import { getAuth } from "@clerk/react-router/server";
import {
  findLeagueById,
  findTeamsBySeasonId,
  findCommissionersByLeagueId,
  isUserLeagueMember,
  isCommissioner,
  findUserByClerkId,
  findDraftSlotsBySeasonId,
} from "~/models";
import { findCurrentSeasonWithSports } from "~/models/season";
import { getSeasonStandings } from "~/models/standings";
import { getNextScoringEvent } from "~/models/scoring-event";
import type { Route } from "./+types/$leagueId";

export async function loader(args: Route.LoaderArgs) {
  const { userId } = await getAuth(args);
  const { params } = args;
  const { leagueId } = params;

  // Fetch league
  const league = await findLeagueById(leagueId);

  if (!league) {
    throw new Response("League not found", { status: 404 });
  }

  // Fetch current season with sports
  const seasonWithSports = await findCurrentSeasonWithSports(leagueId);
  const season = seasonWithSports || null;

  // Fetch commissioners
  const commissioners = await findCommissionersByLeagueId(leagueId);

  // Check if current user is a commissioner
  const isUserCommissioner = userId
    ? await isCommissioner(leagueId, userId)
    : false;

  // Check if user is a member (has a team in current season)
  const isUserMember = userId
    ? await isUserLeagueMember(leagueId, userId)
    : false;

  // Check access: user must be a commissioner, a member, or an admin
  // If not logged in or not authorized, throw 403
  if (!userId) {
    throw new Response("You must be logged in to view this league", {
      status: 401,
    });
  }

  if (!isUserCommissioner && !isUserMember) {
    throw new Response("You do not have access to this league", {
      status: 403,
    });
  }

  // Fetch teams for current season
  const teams = season ? await findTeamsBySeasonId(season.id) : [];

  // Fetch draft slots if season is in pre_draft or draft status
  const draftSlots =
    season && (season.status === "pre_draft" || season.status === "draft")
      ? await findDraftSlotsBySeasonId(season.id)
      : [];

  // Fetch standings for active/completed seasons
  const standings =
    season && (season.status === "active" || season.status === "completed")
      ? await getSeasonStandings(season.id)
      : [];

  // Fetch user data for team owners
  const ownerIds = teams
    .map((t) => t.ownerId)
    .filter((id): id is string => id !== null);
  const uniqueOwnerIds = [...new Set(ownerIds)];
  const owners = await Promise.all(
    uniqueOwnerIds.map(async (ownerId) => {
      const user = await findUserByClerkId(ownerId);
      return user
        ? { clerkId: ownerId, name: user.username || user.displayName }
        : null;
    })
  );
  const ownerMap = new Map(
    owners
      .filter((o): o is NonNullable<typeof o> => o !== null)
      .map((o) => [o.clerkId, o.name])
  );

  // Fetch user data for commissioners
  const commissionerIds = commissioners.map((c) => c.userId);
  const commissionerUsers = await Promise.all(
    commissionerIds.map(async (commissionerId) => {
      const user = await findUserByClerkId(commissionerId);
      return user
        ? { clerkId: commissionerId, name: user.username || user.displayName }
        : null;
    })
  );
  const commissionerMap = new Map(
    commissionerUsers
      .filter((c): c is NonNullable<typeof c> => c !== null)
      .map((c) => [c.clerkId, c.name])
  );

  // Count available teams
  const availableTeamCount = teams.filter((t) => !t.ownerId).length;

  // Count teams with owners
  const teamsWithOwners = teams.filter((t) => t.ownerId !== null).length;

  // Get sports seasons data including next upcoming event for each
  const rawSportsSeasons = seasonWithSports?.seasonSports?.map((ss) => ss.sportsSeason) || [];

  const sportsSeasons = await Promise.all(
    rawSportsSeasons.map(async (ss) => {
      const nextEvent =
        ss.status === "active" ? await getNextScoringEvent(ss.id) : null;
      return {
        id: ss.id,
        name: ss.name,
        status: ss.status as "upcoming" | "active" | "completed",
        scoringPattern: ss.scoringPattern,
        sport: ss.sport,
        nextEvent: nextEvent
          ? { name: nextEvent.name, eventDate: nextEvent.eventDate }
          : null,
      };
    })
  );
  const sportsCount = sportsSeasons.length;

  // Check if draft order is set
  const isDraftOrderSet = draftSlots.length > 0;

  // Extract origin for client use (avoids SSR/client mismatch on invite URLs)
  const origin = new URL(args.request.url).origin;

  return {
    league,
    season,
    teams,
    commissioners,
    currentUserId: userId,
    isUserCommissioner,
    ownerMap: Object.fromEntries(ownerMap),
    commissionerMap: Object.fromEntries(commissionerMap),
    availableTeamCount,
    sportsCount,
    teamsWithOwners,
    isDraftOrderSet,
    sportsSeasons,
    standings,
    origin,
  };
}