using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Security.Claims;
using System.Threading.Tasks;
using System.Web;
using System.Web.Mvc;
using EnVisage.Code.BLL;
using EnVisage.Properties;
using Microsoft.AspNet.Identity;
using Microsoft.AspNet.Identity.EntityFramework;
using Microsoft.Owin.Security;
using EnVisage.Models;
using EnVisage.Code;
using System.Net;
using System.DirectoryServices;
using System.DirectoryServices.AccountManagement;

namespace EnVisage.Controllers
{
    [Authorize]
    public class AccountController : BaseController
    {
        public AccountController()
            : this(new UserManager<ApplicationUser>(new UserStore<ApplicationUser>(new ApplicationDbContext())))
        {
        }

        public AccountController(UserManager<ApplicationUser> userManager)
        {
            UserManager = userManager;
        }

        public UserManager<ApplicationUser> UserManager { get; private set; }

        //
        // GET: /Account/Login
        [AllowAnonymous]
        public ActionResult Login(string returnUrl)
        {
            ViewBag.ReturnUrl = returnUrl;
            return View();
        }

        //
        // POST: /Account/Login
        [HttpPost]
        [AllowAnonymous]
        [ValidateAntiForgeryToken]
        public async Task<ActionResult> Login(LoginViewModel model, string returnUrl)
        {
            if (ModelState.IsValid)
            {
                var user = await UserManager.FindAsync(model.UserName, model.Password);
                if (user != null)
                {
					if (user.Type == (int)Code.UserType.Active)
					{
						await SignInAsync(user, model.RememberMe);
                        return RedirectToLocal(returnUrl);
					}
                    else
						ModelState.AddModelError("", "Sorry, your account is not active.");
                }
                else
                {
                    //var LDAPLogin="planit\\serverLogin"; //For directory lookup
                    //var LDAPPass = "serverPass";
                    //DirectoryEntry entry = new DirectoryEntry("LDAP://planitserver/OU=People,O=planit", LDAPLogin, LDAPPass);
                    //                    //DirectorySearcher search = new DirectorySearcher(
                    //                    //    entry,
                    //                    //    "(uid=" + "planit\\" +  model.UserName + ")",
                    //                    //    new string[] { "uid" }
                    //                    //);
                    //                    //search.SearchScope = System.DirectoryServices.SearchScope.Subtree;
                    //                    //SearchResult found = search.FindOne();
                    //                    //if (found == null){
                    //                    //    ModelState.AddModelError("", "Invalid username or password.");
                    //                    //    return View(model);
                    //                    //}
                    //bool result;
                    //using(var context = new PrincipalContext(ContextType.Domain, "planit", LDAPLogin, LDAPPass)) {
                    //    //Username and password for authentication.
                    //    result = context.ValidateCredentials("planit\\" + model.UserName, model.Password); 
                    //}
                    //if (result)
                    //{
                    //    var newuser = new ApplicationUser();
                    //    newuser.UserName = model.UserName;
                    //    var creationResult = await UserManager.CreateAsync(user, model.Password);

                    //    if (creationResult.Succeeded)
                    //        creationResult = UserManager.AddToRole(newuser.Id, "User");
                    //    await SignInAsync(newuser, model.RememberMe);
                    //    return RedirectToLocal(returnUrl);
                    //}
                    //else 
                    ModelState.AddModelError("", "Invalid username or password.");
                }
            }

            // If we got this far, something failed, redisplay form
            return View(model);
        }

        //
        // GET: /Account/Register
        [AllowAnonymous]
        [Obsolete]
        public ActionResult Register()
        {
            return View();
        }

        //
        // POST: /Account/Register
        [HttpPost]
        [AllowAnonymous]
        [ValidateAntiForgeryToken]
        [Obsolete]
        public async Task<ActionResult> Register(RegisterViewModel model)
        {
            if (ModelState.IsValid)
            {
                var user = new ApplicationUser() { UserName = model.UserName, PagePreferences = string.Empty};
                var result = await UserManager.CreateAsync(user, model.Password);
                if (result.Succeeded)
                {
                    await SignInAsync(user, isPersistent: false);
                    return RedirectToAction("Index", "Home");
                }
                else
                {
                    AddErrors(result);
                }
            }

            // If we got this far, something failed, redisplay form
            return View(model);
        }

