"use client";

import { useEffect, useState } from "react";
import { Trophy } from "lucide-react";
import { cn } from "@/lib/utils";
import type { PresenceParticipant } from "@/hooks/useRealtimePresence";

interface ApiUser {
  id: number;
  username?: string | null;
  displayName?: string | null;
  payloadDisplayName?: string | null;
}

interface ApiProfile {
  id: number;
  profileTitle?: string | null;
  user?: ApiUser | number | null;
  progression?: {
    minigames?: {
      flappyBird?: {
        gamesPlayed?: number | null;
        totalPasses?: number | null;
        bestScore?: number | null;
        xpEarned?: number | null;
      } | null;
    } | null;
  } | null;
}

interface LeaderboardRow {
  id: number;
  userId: number | null;
  name: string;
  gamesPlayed: number;
  totalPasses: number;
  bestScore: number;
  xpEarned: number;
  isCurrentUser: boolean;
  isOutsideTopTen?: boolean;
}

interface FlappyLeaderboardProps {
  refreshKey?: number;
  currentUserId?: number | string;
  activePilots?: PresenceParticipant[];
}

function rankClass(index: number) {
  if (index === 0) return "font-bold text-amber-400";
  if (index === 1) return "font-semibold text-slate-300";
  if (index === 2) return "font-semibold text-amber-700";
  return "text-muted-foreground";
}

export function FlappyLeaderboard({ refreshKey = 0, currentUserId, activePilots = [] }: FlappyLeaderboardProps) {
  const [rows, setRows] = useState<LeaderboardRow[] | null>(null);
  const [failed, setFailed] = useState(false);

  useEffect(() => {
    let cancelled = false;
    setFailed(false);

    const params = new URLSearchParams({
      sort: "-progression.minigames.flappyBird.bestScore",
      // Fetch enough profiles to keep the current pilot visible even when
      // they have not completed a scored run yet.
      limit: "100",
      depth: "1",
    });

    fetch(`/api/profiles?${params.toString()}`)
      .then((res) => {
        if (!res.ok) throw new Error("leaderboard fetch failed");
        return res.json() as Promise<{ docs?: ApiProfile[] }>;
      })
      .then((data) => {
        if (cancelled) return;
        const mapped: LeaderboardRow[] = (data.docs ?? []).map((doc) => {
            const flappy = doc.progression?.minigames?.flappyBird ?? {};
            const user = typeof doc.user === "object" && doc.user !== null ? doc.user : null;
            const name =
              user?.displayName || doc.profileTitle || user?.username || `Pilot #${doc.id}`;
            return {
              id: doc.id,
              userId: user?.id ?? null,
              name,
              gamesPlayed: flappy.gamesPlayed ?? 0,
              totalPasses: flappy.totalPasses ?? 0,
              bestScore: flappy.bestScore ?? 0,
              xpEarned: flappy.xpEarned ?? 0,
              isCurrentUser: user ? String(user.id) === String(currentUserId) : false,
            };
          });
        const scored = mapped.filter((row) => row.bestScore > 0);
        const visible = scored.slice(0, 10);
        const current = mapped.find((row) => row.isCurrentUser);
        if (current && !visible.some((row) => row.id === current.id)) {
          visible.push({ ...current, isOutsideTopTen: true });
        }
        setRows(visible);
      })
      .catch(() => {
        if (!cancelled) setFailed(true);
      });

    return () => {
      cancelled = true;
    };
  }, [refreshKey, currentUserId]);

  return (
    <div className="w-full max-w-[420px] rounded-xl border border-border bg-card">
      <div className="flex items-center gap-2 border-b border-border px-4 py-3">
        <Trophy className="size-4 text-amber-400" />
        <h2 className="text-sm font-semibold">Flight Simulator Leaderboard</h2>
        <span className="ml-auto text-xs text-muted-foreground">Top 10 · best run (bird-free)</span>
      </div>
      <div className="border-b border-border px-4 py-2 text-xs text-muted-foreground" aria-live="polite">
        <span className="font-medium text-emerald-400">{activePilots.length}</span>{" "}
        {activePilots.length === 1 ? "pilot is" : "pilots are"} flying now
        {activePilots.length > 0 && (
          <span className="ml-1 text-foreground">({activePilots.map((pilot) => pilot.name).join(", ")})</span>
        )}
      </div>

      {failed ? (
        <p className="px-4 py-4 text-sm text-muted-foreground">Could not load the leaderboard.</p>
      ) : rows === null ? (
        <div className="space-y-2 px-4 py-4">
          <div className="h-4 w-full animate-pulse rounded bg-border" />
          <div className="h-4 w-3/4 animate-pulse rounded bg-border" />
          <div className="h-4 w-1/2 animate-pulse rounded bg-border" />
        </div>
      ) : rows.length === 0 ? (
        <p className="px-4 py-4 text-sm text-muted-foreground">
          No pilots on the board yet. Be the first to pass a pipe!
        </p>
      ) : (
        <table className="w-full text-sm">
          <thead>
            <tr className="text-left text-xs uppercase tracking-wider text-muted-foreground">
              <th className="px-4 py-2 font-medium">#</th>
              <th className="px-2 py-2 font-medium">Pilot</th>
              <th className="px-2 py-2 text-right font-medium">Games</th>
              <th className="px-2 py-2 text-right font-medium">Passes</th>
              <th className="px-2 py-2 text-right font-medium">Best</th>
              <th className="px-4 py-2 text-right font-medium">XP</th>
            </tr>
          </thead>
          <tbody className="divide-y divide-border">
            {rows.map((row, i) => (
              <tr
                key={row.id}
                className={cn(
                  row.isCurrentUser && "bg-accent/40",
                  row.isOutsideTopTen && "text-muted-foreground opacity-70",
                )}
                title={row.isOutsideTopTen ? "Pilot status: not currently ranked in the top 10" : undefined}
              >
                <td className="px-4 py-2">
                  <span className={rankClass(i)}>{row.isOutsideTopTen ? "-" : i + 1}</span>
                </td>
                <td className="px-2 py-2 font-medium">
                  <span className="flex items-center gap-2">
                    <span className="max-w-[180px] truncate">{row.name}</span>
                    {row.isCurrentUser && (
                      <span className="shrink-0 text-xs text-muted-foreground">(you)</span>
                    )}
                    {row.isOutsideTopTen && (
                      <span className="shrink-0 text-[10px] font-normal uppercase tracking-wide text-muted-foreground">
                        unranked
                      </span>
                    )}
                    {row.userId !== null && activePilots.some((pilot) => pilot.id === row.userId) && (
                      <span className="size-2 rounded-full bg-emerald-400" title="Playing now" aria-label="Playing now" />
                    )}
                  </span>
                </td>
                <td className="px-2 py-2 text-right tabular-nums text-muted-foreground">
                  {row.gamesPlayed}
                </td>
                <td className="px-2 py-2 text-right tabular-nums text-muted-foreground">
                  {row.totalPasses}
                </td>
                <td className="px-2 py-2 text-right font-semibold tabular-nums">{row.bestScore}</td>
                <td className="px-4 py-2 text-right tabular-nums text-muted-foreground">
                  {row.xpEarned}
                </td>
              </tr>
            ))}
          </tbody>
        </table>
      )}
    </div>
  );
}