using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.IdentityModel.Tokens;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;

namespace CityInfo.API.Controllers
{
    [Route("api/authentication")]
    [ApiController]
    public class AuthenticationController : ControllerBase
    {
        private readonly IConfiguration _configuration;

        public class AuthenticationRequestBody
        {
            public string? UserName { get; set; }
            public string? Password { get; set; }

        }
        internal class CityInfoUser
        {
            public int UserId { get; set; }
            public string UserName { get; set; }
            public string FirstName { get; set; }
            public string LastName { get; set; }
            public string City { get; set; }
            public CityInfoUser(
                int userId, string userName, string firstName, string lastName, string city)
            {
                UserId = userId;
                UserName = userName;
                FirstName = firstName;
                LastName = lastName;
                City = city;
            }
        }

        public AuthenticationController(IConfiguration configuration)
        {
            _configuration = configuration ?? throw new ArgumentNullException(nameof(configuration));
        }

        [HttpPost("authenticate")]
        public ActionResult<string> Authenticate(AuthenticationRequestBody authenticationRequestBody)
        {
            var user = ValidateUserCredentials(authenticationRequestBody.UserName, authenticationRequestBody.Password);
            if (user == null)
            {
                return Unauthorized();
            }

            var securityKey = new SymmetricSecurityKey(Convert.FromBase64String(_configuration["Authentication:SecretForKey"]));
            var signingCredentials = new SigningCredentials(securityKey, SecurityAlgorithms.HmacSha256);

            var claimsForToken = new List<Claim>
            {
                new Claim("sub", user.UserId.ToString()),
                new Claim("given_name", user.FirstName),
                new Claim("family_name", user.LastName),
                new Claim("city", user.City)
            };

            var jwtSecurityToken = new JwtSecurityToken(
                _configuration["Authentication:Issuer"],
                _configuration["Authentication:Audience"],
                claimsForToken,
                DateTime.UtcNow,
                DateTime.UtcNow.AddHours(1),
                signingCredentials);

            var tokenToReturn = new JwtSecurityTokenHandler().WriteToken(jwtSecurityToken);

            return Ok(tokenToReturn);
        }

        private CityInfoUser ValidateUserCredentials(string? userName, string? password)
        {
            return new CityInfoUser(
                1,
                userName ?? "",
                "Nathan",
                "Pire",
                "Charleroi");
        }
    }

}