"use client";

import {
  BoltIcon,
  CalendarDaysIcon,
  FireIcon,
  PlusIcon,
  SparklesIcon,
  TrashIcon,
} from "@heroicons/react/24/outline";
import { useMemo, useState } from "react";
import { trpc } from "@/lib/trpc";

type TemplateCategory = "mobility" | "cardio" | "strength" | "habit" | string;
type ActivitySource = "manual" | "fitbit";

function todayKey() {
  return new Date().toISOString().slice(0, 10);
}

function startOfWeek(dateKey: string) {
  const date = new Date(`${dateKey}T12:00:00`);
  const day = date.getDay() === 0 ? 7 : date.getDay();
  date.setDate(date.getDate() - day + 1);
  return date.toISOString().slice(0, 10);
}

function pointsLabel(points: number) {
  if (points >= 500) return "Starke Woche";
  if (points >= 250) return "Guter Lauf";
  if (points >= 100) return "In Bewegung";
  return "Startklar";
}

function categoryColor(category: TemplateCategory) {
  if (category.includes("cardio")) return "bg-orange-50 text-orange-700";
  if (category.includes("strength")) return "bg-blue-50 text-blue-700";
  if (category.includes("mobility")) return "bg-emerald-50 text-emerald-700";
  if (category.includes("sport")) return "bg-amber-50 text-amber-700";
  return "bg-purple-50 text-purple-700";
}

function categoryLabel(category: TemplateCategory) {
  if (category.includes("cardio")) return "Ausdauer";
  if (category.includes("strength")) return "Kraft";
  if (category.includes("mobility")) return "Beweglichkeit";
  if (category.includes("sport")) return "Sport";
  return "Routine";
}

function sourceLabel(source: string) {
  if (source === "fitbit") return "Fitbit";
  if (source === "health_connect") return "Health Connect";
  return "manuell";
}

function estimatePoints(minutes: number, calories: number) {
  return Math.max(5, Math.round(minutes * 1.2 + calories / 6));
}

export default function AktivitätenPage() {
  const utils = trpc.useUtils();
  const [selectedDate, setSelectedDate] = useState(todayKey());
  const [templateQuery, setTemplateQuery] = useState("");
  const [templateCategory, setTemplateCategory] = useState<"all" | "fitbit" | "manual">("all");
  const [customName, setCustomName] = useState("");
  const [customMinutes, setCustomMinutes] = useState("15");
  const [customPoints, setCustomPoints] = useState("30");
  const [customCalories, setCustomCalories] = useState("60");
  const [customNote, setCustomNote] = useState("");
  const [customSource, setCustomSource] = useState<ActivitySource>("manual");

  const templatesQuery = trpc.health.listActivityTemplates.useQuery();
  const activityWeekQuery = trpc.health.activityWeek.useQuery({ date: selectedDate });
  const addLogMutation = trpc.health.addActivityLog.useMutation({
    onSuccess: async () => {
      await utils.health.activityWeek.invalidate();
      await utils.health.overview.invalidate();
    },
  });
  const saveTemplateMutation = trpc.health.saveActivityTemplate.useMutation({
    onSuccess: async () => {
      await utils.health.listActivityTemplates.invalidate();
      setCustomName("");
    },
  });
  const deleteLogMutation = trpc.health.deleteActivityLog.useMutation({
    onSuccess: async () => {
      await utils.health.activityWeek.invalidate();
      await utils.health.overview.invalidate();
    },
  });

  const logs = activityWeekQuery.data?.logs ?? [];
  const templates = templatesQuery.data ?? [];
  const filteredTemplates = useMemo(() => {
    const needle = templateQuery.trim().toLowerCase();
    return templates.filter((template) => {
      const isFitbit = template.id.startsWith("fitbit-") || template.category.startsWith("fitbit_");
      if (templateCategory === "fitbit" && !isFitbit) return false;
      if (templateCategory === "manual" && isFitbit) return false;
      if (!needle) return true;
      return [template.name, template.category].some((value) => value.toLowerCase().includes(needle));
    });
  }, [templateCategory, templateQuery, templates]);
  const todayLogs = logs.filter((log) => log.date === selectedDate);
  const dayPoints = todayLogs.reduce((sum, log) => sum + log.points, 0);
  const weekPoints = logs.reduce((sum, log) => sum + log.points, 0);
  const weekMinutes = logs.reduce((sum, log) => sum + log.minutes, 0);
  const weekCalories = logs.reduce((sum, log) => sum + (log.calories ?? 0), 0);

  const weeklyDays = useMemo(() => {
    const monday = new Date(`${startOfWeek(selectedDate)}T12:00:00`);
    return Array.from({ length: 7 }, (_, index) => {
      const date = new Date(monday);
      date.setDate(monday.getDate() + index);
      const key = date.toISOString().slice(0, 10);
      const points = logs.filter((log) => log.date === key).reduce((sum, log) => sum + log.points, 0);
      return { key, label: date.toLocaleDateString("de-DE", { weekday: "narrow" }), day: date.getDate(), points };
    });
  }, [logs, selectedDate]);

