'use client';

import React, { useState, useEffect, useCallback, useRef } from 'react';
import { motion, AnimatePresence } from 'framer-motion';
import { Heart, Clock, Loader2 } from 'lucide-react';
import { stickerApi, type StickerRecord } from '../services/chatApiService';
import { getStickerFromCache, setStickerInCache } from '../hooks/useStickerCache';

const API = process.env.NEXT_PUBLIC_API_URL ?? 'http://localhost:3003';
const LIST_VERSION_KEY = 'nw:sticker-list-version';

interface StickerPanelProps {
  instanceId: string;
  jid: string;
  onSend: (blob: Blob) => void;
}

// Converte URL Wasabi → URL do proxy do backend
function stickerSrcUrl(wasabiPath: string): string {
  const clean = wasabiPath.startsWith('/') ? wasabiPath.slice(1) : wasabiPath;
  return `${API}/api/storage/view/${clean}`;
}

// Carrega sticker: tenta IndexedDB, depois proxy, depois persiste no cache
function useStickerBlob(sticker: StickerRecord) {
  const [dataUrl, setDataUrl] = useState<string | null>(null);

  useEffect(() => {
    let cancelled = false;
    getStickerFromCache(sticker.sha256).then((cached) => {
      if (cancelled) return;
      if (cached) { setDataUrl(cached); return; }

      // Carrega do proxy e converte para dataURL via canvas
      const img = new Image();
      img.crossOrigin = 'anonymous';
      img.onload = () => {
        if (cancelled) return;
        try {
          const canvas = document.createElement('canvas');
          canvas.width  = img.naturalWidth  || 96;
          canvas.height = img.naturalHeight || 96;
          const ctx = canvas.getContext('2d');
          if (!ctx) { setDataUrl(img.src); return; }
          ctx.drawImage(img, 0, 0);
          const url = canvas.toDataURL('image/webp', 0.9);
          setDataUrl(url);
          setStickerInCache(sticker.sha256, url);
        } catch {
          setDataUrl(img.src);
        }
      };
      img.onerror = () => { if (!cancelled) setDataUrl(null); };
      img.src = stickerSrcUrl(sticker.wasabiPath);
    });
    return () => { cancelled = true; };
  }, [sticker.sha256, sticker.wasabiPath]);

  return dataUrl;
}

// Item individual de sticker
function StickerItem({
  sticker,
  onSend,
  onToggleFavorite,
}: {
  sticker: StickerRecord;
  onSend: (s: StickerRecord) => void;
  onToggleFavorite: (s: StickerRecord) => void;
}) {
  const dataUrl = useStickerBlob(sticker);
  const [hovering, setHovering] = useState(false);

  return (
    <div
      className="relative group cursor-pointer"
      onMouseEnter={() => setHovering(true)}
      onMouseLeave={() => setHovering(false)}
      onClick={() => dataUrl && onSend(sticker)}
    >
      <div className="w-16 h-16 flex items-center justify-center rounded-xl hover:bg-black/5 transition-all active:scale-90 p-1">
        {dataUrl ? (
          <img
            src={dataUrl}
            alt=""
            className="w-full h-full object-contain"
            loading="lazy"
          />
        ) : (
          <div className="w-10 h-10 bg-gray-100 rounded-lg animate-pulse" />
        )}
      </div>

      {/* Botão de favoritar — aparece no hover */}
      {hovering && (
        <button
          className={`absolute top-0.5 right-0.5 p-0.5 rounded-full transition-all z-10 ${
            sticker.isFavorite
              ? 'text-red-400 bg-white/90'
              : 'text-gray-300 bg-white/80 hover:text-red-400'
          }`}
          onClick={(e) => { e.stopPropagation(); onToggleFavorite(sticker); }}
          title={sticker.isFavorite ? 'Remover dos favoritos' : 'Favoritar'}
        >
          <Heart className="w-3 h-3" fill={sticker.isFavorite ? 'currentColor' : 'none'} />
        </button>
      )}
    </div>
  );
}

