'use client';

import { useEffect, useState } from 'react';
import { useRouter } from 'next/navigation';
import AdminGuard from '@/components/admin-guard';
import {
  authApi,
  wishlistsApi,
  itemsApi,
  settingsApi,
  type Wishlist,
  type Item,
  type Settings,
} from '@/lib/api';
import Header from '@/components/header';
import Link from 'next/link';
import ItemCard from '@/components/admin/ItemCard';
import ItemForm from '@/components/admin/ItemForm';
import ImageUpload from '@/components/image-upload';
import RichTextEditor from '@/components/RichTextEditor';

export default function AdminPage() {
  return (
    <AdminGuard>
      <AdminPageContent />
    </AdminGuard>
  );
}

function AdminPageContent() {
  const router = useRouter();

  // Single wishlist state
  const [wishlist, setWishlist] = useState<Wishlist | null>(null);
  const [items, setItems] = useState<Item[]>([]);
  const [isLoading, setIsLoading] = useState(true);

  // Settings
  const [settings, setSettings] = useState<Settings>({
    siteTitle: 'Wishlist',
    homepageSubtext: '',
    claimingEnabled: true,
    showQuantity: true,
  });
  const [adminToken, setAdminToken] = useState<string | null>(null);
  const [linkCopied, setLinkCopied] = useState(false);

  // Unified config edit state
  const [isEditingWishlist, setIsEditingWishlist] = useState(false);
  const [editForm, setEditForm] = useState({
    name: '',
    slug: '',
    description: '',
    preferences: '',
    imageUrl: '',
    isPublic: true,
    siteTitle: '',
    homepageSubtext: '',
    claimingEnabled: true,
    showQuantity: true,
  });
  const [editError, setEditError] = useState('');
  const [isWishlistImageUploading, setIsWishlistImageUploading] = useState(false);

  // Item management state
  const [editingItemId, setEditingItemId] = useState<string | null>(null);
  const [showAddItemForm, setShowAddItemForm] = useState(false);
  const [newItemError, setNewItemError] = useState('');

  const logout = async () => {
    await authApi.logout();
    router.push('/');
  };

  useEffect(() => {
    fetchData();
    fetchAdminToken();
  }, []);

  const fetchAdminToken = async () => {
    try {
      const res = await fetch('/api/admin/access-link', { credentials: 'include' });
      if (res.ok) {
        const data = await res.json();
        setAdminToken(data.token);
      }
    } catch { /* ignore */ }
  };

  const copyAdminLink = async () => {
    if (!adminToken) return;
    const url = `${window.location.origin}/?adm=${adminToken}`;
    await navigator.clipboard.writeText(url);
    setLinkCopied(true);
    setTimeout(() => setLinkCopied(false), 2000);
  };

  const fetchData = async () => {
    try {
      const [lists, settingsData] = await Promise.all([
        wishlistsApi.getAll(),
        settingsApi.getSettings(),
      ]);
      setSettings(settingsData);
      if (lists.length > 0) {
        const w = lists[0];
        setWishlist(w);
        const itemsData = await itemsApi.getAll(w.id);
        setItems(itemsData.sort((a, b) => a.sortOrder - b.sortOrder));
      }
    } catch (error) {
      console.error('Failed to fetch data:', error);
    } finally {
      setIsLoading(false);
    }
  };

  const refreshItems = async () => {
    if (!wishlist) return;
    const itemsData = await itemsApi.getAll(wishlist.id);
    setItems(itemsData.sort((a, b) => a.sortOrder - b.sortOrder));
  };

