"use client";

import { useSession, signOut } from "next-auth/react";
import { useState, useEffect, FormEvent } from "react";
import { useRouter } from "next/navigation";
import Link from "next/link";

const API_BASE_URL = process.env.NEXT_PUBLIC_API_BASE_URL || "http://localhost:8000/api/v1";

interface UserData {
  id: number;
  email: string;
  first_name: string;
  last_name: string;
  is_active: boolean;
  date_joined: string;
}

export default function ProfilePage() {
  const { data: session, status } = useSession();
  const router = useRouter();
  const [userData, setUserData] = useState<UserData | null>(null);
  const [formData, setFormData] = useState({
    first_name: "",
    last_name: "",
  });
  const [loading, setLoading] = useState(true);
  const [updating, setUpdating] = useState(false);
  const [error, setError] = useState("");
  const [success, setSuccess] = useState(false);

  useEffect(() => {
    if (status === "unauthenticated") {
      router.push("/auth/login");
    }
  }, [status, router]);

  useEffect(() => {
    const fetchUserData = async () => {
      if (!session?.accessToken) return;

      try {
        const response = await fetch(`${API_BASE_URL}/auth/users/me/`, {
          headers: {
            Authorization: `Bearer ${session.accessToken}`,
          },
        });

        if (response.ok) {
          const data = await response.json();
          setUserData(data);
          setFormData({
            first_name: data.first_name || "",
            last_name: data.last_name || "",
          });
        } else if (response.status === 401) {
          // Token expired, logout
          signOut({ callbackUrl: "/auth/login" });
        }
      } catch (err) {
        console.error("Error fetching user data:", err);
        setError("Kullanıcı bilgileri yüklenemedi.");
      } finally {
        setLoading(false);
      }
    };

    if (session?.accessToken) {
      fetchUserData();
    }
  }, [session]);

  const handleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    setFormData({
      ...formData,
      [e.target.name]: e.target.value,
    });
  };

  const handleSubmit = async (e: FormEvent<HTMLFormElement>) => {
    e.preventDefault();
    setError("");
    setSuccess(false);
    setUpdating(true);

    if (!session?.accessToken) return;

    try {
      const response = await fetch(`${API_BASE_URL}/auth/users/me/`, {
        method: "PATCH",
        headers: {
          "Content-Type": "application/json",
          Authorization: `Bearer ${session.accessToken}`,
        },
        body: JSON.stringify(formData),
      });

      if (response.ok) {
        const data = await response.json();
        setUserData(data);
        setSuccess(true);
        setTimeout(() => setSuccess(false), 3000);
      } else if (response.status === 401) {
        signOut({ callbackUrl: "/auth/login" });
      } else {
        const data = await response.json();
        setError(data.detail || "Profil güncellenemedi.");
      }
    } catch (err) {
      setError("Bir hata oluştu. Lütfen tekrar deneyin.");
      console.error("Update profile error:", err);
    } finally {
      setUpdating(false);
    }
  };

  const handleLogout = () => {
    signOut({ callbackUrl: "/auth/login" });
  };

  if (status === "loading" || loading) {
    return (
      <div className="min-h-screen flex items-center justify-center bg-gray-50">
        <div className="text-center">
          <div className="inline-block animate-spin rounded-full h-12 w-12 border-b-2 border-blue-600"></div>
          <p className="mt-4 text-gray-600">Yükleniyor...</p>
        </div>
      </div>
    );
  }

  if (!session) {
    return null;
  }

  return (
    <div className="min-h-screen bg-gray-50 py-12 px-4 sm:px-6 lg:px-8">
      <div className="max-w-3xl mx-auto">
        <div className="bg-white shadow rounded-lg">
          {/* Header */}
          <div className="px-4 py-5 sm:px-6 border-b border-gray-200">
            <div className="flex items-center justify-between">
              <div>
                <h1 className="text-2xl font-bold text-gray-900">Profil</h1>
                <p className="mt-1 text-sm text-gray-500">
                  Hesap bilgilerinizi görüntüleyin ve güncelleyin.
                </p>
              </div>
              <Link
                href="/dashboard"
                className="inline-flex items-center px-4 py-2 border border-gray-300 shadow-sm text-sm font-medium rounded-md text-gray-700 bg-white hover:bg-gray-50"
              >
                Dashboard
              </Link>
            </div>
          </div>

