using System;
using System.ComponentModel.DataAnnotations;
using System.Text;
using System.Text.Encodings.Web;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authorization;

using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Identity.UI.Services;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.AspNetCore.WebUtilities;
using My.ProjectName.Services.EmailService;

namespace My.ProjectName.Areas.Identity.Pages.Account
{
    [AllowAnonymous]
    public class ResendEmailConfirmationModel : PageModel
    {
        private readonly UserManager<IdentityUser> _userManager;
        private readonly Services.EmailService.IEmailSender _emailSender;

        public ResendEmailConfirmationModel(UserManager<IdentityUser> userManager, Services.EmailService.IEmailSender emailSender)
        {
            _userManager = userManager;
            _emailSender = emailSender;
        }

        [BindProperty]
        public InputModel Input { get; set; }

        public class InputModel
        {
            [Required]
            [EmailAddress]
            public string Email { get; set; }
        }

        public void OnGet()
        {
        }

        public async Task<IActionResult> OnPostAsync()
        {
            if (!ModelState.IsValid)
            {
                return Page();
            }

            var user = await _userManager.FindByEmailAsync(Input.Email);
            if (user == null)
            {
                ModelState.AddModelError(string.Empty, "Verification email sent. Please check your email.");
                return Page();
            }

            var userId = await _userManager.GetUserIdAsync(user);
            var code = await _userManager.GenerateEmailConfirmationTokenAsync(user);
            code = WebEncoders.Base64UrlEncode(Encoding.UTF8.GetBytes(code));
            var callbackUrl = Url.Page(
                "/Account/ConfirmEmail",
                pageHandler: null,
                values: new { userId = userId, code = code },
                protocol: Request.Scheme);

            Message message = new Message(
                new string[] { Input.Email },
                "Confirm your email",
                $"Please confirm your account by <a href='{HtmlEncoder.Default.Encode(callbackUrl)}'>clicking here</a>.");
            await _emailSender.SendEmailAsync(message);

            ModelState.AddModelError(string.Empty, "Verification email sent. Please check your email.");
            return Page();
        }
    }
}