using GermanApp.Application.DTOs.Auth;
using GermanApp.Domain.Entities;

namespace GermanApp.Application.Interfaces;

/// <summary>
/// Interface for authentication services.
/// Part of the Application layer.
/// </summary>
public interface IAuthService
{
    /// <summary>
    /// Registers a new user.
    /// </summary>
    /// <param name="registerDto">User registration data</param>
    /// <returns>Authentication response with token</returns>
    Task<AuthResponse> RegisterAsync(RegisterDto registerDto);

    /// <summary>
    /// Authenticates a user and returns a JWT token.
    /// </summary>
    /// <param name="loginDto">User login data</param>
    /// <returns>Authentication response with token</returns>
    Task<AuthResponse> LoginAsync(LoginDto loginDto);

    /// <summary>
    /// Gets the current authenticated user.
    /// </summary>
    /// <param name="userId">User ID from token claims</param>
    /// <returns>The user entity</returns>
    Task<User?> GetCurrentUserAsync(int userId);

    /// <summary>
    /// Refreshes the access token using a refresh token.
    /// </summary>
    /// <param name="refreshToken">The refresh token</param>
    /// <returns>New access token and refresh token</returns>
    Task<RefreshTokenResponse> RefreshTokenAsync(string refreshToken);

    /// <summary>
    /// Revokes a refresh token.
    /// </summary>
    /// <param name="refreshToken">The refresh token to revoke</param>
    Task RevokeRefreshTokenAsync(string refreshToken);

    /// <summary>
    /// Creates the first admin user (bootstrap).
    /// This is a special method that creates an admin user without requiring authentication.
    /// </summary>
    /// <param name="registerDto">Admin user registration data</param>
    /// <returns>Authentication response with token</returns>
    Task<AuthResponse> CreateAdminUserAsync(RegisterDto registerDto);

    /// <summary>
    /// Checks if an admin user already exists.
    /// </summary>
    /// <returns>True if admin user exists, false otherwise</returns>
    Task<bool> AdminUserExistsAsync();
}