import { useState, useEffect } from 'react';
import { Search, Filter, Box, Plus, Edit2, Trash2, Image as ImageIcon, X } from 'lucide-react';
import { toast } from 'react-hot-toast';
import api from '../services/api';
import Spinner from '../components/ui/Spinner';
import Pagination from '../components/ui/Pagination';
import MediaSelector from '../components/ui/MediaSelector';

export default function Products() {
  const [products, setProducts] = useState<any[]>([]);
  const [categories, setCategories] = useState<any[]>([]);
  const [isLoading, setIsLoading] = useState(true);
  
  // Filters
  const [search, setSearch] = useState('');
  const [categoryFilter, setCategoryFilter] = useState('');
  const [page, setPage] = useState(1);
  const [totalPages, setTotalPages] = useState(1);
  const limit = 10;

  // Modal State
  const [isModalOpen, setIsModalOpen] = useState(false);
  const [isMediaSelectorOpen, setIsMediaSelectorOpen] = useState(false);
  const [editingProduct, setEditingProduct] = useState<any>(null);
  const [activeTab, setActiveTab] = useState('general');

  const [formData, setFormData] = useState({
    artNo: '',
    name: '',
    scientificTagline: '',
    description: '',
    shortDescription: '',
    categoryId: '',
    priceValue: 0,
    priceDisplay: '',
    unit: '',
    packageSize: 0,
    dosageLogic: '',
    suitableFor: 'سگ و گربه',
    imageUrl: '',
    metaTitle: '',
    metaDescription: '',
    keywords: '',
    canonicalUrl: '',
    slug: ''
  });

  const fetchData = async () => {
    try {
      setIsLoading(true);
      // Fetch products first
      const prodRes = await api.get('/admin/products', { params: { page, limit, search, categoryId: categoryFilter } });
      if (prodRes.data?.data) {
        setProducts(prodRes.data.data);
        setTotalPages(prodRes.data.meta?.lastPage || 1);
      }

      // Fetch categories separately so it doesn't break products
      try {
        const catRes = await api.get('/admin/categories');
        if (catRes.data?.data) {
          setCategories(catRes.data.data);
        } else if (Array.isArray(catRes.data)) {
          setCategories(catRes.data);
        }
      } catch (err) {
        console.warn('Could not fetch categories', err);
      }
    } catch (err: any) {
      console.error(err);
      toast.error('خطا در دریافت لیست محصولات: ' + (err.response?.data?.message || err.message));
    } finally {
      setIsLoading(false);
    }
  };

  useEffect(() => {
    const timer = setTimeout(() => {
      fetchData();
    }, 500);
    return () => clearTimeout(timer);
  }, [search, categoryFilter, page]);

  const openModal = (product: any = null) => {
    if (product) {
      setEditingProduct(product);
      setFormData({
        artNo: product.artNo,
        name: product.name,
        scientificTagline: product.scientificTagline || '',
        description: product.description || '',
        shortDescription: product.shortDescription || '',
        categoryId: product.categoryId || '',
        priceValue: Number(product.priceValue),
        priceDisplay: product.priceDisplay || '',
        unit: product.unit || '',
        packageSize: Number(product.packageSize),
        dosageLogic: product.dosageLogic || '',
        suitableFor: product.suitableFor || 'سگ و گربه',
        imageUrl: product.imageUrl || '',
        metaTitle: product.metaTitle || '',
        metaDescription: product.metaDescription || '',
        keywords: product.keywords || '',
        canonicalUrl: product.canonicalUrl || '',
        slug: product.slug || ''
      });
    } else {
      setEditingProduct(null);
      setFormData({
        artNo: '', name: '', scientificTagline: '', description: '', shortDescription: '', categoryId: '',
        priceValue: 0, priceDisplay: '', unit: '', packageSize: 0, dosageLogic: '', suitableFor: 'سگ و گربه',
        imageUrl: '', metaTitle: '', metaDescription: '', keywords: '', canonicalUrl: '', slug: ''
      });
    }
    setActiveTab('general');
    setIsModalOpen(true);
  };

