"use client";

import {
  BoltIcon,
  CheckCircleIcon,
  FireIcon,
  GlobeAltIcon,
  MagnifyingGlassIcon,
  MapPinIcon,
  PlusIcon,
  TrophyIcon,
  UserGroupIcon,
} from "@heroicons/react/24/outline";
import { useMemo, useState } from "react";
import {
  ClubActivityCategory,
  ClubScope,
  GermanState,
  clubCategories,
  defaultClubProfile,
  germanStates,
  todayKey,
} from "@/lib/hellth-data";
import { trpc } from "@/lib/trpc";

type ClubForm = {
  title: string;
  category: ClubActivityCategory;
  scope: ClubScope;
  date: string;
  time: string;
  durationMinutes: string;
  points: string;
  note: string;
};

type ClubProfileView = {
  userId: string;
  state: string;
  city?: string | null;
  latitude?: number | null;
  longitude?: number | null;
  privacyMode: "city" | "state";
};

const initialForm: ClubForm = {
  title: "",
  category: "walk",
  scope: "state",
  date: todayKey(),
  time: "18:00",
  durationMinutes: "60",
  points: "100",
  note: "",
};

function formatDateTime(value: string) {
  return new Date(value).toLocaleString("de-DE", {
    weekday: "short",
    day: "2-digit",
    month: "2-digit",
    hour: "2-digit",
    minute: "2-digit",
  });
}

function categoryLabel(category: string) {
  return clubCategories.find((item) => item.key === category)?.label ?? "Sonstiges";
}

function categoryStyle(category: string) {
  if (category === "walk") return "bg-emerald-50 text-emerald-700";
  if (category === "run") return "bg-orange-50 text-orange-700";
  if (category === "mobility") return "bg-blue-50 text-blue-700";
  if (category === "strength") return "bg-purple-50 text-purple-700";
  if (category === "bike") return "bg-cyan-50 text-cyan-700";
  return "bg-gray-100 text-gray-700";
}

function scopeLabel(scope: ClubScope) {
  if (scope === "local") return "Lokal";
  if (scope === "state") return "Bundesland";
  return "Deutschlandweit";
}

function distanceKm(
  profile: { latitude?: number | null; longitude?: number | null },
  activity: { latitude?: number | null; longitude?: number | null },
) {
  if (
    profile.latitude === undefined ||
    profile.latitude === null ||
    profile.longitude === undefined ||
    profile.longitude === null ||
    activity.latitude === undefined ||
    activity.latitude === null ||
    activity.longitude === undefined ||
    activity.longitude === null
  ) {
    return undefined;
  }

  const toRad = (value: number) => (value * Math.PI) / 180;
  const earthKm = 6371;
  const deltaLat = toRad(activity.latitude - profile.latitude);
  const deltaLon = toRad(activity.longitude - profile.longitude);
  const lat1 = toRad(profile.latitude);
  const lat2 = toRad(activity.latitude);
  const haversine =
    Math.sin(deltaLat / 2) ** 2 +
    Math.cos(lat1) * Math.cos(lat2) * Math.sin(deltaLon / 2) ** 2;
  return Math.round(earthKm * 2 * Math.atan2(Math.sqrt(haversine), Math.sqrt(1 - haversine)));
}

function locationLabel(profile: { state: string; city?: string | null; privacyMode: string }, scope: ClubScope) {
  if (scope === "nationwide") return "Deutschlandweit";
  if (scope === "state" || profile.privacyMode === "state") return profile.state;
  return profile.city?.trim() || profile.state;
}

export default function HellfireclubPage() {
  const utils = trpc.useUtils();
  const [query, setQuery] = useState("");
  const [category, setCategory] = useState<ClubActivityCategory | "all">("all");
  const [scope, setScope] = useState<ClubScope>("state");
  const [form, setForm] = useState<ClubForm>(initialForm);
  const [status, setStatus] = useState<string | null>(null);
  const [locationStatus, setLocationStatus] = useState<string | null>(null);