        //
        // POST: /Account/Disassociate
        [HttpPost]
        [ValidateAntiForgeryToken]
        [Obsolete]
        public async Task<ActionResult> Disassociate(string loginProvider, string providerKey)
        {
            ManageMessageId? message = null;
            IdentityResult result = await UserManager.RemoveLoginAsync(User.Identity.GetUserId(), new UserLoginInfo(loginProvider, providerKey));
            if (result.Succeeded)
            {
                message = ManageMessageId.RemoveLoginSuccess;
            }
            else
            {
                message = ManageMessageId.Error;
            }
            return RedirectToAction("Manage", new { Message = message });
        }

        //
        // GET: /Account/Manage
        [Obsolete]
        public ActionResult Manage(ManageMessageId? message)
        {
            ViewBag.StatusMessage =
                message == ManageMessageId.ChangePasswordSuccess ? "Your password has been changed."
                : message == ManageMessageId.SetPasswordSuccess ? "Your password has been set."
                : message == ManageMessageId.RemoveLoginSuccess ? "The external login was removed."
                : message == ManageMessageId.Error ? "An error has occurred."
                : "";
            ViewBag.HasLocalPassword = HasPassword();
            ViewBag.ReturnUrl = Url.Action("Manage");

			var userId = User.Identity.GetUserId();
			var user = DbContext.AspNetUsers.Find(userId);
			var model = new ManageUserViewModel()
			{
				Email = user.Email,
				Phone = user.Phone,
				PreferredResourceAllocation = user.PreferredResourceAllocation,
			};

            return View(model);
        }

        //
        // POST: /Account/Manage
        [HttpPost]
        [ValidateAntiForgeryToken]
        [Obsolete]
        public async Task<ActionResult> Manage(ManageUserViewModel model)
        {
            bool hasPassword = HasPassword();
            ViewBag.HasLocalPassword = hasPassword;
            ViewBag.ReturnUrl = Url.Action("Manage");
            if (hasPassword)
            {
                if (ModelState.IsValid)
                {
                    IdentityResult result = await UserManager.ChangePasswordAsync(User.Identity.GetUserId(), model.OldPassword, model.NewPassword);
                    if (result.Succeeded)
                    {
                        return RedirectToAction("Manage", new { Message = ManageMessageId.ChangePasswordSuccess });
                    }
                    else
                    {
                        AddErrors(result);
                    }
                }
            }
            else
            {
                // User does not have a password so remove any validation errors caused by a missing OldPassword field
                ModelState state = ModelState["OldPassword"];
                if (state != null)
                {
                    state.Errors.Clear();
                }

                if (ModelState.IsValid)
                {
                    IdentityResult result = await UserManager.AddPasswordAsync(User.Identity.GetUserId(), model.NewPassword);
                    if (result.Succeeded)
                    {
                        return RedirectToAction("Manage", new { Message = ManageMessageId.SetPasswordSuccess });
                    }
                    else
                    {
                        AddErrors(result);
                    }
                }
            }

            // If we got this far, something failed, redisplay form
            return View(model);
        }

		//
		// POST: /Account/ChangeEmail
		[HttpPost]
		[Obsolete]
		public JsonResult ChangeEmailAndPhone(string newEmail, string newPhone, bool newPreferredResourceAllocation)
		{
			try
			{
				var userId = User.Identity.GetUserId();
				var user = UserManager.FindById(userId);
				
				if (user.Email != newEmail)
					user.Email = newEmail;
				if (user.Phone != newPhone)
					user.Phone = newPhone;
				user.PreferredResourceAllocation = newPreferredResourceAllocation;

				UserManager.Update(user);
				DbContext.SaveChanges();
			}
			catch (Exception ex)
			{
				return Json(new { Status = "Error", Msg = ex.Message, Exception = ex.ToString() });
			}

			return Json(new { Status = "OK" });
		}

        //
        // POST: /Account/ExternalLogin
        [HttpPost]
        [AllowAnonymous]
        [ValidateAntiForgeryToken]
        [Obsolete]
        public ActionResult ExternalLogin(string provider, string returnUrl)
        {
            // Request a redirect to the external login provider
            return new ChallengeResult(provider, Url.Action("ExternalLoginCallback", "Account", new { ReturnUrl = returnUrl }));
        }

