef[],
  extras: ColleagueRef[]
): ColleagueRef[] {
  const next = [...colleagues];
  for (const extra of extras) {
    if (!next.some((c) => c.number === extra.number)) {
      next.push(extra);
    }
  }
  return next;
}

export function isEligibleColleague(user: SyncUser): boolean {
  if (!/^\d+$/.test(user.Number)) {
    return false;
  }
  if (Number.parseInt(user.Number, 10) >= QUEUE_EXTENSION_MIN) {
    return false;
  }
  const first = (user.FirstName ?? "").trim();
  const last = (user.LastName ?? "").trim();
  if (!first && !last) {
    return false;
  }
  const full = `${first} ${last}`.trim().toLowerCase();
  if (full === "voicemail") {
    return false;
  }
  return true;
}

export function primaryDepartmentName(user: SyncUser): string | undefined {
  const groups = user.Groups ?? [];
  const named = groups.find((g) => (g.Name ?? "").toUpperCase() !== "DEFAULT" && (g.Name ?? "").trim() !== "");
  if (named?.Name) {
    return named.Name;
  }
  return undefined;
}

export function groupUsersByDepartment(users: SyncUser[]): Map<string, SyncUser[]> {
  const byDept = new Map<string, SyncUser[]>();
  for (const user of users) {
    const dept = primaryDepartmentName(user);
    if (!dept) {
      continue;
    }
    const list = byDept.get(dept) ?? [];
    list.push(user);
    byDept.set(dept, list);
  }
  return byDept;
}