import { Collection } from "@discordjs/collection";
import { connectWiseApi } from "../../../constants";
import { runCollector } from "../../collector-client/runCollector";

export interface CWMember {
  id: number;
  identifier: string;
  firstName: string;
  lastName: string;
  officeEmail: string;
  inactiveFlag: boolean;
  _info: Record<string, string>;
}

interface CollectorMemberRecord {
  memberRecId: number;
  memberId: string;
  firstName: string | null;
  lastName: string | null;
  emailAddress: string | null;
  deleteFlag: boolean;
  lastUpdateUtc?: string | null;
  lastUpdate?: string | null;
  _info?: Record<string, string>;
}

const isCollectorMemberRecord = (
  value: unknown,
): value is CollectorMemberRecord => {
  if (!value || typeof value !== "object") {
    return false;
  }

  const candidate = value as Partial<CollectorMemberRecord>;
  return (
    typeof candidate.memberRecId === "number" &&
    typeof candidate.memberId === "string"
  );
};

const normalizeCollectorMember = (
  member: CollectorMemberRecord,
): CWMember => {
  const updatedAt = member.lastUpdateUtc ?? member.lastUpdate ?? "";

  return {
    id: member.memberRecId,
    identifier: member.memberId,
    firstName: member.firstName ?? "",
    lastName: member.lastName ?? "",
    officeEmail: member.emailAddress ?? "",
    inactiveFlag: Boolean(member.deleteFlag),
    _info: member._info ?? { lastUpdated: updatedAt },
  };
};

/**
 * Fetch All CW Members
 *
 * Fetches every member from ConnectWise using pagination and returns them
 * in a Collection keyed by their identifier (e.g. "jroberts").
 *
 * @param opts.conditions - Optional CW conditions string to filter members
 * @returns {Promise<Collection<string, CWMember>>} Collection of CW members keyed by identifier
 */
export const fetchAllCwMembers = async (opts?: {
  conditions?: string;
}): Promise<Collection<string, CWMember>> => {
  if (!opts?.conditions) {
    try {
      const collectorMembers = await runCollector<unknown[]>("fetchMembers");
      if (!Array.isArray(collectorMembers)) {
        throw new Error("Collector payload was not an array");
      }

      const members = new Collection<string, CWMember>();
      for (const member of collectorMembers) {
        if (!isCollectorMemberRecord(member)) {
          continue;
        }

        const normalized = normalizeCollectorMember(member);
        members.set(normalized.identifier, normalized);
      }

      if (members.size > 0) {
        console.log(
          `[fetchAllCwMembers] Using collector data from fetchMembers (${members.size} members)`,
        );
        return members;
      }

      throw new Error("Collector payload did not contain valid member records");
    } catch (err) {
      console.warn(
        `[fetchAllCwMembers] Collector fetchMembers failed, falling back to CW API: ${err instanceof Error ? err.message : String(err)}`,
      );
    }
  }

  const members = new Collection<string, CWMember>();
  const pageSize = 1000;
  const conditionsParam = opts?.conditions
    ? `&conditions=${encodeURIComponent(opts.conditions)}`
    : "";

  const { data: countData } = await connectWiseApi.get(
    `/system/members/count${conditionsParam ? `?${conditionsParam.slice(1)}` : ""}`,
  );
  const totalPages = Math.ceil(countData.count / pageSize);

  for (let page = 0; page < totalPages; page++) {
    const { data } = await connectWiseApi.get<CWMember[]>(
      `/system/members?page=${page + 1}&pageSize=${pageSize}${conditionsParam}`,
    );

    for (const member of data) {
      members.set(member.identifier, member);
    }
  }

  return members;
};

/**
 * Find CW Member Identifier by Email
 *
 * Looks up a ConnectWise member whose `officeEmail` matches the provided
 * email address (case-insensitive) and returns their `identifier` string
 * (e.g. "jroberts"). Returns `null` if no match is found.
 *
 * @param email - The email address to search for
 * @param members - Optional pre-fetched member collection to search against (avoids extra API call)
 * @returns {Promise<string | null>} The CW identifier or null
 */
export const findCwIdentifierByEmail = async (
  email: string,
  members?: Collection<string, CWMember>,
): Promise<string | null> => {
  const allMembers = members ?? (await fetchAllCwMembers());
  const normalised = email.toLowerCase();

  const match = allMembers.find(
    (m) => m.officeEmail?.toLowerCase() === normalised,
  );

  return match?.identifier ?? null;
};