        //
        // GET: /Account/ExternalLoginCallback
        [AllowAnonymous]
        [Obsolete]
        public async Task<ActionResult> ExternalLoginCallback(string returnUrl)
        {
            var loginInfo = await AuthenticationManager.GetExternalLoginInfoAsync();
            if (loginInfo == null)
            {
                return RedirectToAction("Login");
            }

            // Sign in the user with this external login provider if the user already has a login
            var user = await UserManager.FindAsync(loginInfo.Login);
            if (user != null)
            {
                await SignInAsync(user, isPersistent: false);
                return RedirectToLocal(returnUrl);
            }
            else
            {
                // If the user does not have an account, then prompt the user to create an account
                ViewBag.ReturnUrl = returnUrl;
                ViewBag.LoginProvider = loginInfo.Login.LoginProvider;
                return View("ExternalLoginConfirmation", new ExternalLoginConfirmationViewModel { UserName = loginInfo.DefaultUserName });
            }
        }

        //
        // POST: /Account/LinkLogin
        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult LinkLogin(string provider)
        {
            // Request a redirect to the external login provider to link a login for the current user
            return new ChallengeResult(provider, Url.Action("LinkLoginCallback", "Account"), User.Identity.GetUserId());
        }

        //
        // GET: /Account/LinkLoginCallback
        public async Task<ActionResult> LinkLoginCallback()
        {
            var loginInfo = await AuthenticationManager.GetExternalLoginInfoAsync(XsrfKey, User.Identity.GetUserId());
            if (loginInfo == null)
            {
                return RedirectToAction("Manage", new { Message = ManageMessageId.Error });
            }
            var result = await UserManager.AddLoginAsync(User.Identity.GetUserId(), loginInfo.Login);
            if (result.Succeeded)
            {
                return RedirectToAction("Manage");
            }
            return RedirectToAction("Manage", new { Message = ManageMessageId.Error });
        }

        //
        // POST: /Account/ExternalLoginConfirmation
        [HttpPost]
        [AllowAnonymous]
        [ValidateAntiForgeryToken]
        public async Task<ActionResult> ExternalLoginConfirmation(ExternalLoginConfirmationViewModel model, string returnUrl)
        {
            if (User.Identity.IsAuthenticated)
            {
                return RedirectToAction("Manage");
            }

            if (ModelState.IsValid)
            {
                // Get the information about the user from the external login provider
                var info = await AuthenticationManager.GetExternalLoginInfoAsync();
                if (info == null)
                {
                    return View("ExternalLoginFailure");
                }
                var user = new ApplicationUser() { UserName = model.UserName, PagePreferences = string.Empty};
                var result = await UserManager.CreateAsync(user);
                if (result.Succeeded)
                {
                    result = await UserManager.AddLoginAsync(user.Id, info.Login);
                    if (result.Succeeded)
                    {
                        await SignInAsync(user, isPersistent: false);
                        return RedirectToLocal(returnUrl);
                    }
                }
                AddErrors(result);
            }

            ViewBag.ReturnUrl = returnUrl;
            return View(model);
        }

        //
        // POST: /Account/LogOff
        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult LogOff()
        {
            AuthenticationManager.SignOut();
            return RedirectToAction("Index", "Home");
        }

        //
        // GET: /Account/ExternalLoginFailure
        [AllowAnonymous]
        public ActionResult ExternalLoginFailure()
        {
            return View();
        }

        [ChildActionOnly]
        [Obsolete]
        public ActionResult RemoveAccountList()
        {
            var linkedAccounts = UserManager.GetLogins(User.Identity.GetUserId());
            ViewBag.ShowRemoveButton = HasPassword() || linkedAccounts.Count > 1;
            return (ActionResult)PartialView("_RemoveAccountPartial", linkedAccounts);
        }