  const profileQuery = trpc.health.clubProfile.useQuery();
  const activitiesQuery = trpc.health.clubActivities.useQuery({});
  const pointDefaultsQuery = trpc.health.pointDefaults.useQuery();
  const leaderboardQuery = trpc.health.clubLeaderboard.useQuery({ days: 90 });
  const upsertProfileMutation = trpc.health.upsertClubProfile.useMutation({
    onSuccess: () => utils.health.clubProfile.invalidate(),
  });
  const createActivityMutation = trpc.health.createClubActivity.useMutation({
    onSuccess: async () => {
      await utils.health.clubActivities.invalidate();
      setForm(initialForm);
      setStatus("Aktivität erstellt. Andere User können jetzt passend zu deinem Gebiet mitmachen.");
    },
  });
  const joinActivityMutation = trpc.health.joinClubActivity.useMutation({
    onSuccess: async () => {
      await utils.health.clubActivities.invalidate();
      setStatus("Du bist dabei. Die Aktivität ist in deinem Hellfireclub vorgemerkt.");
    },
  });
  const completeActivityMutation = trpc.health.completeClubActivity.useMutation({
    onSuccess: async () => {
      await Promise.all([
        utils.health.clubActivities.invalidate(),
        utils.health.clubLeaderboard.invalidate(),
        utils.health.activityWeek.invalidate(),
        utils.health.overview.invalidate(),
      ]);
      setStatus("Punkte gutgeschrieben und als Aktivität gespeichert.");
    },
  });

  const rawProfile = profileQuery.data;
  const clubActivityDefaultPoints = pointDefaultsQuery.data?.clubActivityDefaultPoints ?? 100;
  const profile: ClubProfileView = {
    userId: rawProfile?.userId ?? "",
    state: rawProfile?.state ?? defaultClubProfile.state,
    city: rawProfile?.city ?? defaultClubProfile.city,
    latitude: rawProfile?.latitude == null ? null : Number(rawProfile.latitude),
    longitude: rawProfile?.longitude == null ? null : Number(rawProfile.longitude),
    privacyMode: (rawProfile?.privacyMode ?? defaultClubProfile.privacyMode) as "city" | "state",
  };
  const activities = activitiesQuery.data ?? [];

  function updateProfile(patch: Partial<ClubProfileView>) {
    const next = { ...profile, ...patch };
    upsertProfileMutation.mutate({
      state: next.state,
      city: next.city ?? null,
      latitude: next.latitude == null ? null : Number(next.latitude),
      longitude: next.longitude == null ? null : Number(next.longitude),
      privacyMode: next.privacyMode as "city" | "state",
    });
  }

  function requestLocation() {
    if (!navigator.geolocation) {
      setLocationStatus("Dein Browser unterstützt keine Standortfreigabe.");
      return;
    }
    setLocationStatus("Standort wird abgefragt...");
    navigator.geolocation.getCurrentPosition(
      (position) => {
        updateProfile({
          latitude: position.coords.latitude,
          longitude: position.coords.longitude,
        });
        setLocationStatus("Standort gespeichert. Sichtbar bleibt nur Stadt oder Bundesland.");
      },
      () => setLocationStatus("Standort konnte nicht gelesen werden. Bundesland-Filter funktioniert weiterhin."),
      { enableHighAccuracy: false, maximumAge: 1000 * 60 * 30, timeout: 8000 },
    );
  }

  const filteredActivities = useMemo(() => {
    const needle = query.trim().toLowerCase();
    return activities
      .filter((activity) => {
        const activityScope = (activity.scope ?? "nationwide") as ClubScope;
        if (scope === "nationwide" || activityScope === "nationwide") return true;
        if (scope === "state") return activity.state === profile.state;
        if (activity.state !== profile.state) return false;
        const distance = distanceKm(profile, activity);
        if (distance !== undefined) return distance <= 30;
        return Boolean(activity.city && profile.city && activity.city.toLowerCase() === profile.city.toLowerCase());
      })
      .filter((activity) => category === "all" || activity.category === category)
      .filter((activity) => {
        if (!needle) return true;
        return [activity.title, activity.hostName, activity.note, activity.locationLabel, activity.city, activity.state, categoryLabel(activity.category)]
          .filter(Boolean)
          .some((value) => value!.toLowerCase().includes(needle));
      })
      .sort((a, b) => {
        const distanceA = distanceKm(profile, a) ?? Number.MAX_SAFE_INTEGER;
        const distanceB = distanceKm(profile, b) ?? Number.MAX_SAFE_INTEGER;
        if (scope === "local" && distanceA !== distanceB) return distanceA - distanceB;
        return new Date(a.startsAt).getTime() - new Date(b.startsAt).getTime();
      });
  }, [activities, category, profile, query, scope]);