  const handleSave = async (e: React.FormEvent) => {
    e.preventDefault();
    try {
      if (editingProduct) {
        await api.put(`/admin/products/${editingProduct.id}`, formData);
      } else {
        await api.post('/admin/products', formData);
      }
      setIsModalOpen(false);
      fetchData();
    } catch (error) {
      console.error('Save failed', error);
      alert('خطا در ذخیره محصول');
    }
  };

  const handleDelete = async (id: string) => {
    if (!window.confirm('آیا از حذف این محصول مطمئن هستید؟')) return;
    try {
      await api.delete(`/admin/products/${id}`);
      fetchData();
    } catch (error) {
      console.error('Delete failed', error);
    }
  };

  return (
    <div className="space-y-6">
      <div className="flex flex-col sm:flex-row justify-between gap-4">
        <div>
          <h2 className="text-2xl font-black text-gray-900 flex items-center gap-2">
            <Box className="w-6 h-6 text-purple-600" />
            مدیریت محصولات
          </h2>
          <p className="text-gray-500 font-medium mt-1">افزودن و ویرایش پیشرفته محصولات با تنظیمات سئو</p>
        </div>
        <button 
          onClick={() => openModal()}
          className="bg-purple-600 hover:bg-purple-700 text-white px-5 py-2.5 rounded-xl flex items-center gap-2 font-bold transition-all shadow-md shadow-purple-200"
        >
          <Plus className="w-5 h-5" />
          محصول جدید
        </button>
      </div>

      <div className="bg-white p-4 rounded-2xl shadow-sm border border-gray-200 flex flex-col sm:flex-row gap-4">
        <div className="relative flex-1">
          <Search className="w-5 h-5 absolute right-4 top-1/2 -translate-y-1/2 text-gray-400" />
          <input 
            type="text" 
            placeholder="جستجو در نام و کد محصول..." 
            value={search}
            onChange={(e) => { setSearch(e.target.value); setPage(1); }}
            className="w-full pl-4 pr-12 py-3 rounded-xl border border-gray-200 focus:border-purple-500 focus:ring-2 focus:ring-purple-200 outline-none transition-all"
          />
        </div>
        <div className="relative w-full sm:w-64">
          <Filter className="w-5 h-5 absolute right-4 top-1/2 -translate-y-1/2 text-gray-400" />
          <select 
            value={categoryFilter}
            onChange={(e) => { setCategoryFilter(e.target.value); setPage(1); }}
            className="w-full pl-4 pr-12 py-3 rounded-xl border border-gray-200 focus:border-purple-500 focus:ring-2 focus:ring-purple-200 outline-none transition-all appearance-none"
          >
            <option value="">همه دسته‌بندی‌ها</option>
            {categories.map(c => <option key={c.id} value={c.id}>{c.name}</option>)}
          </select>
        </div>
      </div>