  // Wishlist edit handlers
  const startEditingWishlist = () => {
    if (!wishlist) return;
    setEditForm({
      name: wishlist.name,
      slug: wishlist.slug,
      description: wishlist.description || '',
      preferences: wishlist.preferences || '',
      imageUrl: wishlist.imageUrl || '',
      isPublic: wishlist.isPublic,
      siteTitle: settings.siteTitle,
      homepageSubtext: settings.homepageSubtext,
      claimingEnabled: settings.claimingEnabled,
      showQuantity: settings.showQuantity,
    });
    setEditError('');
    setIsEditingWishlist(true);
  };

  const handleUpdateWishlist = async (e: React.FormEvent) => {
    e.preventDefault();
    if (!wishlist) return;
    setEditError('');
    try {
      const { siteTitle, homepageSubtext, claimingEnabled, showQuantity, ...wishlistFields } = editForm;
      const [updated] = await Promise.all([
        wishlistsApi.update(wishlist.id, wishlistFields),
        settingsApi.updateSettings({ siteTitle, homepageSubtext, claimingEnabled, showQuantity }),
      ]);
      setWishlist(updated);
      setSettings({ siteTitle, homepageSubtext, claimingEnabled, showQuantity });
      setIsEditingWishlist(false);
    } catch (error: any) {
      setEditError(error.message || 'Failed to update settings');
    }
  };

  // Item handlers
  const handleCreateItem = async (itemData: Partial<Item>) => {
    if (!wishlist) return;
    setNewItemError('');
    try {
      await itemsApi.create(wishlist.id, itemData);
      setShowAddItemForm(false);
      await refreshItems();
    } catch (error: any) {
      setNewItemError(error.message || 'Failed to create item');
      throw error;
    }
  };

  const handleUpdateItem = async (itemData: Partial<Item>) => {
    if (!editingItemId) return;
    try {
      await itemsApi.update(editingItemId, itemData);
      setEditingItemId(null);
      await refreshItems();
    } catch (error: any) {
      alert(error.message || 'Failed to update item');
      throw error;
    }
  };

  const handleDeleteItem = async (itemId: string) => {
    if (!confirm('Tem certeza que deseja excluir este item?')) return;
    try {
      await itemsApi.delete(itemId);
      await refreshItems();
    } catch {
      alert('Failed to delete item');
    }
  };

  const handleMoveItemUp = async (itemId: string) => {
    const currentIndex = items.findIndex((item) => item.id === itemId);
    if (currentIndex <= 0) return;
    try {
      await itemsApi.reorder(itemId, currentIndex - 1);
      await refreshItems();
    } catch (error: any) {
      alert(error?.message || 'Failed to reorder item');
    }
  };

  const handleMoveItemDown = async (itemId: string) => {
    const currentIndex = items.findIndex((item) => item.id === itemId);
    if (currentIndex === -1 || currentIndex === items.length - 1) return;
    try {
      await itemsApi.reorder(itemId, currentIndex + 1);
      await refreshItems();
    } catch (error: any) {
      alert(error?.message || 'Failed to reorder item');
    }
  };


  const editingItem = items.find((item) => item.id === editingItemId);

  return (
    <div className="min-h-screen bg-gray-50 dark:bg-gray-900">
      <Header
        title="Dashboard"
        subtitle={wishlist ? `${items.length} itens` : undefined}
        actions={
          <>
            <Link
              href="/admin/claims"
              className="inline-flex items-center px-6 py-3 border-2 border-indigo-600 dark:border-indigo-500 text-base font-semibold rounded-lg text-indigo-600 dark:text-indigo-400 bg-white dark:bg-gray-800 hover:bg-indigo-50 dark:hover:bg-gray-700 transition-all"
            >
              Reservas
            </Link>
            <Link
              href="/admin/guests"
              className="inline-flex items-center px-6 py-3 border-2 border-indigo-600 dark:border-indigo-500 text-base font-semibold rounded-lg text-indigo-600 dark:text-indigo-400 bg-white dark:bg-gray-800 hover:bg-indigo-50 dark:hover:bg-gray-700 transition-all"
            >
              Convidados
            </Link>
            <button
              onClick={logout}
              className="inline-flex items-center px-6 py-3 border-2 border-red-600 dark:border-red-500 text-base font-semibold rounded-lg text-red-600 dark:text-red-400 bg-white dark:bg-gray-800 hover:bg-red-50 dark:hover:bg-red-900/20 transition-all cursor-pointer"
              title="Logout"
            >
              <svg className="w-5 h-5 mr-2" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17 16l4-4m0 0l-4-4m4 4H7m6 4v1a3 3 0 01-3 3H6a3 3 0 01-3-3V7a3 3 0 013-3h4a3 3 0 013 3v1" />
              </svg>
              Logout
            </button>
          </>
        }
      />

