using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;
using Application.Services.Jwt;
using Microsoft.Extensions.Configuration;
using Microsoft.IdentityModel.Tokens;

namespace Infrastructure.Services.Authentication;

public class JwtService(IConfiguration configuration) : IJwtService
{
    private readonly string? _audience = configuration["Jwt:Audience"];
    private readonly double _expiryMinutes = double.Parse(configuration["Jwt:ExpirationTime"]);
    private readonly string? _issuer = configuration["Jwt:Issuer"];
    private readonly string? _secretKey = configuration["Jwt:SecretKey"];

    public string GenerateJwtToken(Guid userId, string roleName, string userName)
    {
        var tokenHandler = new JwtSecurityTokenHandler();
        var key = Encoding.ASCII.GetBytes(_secretKey);
        var tokenDescriptor = new SecurityTokenDescriptor
        {
            Subject = new ClaimsIdentity(new[]
            {
                new Claim(ClaimTypes.NameIdentifier, userId.ToString()), // User ID as GUID
                new Claim(ClaimTypes.Role, roleName), // User role as a readable string
                new Claim(ClaimTypes.Name, userName) // User's name
            }),
            Expires = DateTime.UtcNow.AddMinutes(_expiryMinutes),
            Issuer = _issuer,
            Audience = _audience,
            SigningCredentials =
                new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256Signature)
        };

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


    public bool ValidateJwtToken(string token)
    {
        if (string.IsNullOrWhiteSpace(token))
            return false;

        var tokenHandler = new JwtSecurityTokenHandler();
        var key = Encoding.ASCII.GetBytes(_secretKey);
        try
        {
            tokenHandler.ValidateToken(token, new TokenValidationParameters
            {
                ValidateIssuerSigningKey = true,
                IssuerSigningKey = new SymmetricSecurityKey(key),
                ValidateIssuer = true,
                ValidateAudience = true,
                ValidIssuer = _issuer,
                ValidAudience = _audience,
                ClockSkew = TimeSpan.Zero
            }, out var validatedToken);

            return true;
        }
        catch
        {
            return false;
        }
    }

    public string RefreshToken(string token)
    {
        var principal = ValidateTokenAndGetPrincipal(token);
        if (principal == null) throw new SecurityTokenException("Invalid token.");

        var idClaim = principal.Claims.FirstOrDefault(c => c.Type == ClaimTypes.NameIdentifier);
        if (idClaim == null || !Guid.TryParse(idClaim.Value, out var id))
            throw new SecurityTokenException("Token does not contain a valid ID claim.");

        var roleClaim = principal.Claims.FirstOrDefault(c => c.Type == ClaimTypes.Role);
        var role = roleClaim != null ? roleClaim.Value : "Anonymous";

        var nameClaim = principal.Claims.FirstOrDefault(c => c.Type == ClaimTypes.Name);
        var name = nameClaim != null ? nameClaim.Value : "Unknown";

        return GenerateJwtToken(id, role, name);
    }


    private ClaimsPrincipal ValidateTokenAndGetPrincipal(string token)
    {
        var tokenHandler = new JwtSecurityTokenHandler();
        var key = Encoding.ASCII.GetBytes(_secretKey);
        try
        {
            var principal = tokenHandler.ValidateToken(token, new TokenValidationParameters
            {
                ValidateIssuerSigningKey = true,
                IssuerSigningKey = new SymmetricSecurityKey(key),
                ValidateIssuer = true,
                ValidateAudience = true,
                ValidIssuer = _issuer,
                ValidAudience = _audience,
                ClockSkew = TimeSpan.Zero
            }, out _);

            return principal;
        }
        catch
        {
            // Log or handle validation errors if necessary
            return null;
        }
    }
}