namespace OpenIdProviderMvc.Controllers {
	using System;
	using System.Collections.Generic;
	using System.Diagnostics.CodeAnalysis;
	using System.Globalization;
	using System.Linq;
	using System.Security.Principal;
	using System.Web;
	using System.Web.Mvc;
	using System.Web.Security;
	using System.Web.UI;
	using OpenIdProviderMvc.Code;

	[HandleError]
	public class AccountController : Controller {
		/// <summary>
		/// Initializes a new instance of the <see cref="AccountController"/> class.
		/// </summary>
		/// <remarks>
		/// This constructor is used by the MVC framework to instantiate the controller using
		/// the default forms authentication and membership providers.
		/// </remarks>
		public AccountController()
			: this(null, null) {
		}

		/// <summary>
		/// Initializes a new instance of the <see cref="AccountController"/> class.
		/// </summary>
		/// <param name="formsAuth">The forms authentication service.</param>
		/// <param name="service">The membership service.</param>
		/// <remarks>
		/// This constructor is not used by the MVC framework but is instead provided for ease
		/// of unit testing this type. See the comments at the end of this file for more
		/// information.
		/// </remarks>
		public AccountController(IFormsAuthentication formsAuth, IMembershipService service) {
			this.FormsAuth = formsAuth ?? new FormsAuthenticationService();
			this.MembershipService = service ?? new AccountMembershipService();
		}

		public IFormsAuthentication FormsAuth { get; private set; }

		public IMembershipService MembershipService { get; private set; }

		public ActionResult LogOn() {
			return View();
		}

		[AcceptVerbs(HttpVerbs.Post)]
		[SuppressMessage("Microsoft.Design", "CA1054:UriParametersShouldNotBeStrings", Justification = "Needs to take same parameter type as Controller.Redirect()")]
		public ActionResult LogOn(string userName, string password, bool rememberMe, string returnUrl) {
			if (!this.ValidateLogOn(userName, password)) {
				return View();
			}

			this.FormsAuth.SignIn(userName, rememberMe);
			if (!string.IsNullOrEmpty(returnUrl)) {
				return Redirect(returnUrl);
			} else {
				return RedirectToAction("Index", "Home");
			}
		}

		public ActionResult LogOff() {
			this.FormsAuth.SignOut();

			return RedirectToAction("Index", "Home");
		}

		public ActionResult Register() {
			ViewData["PasswordLength"] = this.MembershipService.MinPasswordLength;

			return View();
		}

		[AcceptVerbs(HttpVerbs.Post)]
		public ActionResult Register(string userName, string email, string password, string confirmPassword) {
			this.ViewData["PasswordLength"] = this.MembershipService.MinPasswordLength;

			if (this.ValidateRegistration(userName, email, password, confirmPassword)) {
				// Attempt to register the user
				MembershipCreateStatus createStatus = this.MembershipService.CreateUser(userName, password, email);

				if (createStatus == MembershipCreateStatus.Success) {
					this.FormsAuth.SignIn(userName, false /* createPersistentCookie */);
					return RedirectToAction("Index", "Home");
				} else {
					ModelState.AddModelError("_FORM", ErrorCodeToString(createStatus));
				}
			}

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

		[Authorize]
		public ActionResult ChangePassword() {
			ViewData["PasswordLength"] = this.MembershipService.MinPasswordLength;

			return View();
		}

		[Authorize]
		[AcceptVerbs(HttpVerbs.Post)]
		[SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes", Justification = "Exceptions result in password not being changed.")]
		public ActionResult ChangePassword(string currentPassword, string newPassword, string confirmPassword) {
			ViewData["PasswordLength"] = this.MembershipService.MinPasswordLength;

			if (!this.ValidateChangePassword(currentPassword, newPassword, confirmPassword)) {
				return View();
			}

			try {
				if (this.MembershipService.ChangePassword(User.Identity.Name, currentPassword, newPassword)) {
					return RedirectToAction("ChangePasswordSuccess");
				} else {
					ModelState.AddModelError("_FORM", "The current password is incorrect or the new password is invalid.");
					return View();
				}
			} catch {
				ModelState.AddModelError("_FORM", "The current password is incorrect or the new password is invalid.");
				return View();
			}
		}

		public ActionResult ChangePasswordSuccess() {
			return View();
		}

		protected override void OnActionExecuting(ActionExecutingContext filterContext) {
			if (filterContext.HttpContext.User.Identity is WindowsIdentity) {
				throw new InvalidOperationException("Windows authentication is not supported.");
			}
		}

