import { useEffect, useState } from "react";
import axios from "axios";
import { Card, CardHeader, CardBody, Divider } from "@heroui/react";
import { useLanguageStore } from "@/stores/languageStore";
import { useContestStore, type ContestSummary, type RoundSummary } from "@/stores/contestStore";
import { useTranslation } from "react-i18next";

type RoundDetailProps = {
  roundId: number;
};

type RoundDetailData = RoundSummary & {
  contest_id: number;
  contest?: ContestSummary | null;
  description?: string | Record<string, string> | null;
  logs_deadline?: string | null;
  start_time: string | null;
  end_time: string | null;
  rule_set_id?: number | null;
  rule_set?: { id: number; name: string } | null;
  preliminary_evaluation_run_id?: number | null;
  official_evaluation_run_id?: number | null;
  test_evaluation_run_id?: number | null;
};

function parseRoundDate(value: string | null): Date | null {
  if (!value) return null;
  const direct = new Date(value);
  if (!Number.isNaN(direct.getTime())) return direct;
  const normalized = value.includes("T") ? value : value.replace(" ", "T");
  const fallback = new Date(normalized);
  if (!Number.isNaN(fallback.getTime())) return fallback;
  return null;
}

function formatDateTime(value: string | null, locale: string): string {
  if (!value) return "—";
  const date = parseRoundDate(value);
  if (!date) return value;
  return date.toLocaleString(locale);
}

function isPastDeadline(value: string | null): boolean {
  const date = parseRoundDate(value);
  if (!date) return false;
  return (new Date() > date);
}

const resolveTranslation = (field: any, locale: string): string => {
  if (!field) return "";
  if (typeof field === "string") return field;
  if (typeof field === "object") {
    if (field[locale]) return field[locale];
    if (field["en"]) return field["en"];
    const first = Object.values(field)[0];
    return typeof first === "string" ? first : "";
  }
  return String(field);
};

export default function RoundDetail({ roundId }: RoundDetailProps) {
  const { t } = useTranslation("common");
  const locale = useLanguageStore((s) => s.locale);
  const setSelectedContest = useContestStore((s) => s.setSelectedContest);
  const setSelectedRound = useContestStore((s) => s.setSelectedRound);

  const [detail, setDetail] = useState<RoundDetailData | null>(null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    if (!roundId) return;

    let active = true;
    (async () => {
      try {
        setLoading(true);
        setError(null);
        const res = await axios.get<RoundDetailData>(`/api/rounds/${roundId}`, {
          headers: { Accept: "application/json" },
          params: { lang: locale },
          withCredentials: true,
        });

        if (!active) return;
        setDetail(res.data);

        // set store for breadcrumbs/overview
        if (res.data.contest) {
          setSelectedContest({
            id: res.data.contest.id,
            name: resolveTranslation((res.data as any).contest.name, locale),
            description: resolveTranslation((res.data as any).contest.description ?? null, locale),
            is_active: res.data.contest.is_active,
            is_mcr: res.data.contest.is_mcr,
            is_sixhr: res.data.contest.is_sixhr,
            start_time: res.data.contest.start_time ?? null,
            duration: res.data.contest.duration ?? 0,
          });
        }
        setSelectedRound({
          id: res.data.id,
          contest_id: res.data.contest_id,
          name: resolveTranslation(res.data.name, locale),
          description: resolveTranslation(res.data.description ?? null, locale),
          is_active: res.data.is_active,
          is_test: res.data.is_test,
          is_sixhr: res.data.is_sixhr,
          start_time: res.data.start_time,
          end_time: res.data.end_time,
          logs_deadline: res.data.logs_deadline ?? null,
          preliminary_evaluation_run_id: res.data.preliminary_evaluation_run_id ?? null,
          official_evaluation_run_id: res.data.official_evaluation_run_id ?? null,
          test_evaluation_run_id: res.data.test_evaluation_run_id ?? null,
        });
      } catch {
        if (!active) return;
        setError("Nepodařilo se načíst detail kola.");
      } finally {
        if (active) setLoading(false);
      }
    })();

    return () => {
      active = false;
    };
  }, [roundId, locale, setSelectedContest, setSelectedRound]);

  return (
    <Card>
      <CardHeader>
        <div className="flex flex-col">
          <span className="text-lg font-semibold">
            {detail ? resolveTranslation(detail.name, locale) : t("round_name") ?? "Kolo"}
          </span>
          {detail?.description && (
            <span className="text-sm text-foreground-500">
              {resolveTranslation(detail.description, locale)}
            </span>
          )}
        </div>
      </CardHeader>
      <Divider />
      <CardBody>
        {error && <p className="text-sm text-red-600">{error}</p>}
        {loading && <p className="text-sm text-foreground-500">Načítám detail…</p>}
        {detail && !loading && (
          <div className="grid gap-2 text-sm">
            <div className="flex gap-2">
              <span className="font-semibold">{t("round_schedule") ?? "Termín"}:</span>
              <span>{formatDateTime(detail.start_time, locale)} — {formatDateTime(detail.end_time, locale)}</span>
            </div>
            {detail.logs_deadline && (
              <div className="flex gap-2">
                <span className="font-semibold">{t("round_logs_deadline") ?? "Logy do"}:</span>
                <span>{formatDateTime(detail.logs_deadline, locale)}</span>
                {detail.logs_deadline && isPastDeadline(detail.logs_deadline) && (
                    <span>
                    {t("round_logs_deadline_passed") ??
                    "Termín pro nahrání logů již vypršel."}
                    </span>
                )}
              </div>
            )}
            <div className="flex gap-2">
              <span className="font-semibold">{t("round_active") ?? "Aktivní"}:</span>
              <span>{detail.is_active ? (t("yes") ?? "Ano") : (t("no") ?? "Ne")}</span>
            </div>
            {detail.is_test && (
              <div className="flex gap-2">
                <span className="font-semibold">{t("round_test") ?? "Test"}:</span>
                <span>{t("yes") ?? "Ano"}</span>
              </div>
            )}
            <div className="flex gap-2">
              <span className="font-semibold">6h:</span>
              <span>{detail.is_sixhr ? (t("yes") ?? "Ano") : (t("no") ?? "Ne")}</span>
            </div>
            {(detail.rule_set || detail.rule_set_id) && (
              <div className="flex gap-2">
                <span className="font-semibold">Ruleset:</span>
                <span>{detail.rule_set?.name ?? `#${detail.rule_set_id}`}</span>
              </div>
            )}
          </div>
        )}
      </CardBody>
    </Card>
  );
}