      <div className="max-w-7xl mx-auto py-8 sm:px-6 lg:px-8">
        <div className="px-4 sm:px-0">
          {isLoading ? (
            <div className="text-center py-12">
              <p className="text-gray-600 dark:text-gray-400">Carregando...</p>
            </div>
          ) : (
            <>
              {/* Unified Settings & Wishlist Config */}
              {wishlist && (
                <div className="mb-6 bg-white dark:bg-gray-800 rounded-lg shadow-sm border border-gray-200 dark:border-gray-700 overflow-hidden">
                  <div className="p-5 border-b border-gray-200 dark:border-gray-700 flex items-center justify-between">
                    <h2 className="text-xl font-bold text-gray-900 dark:text-white">Configurações</h2>
                    {!isEditingWishlist && (
                      <button
                        onClick={startEditingWishlist}
                        className="px-4 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-300 hover:bg-gray-50 dark:hover:bg-gray-700 text-sm cursor-pointer"
                      >
                        Editar
                      </button>
                    )}
                  </div>
                  <div className="p-5">
                    {isEditingWishlist ? (
                      <form onSubmit={handleUpdateWishlist} className="space-y-4">
                        {editError && (
                          <div className="p-3 bg-red-50 dark:bg-red-900/20 text-red-800 dark:text-red-400 rounded-lg text-base">
                            {editError}
                          </div>
                        )}
                        <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
                          <div>
                            <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                              Título do site *
                            </label>
                            <input
                              type="text"
                              required
                              value={editForm.siteTitle}
                              onChange={(e) => setEditForm((prev) => ({ ...prev, siteTitle: e.target.value }))}
                              className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg focus:outline-none focus:ring-2 focus:ring-indigo-500 dark:bg-gray-700 dark:text-white"
                            />
                          </div>
                          <div>
                            <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                              Nome da lista *
                            </label>
                            <input
                              type="text"
                              required
                              value={editForm.name}
                              onChange={(e) => setEditForm((prev) => ({ ...prev, name: e.target.value }))}
                              className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg focus:outline-none focus:ring-2 focus:ring-indigo-500 dark:bg-gray-700 dark:text-white"
                            />
                          </div>
                        </div>
                        <div>
                          <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                            Mensagem de boas-vindas
                          </label>
                          <textarea
                            value={editForm.homepageSubtext}
                            onChange={(e) => setEditForm((prev) => ({ ...prev, homepageSubtext: e.target.value }))}
                            className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg focus:outline-none focus:ring-2 focus:ring-indigo-500 dark:bg-gray-700 dark:text-white"
                            rows={2}
                          />
                        </div>
                        <div className="flex gap-6">
                          <label className="flex items-center gap-2 cursor-pointer select-none">
                            <input
                              type="checkbox"
                              className="w-4 h-4 rounded accent-indigo-600"
                              checked={editForm.claimingEnabled}
                              onChange={(e) => setEditForm((prev) => ({ ...prev, claimingEnabled: e.target.checked }))}
                            />
                            <span className="text-sm text-gray-700 dark:text-gray-300">Permitir reservas</span>
                          </label>
                          <label className="flex items-center gap-2 cursor-pointer select-none">
                            <input
                              type="checkbox"
                              className="w-4 h-4 rounded accent-indigo-600"
                              checked={editForm.showQuantity}
                              onChange={(e) => setEditForm((prev) => ({ ...prev, showQuantity: e.target.checked }))}
                            />
                            <span className="text-sm text-gray-700 dark:text-gray-300">Mostrar quantidade</span>
                          </label>
                        </div>
                        <div>
                          <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                            Descrição da lista
                          </label>
                          <textarea
                            value={editForm.description}
                            onChange={(e) => setEditForm((prev) => ({ ...prev, description: e.target.value }))}
                            className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg focus:outline-none focus:ring-2 focus:ring-indigo-500 dark:bg-gray-700 dark:text-white"
                            rows={2}
                          />
                        </div>
                        <div>
                          <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                            Preferências
                          </label>
