using Microsoft.IdentityModel.Tokens;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;
namespace Demo
{
    /// <summary>
    /// Token處理類
    /// </summary>
    public class Token
    {
        /// <summary>
        /// 生成JWT
        /// </summary>
        /// <param name="user"></param>
        /// <param name="secretKey"></param>
        /// <param name="issuer"></param>
        /// <param name="audience"></param>
        /// <param name="expiryMinutes"></param>
        /// <returns></returns>
        public static string GenerateJwt(User user, string secretKey, string issuer, string audience, int expiryMinutes)
        {
            var securityKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(secretKey));
            var credentials = new SigningCredentials(securityKey, SecurityAlgorithms.HmacSha256);
            var claims = new[]
            {
                new Claim(ClaimTypes.Name, user.Username),
                new Claim(ClaimTypes.Role, user.Group.ToString()),
            };
            var token = new JwtSecurityToken(
                issuer: issuer,
                audience: audience,
                claims: claims,
                expires: DateTime.UtcNow.AddMinutes(expiryMinutes),
                signingCredentials: credentials
            );
            var tokenHandler = new JwtSecurityTokenHandler();
            var jwtToken = tokenHandler.WriteToken(token);
            return jwtToken;
        }
    }
}