  const leaderboard = leaderboardQuery.data ?? [];

  function createActivity() {
    if (!form.title.trim()) return;
    createActivityMutation.mutate({
      title: form.title.trim(),
      category: form.category,
      scope: form.scope,
      state: profile.state,
      city: profile.city ?? null,
      latitude: profile.latitude == null ? null : Number(profile.latitude),
      longitude: profile.longitude == null ? null : Number(profile.longitude),
      locationLabel: locationLabel(profile, form.scope),
      startsAt: `${form.date}T${form.time}:00.000Z`,
      durationMinutes: Number(form.durationMinutes) || 30,
      points: Number(form.points) || clubActivityDefaultPoints,
      note: form.note.trim() || null,
    });
  }

  return (
    <div className="mx-auto max-w-6xl space-y-5 pb-24">
      <header className="overflow-hidden rounded-[2rem] bg-gray-950 p-6 text-white shadow-sm">
        <div className="flex flex-col gap-6 lg:flex-row lg:items-end lg:justify-between">
          <div>
            <p className="text-sm font-black uppercase text-red-300">Hellfireclub</p>
            <h1 className="mt-2 text-4xl font-black tracking-normal">Gemeinsam getrennt aktiv</h1>
            <p className="mt-3 max-w-3xl text-sm font-semibold text-white/60">
              Lokale Challenges, Bundesland-Events und deutschlandweite Aktivitäten. Jetzt persistent über API und Datenbank.
            </p>
          </div>
          <div className="grid h-28 w-28 place-items-center rounded-full bg-red-500 text-white ring-[12px] ring-red-500/20">
            <FireIcon className="h-14 w-14" />
          </div>
        </div>
      </header>

      <section className="grid gap-4 lg:grid-cols-[1fr_0.8fr]">
        <section className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
          <div className="flex flex-col gap-3 md:flex-row">
            <div className="flex min-w-0 flex-1 items-center gap-3 rounded-full bg-gray-100 px-4 py-3">
              <MagnifyingGlassIcon className="h-5 w-5 text-gray-400" />
              <input
                value={query}
                onChange={(event) => setQuery(event.target.value)}
                placeholder="Aktivität, Ort oder Kategorie suchen"
                className="min-w-0 flex-1 bg-transparent text-sm font-semibold outline-none"
              />
            </div>
            <select
              value={category}
              onChange={(event) => setCategory(event.target.value as ClubActivityCategory | "all")}
              className="rounded-full border border-gray-200 bg-white px-4 py-3 text-sm font-black text-gray-950"
            >
              <option value="all">Alle Kategorien</option>
              {clubCategories.map((item) => <option key={item.key} value={item.key}>{item.label}</option>)}
            </select>
          </div>

          <div className="mt-4 grid grid-cols-3 gap-2 rounded-full bg-gray-100 p-1">
            {(["local", "state", "nationwide"] as ClubScope[]).map((item) => (
              <button
                key={item}
                type="button"
                onClick={() => setScope(item)}
                className={`rounded-full px-3 py-2 text-xs font-black transition ${scope === item ? "bg-gray-950 text-white" : "text-gray-500"}`}
              >
                {scopeLabel(item)}
              </button>
            ))}
          </div>

