using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using InstaVibe.Models;


namespace InstaVibe.Controllers
{
    public class PublicProfileController : Controller
    {
        public string connectionString = ConfigurationManager.ConnectionStrings["InstaVibe"].ConnectionString.ToString();

        // ====================== Public Profile Page (Index) ======================
        public ActionResult Index(int id)
        {

            if (Session["UserId"] == null)
            {
                return RedirectToAction("Login", "Account");
            }

            int loggedInUserId = Convert.ToInt32(Session["UserId"]);

            // ✅ Viewed user ka role DB se check karo
            string viewedUserType = GetUserRole(id);
            if (viewedUserType == "Alumni")
                return RedirectToAction("Public", "AlumniProfile", new { id = id });



            SelfProfileModel model = new SelfProfileModel();

            using (SqlConnection con = new SqlConnection(connectionString))
            {
                con.Open();

                // User info jisko profile dekhni hai
                string userQuery = "SELECT profile_picture, department, fullname FROM users WHERE user_id = @UserId";

                using (SqlCommand userCmd = new SqlCommand(userQuery, con))
                {
                    userCmd.Parameters.AddWithValue("@UserId", id);

                    using (SqlDataReader reader = userCmd.ExecuteReader())
                    {
                        if (reader.Read())
                        {
                            model.UserId = id;
                            model.ProfileImage = reader["profile_picture"].ToString();
                            model.Department = reader["department"].ToString();
                            model.FullName = reader["fullname"].ToString();
                        }
                    }
                }

                // Posts of the user being viewed
                model.Posts = new List<PostModel>();

                string postsQuery = @"
            SELECT p.media_url, p.caption, p.created_at, u.username, u.profile_picture
            FROM Posts p
            INNER JOIN users u ON p.user_id = u.user_id
            WHERE p.user_id = @UserId
            ORDER BY p.created_at DESC";

                using (SqlCommand postCmd = new SqlCommand(postsQuery, con))
                {
                    postCmd.Parameters.AddWithValue("@UserId", id);

                    using (SqlDataReader reader = postCmd.ExecuteReader())
                    {
                        while (reader.Read())
                        {
                            PostModel post = new PostModel()
                            {
                                MediaUrl = reader["media_url"].ToString(),
                                Caption = reader["caption"].ToString(),
                                PostDate = Convert.ToDateTime(reader["created_at"]),
                                Username = reader["username"].ToString(),
                                ProfileImage = reader["profile_picture"].ToString()
                            };
                            model.Posts.Add(post);
                        }
                    }
                }

                model.PostsCount = model.Posts.Count;

                // Follower/Following counts
                model.FollowersCount = GetFollowersCount(id, con);
                model.FollowingCount = GetFollowingCount(id, con);

                // Relationship checks
                model.IsFollowing = DatabaseHelper.IsFollowing(loggedInUserId, id);
                model.HasSentRequest = HasSentFriendRequest(loggedInUserId, id, con);


                model.IsCurrentUser = (id == loggedInUserId);
            }

            return View("Index", model);
        }

        private string GetUserRole(int userId)
        {
            using (SqlConnection con = new SqlConnection(connectionString))
            {
                con.Open();
                SqlCommand cmd = new SqlCommand(
                    "SELECT user_type FROM users WHERE user_id = @Id", con); // role → user_type
                cmd.Parameters.AddWithValue("@Id", userId);
                object result = cmd.ExecuteScalar();
                return result?.ToString() ?? "Student";
            }
        }
        private int GetFollowersCount(int userId, SqlConnection con)
        {
            string query = "SELECT COUNT(*) FROM followers WHERE following_user_id = @UserId";
            using (SqlCommand cmd = new SqlCommand(query, con))
            {
                cmd.Parameters.AddWithValue("@UserId", userId);
                return (int)cmd.ExecuteScalar();
            }
        }

        private int GetFollowingCount(int userId, SqlConnection con)
        {
            string query = "SELECT COUNT(*) FROM followers WHERE follower_user_id = @UserId";
            using (SqlCommand cmd = new SqlCommand(query, con))
            {
                cmd.Parameters.AddWithValue("@UserId", userId);
                return (int)cmd.ExecuteScalar();
            }
        }

        private bool HasSentFriendRequest(int fromUserId, int toUserId, SqlConnection con)
        {
            string query = @"
         SELECT COUNT(*) 
         FROM FriendRequests 
         WHERE from_user_id = @FromUserId 
           AND to_user_id = @ToUserId 
           AND status = 'Pending'";

            using (SqlCommand cmd = new SqlCommand(query, con))
            {
                cmd.Parameters.AddWithValue("@FromUserId", fromUserId);
                cmd.Parameters.AddWithValue("@ToUserId", toUserId);
                return (int)cmd.ExecuteScalar() > 0;
            }
        }

        // Followers popup partial
        public ActionResult GetFollowers(int userId)
        {
            var followers = DatabaseHelper.GetFollowers(userId);
            ViewBag.Type = "followers";
            return PartialView("_FollowListPartial", followers);
        }

        // Following popup partial
        public ActionResult GetFollowing(int userId)
        {
            var following = DatabaseHelper.GetFollowing(userId);
            ViewBag.Type = "following";
            return PartialView("_FollowListPartial", following);
        }

        // ====================== Pending Friend Requests ======================
        public JsonResult GetPendingRequests()
        {
            int userId = Convert.ToInt32(Session["UserId"]);
            using (SqlConnection con = new SqlConnection(connectionString))
            {
                con.Open();
                string query = @"
     SELECT fr.request_id, u.username, u.profile_picture
     FROM FriendRequests fr
     INNER JOIN Users u ON u.user_id = fr.from_user_id
     WHERE fr.to_user_id = @UserId AND fr.status = 'Pending'";

                SqlCommand cmd = new SqlCommand(query, con);
                cmd.Parameters.AddWithValue("@UserId", userId);

                SqlDataAdapter da = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                da.Fill(dt);

                var requests = dt.AsEnumerable().Select(row => new
                {
                    RequestId = row["request_id"],
                    Username = row["username"].ToString(),
                    ProfilePic = row["profile_picture"].ToString()
                });

                return Json(requests, JsonRequestBehavior.AllowGet);
            }
        }
    }
}