"use client";

import { useState } from "react";
import { useRouter } from "next/navigation";
import Link from "next/link";
import { login } from "@/lib/api";
import { useAuth } from "@/lib/auth";

export default function LoginPage() {
  const [email, setEmail] = useState("");
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState("");
  const { setAuth } = useAuth();
  const router = useRouter();

  async function handleSubmit(e: React.FormEvent) {
    e.preventDefault();
    if (!email.trim()) {
      setError("Zadejte email");
      return;
    }
    setLoading(true);
    setError("");
    try {
      const result = await login({ email: email.trim() });
      setAuth(result.token, result.user);
      router.push("/tasks");
    } catch (err) {
      setError(err instanceof Error ? err.message : "Chyba prihlaseni");
    } finally {
      setLoading(false);
    }
  }

  return (
    <div className="min-h-[70vh] flex items-center justify-center">
      <div className="w-full max-w-sm">
        <div className="bg-white dark:bg-gray-900 border border-gray-200 dark:border-gray-700 rounded-2xl p-6 shadow-sm">
          <h1 className="text-2xl font-bold text-center mb-6">Prihlaseni</h1>

          {error && (
            <div className="bg-red-50 dark:bg-red-900/20 border border-red-200 dark:border-red-800 text-red-700 dark:text-red-300 px-4 py-3 rounded-lg text-sm mb-4">
              {error}
            </div>
          )}

          <form onSubmit={handleSubmit} className="space-y-4">
            <div>
              <label className="block text-sm font-medium mb-1">Email</label>
              <input
                type="email"
                value={email}
                onChange={(e) => setEmail(e.target.value)}
                className="w-full px-3 py-2.5 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 focus:ring-2 focus:ring-blue-500 focus:border-transparent outline-none"
                placeholder="vas@email.cz"
                autoFocus
                autoComplete="email"
              />
            </div>

            <button
              type="submit"
              disabled={loading}
              className="w-full bg-blue-600 hover:bg-blue-700 text-white font-medium py-2.5 px-4 rounded-lg transition-colors disabled:opacity-50"
            >
              {loading ? "Prihlasuji..." : "Prihlasit se"}
            </button>
          </form>

          <p className="text-center text-sm text-muted mt-4">
            Nemate ucet?{" "}
            <Link href="/register" className="text-blue-600 hover:underline">
              Registrovat se
            </Link>
          </p>
        </div>
      </div>
    </div>
  );
}