          <div className="mt-5 space-y-3">
            {filteredActivities.map((activity) => {
              const participant = activity.participants.find((item) => item.userId === profile.userId);
              const completed = Boolean(participant?.completedAt);
              const distance = distanceKm(profile, activity);
              return (
                <article key={activity.id} className="rounded-[2rem] bg-gray-50 p-5">
                  <div className="flex flex-col gap-4 sm:flex-row sm:items-start sm:justify-between">
                    <div>
                      <div className="flex flex-wrap items-center gap-2">
                        <span className={`rounded-full px-3 py-1 text-xs font-black ${categoryStyle(activity.category)}`}>
                          {categoryLabel(activity.category)}
                        </span>
                        <span className="rounded-full bg-white px-3 py-1 text-xs font-black text-gray-400">
                          {activity.points} Punkte
                        </span>
                        <span className="inline-flex items-center gap-1 rounded-full bg-white px-3 py-1 text-xs font-black text-gray-500">
                          {activity.scope === "nationwide" ? <GlobeAltIcon className="h-4 w-4" /> : <MapPinIcon className="h-4 w-4" />}
                          {activity.locationLabel ?? scopeLabel((activity.scope ?? "nationwide") as ClubScope)}
                          {distance !== undefined ? ` · ${distance} km` : ""}
                        </span>
                      </div>
                      <h2 className="mt-3 text-2xl font-black text-gray-950">{activity.title}</h2>
                      <p className="mt-1 text-sm font-bold text-gray-400">
                        {activity.hostName} möchte am {formatDateTime(activity.startsAt)} für {activity.durationMinutes} Minuten los.
                      </p>
                      {activity.note ? <p className="mt-3 text-sm font-semibold text-gray-500">{activity.note}</p> : null}
                    </div>
                    <div className="flex min-w-44 flex-col gap-2">
                      <button
                        type="button"
                        disabled={Boolean(participant)}
                        onClick={() => joinActivityMutation.mutate({ id: activity.id })}
                        className="rounded-full bg-gray-950 px-4 py-3 text-sm font-black text-white disabled:bg-gray-200 disabled:text-gray-500"
                      >
                        {participant ? "Du bist dabei" : "Mitgehen"}
                      </button>
                      <button
                        type="button"
                        disabled={completed}
                        onClick={() => completeActivityMutation.mutate({ id: activity.id })}
                        className="rounded-full bg-emerald-600 px-4 py-3 text-sm font-black text-white disabled:bg-emerald-100 disabled:text-emerald-700"
                      >
                        {completed ? "Abgeschlossen" : "Abschließen"}
                      </button>
                    </div>
                  </div>

                  <div className="mt-4 flex flex-wrap items-center gap-2 text-sm font-bold text-gray-400">
                    <UserGroupIcon className="h-5 w-5" />
                    {activity.participants.length || 0} dabei
                    {activity.participants.length > 0 ? <span className="text-gray-300">{activity.participants.map((item) => item.displayName).join(", ")}</span> : null}
                  </div>
                </article>
              );
            })}
            {!filteredActivities.length ? <p className="rounded-3xl bg-gray-50 p-5 text-sm font-bold text-gray-400">Für diesen Filter gibt es noch keine Aktivitäten.</p> : null}
          </div>
        </section>

        <aside className="space-y-4">
          <section className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
            <div className="flex items-center gap-3">
              <MapPinIcon className="h-7 w-7 text-red-500" />
              <h2 className="text-xl font-black text-gray-950">Club-Profil</h2>
            </div>
            <div className="mt-4 grid gap-3">
              <input
                value={profile.city ?? ""}
                onChange={(event) => updateProfile({ city: event.target.value })}
                placeholder="Stadt, z. B. Augsburg"
                className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold"
              />
              <select
                value={profile.state}
                onChange={(event) => updateProfile({ state: event.target.value as GermanState })}
                className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold"
              >
                {germanStates.map((state) => <option key={state} value={state}>{state}</option>)}
              </select>
              <div className="grid grid-cols-2 gap-2 rounded-2xl bg-gray-100 p-1">
                {(["city", "state"] as const).map((mode) => (
                  <button
                    key={mode}
                    type="button"
                    onClick={() => updateProfile({ privacyMode: mode })}
                    className={`rounded-xl px-3 py-2 text-xs font-black ${profile.privacyMode === mode ? "bg-white text-gray-950 shadow-sm" : "text-gray-500"}`}
                  >
                    {mode === "city" ? "Stadt zeigen" : "Bundesland"}
                  </button>
                ))}
              </div>
              <button type="button" onClick={requestLocation} className="inline-flex items-center justify-center gap-2 rounded-full bg-gray-950 px-4 py-3 text-sm font-black text-white">
                <MapPinIcon className="h-5 w-5" />
                Standort verwenden
              </button>
              {locationStatus ? <p className="text-xs font-bold text-gray-500">{locationStatus}</p> : null}
            </div>
          </section>