                          <RichTextEditor
                            value={editForm.preferences}
                            onChange={(html) => setEditForm((prev) => ({ ...prev, preferences: html }))}
                            placeholder="Interesses e preferências gerais..."
                          />
                        </div>
                        <ImageUpload
                          currentImageUrl={editForm.imageUrl}
                          onImageChange={(url) => setEditForm((prev) => ({ ...prev, imageUrl: url }))}
                          onUploadStateChange={setIsWishlistImageUploading}
                          type="wishlist"
                          label="Imagem da Lista"
                        />
                        <div className="flex gap-3 justify-end">
                          <button
                            type="button"
                            onClick={() => setIsEditingWishlist(false)}
                            className="px-4 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-300 hover:bg-gray-50 dark:hover:bg-gray-700 cursor-pointer"
                          >
                            Cancelar
                          </button>
                          <button
                            type="submit"
                            disabled={isWishlistImageUploading}
                            className="px-4 py-2 bg-indigo-600 text-white rounded-lg hover:bg-indigo-700 disabled:opacity-50 cursor-pointer"
                          >
                            {isWishlistImageUploading ? 'Enviando...' : 'Salvar'}
                          </button>
                        </div>
                      </form>
                    ) : (
                      <div className="space-y-3">
                        <div className="flex items-start gap-4">
                          {wishlist.imageUrl && (
                            <img
                              src={wishlist.imageUrl}
                              alt={wishlist.name}
                              className="w-16 h-16 object-cover rounded border border-gray-200 dark:border-gray-600 flex-shrink-0"
                            />
                          )}
                          <div className="flex-1 grid grid-cols-1 md:grid-cols-2 gap-x-6 gap-y-2">
                            <div>
                              <p className="text-xs font-medium text-gray-500 dark:text-gray-400">Título do site</p>
                              <p className="text-sm text-gray-900 dark:text-white">{settings.siteTitle}</p>
                            </div>
                            <div>
                              <p className="text-xs font-medium text-gray-500 dark:text-gray-400">Nome da lista</p>
                              <p className="text-sm text-gray-900 dark:text-white">{wishlist.name}</p>
                            </div>
                            {settings.homepageSubtext && (
                              <div className="md:col-span-2">
                                <p className="text-xs font-medium text-gray-500 dark:text-gray-400">Mensagem de boas-vindas</p>
                                <p className="text-sm text-gray-900 dark:text-white">{settings.homepageSubtext}</p>
                              </div>
                            )}
                            {wishlist.description && (
                              <div className="md:col-span-2">
                                <p className="text-xs font-medium text-gray-500 dark:text-gray-400">Descrição</p>
                                <p className="text-sm text-gray-900 dark:text-white">{wishlist.description}</p>
                              </div>
                            )}
                          </div>
                        </div>
                        <div className="flex gap-4 mt-1">
                          <span className={`text-xs px-2 py-0.5 rounded-full font-medium ${settings.claimingEnabled ? 'bg-green-100 dark:bg-green-900/30 text-green-700 dark:text-green-400' : 'bg-red-100 dark:bg-red-900/30 text-red-700 dark:text-red-400'}`}>
                            Reservas {settings.claimingEnabled ? 'ativas' : 'desativadas'}
                          </span>
                          <span className={`text-xs px-2 py-0.5 rounded-full font-medium ${settings.showQuantity ? 'bg-green-100 dark:bg-green-900/30 text-green-700 dark:text-green-400' : 'bg-yellow-100 dark:bg-yellow-900/30 text-yellow-700 dark:text-yellow-400'}`}>
                            Quantidade {settings.showQuantity ? 'visível' : 'oculta'}
                          </span>
                        </div>
                        {adminToken && (
                          <div className="mt-4 pt-4 border-t border-gray-200 dark:border-gray-700">
                            <p className="text-xs font-medium text-gray-500 dark:text-gray-400 mb-2">Link de acesso admin</p>
                            <div className="flex items-center gap-2">
                              <code className="flex-1 text-xs bg-gray-100 dark:bg-gray-700 text-gray-700 dark:text-gray-300 px-3 py-2 rounded truncate">
                                {`${typeof window !== 'undefined' ? window.location.origin : ''}/?adm=${adminToken}`}
                              </code>
                              <button
                                onClick={copyAdminLink}
                                className="flex-shrink-0 px-3 py-2 text-xs font-medium rounded border border-gray-300 dark:border-gray-600 text-gray-700 dark:text-gray-300 hover:bg-gray-50 dark:hover:bg-gray-700 transition-colors cursor-pointer"
                              >
                                {linkCopied ? 'Copiado!' : 'Copiar'}
                              </button>
                            </div>
                          </div>
                        )}
                      </div>
                    )}
                  </div>
                </div>
              )}