      <div className="bg-white rounded-2xl shadow-sm border border-gray-200 overflow-hidden">
        <div className="overflow-x-auto">
          <table className="w-full text-right">
            <thead className="bg-gray-50 border-b border-gray-100">
              <tr>
                <th className="py-4 px-6 text-sm font-bold text-gray-500">تصویر</th>
                <th className="py-4 px-6 text-sm font-bold text-gray-500">کد (Art No)</th>
                <th className="py-4 px-6 text-sm font-bold text-gray-500">نام محصول</th>
                <th className="py-4 px-6 text-sm font-bold text-gray-500">دسته‌بندی</th>
                <th className="py-4 px-6 text-sm font-bold text-gray-500">موجودی / قیمت</th>
                <th className="py-4 px-6 text-sm font-bold text-gray-500 w-24">عملیات</th>
              </tr>
            </thead>
            <tbody className="divide-y divide-gray-100">
              {isLoading ? (
                <tr>
                  <td colSpan={6} className="py-12 text-center">
                    <Spinner size="lg" className="mx-auto text-purple-600" />
                  </td>
                </tr>
              ) : products.length === 0 ? (
                <tr>
                  <td colSpan={6} className="py-12 text-center text-gray-500 font-medium">محصولی یافت نشد</td>
                </tr>
              ) : (
                products.map((product) => (
                  <tr key={product.id} className="hover:bg-gray-50/50 transition-colors">
                    <td className="py-3 px-6">
                      {product.imageUrl ? (
                        <img src={product.imageUrl.startsWith('http') ? product.imageUrl : `http://localhost:4001${product.imageUrl}`} alt={product.name} className="w-12 h-12 rounded-xl object-cover border border-gray-200" />
                      ) : (
                        <div className="w-12 h-12 rounded-xl bg-gray-100 flex items-center justify-center text-gray-400">
                          <ImageIcon className="w-5 h-5" />
                        </div>
                      )}
                    </td>
                    <td className="py-4 px-6 text-gray-500 font-mono text-sm">{product.artNo}</td>
                    <td className="py-4 px-6 font-bold text-gray-900">{product.name}</td>
                    <td className="py-4 px-6 text-gray-600 text-sm">{product.category?.name || 'بدون دسته'}</td>
                    <td className="py-4 px-6">
                      <div className="flex flex-col">
                        <span className="font-bold text-gray-900">{Number(product.priceValue).toLocaleString()} تومان</span>
                        <span className="text-xs text-gray-500">{product.packageSize} موجودی</span>
                      </div>
                    </td>
                    <td className="py-4 px-6">
                      <div className="flex items-center gap-2">
                        <button onClick={() => openModal(product)} className="p-2 text-blue-600 hover:bg-blue-50 rounded-lg transition-colors">
                          <Edit2 className="w-4 h-4" />
                        </button>
                        <button onClick={() => handleDelete(product.id)} className="p-2 text-red-600 hover:bg-red-50 rounded-lg transition-colors">
                          <Trash2 className="w-4 h-4" />
                        </button>
                      </div>
                    </td>
                  </tr>
                ))
              )}
            </tbody>
          </table>
        </div>
        {!isLoading && totalPages > 1 && (
          <div className="p-4 border-t border-gray-100 flex justify-center bg-gray-50/50">
            <Pagination currentPage={page} totalPages={totalPages} onPageChange={setPage} />
          </div>
        )}
      </div>

      {isModalOpen && (
        <div className="fixed inset-0 z-50 flex items-center justify-center p-4 bg-gray-900/60 backdrop-blur-sm">
          <div className="bg-white rounded-2xl w-full max-w-4xl max-h-[90vh] flex flex-col shadow-2xl animate-in zoom-in duration-200">
            <div className="px-6 py-4 border-b border-gray-100 flex justify-between items-center bg-gray-50/50">
              <h3 className="text-xl font-bold text-gray-900">
                {editingProduct ? 'ویرایش پیشرفته محصول' : 'افزودن محصول جدید'}
              </h3>
              <button onClick={() => setIsModalOpen(false)} className="text-gray-400 hover:text-red-500 transition-colors">
                <X className="w-6 h-6" />
              </button>
            </div>
            
            <div className="flex border-b border-gray-100 px-6 pt-2 gap-4">
              {[
                { id: 'general', label: 'اطلاعات پایه' },
                { id: 'pricing', label: 'موجودی و قیمت' },
                { id: 'seo', label: 'سئو (SEO)' },
                { id: 'media', label: 'تصاویر' }
              ].map(tab => (
                <button
                  key={tab.id}
                  type="button"
                  onClick={() => setActiveTab(tab.id)}
                  className={`pb-3 px-2 text-sm font-bold border-b-2 transition-colors ${activeTab === tab.id ? 'border-purple-600 text-purple-700' : 'border-transparent text-gray-500 hover:text-gray-700'}`}
                >
                  {tab.label}
                </button>
              ))}
            </div>

            <div className="p-6 overflow-y-auto flex-1 bg-gray-50/30">
              <form id="productForm" onSubmit={handleSave} className="space-y-6">
                
