import { useEffect, useState } from "react";
import { useNavigate, useParams } from "react-router-dom";
import axiosInstance from "../api/axiosInstance";
import ArtistView from "../components/userProfile/ArtistView";
import ListenerView from "../components/userProfile/ListenerView";
import UserListModal from "../components/userProfile/UserListModal";
import { handleError } from "../utils/error";
import type {
  MusicalEntity,
  Playlist,
  ArtistContribution,
  BaseNonAdminUser,
} from "../utils/types";

interface FollowStatus {
  isFollowing: boolean;
  followerCount: number;
  followingCount: number;
}

interface Artist extends BaseNonAdminUser {
  userType: "ARTIST";
  contributions: ArtistContribution[];
}
interface Listener extends BaseNonAdminUser {
  userType: "LISTENER";
  likedEntities: MusicalEntity[];
  createdPlaylists: Playlist[];
  savedPlaylists: Playlist[];
}

type UserProfile = Artist | Listener;

const UserDetail = () => {
  // user refers to the selected user NOT to the user from context
  const baseURL = import.meta.env.VITE_API_BASE_URL;
  const { username } = useParams();
  const navigate = useNavigate();
  const [user, setUser] = useState<UserProfile | null>(null);
  const [error, setError] = useState<string | null>(null);
  const [showModal, setShowModal] = useState(false);
  const [modalTitle, setModalTitle] = useState("");
  const [modalUsers, setModalUsers] = useState<any[]>([]);
  const [isLoadingModal, setIsLoadingModal] = useState(false);
  const [isFollowing, setIsFollowing] = useState(false);

  const handleFollow = async () => {
    if (!user) return;

    setIsFollowing(true);
    try {
      const response = await axiosInstance.post<FollowStatus>(
        `/users/${username}/follow`,
      );
      setUser((prev) => {
        if (!prev) return null;
        return {
          ...prev,
          isFollowedByCurrentUser: response.data.isFollowing,
          followers: response.data.followerCount,
          following: response.data.followingCount,
        };
      });
    } catch (err: any) {
      setError(handleError(err));
    } finally {
      setIsFollowing(false);
    }
  };

  const handleFollowInModal = async (targetUsername: string) => {
    try {
      const response = await axiosInstance.post<FollowStatus>(
        `/users/${username}/follow`,
      );

      setModalUsers((prevUsers) =>
        prevUsers.map((u) =>
          u.username === targetUsername
            ? { ...u, isFollowedByCurrentUser: response.data.isFollowing }
            : u,
        ),
      );

      // if (user && user.id === targetId) {
      //   setUser((prev) => {
      //     if (!prev) return null;
      //     return {
      //       ...prev,
      //       isFollowedByCurrentUser: response.data.isFollowing,
      //       followers: response.data.followerCount,
      //     };
      //   });
      // }
    } catch (err: any) {
      setError(handleError(err));
    }
  };

  const displayFollowers = async () => {
    setIsLoadingModal(true);
    try {
      const response = await axiosInstance.get(`/users/${username}/followers`);
      setModalUsers(response.data);
      setModalTitle("Followers");
      setShowModal(true);
    } catch (err) {
      setError(handleError(err));
    } finally {
      setIsLoadingModal(false);
    }
  };
  const displayFollowing = async () => {
    setIsLoadingModal(true);
    try {
      const response = await axiosInstance.get(`/users/${username}/following`);
      setModalUsers(response.data);
      setModalTitle("Following");
      setShowModal(true);
    } catch (err: any) {
      setError(handleError(err));
    } finally {
      setIsLoadingModal(false);
    }
  };

  useEffect(() => {
    const fetchUser = async () => {
      setError(null);
      try {
        const response = await axiosInstance.get(`/users/${username}`);
        console.log(response.data);
        setUser(response.data);
      } catch (err: any) {
        setError(handleError(err));
      }
    };
    fetchUser();
  }, [username]);

  if (error) {
    return (
      <div className="p-6 bg-red-50 border border-red-200 text-red-700 rounded-lg">
        <h2 className="font-bold">Error</h2>
        <p>{error}</p>
      </div>
    );
  }

  if (!user) return <div className="p-6">Loading...</div>;

  return (
    <div className="container mx-auto p-6">
      {isLoadingModal && (
        <div className="fixed inset-0 z-40 bg-black/30 backdrop-blur-sm flex items-center justify-center">
          <div className="flex items-center gap-3">
            <div className="w-6 h-6 border-3 border-blue-500 border-t-transparent rounded-full animate-spin"></div>
          </div>
        </div>
      )}
      <button
        onClick={() => navigate(-1)}
        className="mb-4 px-4 py-2 bg-blue-500 text-white rounded hover:bg-blue-600 transition-colors duration-200 cursor-pointer"
      >
        ← Back
      </button>

      <div className="bg-white shadow-lg rounded-lg p-8">
        <div className="flex items-start gap-6 mb-8">
          <div className="shrink-0">
            <div className="w-32 h-32 rounded-full bg-linear-to-br from-blue-400 to-purple-500 flex items-center justify-center text-white text-4xl font-bold shadow-lg overflow-hidden">
              {user.profilePhoto ? (
                <img
                  src={`${baseURL}/${user.profilePhoto}`}
                  alt={user.fullName}
                  className="w-full h-full object-cover"
                />
              ) : (
                user.fullName.charAt(0).toUpperCase()
              )}
            </div>
          </div>

          <div className="flex-1">
            <h1 className="text-4xl font-bold mb-2">{user.fullName}</h1>
            <span className="inline-block px-3 py-1 bg-blue-100 text-blue-800 rounded-full text-sm font-medium mb-4">
              {user.userType}
            </span>

            <div className="flex gap-6 mb-4 text-gray-700">
              <div
                className={`flex flex-col ${user.userType == "LISTENER" ? "cursor-pointer" : "cursor-default"}`}
                onClick={
                  user.userType === "LISTENER" ? displayFollowers : undefined
                }
              >
                <span className="text-2xl font-bold">{user.followers}</span>
                <span className="text-sm text-gray-500">Followers</span>
              </div>
              <div
                className={`flex flex-col ${user.userType == "LISTENER" ? "cursor-pointer" : "cursor-default"}`}
                onClick={
                  user.userType === "LISTENER" ? displayFollowing : undefined
                }
              >
                <span className="text-2xl font-bold">{user.following}</span>
                <span className="text-sm text-gray-500">Following</span>
              </div>
            </div>

            <button
              onClick={handleFollow}
              disabled={isFollowing}
              className={`
                px-6 py-2 font-semibold rounded-lg shadow-md 
                transition-colors duration-200
                ${
                  isFollowing
                    ? "bg-gray-400 text-gray-200 cursor-not-allowed"
                    : user.isFollowedByCurrentUser
                      ? "bg-gray-200 text-gray-700 hover:bg-gray-300 cursor-pointer"
                      : "bg-blue-500 text-white hover:bg-blue-600 cursor-pointer"
                }
              `}
            >
              {user.isFollowedByCurrentUser ? "Unfollow" : "Follow"}
            </button>
          </div>
        </div>

        {user.userType === "ARTIST" ? (
          <ArtistView contributions={user.contributions} />
        ) : (
          <ListenerView
            likedEntities={user.likedEntities}
            createdPlaylists={user.createdPlaylists}
            savedPlaylists={user.savedPlaylists}
          />
        )}

        {showModal && (
          <UserListModal
            title={modalTitle}
            users={modalUsers}
            onClose={() => setShowModal(false)}
            onFollowToggle={handleFollowInModal}
          />
        )}
      </div>
    </div>
  );
};

export default UserDetail;