'use client';

import { useState, useEffect } from 'react';
import Link from 'next/link';
import { filamentService, productService } from '@/src/services/api';
import { Filament } from '@/src/types/filament';
import { Product } from '@/src/types/product';

interface StatsCard {
  label: string;
  value: number | string;
  colorHex: string;
  href?: string;
}

export default function AdminOverview() {
  const [filaments, setFilaments] = useState<(Filament & { id: string })[]>([]);
  const [products, setProducts] = useState<Product[]>([]);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    const fetchData = async () => {
      try {
        const [filamentData, productData] = await Promise.all([
          filamentService.getAll(),
          productService.getAll().catch(() => []),
        ]);
        setFilaments(filamentData);
        setProducts(productData);
      } catch (error) {
        console.error('Error loading overview data:', error);
      } finally {
        setLoading(false);
      }
    };
    fetchData();
  }, []);

  const lowStockFilaments = filaments.filter(f => f.kolicina <= 2 && f.kolicina > 0);
  const outOfStockFilaments = filaments.filter(f => f.kolicina === 0);
  const lowStockProducts = products.filter(p => p.stock <= 2 && p.stock > 0);
  const outOfStockProducts = products.filter(p => p.stock === 0);
  const activeSales = filaments.filter(f => f.sale_active).length + products.filter(p => p.sale_active).length;

  const statsCards: StatsCard[] = [
    { label: 'Ukupno filamenata', value: filaments.length, colorHex: '#3b82f6', href: '/upadaj/dashboard/filamenti' },
    { label: 'Ukupno proizvoda', value: products.length, colorHex: '#22c55e', href: '/upadaj/dashboard/stampaci' },
    { label: 'Nisko stanje', value: lowStockFilaments.length + lowStockProducts.length, colorHex: '#f59e0b' },
    { label: 'Aktivni popusti', value: activeSales, colorHex: '#a855f7', href: '/upadaj/dashboard/prodaja' },
  ];

  if (loading) {
    return (
      <div className="flex items-center justify-center h-64">
        <div className="flex flex-col items-center gap-4">
          <div className="w-10 h-10 border-4 border-blue-500 border-t-transparent rounded-full animate-spin" />
          <p className="text-white/40 text-sm">Ucitavanje...</p>
        </div>
      </div>
    );
  }

  return (
    <div className="space-y-8">
      {/* Page title */}
      <div>
        <h1
          className="text-2xl font-black text-white tracking-tight"
          style={{ fontFamily: 'var(--font-display)' }}
        >
          Pregled
        </h1>
        <p className="text-white/40 mt-1 text-sm">Brzi pregled stanja inventara</p>
      </div>

      {/* Stats Cards */}
      <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4">
        {statsCards.map((card) => {
          const content = (
            <div
              key={card.label}
              className="rounded-2xl p-5 text-white"
              style={{
                background: `linear-gradient(135deg, ${card.colorHex}, ${card.colorHex}cc)`,
                boxShadow: `0 4px 20px ${card.colorHex}30`,
              }}
            >
              <p className="text-sm font-semibold opacity-80">{card.label}</p>
              <p
                className="text-3xl font-black mt-1"
                style={{ fontFamily: 'var(--font-display)' }}
              >
                {card.value}
              </p>
            </div>
          );
          return card.href ? (
            <Link key={card.label} href={card.href} className="hover:scale-[1.02] transition-transform">
              {content}
            </Link>
          ) : (
            <div key={card.label}>{content}</div>
          );
        })}
      </div>

      {/* Low Stock Alerts */}
      {(lowStockFilaments.length > 0 || outOfStockFilaments.length > 0 || lowStockProducts.length > 0 || outOfStockProducts.length > 0) && (
        <div className="bg-white/[0.04] border border-white/[0.06] rounded-2xl p-6">
          <h2
            className="text-lg font-bold text-white mb-4"
            style={{ fontFamily: 'var(--font-display)' }}
          >
            Upozorenja o stanju
          </h2>

          {/* Out of stock */}
          {(outOfStockFilaments.length > 0 || outOfStockProducts.length > 0) && (
            <div className="mb-4">
              <h3 className="text-sm font-semibold text-red-400 mb-2">
                Nema na stanju ({outOfStockFilaments.length + outOfStockProducts.length})
              </h3>
              <div className="space-y-1.5">
                {outOfStockFilaments.slice(0, 5).map(f => (
                  <div key={f.id} className="text-sm text-white/60 flex items-center gap-2">
                    <span className="w-2 h-2 rounded-full bg-red-500 shrink-0" />
                    {f.tip} {f.finish} - {f.boja}
                  </div>
                ))}
                {outOfStockProducts.slice(0, 5).map(p => (
                  <div key={p.id} className="text-sm text-white/60 flex items-center gap-2">
                    <span className="w-2 h-2 rounded-full bg-red-500 shrink-0" />
                    {p.name}
                  </div>
                ))}
                {(outOfStockFilaments.length + outOfStockProducts.length) > 10 && (
                  <p className="text-xs text-white/30">
                    ...i jos {outOfStockFilaments.length + outOfStockProducts.length - 10}
                  </p>
                )}
              </div>
            </div>
          )}