                {/* General Tab */}
                <div className={activeTab === 'general' ? 'block space-y-4' : 'hidden'}>
                  <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">کد محصول (Art No) *</label>
                      <input required type="text" value={formData.artNo} onChange={(e) => setFormData({...formData, artNo: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none font-mono" dir="ltr" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">نام محصول *</label>
                      <input required type="text" value={formData.name} onChange={(e) => setFormData({...formData, name: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" />
                    </div>
                    <div className="space-y-2 md:col-span-2">
                      <label className="text-sm font-bold text-gray-700">شعار علمی (Tagline)</label>
                      <input type="text" value={formData.scientificTagline} onChange={(e) => setFormData({...formData, scientificTagline: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">دسته‌بندی *</label>
                      <select required value={formData.categoryId} onChange={(e) => setFormData({...formData, categoryId: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none bg-white">
                        <option value="">انتخاب کنید</option>
                        {categories.map(c => <option key={c.id} value={c.id}>{c.name}</option>)}
                      </select>
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">مناسب برای</label>
                      <select value={formData.suitableFor} onChange={(e) => setFormData({...formData, suitableFor: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none bg-white">
                        <option value="سگ">سگ</option>
                        <option value="گربه">گربه</option>
                        <option value="سگ و گربه">سگ و گربه</option>
                      </select>
                    </div>
                    <div className="space-y-2 md:col-span-2">
                      <label className="text-sm font-bold text-gray-700">توضیح کوتاه</label>
                      <textarea rows={2} value={formData.shortDescription} onChange={(e) => setFormData({...formData, shortDescription: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none"></textarea>
                    </div>
                    <div className="space-y-2 md:col-span-2">
                      <label className="text-sm font-bold text-gray-700">توضیحات کامل</label>
                      <textarea rows={5} value={formData.description} onChange={(e) => setFormData({...formData, description: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none"></textarea>
                    </div>
                    <div className="space-y-2 md:col-span-2">
                      <label className="text-sm font-bold text-gray-700">منطق دوز مصرفی (Dosage Logic)</label>
                      <textarea rows={2} value={formData.dosageLogic} onChange={(e) => setFormData({...formData, dosageLogic: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none"></textarea>
                    </div>
                  </div>
                </div>

                {/* Pricing Tab */}
                <div className={activeTab === 'pricing' ? 'block space-y-4' : 'hidden'}>
                  <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">قیمت (تومان) *</label>
                      <input required type="number" min="0" value={formData.priceValue} onChange={(e) => setFormData({...formData, priceValue: Number(e.target.value)})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" dir="ltr" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">نمایش قیمت (متنی) *</label>
                      <input required type="text" placeholder="مثال: ۸۵۰,۰۰۰ تومان" value={formData.priceDisplay} onChange={(e) => setFormData({...formData, priceDisplay: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">موجودی *</label>
                      <input required type="number" min="0" value={formData.packageSize} onChange={(e) => setFormData({...formData, packageSize: Number(e.target.value)})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" dir="ltr" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">واحد (Unit) *</label>
                      <input required type="text" placeholder="عدد، گرم، میلی‌لیتر" value={formData.unit} onChange={(e) => setFormData({...formData, unit: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" />
                    </div>
                  </div>
                </div>

                {/* SEO Tab */}
                <div className={activeTab === 'seo' ? 'block space-y-4' : 'hidden'}>
                  <div className="grid grid-cols-1 gap-4">
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">نامک (Slug) محصول</label>
                      <input type="text" value={formData.slug} onChange={(e) => setFormData({...formData, slug: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" dir="ltr" placeholder="مثال: canhydrox-gag" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">عنوان متا (Meta Title)</label>
                      <input type="text" value={formData.metaTitle} onChange={(e) => setFormData({...formData, metaTitle: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">توضیحات متا (Meta Description)</label>
                      <textarea rows={3} value={formData.metaDescription} onChange={(e) => setFormData({...formData, metaDescription: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none"></textarea>
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">کلمات کلیدی (با کاما جدا کنید)</label>
                      <input type="text" value={formData.keywords} onChange={(e) => setFormData({...formData, keywords: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none" />
                    </div>
                    <div className="space-y-2">
                      <label className="text-sm font-bold text-gray-700">آدرس کانونی (Canonical URL)</label>
                      <input type="text" value={formData.canonicalUrl} onChange={(e) => setFormData({...formData, canonicalUrl: e.target.value})} className="w-full px-4 py-3 rounded-xl border border-gray-200 focus:border-purple-500 outline-none font-mono text-sm" dir="ltr" />
                    </div>
                  </div>
                </div>