  function logTemplate(template: (typeof templates)[number]) {
    const isFitbit = template.id.startsWith("fitbit-") || template.category.startsWith("fitbit_");
    addLogMutation.mutate({
      date: selectedDate,
      name: template.name,
      templateId: template.id,
      minutes: template.defaultMinutes,
      points: template.defaultPoints,
      calories: template.defaultCalories,
      source: isFitbit ? "fitbit" : "manual",
    });
  }

  function saveCustomTemplate() {
    if (!customName.trim()) return;
    saveTemplateMutation.mutate({
      name: customName.trim(),
      defaultMinutes: Number(customMinutes) || 5,
      defaultPoints: Number(customPoints) || 10,
      defaultCalories: Number(customCalories) || 0,
      category: "habit",
      icon: "custom",
    });
  }

  function addCustomLog() {
    if (!customName.trim()) return;
    const minutes = Number(customMinutes) || 5;
    const calories = Number(customCalories) || 0;
    const points = Number(customPoints) || estimatePoints(minutes, calories);
    addLogMutation.mutate({
      date: selectedDate,
      name: customName.trim(),
      minutes,
      points,
      calories,
      source: customSource,
      note: customNote.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-5 sm:flex-row sm:items-end sm:justify-between">
          <div>
            <p className="text-sm font-black uppercase text-emerald-300">Belohnungssystem</p>
            <h1 className="mt-2 text-4xl font-black tracking-normal">Aktivitätspunkte</h1>
            <p className="mt-3 max-w-2xl text-sm font-semibold text-white/60">
              Fitbit-kompatibler Katalog, verbrannte kcal und manuelle Nacherfassung für Training ohne Uhr.
            </p>
          </div>
          <div className="grid h-28 w-28 place-items-center rounded-full bg-white text-gray-950 ring-[12px] ring-white/10">
            <div className="text-center">
              <p className="text-3xl font-black">{dayPoints}</p>
              <p className="text-xs font-black text-gray-400">heute</p>
            </div>
          </div>
        </div>
      </header>

      <section className="grid gap-4 lg:grid-cols-4">
        <div className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
          <div className="flex items-center gap-3">
            <BoltIcon className="h-8 w-8 text-emerald-500" />
            <div>
              <p className="text-3xl font-black text-gray-950">{weekPoints}</p>
              <p className="text-sm font-bold text-gray-400">Punkte diese Woche</p>
            </div>
          </div>
        </div>
        <div className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
          <div className="flex items-center gap-3">
            <CalendarDaysIcon className="h-8 w-8 text-blue-500" />
            <div>
              <p className="text-3xl font-black text-gray-950">{weekMinutes}</p>
              <p className="text-sm font-bold text-gray-400">aktive Minuten</p>
            </div>
          </div>
        </div>
        <div className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
          <div className="flex items-center gap-3">
            <FireIcon className="h-8 w-8 text-orange-500" />
            <div>
              <p className="text-3xl font-black text-gray-950">{weekCalories}</p>
              <p className="text-sm font-bold text-gray-400">kcal Sportbonus</p>
            </div>
          </div>
        </div>
        <div className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
          <div className="flex items-center gap-3">
            <SparklesIcon className="h-8 w-8 text-orange-500" />
            <div>
              <p className="text-3xl font-black text-gray-950">{pointsLabel(weekPoints)}</p>
              <p className="text-sm font-bold text-gray-400">aktueller Status</p>
            </div>
          </div>
        </div>
      </section>

      <section className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
        <div className="flex flex-col gap-4 sm:flex-row sm:items-center sm:justify-between">
          <h2 className="text-xl font-black text-gray-950">Woche</h2>
          <input
            type="date"
            value={selectedDate}
            onChange={(event) => setSelectedDate(event.target.value || todayKey())}
            className="rounded-full border border-gray-200 px-4 py-3 text-sm font-bold"
          />
        </div>
        <div className="mt-5 grid grid-cols-7 gap-2">
          {weeklyDays.map((day) => {
            const active = day.key === selectedDate;
            return (
              <button
                key={day.key}
                type="button"
                onClick={() => setSelectedDate(day.key)}
                className={`min-h-20 rounded-3xl p-2 text-center ${active ? "bg-gray-950 text-white" : "bg-gray-50 text-gray-400"}`}
              >
                <p className="text-sm font-black uppercase">{day.label}</p>
                <p className="text-xl font-black">{day.day}</p>
                <p className={`mt-1 text-xs font-black ${active ? "text-emerald-300" : "text-gray-300"}`}>{day.points} P</p>
              </button>
            );
          })}
        </div>
      </section>