          <section className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
            <h2 className="text-xl font-black text-gray-950">Aktivität erstellen</h2>
            <div className="mt-4 grid gap-3">
              <input value={form.title} onChange={(event) => setForm((current) => ({ ...current, title: event.target.value }))} placeholder="z. B. Eine Stunde spazieren gehen" className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
              <select value={form.category} onChange={(event) => setForm((current) => ({ ...current, category: event.target.value as ClubActivityCategory }))} className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold">
                {clubCategories.map((item) => <option key={item.key} value={item.key}>{item.label}</option>)}
              </select>
              <select value={form.scope} onChange={(event) => setForm((current) => ({ ...current, scope: event.target.value as ClubScope }))} className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold">
                <option value="local">Lokal in deiner Nähe</option>
                <option value="state">Im Bundesland</option>
                <option value="nationwide">Deutschlandweit</option>
              </select>
              <div className="grid grid-cols-2 gap-2">
                <input type="date" value={form.date} onChange={(event) => setForm((current) => ({ ...current, date: event.target.value }))} className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
                <input type="time" value={form.time} onChange={(event) => setForm((current) => ({ ...current, time: event.target.value }))} className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
                <input value={form.durationMinutes} onChange={(event) => setForm((current) => ({ ...current, durationMinutes: event.target.value }))} placeholder="Minuten" className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
                <input value={form.points} onChange={(event) => setForm((current) => ({ ...current, points: event.target.value }))} placeholder="Punkte" className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
              </div>
              <textarea value={form.note} onChange={(event) => setForm((current) => ({ ...current, note: event.target.value }))} placeholder="Notiz, Treffpunkt oder Motivation" className="min-h-24 rounded-3xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
              <button type="button" onClick={createActivity} className="inline-flex items-center justify-center gap-2 rounded-full bg-gray-950 px-4 py-4 text-sm font-black text-white">
                <PlusIcon className="h-5 w-5" />
                Einladen
              </button>
            </div>
          </section>

          <section className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
            <div className="flex items-center gap-3">
              <TrophyIcon className="h-8 w-8 text-amber-500" />
              <h2 className="text-xl font-black text-gray-950">Highscore</h2>
            </div>
            <div className="mt-4 space-y-2">
              {leaderboard.length ? leaderboard.map((entry, index) => (
                <div key={entry.userKey} className="flex items-center gap-3 rounded-2xl bg-gray-50 p-3">
                  <div className="grid h-9 w-9 place-items-center rounded-full bg-gray-950 text-sm font-black text-white">{index + 1}</div>
                  <div className="min-w-0 flex-1">
                    <p className="truncate text-sm font-black text-gray-950">{entry.name}</p>
                    <p className="text-xs font-bold text-gray-400">{entry.completed} Punkte-Einträge</p>
                  </div>
                  <div className="text-right">
                    <p className="text-lg font-black text-gray-950">{entry.points}</p>
                    <p className="text-xs font-bold text-gray-400">Punkte</p>
                  </div>
                </div>
              )) : (
                <p className="rounded-2xl bg-gray-50 p-4 text-sm font-bold text-gray-400">Noch keine Punkte gesammelt.</p>
              )}
            </div>
          </section>

          {status ? (
            <div className="flex gap-2 rounded-3xl bg-emerald-50 p-4 text-sm font-bold text-emerald-800">
              <CheckCircleIcon className="h-5 w-5 shrink-0" />
              {status}
            </div>
          ) : null}
        </aside>
      </section>

      <section className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
        <div className="flex items-start gap-3">
          <BoltIcon className="h-7 w-7 text-red-500" />
          <div>
            <h2 className="text-lg font-black text-gray-950">Persistenter Club</h2>
            <p className="mt-1 text-sm font-semibold text-gray-400">
              Aktivitäten, Teilnahmen, Abschlüsse und Punkte werden jetzt in der Datenbank gespeichert.
            </p>
          </div>
        </div>
      </section>
    </div>
  );
}