                {/* Media Tab */}
                <div className={activeTab === 'media' ? 'block space-y-4' : 'hidden'}>
                  <div className="flex flex-col items-center justify-center p-8 border-2 border-dashed border-gray-200 rounded-2xl bg-white">
                    {formData.imageUrl ? (
                      <div className="w-full flex flex-col items-center">
                        <div className="relative group">
                          <img src={formData.imageUrl.startsWith('http') ? formData.imageUrl : `http://localhost:4001${formData.imageUrl}`} alt="product" className="max-w-xs h-48 object-cover rounded-xl shadow-md" />
                          <div className="absolute inset-0 bg-black/50 opacity-0 group-hover:opacity-100 transition-opacity rounded-xl flex items-center justify-center gap-3">
                            <button type="button" onClick={() => setIsMediaSelectorOpen(true)} className="bg-white text-gray-800 px-4 py-2 rounded-lg font-bold text-sm">تغییر عکس</button>
                          </div>
                        </div>
                        <div className="mt-4 text-center" dir="ltr">
                          <p className="text-xs text-gray-500 font-mono bg-gray-100 px-4 py-2 rounded-lg inline-block">
                            {formData.imageUrl.split('/').pop()}
                          </p>
                        </div>
                        <p className="text-[11px] text-gray-400 mt-2">برای تغییر عکس، روی تصویر کلیک کنید یا دکمه زیر را بزنید</p>
                        <button type="button" onClick={() => setIsMediaSelectorOpen(true)} className="mt-3 bg-purple-100 text-purple-700 hover:bg-purple-200 px-6 py-2 rounded-xl font-bold transition-colors text-sm">
                          انتخاب از گالری رسانه
                        </button>
                      </div>
                    ) : (
                      <>
                        <div className="w-16 h-16 bg-gray-100 rounded-full flex items-center justify-center text-gray-400 mb-4">
                          <ImageIcon className="w-8 h-8" />
                        </div>
                        <p className="text-gray-500 font-medium mb-4">هیچ تصویری انتخاب نشده است</p>
                        <p className="text-xs text-gray-400 mb-4">از گالری رسانه تصویر انتخاب کنید یا با Ctrl+V از کلیپ‌بورد بچسبانید</p>
                        <button type="button" onClick={() => setIsMediaSelectorOpen(true)} className="bg-purple-100 text-purple-700 hover:bg-purple-200 px-6 py-2 rounded-xl font-bold transition-colors">
                          انتخاب از گالری رسانه
                        </button>
                      </>
                    )}
                  </div>
                </div>

              </form>
            </div>
            
            <div className="p-4 border-t border-gray-100 bg-gray-50 flex justify-end gap-3 rounded-b-2xl">
              <button type="button" onClick={() => setIsModalOpen(false)} className="px-5 py-2.5 rounded-xl font-bold text-gray-600 hover:bg-gray-200 transition-colors">
                انصراف
              </button>
              <button type="submit" form="productForm" className="bg-purple-600 hover:bg-purple-700 text-white px-8 py-2.5 rounded-xl font-bold transition-all shadow-md shadow-purple-200">
                ذخیره محصول
              </button>
            </div>
          </div>
        </div>
      )}

      {/* Media Selector Modal */}
      <MediaSelector 
        isOpen={isMediaSelectorOpen} 
        onClose={() => setIsMediaSelectorOpen(false)} 
        onSelect={(url) => setFormData({...formData, imageUrl: url})} 
        selectedUrl={formData.imageUrl.startsWith('http') ? formData.imageUrl : formData.imageUrl ? `http://localhost:4001${formData.imageUrl}` : undefined}
      />
    </div>
  );
}