export default function StickerPanel({ instanceId, jid, onSend }: StickerPanelProps) {
  const [tab, setTab] = useState<'recent' | 'favorites'>('recent');
  const [stickers, setStickers] = useState<StickerRecord[]>([]);
  const [loading, setLoading] = useState(true);
  const fetchedRef = useRef(false);

  const load = useCallback(async (force = false) => {
    setLoading(true);
    try {
      const { listVersion, stickers: list } = await stickerApi.list();

      if (!force) {
        const cached = localStorage.getItem(LIST_VERSION_KEY);
        if (cached === listVersion) {
          // versão igual — sem novidades, mas ainda mostra o que temos
        }
        localStorage.setItem(LIST_VERSION_KEY, listVersion);
      }
      setStickers(list);
    } catch {
      // silencioso — sem stickers ainda
    } finally {
      setLoading(false);
    }
  }, []);

  useEffect(() => {
    if (fetchedRef.current) return;
    fetchedRef.current = true;
    load();
  }, [load]);

  const handleSend = useCallback(async (sticker: StickerRecord) => {
    const dataUrl = await getStickerFromCache(sticker.sha256);
    if (!dataUrl) return;

    // Converte dataURL → Blob → envia
    const res = await fetch(dataUrl);
    const blob = await res.blob();
    onSend(blob);
  }, [onSend]);

  const handleToggleFavorite = useCallback(async (sticker: StickerRecord) => {
    const result = await stickerApi.toggleFavorite(sticker.id);
    setStickers((prev) =>
      prev.map((s) => s.id === sticker.id ? { ...s, isFavorite: result.isFavorite } : s)
    );
  }, []);

  const displayed =
    tab === 'favorites'
      ? stickers.filter((s) => s.isFavorite)
      : stickers; // recent = all sorted by lastSeenAt (backend already sorts)

  return (
    <div className="w-72 bg-white rounded-2xl shadow-2xl border border-gray-100 overflow-hidden">
      {/* Tabs */}
      <div className="flex border-b border-gray-100">
        <button
          onClick={() => setTab('recent')}
          className={`flex-1 flex items-center justify-center gap-1.5 py-2.5 text-xs font-medium transition-colors ${
            tab === 'recent' ? 'text-[#00a884] border-b-2 border-[#00a884]' : 'text-[#54656f] hover:bg-gray-50'
          }`}
        >
          <Clock className="w-3.5 h-3.5" />
          Recentes
        </button>
        <button
          onClick={() => setTab('favorites')}
          className={`flex-1 flex items-center justify-center gap-1.5 py-2.5 text-xs font-medium transition-colors ${
            tab === 'favorites' ? 'text-[#00a884] border-b-2 border-[#00a884]' : 'text-[#54656f] hover:bg-gray-50'
          }`}
        >
          <Heart className="w-3.5 h-3.5" />
          Favoritos
        </button>
      </div>

      {/* Content */}
      <div className="h-[220px] overflow-y-auto p-2">
        {loading ? (
          <div className="flex items-center justify-center h-full text-gray-300">
            <Loader2 className="w-6 h-6 animate-spin" />
          </div>
        ) : displayed.length === 0 ? (
          <div className="flex flex-col items-center justify-center h-full gap-2 text-gray-300">
            {tab === 'favorites' ? (
              <>
                <Heart className="w-8 h-8" />
                <span className="text-xs">Nenhum favorito ainda</span>
              </>
            ) : (
              <>
                <span className="text-3xl">🙂</span>
                <span className="text-xs text-center">
                  As figurinhas que você receber<br />aparecem aqui automaticamente
                </span>
              </>
            )}
          </div>
        ) : (
          <div className="grid grid-cols-4 gap-0.5">
            {displayed.map((s) => (
              <StickerItem
                key={s.id}
                sticker={s}
                onSend={handleSend}
                onToggleFavorite={handleToggleFavorite}
              />
            ))}
          </div>
        )}
      </div>
    </div>
  );
}