          {/* Low stock */}
          {(lowStockFilaments.length > 0 || lowStockProducts.length > 0) && (
            <div>
              <h3 className="text-sm font-semibold text-amber-400 mb-2">
                Nisko stanje ({lowStockFilaments.length + lowStockProducts.length})
              </h3>
              <div className="space-y-1.5">
                {lowStockFilaments.slice(0, 5).map(f => (
                  <div key={f.id} className="text-sm text-white/60 flex items-center gap-2">
                    <span className="w-2 h-2 rounded-full bg-amber-500 shrink-0" />
                    {f.tip} {f.finish} - {f.boja} (kolicina: {f.kolicina})
                  </div>
                ))}
                {lowStockProducts.slice(0, 5).map(p => (
                  <div key={p.id} className="text-sm text-white/60 flex items-center gap-2">
                    <span className="w-2 h-2 rounded-full bg-amber-500 shrink-0" />
                    {p.name} (stanje: {p.stock})
                  </div>
                ))}
                {(lowStockFilaments.length + lowStockProducts.length) > 10 && (
                  <p className="text-xs text-white/30">
                    ...i jos {lowStockFilaments.length + lowStockProducts.length - 10}
                  </p>
                )}
              </div>
            </div>
          )}
        </div>
      )}

      {/* Recent Activity */}
      <div className="bg-white/[0.04] border border-white/[0.06] rounded-2xl p-6">
        <h2
          className="text-lg font-bold text-white mb-4"
          style={{ fontFamily: 'var(--font-display)' }}
        >
          Poslednje dodano
        </h2>
        <div className="space-y-2.5">
          {[...filaments]
            .sort((a, b) => {
              const dateA = a.updated_at || a.created_at || '';
              const dateB = b.updated_at || b.created_at || '';
              return new Date(dateB).getTime() - new Date(dateA).getTime();
            })
            .slice(0, 5)
            .map(f => (
              <div key={f.id} className="flex items-center justify-between text-sm">
                <div className="flex items-center gap-3">
                  {f.boja_hex && (
                    <div
                      className="w-4 h-4 rounded-md border border-white/10"
                      style={{ backgroundColor: f.boja_hex }}
                    />
                  )}
                  <span className="text-white/70">{f.tip} {f.finish} - {f.boja}</span>
                </div>
                <span className="text-white/30 text-xs">
                  {f.updated_at
                    ? new Date(f.updated_at).toLocaleDateString('sr-RS')
                    : f.created_at
                    ? new Date(f.created_at).toLocaleDateString('sr-RS')
                    : '-'}
                </span>
              </div>
            ))}
          {filaments.length === 0 && (
            <p className="text-white/30 text-sm">Nema filamenata</p>
          )}
        </div>
      </div>

      {/* Quick Actions */}
      <div className="bg-white/[0.04] border border-white/[0.06] rounded-2xl p-6">
        <h2
          className="text-lg font-bold text-white mb-4"
          style={{ fontFamily: 'var(--font-display)' }}
        >
          Brze akcije
        </h2>
        <div className="flex flex-wrap gap-3">
          {[
            { href: '/upadaj/dashboard/filamenti', label: 'Dodaj filament', color: '#3b82f6' },
            { href: '/upadaj/dashboard/stampaci', label: 'Dodaj proizvod', color: '#22c55e' },
            { href: '/upadaj/dashboard/prodaja', label: 'Upravljaj popustima', color: '#a855f7' },
            { href: '/upadaj/dashboard/boje', label: 'Upravljaj bojama', color: '#ec4899' },
            { href: '/upadaj/dashboard/analitika', label: 'Analitika', color: '#14b8a6' },
          ].map(action => (
            <Link
              key={action.href}
              href={action.href}
              className="px-4 py-2.5 text-white rounded-xl text-sm font-semibold hover:scale-[1.03] transition-transform"
              style={{
                background: action.color,
                boxShadow: `0 2px 10px ${action.color}30`,
              }}
            >
              {action.label}
            </Link>
          ))}
        </div>
      </div>
    </div>
  );
}