		//
		// GET: /Account/Activate
		[AllowAnonymous]
		public ActionResult Activate(string userId)
		{
			var user = UserManager.FindById(userId);
			if (user == null)
				return new HttpStatusCodeResult(HttpStatusCode.BadRequest);

			if (user.Type != (int)UserType.Pending)
				ModelState.AddModelError("", "This account is already activated.");

			var activatedUser = new ActivationUserModel()
			{
				Email = user.Email,
				UserName = user.UserName,
				Password = string.Empty,
				ConfirmationPassword = string.Empty,
				UserId = user.Id
			};

			return View(activatedUser);
		}

		//
		// POST: /Accont/Activate
		[AllowAnonymous]
		[HttpPost]
		public async Task<ActionResult> Activate(ActivationUserModel model)
		{
			if (ModelState.IsValid)
			{
				if (!string.IsNullOrWhiteSpace(model.UserId))
				{
					ApplicationDbContext cnt = new ApplicationDbContext();
					var userManager = new UserManager<ApplicationUser>(new UserStore<ApplicationUser>(cnt));
					var user = userManager.FindById(model.UserId);
					if (user == null)
						return new HttpStatusCodeResult(HttpStatusCode.BadRequest);

					if (user.Type != (int)UserType.Pending)
						ModelState.AddModelError("", "This account is already activated.");

					var passwordHash = userManager.PasswordHasher.HashPassword(model.Password);
					user.PasswordHash = passwordHash;
					user.Type = (int)UserType.Active;
					cnt.SaveChanges();

					await SignInAsync(user, false);

					return RedirectToAction("Index", "Home");
				}
				else
					ModelState.AddModelError("", "This user is not exsist.");
			}
				
			return View();
		}

        [AllowAnonymous]
        public ActionResult ForgotPassword()
        {
            return View(new ForgotPasswordModel());
        }

        [HttpPost]
        [ValidateAntiForgeryToken]
        [AllowAnonymous]
        public ActionResult ForgotPassword(ForgotPasswordModel model)
        {
            if (ModelState.IsValid)
            {
                try
                {
                    using (var db = new EnVisageEntities())
                    {
                        var user = db.AspNetUsers.FirstOrDefault(t => t.Email == model.Email);
                        if (user == null)
                        {
                            ModelState.AddModelError("", "No matching email address found");
                            return View(model);
                        }
                        SendResetPasswordLink(user.Id, user.UserName, user.Email, db);
                    }
                    model.Sent = true;
                }
                catch (BLLException blEx) // handle any system specific error
                {
                    // display error message if required
                    if (blEx.DisplayError)
                        ModelState.AddModelError(string.Empty, blEx.Message);
                    else // if display not requried then display modal form with general error message 
                    {
                        LogException(blEx);
                        SetErrorScript();
                    }
                }
                catch (Exception exception) // handle any unexpected error
                {
                    LogException(exception);
                    SetErrorScript();
                }
            }
            return View(model);
        }

        [HttpPost]
        public ActionResult ResetPwd(string id)
        {
            try
            {
                using (var db = new EnVisageEntities())
                {
                    var user = db.AspNetUsers.FirstOrDefault(t => t.Id == id);
                    if (user == null)
                    {
                        throw new ArgumentException("No matching user Id '{0}' found", id);
                    }
                    SendResetPasswordLink(user.Id, user.UserName, user.Email, db);
                }
                return Json(new {status = "OK"});
            }
            catch (Exception exception) // handle any unexpected error
            {
                LogException(exception);
                return Json(new {status = "ERROR"});
            }
        }

        [AllowAnonymous]
        public ActionResult RestorePassword(Guid token)
        {
            if (Guid.Empty.Equals(token))
                return new HttpNotFoundResult();
            var model = new RestorePasswordModel();
            try
            {
                using (var db = new EnVisageEntities())
                {
                    var request = db.PasswordResetRequests.FirstOrDefault(t => t.Token == token);
                    if (request == null)
                        return new HttpNotFoundResult();

                    if (request.ValidUntil < DateTime.Now)
                        throw new RestorePasswordTokenExpiredException();
                }
            }
            catch (BLLException blEx) // handle any system specific error
            {
                // display error message if required
                if (blEx.DisplayError)
                    ModelState.AddModelError(string.Empty, blEx.Message);
                else // if display not requried then display modal form with general error message 
                {
                    LogException(blEx);
                    SetErrorScript();
                }
            }
            catch (Exception exception) // handle any unexpected error
            {
                LogException(exception);
                SetErrorScript();
            }
            return View(model);
        }

        [HttpPost]
        [ValidateAntiForgeryToken]
        [AllowAnonymous]
        public ActionResult RestorePassword(RestorePasswordModel model)
        {
            if (ModelState.IsValid)
            {
                try
                {
                    using (var db = new EnVisageEntities())
                    {
                        var request = db.PasswordResetRequests.FirstOrDefault(t => t.Token == model.Token);
                        if (request == null)
                            return new HttpNotFoundResult();