              {/* Items Section */}
              {wishlist && (
                <div className="mb-6">
                  <div className="flex items-center justify-between mb-4">
                    <h2 className="text-2xl font-bold text-gray-900 dark:text-white">
                      Itens ({items.length})
                    </h2>
                    <button
                      onClick={() => {
                        setShowAddItemForm(true);
                        setNewItemError('');
                      }}
                      className="inline-flex items-center px-6 py-3 border border-transparent text-base font-semibold rounded-lg text-white bg-indigo-600 hover:bg-indigo-700 shadow-md hover:shadow-lg transition-all cursor-pointer"
                    >
                      + Adicionar Item
                    </button>
                  </div>

                  {/* Add Item Form */}
                  {showAddItemForm && (
                    <ItemForm
                      mode="create"
                      onSubmit={handleCreateItem}
                      onCancel={() => {
                        setShowAddItemForm(false);
                        setNewItemError('');
                      }}
                      error={newItemError}
                    />
                  )}

                  {items.length === 0 && !showAddItemForm ? (
                    <div className="text-center py-12 bg-white dark:bg-gray-800 rounded-lg border border-gray-200 dark:border-gray-700">
                      <p className="text-gray-500 dark:text-gray-400 mb-6 text-lg">
                        Nenhum item ainda
                      </p>
                      <button
                        onClick={() => {
                          setShowAddItemForm(true);
                          setNewItemError('');
                        }}
                        className="inline-flex items-center px-6 py-3 border border-transparent text-base font-semibold rounded-lg text-white bg-indigo-600 hover:bg-indigo-700 shadow-md hover:shadow-lg transition-all cursor-pointer"
                      >
                        Adicionar Primeiro Item
                      </button>
                    </div>
                  ) : (
                    <div className="space-y-3">
                      {items.map((item, index) => (
                        <div key={item.id}>
                          {editingItemId === item.id ? (
                            <ItemForm
                              mode="edit"
                              item={editingItem}
                              onSubmit={handleUpdateItem}
                              onCancel={() => setEditingItemId(null)}
                            />
                          ) : (
                            <ItemCard
                              item={item}
                              onEdit={() => setEditingItemId(item.id)}
                              onDelete={() => handleDeleteItem(item.id)}
                              onMoveUp={() => handleMoveItemUp(item.id)}
                              onMoveDown={() => handleMoveItemDown(item.id)}
                              isFirst={index === 0}
                              isLast={index === items.length - 1}
                            />
                          )}
                        </div>
                      ))}
                    </div>
                  )}
                </div>
              )}

              {!wishlist && !isLoading && (
                <div className="text-center py-12 bg-white dark:bg-gray-800 rounded-lg border border-gray-200 dark:border-gray-700">
                  <p className="text-gray-500 dark:text-gray-400 text-lg">
                    Nenhuma lista encontrada no banco de dados.
                  </p>
                </div>
              )}
            </>
          )}
        </div>
      </div>
    </div>
  );
}