      <section className="grid gap-4 xl:grid-cols-[1fr_0.8fr]">
        <div className="rounded-[2rem] bg-white p-5 shadow-sm ring-1 ring-gray-100">
          <div className="flex flex-col gap-3 sm:flex-row sm:items-center sm:justify-between">
            <h2 className="text-xl font-black text-gray-950">Fitness-Katalog</h2>
            <div className="flex gap-2">
              {(["all", "fitbit", "manual"] as const).map((key) => (
                <button
                  key={key}
                  type="button"
                  onClick={() => setTemplateCategory(key)}
                  className={`rounded-full px-4 py-2 text-xs font-black ${templateCategory === key ? "bg-gray-950 text-white" : "bg-gray-100 text-gray-500"}`}
                >
                  {key === "all" ? "Alle" : key === "fitbit" ? "Fitbit" : "Eigene"}
                </button>
              ))}
            </div>
          </div>
          <input
            value={templateQuery}
            onChange={(event) => setTemplateQuery(event.target.value)}
            placeholder="Aktivität suchen"
            className="mt-4 w-full rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold"
          />
          <div className="mt-5 grid gap-3 md:grid-cols-2">
            {filteredTemplates.map((template) => (
              <button
                key={template.id}
                type="button"
                onClick={() => logTemplate(template)}
                disabled={addLogMutation.isPending}
                className="rounded-3xl bg-gray-50 p-4 text-left hover:bg-gray-100 disabled:opacity-50"
              >
                <div className="flex items-start justify-between gap-3">
                  <div>
                    <p className="text-lg font-black text-gray-950">{template.name}</p>
                    <p className="mt-1 text-sm font-bold text-gray-400">
                      {template.defaultMinutes} Minuten · {categoryLabel(template.category)}
                    </p>
                    <p className="text-xs font-bold text-gray-300">ca. {template.defaultCalories} kcal Sportbonus</p>
                  </div>
                  <span className={`rounded-full px-3 py-1 text-sm font-black ${categoryColor(template.category)}`}>
                    {template.defaultPoints} P
                  </span>
                </div>
              </button>
            ))}
            {!filteredTemplates.length && !templatesQuery.isLoading ? (
              <p className="rounded-3xl bg-gray-50 p-4 text-sm font-bold text-gray-400">Keine passende Vorlage gefunden.</p>
            ) : null}
          </div>
        </div>

        <aside className="space-y-4">
          <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 nacherfassen</h2>
            <div className="mt-4 grid gap-3">
              <input value={customName} onChange={(event) => setCustomName(event.target.value)} placeholder="z. B. 15 Minuten Yoga" className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
              <select value={customSource} onChange={(event) => setCustomSource(event.target.value as ActivitySource)} className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold">
                <option value="manual">Manuell erfasst</option>
                <option value="fitbit">Fitbit nachgetragen</option>
              </select>
              <div className="grid grid-cols-2 gap-2">
                <input value={customMinutes} onChange={(event) => setCustomMinutes(event.target.value)} placeholder="Minuten" className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
                <input value={customPoints} onChange={(event) => setCustomPoints(event.target.value)} placeholder="Punkte" className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
                <input value={customCalories} onChange={(event) => setCustomCalories(event.target.value)} placeholder="kcal" className="rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
              </div>
              <textarea value={customNote} onChange={(event) => setCustomNote(event.target.value)} placeholder="Notiz optional" className="min-h-20 rounded-2xl border border-gray-200 px-4 py-3 text-sm font-semibold" />
              <button
                type="button"
                onClick={addCustomLog}
                disabled={addLogMutation.isPending}
                className="inline-flex items-center justify-center gap-2 rounded-full bg-emerald-600 px-4 py-4 text-sm font-black text-white disabled:opacity-50"
              >
                <PlusIcon className="h-5 w-5" />
                Für {new Date(`${selectedDate}T12:00:00`).toLocaleDateString("de-DE")} eintragen
              </button>
              <button
                type="button"
                onClick={saveCustomTemplate}
                disabled={saveTemplateMutation.isPending}
                className="inline-flex items-center justify-center gap-2 rounded-full bg-gray-950 px-4 py-4 text-sm font-black text-white disabled:opacity-50"
              >
                <PlusIcon className="h-5 w-5" />
                Zusätzlich als Vorlage speichern
              </button>
            </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">Heute eingetragen</h2>
            <div className="mt-4 space-y-2">
              {todayLogs.length ? todayLogs.map((log) => (
                <div key={log.id} className="flex items-center gap-3 rounded-2xl bg-gray-50 p-3">
                  <FireIcon className="h-6 w-6 text-orange-500" />
                  <div className="min-w-0 flex-1">
                    <p className="truncate text-sm font-black text-gray-950">{log.name}</p>
                    <p className="text-xs font-bold text-gray-400">
                      {log.minutes} min · {log.points} Punkte · {log.calories ?? 0} kcal · {sourceLabel(log.source)}
                    </p>
                  </div>
                  <button
                    type="button"
                    onClick={() => deleteLogMutation.mutate({ id: log.id })}
                    className="rounded-full p-2 text-red-500 hover:bg-red-50"
                    aria-label="Eintrag löschen"
                    title="Eintrag löschen"
                  >
                    <TrashIcon className="h-4 w-4" />
                  </button>
                </div>
              )) : (
                <p className="rounded-2xl bg-gray-50 p-4 text-sm font-bold text-gray-400">Noch keine Aktivität für diesen Tag.</p>
              )}
            </div>
          </section>
        </aside>
      </section>
    </div>
  );
}