                        if (request.ValidUntil < DateTime.Now)
                            throw new RestorePasswordTokenExpiredException();
                        var user = db.AspNetUsers.FirstOrDefault(t => t.Id == request.UserId);
                        if (user == null)
                            return new HttpNotFoundResult();

                        db.Entry(request).State = EntityState.Deleted;
                        UserManager.RemovePassword(user.Id);
                        UserManager.AddPassword(user.Id, model.Password);
                        db.SaveChanges();
                    }
                    model.Restored = true;
                }
                catch (BLLException blEx) // handle any system specific error
                {
                    // display error message if required
                    if (blEx.DisplayError)
                        ModelState.AddModelError(string.Empty, blEx.Message);
                    else // if display not requried then display modal form with general error message 
                    {
                        LogException(blEx);
                        SetErrorScript();
                    }
                }
                catch (Exception exception) // handle any unexpected error
                {
                    LogException(exception);
                    SetErrorScript();
                }
            }
            return View(model);
        }

        protected override void Dispose(bool disposing)
        {
            if (disposing && UserManager != null)
            {
                UserManager.Dispose();
                UserManager = null;
            }
            base.Dispose(disposing);
        }

        #region Helpers
        // Used for XSRF protection when adding external logins
        private const string XsrfKey = "XsrfId";

        private IAuthenticationManager AuthenticationManager
        {
            get
            {
                return HttpContext.GetOwinContext().Authentication;
            }
        }

        private async Task SignInAsync(ApplicationUser user, bool isPersistent)
        {
            AuthenticationManager.SignOut(DefaultAuthenticationTypes.ExternalCookie);
            var identity = await UserManager.CreateIdentityAsync(user, DefaultAuthenticationTypes.ApplicationCookie);
            var auth_props = new AuthenticationProperties() { IsPersistent = isPersistent };
            if(isPersistent)
                auth_props.ExpiresUtc = DateTime.UtcNow.AddHours(12);
            AuthenticationManager.SignIn(auth_props, identity);
        }

        private void AddErrors(IdentityResult result)
        {
            foreach (var error in result.Errors)
            {
                ModelState.AddModelError("", error);
            }
        }

        private bool HasPassword()
        {
            var user = UserManager.FindById(User.Identity.GetUserId());
            if (user != null)
            {
                return user.PasswordHash != null;
            }
            return false;
        }

        public enum ManageMessageId
        {
            ChangePasswordSuccess,
            SetPasswordSuccess,
            RemoveLoginSuccess,
            Error
        }

        private ActionResult RedirectToLocal(string returnUrl)
        {
            if (Url.IsLocalUrl(returnUrl))
            {
                return Redirect(returnUrl);
            }
            else
            {
                return RedirectToAction("Index", "Home");
            }
        }

        private class ChallengeResult : HttpUnauthorizedResult
        {
            public ChallengeResult(string provider, string redirectUri) : this(provider, redirectUri, null)
            {
            }

            public ChallengeResult(string provider, string redirectUri, string userId)
            {
                LoginProvider = provider;
                RedirectUri = redirectUri;
                UserId = userId;
            }

            public string LoginProvider { get; set; }
            public string RedirectUri { get; set; }
            public string UserId { get; set; }

            public override void ExecuteResult(ControllerContext context)
            {
                var properties = new AuthenticationProperties() { RedirectUri = RedirectUri };
                if (UserId != null)
                {
                    properties.Dictionary[XsrfKey] = UserId;
                }
                context.HttpContext.GetOwinContext().Authentication.Challenge(properties, LoginProvider);
            }
        }

        private static void SendResetPasswordLink(string userId, string userName, string email, EnVisageEntities db)
        {
            var request = new PasswordResetRequest
            {
                Token = Guid.NewGuid(),
                Id = Guid.NewGuid(),
                UserId = userId,
                ValidUntil = DateTime.Now.AddDays(Settings.Default.ForgotPasswordLinkTTLDays)
            };
            db.PasswordResetRequests.Add(request);

            db.SaveChanges();

            MailManager.SendRestorePasswordMessage(email, request.Token, userName);
        }
        #endregion
    }
}