          {/* User Info */}
          {userData && (
            <div className="px-4 py-5 sm:p-6">
              <dl className="grid grid-cols-1 gap-x-4 gap-y-6 sm:grid-cols-2">
                <div className="sm:col-span-2">
                  <dt className="text-sm font-medium text-gray-500">Email</dt>
                  <dd className="mt-1 text-sm text-gray-900">{userData.email}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-gray-500">Üyelik Tarihi</dt>
                  <dd className="mt-1 text-sm text-gray-900">
                    {new Date(userData.date_joined).toLocaleDateString("tr-TR", {
                      year: "numeric",
                      month: "long",
                      day: "numeric",
                    })}
                  </dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-gray-500">Hesap Durumu</dt>
                  <dd className="mt-1">
                    <span
                      className={`inline-flex px-2 py-1 text-xs font-semibold rounded-full ${
                        userData.is_active
                          ? "bg-green-100 text-green-800"
                          : "bg-red-100 text-red-800"
                      }`}
                    >
                      {userData.is_active ? "Aktif" : "Pasif"}
                    </span>
                  </dd>
                </div>
              </dl>
            </div>
          )}

          {/* Update Form */}
          <div className="px-4 py-5 sm:p-6 border-t border-gray-200">
            <h2 className="text-lg font-medium text-gray-900 mb-4">
              Profil Bilgilerini Güncelle
            </h2>
            <form onSubmit={handleSubmit} className="space-y-4">
              <div className="grid grid-cols-1 gap-4 sm:grid-cols-2">
                <div>
                  <label
                    htmlFor="first_name"
                    className="block text-sm font-medium text-gray-700 mb-1"
                  >
                    Ad
                  </label>
                  <input
                    type="text"
                    name="first_name"
                    id="first_name"
                    className="appearance-none block w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm placeholder-gray-400 focus:outline-none focus:ring-blue-500 focus:border-blue-500 sm:text-sm"
                    value={formData.first_name}
                    onChange={handleChange}
                  />
                </div>
                <div>
                  <label
                    htmlFor="last_name"
                    className="block text-sm font-medium text-gray-700 mb-1"
                  >
                    Soyad
                  </label>
                  <input
                    type="text"
                    name="last_name"
                    id="last_name"
                    className="appearance-none block w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm placeholder-gray-400 focus:outline-none focus:ring-blue-500 focus:border-blue-500 sm:text-sm"
                    value={formData.last_name}
                    onChange={handleChange}
                  />
                </div>
              </div>

              {success && (
                <div className="rounded-md bg-green-50 p-4">
                  <p className="text-sm text-green-800">
                    Profil bilgileriniz başarıyla güncellendi!
                  </p>
                </div>
              )}

              {error && (
                <div className="rounded-md bg-red-50 p-4">
                  <p className="text-sm text-red-800">{error}</p>
                </div>
              )}

              <div>
                <button
                  type="submit"
                  disabled={updating}
                  className="w-full flex justify-center py-2 px-4 border border-transparent rounded-md shadow-sm text-sm font-medium text-white bg-blue-600 hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500 disabled:opacity-50 disabled:cursor-not-allowed"
                >
                  {updating ? "Güncelleniyor..." : "Profili Güncelle"}
                </button>
              </div>
            </form>
          </div>

          {/* Logout Button */}
          <div className="px-4 py-5 sm:p-6 border-t border-gray-200">
            <button
              onClick={handleLogout}
              className="w-full flex justify-center py-2 px-4 border border-transparent rounded-md shadow-sm text-sm font-medium text-white bg-red-600 hover:bg-red-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-red-500"
            >
              Çıkış Yap
            </button>
          </div>
        </div>
      </div>
    </div>
  );
}