using Domain.Identity;
using Infrastructure;
using Microsoft.Extensions.Configuration;
using Microsoft.IdentityModel.Tokens;
using Models.Identity;
using System;
using System.Collections.Generic;
using System.IdentityModel.Tokens.Jwt;
using System.Linq;
using System.Security.Claims;
using System.Text;

namespace Services.Identity
{
    public class TokenIssuer : ITokenIssuer
    {
        private readonly IConfiguration _configuration;

        public TokenIssuer(IConfiguration configuration)
        {
            _configuration = configuration;
        }

        public JwtSecurityToken Issue(Account user)
        {
            var secret = _configuration.GetSection("Jwt").GetSection("Key").Value;
            var issuer = _configuration.GetSection("Jwt").GetSection("Issuer").Value;
            var claims = GetTokenClaims(user);

            return new JwtSecurityToken(
                issuer: issuer,
                audience: issuer,
                claims: claims,
                expires: DateTime.Now.AddDays(30),
                signingCredentials: new SigningCredentials(new SymmetricSecurityKey(Encoding.ASCII.GetBytes(secret)), SecurityAlgorithms.HmacSha256)
            );
        }

        public PlainToken IssuePlainToken(Account user)
        {
            var token = Issue(user);
            return new PlainToken
            {
                AccessToken = new JwtSecurityTokenHandler().WriteToken(token),
                ExpirationDate = token.ValidTo.ConvertToTimestamp()
            };
        }

        private static IEnumerable<Claim> GetTokenClaims(Account user)
        {
            yield return new Claim(JwtRegisteredClaimNames.Jti, Guid.NewGuid().ToString());
            yield return new Claim(ClaimTypes.Name, user.Username);
            yield return new Claim(ClaimTypes.NameIdentifier, "" + user.Id);
            if(user.AccountRoles != null)   
                foreach (var role in user.AccountRoles)
                {
                    yield return new Claim(ClaimTypes.Role, role.Role.Name);
                }
            yield return new Claim(ITokenIssuer.Claims.Name, user.Name ?? "");            
            yield return new Claim(ITokenIssuer.Claims.Id, "" + user.Id);
            yield return new Claim(ITokenIssuer.Claims.Username, user.Username ?? "");
        }
    }
    public interface ITokenIssuer
    {

        public static class Claims
        {
            public static readonly string Id = "Id";
            public static readonly string Username = "Username";
            public static readonly string Name = "Name";
        }

        JwtSecurityToken Issue(Account user);
        PlainToken IssuePlainToken(Account user);
    }
}