using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;
using Azaion.Common.Configs;
using Azaion.Common.Entities;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Options;
using Microsoft.IdentityModel.Tokens;

namespace Azaion.Services;

public interface IAuthService
{
    User? CurrentUser { get; }
    string CreateToken(User user);
}

public class AuthService(IHttpContextAccessor httpContextAccessor, IOptions<JwtConfig> jwtConfig) : IAuthService
{
    public User? CurrentUser
    {
        get
        {
            var claims = httpContextAccessor.HttpContext?.User.Claims.ToDictionary(x => x.Type);
            if (claims == null)
                return null;

            if (!Enum.TryParse(claims[ClaimTypes.Role].Value, out RoleEnum role))
                throw new ApplicationException("Invalid role");

            return new User
            {
                Id = Guid.Parse(claims[ClaimTypes.NameIdentifier].Value),
                Email = claims[ClaimTypes.Name].Value,
                Role = role,
                HardwareHash = claims[Constants.HARDWARE_ID].Value,
            };
        }
    }

    public string CreateToken(User user)
    {
        var signingKey = new SymmetricSecurityKey(Encoding.ASCII.GetBytes(jwtConfig.Value.Secret));

        var tokenHandler = new JwtSecurityTokenHandler();
        var tokenDescriptor = new SecurityTokenDescriptor
        {
            Subject = new ClaimsIdentity([
                new Claim(ClaimTypes.NameIdentifier, user.Id.ToString()),
                new Claim(ClaimTypes.Name, user.Email),
                new Claim(ClaimTypes.Role, user.Role.ToString()),
                new Claim(Constants.HARDWARE_ID, user.HardwareHash ?? "")
            ]),
            Expires = DateTime.UtcNow.AddHours(jwtConfig.Value.TokenLifetimeHours),
            Issuer = jwtConfig.Value.Issuer,
            Audience = jwtConfig.Value.Audience,
            SigningCredentials = new SigningCredentials(signingKey, SecurityAlgorithms.HmacSha256Signature)
        };

        var token = tokenHandler.CreateToken(tokenDescriptor);
        return tokenHandler.WriteToken(token);
    }
}