		#region Validation Methods

		private static string ErrorCodeToString(MembershipCreateStatus createStatus) {
			// See http://msdn.microsoft.com/en-us/library/system.web.security.membershipcreatestatus.aspx for
			// a full list of status codes.
			switch (createStatus) {
				case MembershipCreateStatus.DuplicateUserName:
					return "Username already exists. Please enter a different user name.";

				case MembershipCreateStatus.DuplicateEmail:
					return "A username for that e-mail address already exists. Please enter a different e-mail address.";

				case MembershipCreateStatus.InvalidPassword:
					return "The password provided is invalid. Please enter a valid password value.";

				case MembershipCreateStatus.InvalidEmail:
					return "The e-mail address provided is invalid. Please check the value and try again.";

				case MembershipCreateStatus.InvalidAnswer:
					return "The password retrieval answer provided is invalid. Please check the value and try again.";

				case MembershipCreateStatus.InvalidQuestion:
					return "The password retrieval question provided is invalid. Please check the value and try again.";

				case MembershipCreateStatus.InvalidUserName:
					return "The user name provided is invalid. Please check the value and try again.";

				case MembershipCreateStatus.ProviderError:
					return "The authentication provider returned an error. Please verify your entry and try again. If the problem persists, please contact your system administrator.";

				case MembershipCreateStatus.UserRejected:
					return "The user creation request has been canceled. Please verify your entry and try again. If the problem persists, please contact your system administrator.";

				default:
					return "An unknown error occurred. Please verify your entry and try again. If the problem persists, please contact your system administrator.";
			}
		}

		private bool ValidateChangePassword(string currentPassword, string newPassword, string confirmPassword) {
			if (string.IsNullOrEmpty(currentPassword)) {
				ModelState.AddModelError("currentPassword", "You must specify a current password.");
			}
			if (newPassword == null || newPassword.Length < this.MembershipService.MinPasswordLength) {
				ModelState.AddModelError(
					"newPassword",
					string.Format(CultureInfo.CurrentCulture, "You must specify a new password of {0} or more characters.", this.MembershipService.MinPasswordLength));
			}

			if (!string.Equals(newPassword, confirmPassword, StringComparison.Ordinal)) {
				ModelState.AddModelError("_FORM", "The new password and confirmation password do not match.");
			}

			return ModelState.IsValid;
		}

		private bool ValidateLogOn(string userName, string password) {
			if (string.IsNullOrEmpty(userName)) {
				ModelState.AddModelError("username", "You must specify a username.");
			}
			if (string.IsNullOrEmpty(password)) {
				ModelState.AddModelError("password", "You must specify a password.");
			}
			if (!this.MembershipService.ValidateUser(userName, password)) {
				ModelState.AddModelError("_FORM", "The username or password provided is incorrect.");
			}

			return ModelState.IsValid;
		}

		private bool ValidateRegistration(string userName, string email, string password, string confirmPassword) {
			if (string.IsNullOrEmpty(userName)) {
				ModelState.AddModelError("username", "You must specify a username.");
			}
			if (string.IsNullOrEmpty(email)) {
				ModelState.AddModelError("email", "You must specify an email address.");
			}
			if (password == null || password.Length < this.MembershipService.MinPasswordLength) {
				ModelState.AddModelError(
					"password",
					string.Format(CultureInfo.CurrentCulture, "You must specify a password of {0} or more characters.", this.MembershipService.MinPasswordLength));
			}
			if (!string.Equals(password, confirmPassword, StringComparison.Ordinal)) {
				ModelState.AddModelError("_FORM", "The new password and confirmation password do not match.");
			}
			return ModelState.IsValid;
		}

		#endregion
	}
}