using Microsoft.AspNetCore.Components.Authorization;
using System.Security.Claims;
using System.IdentityModel.Tokens.Jwt;

namespace FinControl.Web.Services;

public class AuthStateProvider : AuthenticationStateProvider
{
    private readonly FinControlApiService _apiService;
    private readonly ILocalStorageService _localStorage;

    public AuthStateProvider(FinControlApiService apiService, ILocalStorageService localStorage)
    {
        _apiService = apiService;
        _localStorage = localStorage;
    }

    public override async Task<AuthenticationState> GetAuthenticationStateAsync()
    {
        var token = await _localStorage.GetItemAsync("token");

        if (string.IsNullOrEmpty(token))
        {
            return new AuthenticationState(new ClaimsPrincipal(new ClaimsIdentity()));
        }

        try
        {
            var handler = new JwtSecurityTokenHandler();
            var jwtToken = handler.ReadJwtToken(token);

            // Verificar se o token expirou
            if (jwtToken.ValidTo < DateTime.UtcNow)
            {
                await _localStorage.RemoveItemAsync("token");
                return new AuthenticationState(new ClaimsPrincipal(new ClaimsIdentity()));
            }

            var identity = new ClaimsIdentity(jwtToken.Claims, "jwt");
            var user = new ClaimsPrincipal(identity);

            return new AuthenticationState(user);
        }
        catch
        {
            await _localStorage.RemoveItemAsync("token");
            return new AuthenticationState(new ClaimsPrincipal(new ClaimsIdentity()));
        }
    }

    public async Task Login(string email, string password)
    {
        var response = await _apiService.LoginAsync(email, password);
        if (response != null && !string.IsNullOrEmpty(response.Token))
        {
            await _localStorage.SetItemAsync("token", response.Token);
            await _localStorage.SetItemAsync("userId", response.User.Id.ToString());

            NotifyAuthenticationStateChanged(GetAuthenticationStateAsync());
        }
    }

    public async Task Register(string name, string email, string password)
    {
        var response = await _apiService.RegisterAsync(name, email, password);
        if (response != null && !string.IsNullOrEmpty(response.Token))
        {
            await _localStorage.SetItemAsync("token", response.Token);
            await _localStorage.SetItemAsync("userId", response.User.Id.ToString());

            NotifyAuthenticationStateChanged(GetAuthenticationStateAsync());
        }
    }

    public async Task Logout()
    {
        await _localStorage.RemoveItemAsync("token");
        await _localStorage.RemoveItemAsync("userId");

        NotifyAuthenticationStateChanged(GetAuthenticationStateAsync());
    }

    public async Task<string?> GetToken()
    {
        return await _localStorage.GetItemAsync("token");
    }

    public async Task<string?> GetUserId()
    {
        return await _localStorage.GetItemAsync("userId");
    }
}

public interface ILocalStorageService
{
    Task SetItemAsync(string key, string value);
    Task<string?> GetItemAsync(string key);
    Task RemoveItemAsync(string key);
}

public class LocalStorageService : ILocalStorageService
{
    public async Task SetItemAsync(string key, string value)
    {
        await Task.Run(() =>
        {
            // Simular localStorage - em produção usar Blazored.LocalStorage
            var dict = GetStorage();
            dict[key] = value;
        });
    }

    public async Task<string?> GetItemAsync(string key)
    {
        return await Task.Run(() =>
        {
            var dict = GetStorage();
            return dict.ContainsKey(key) ? dict[key] : null;
        });
    }

    public async Task RemoveItemAsync(string key)
    {
        await Task.Run(() =>
        {
            var dict = GetStorage();
            dict.Remove(key);
        });
    }

    private static Dictionary<string, string> GetStorage()
    {
        // Nota: Esta é uma implementação simples para demo
        // Em produção, usar: https://github.com/Blazored/LocalStorage
        if (!AppData.Storage.ContainsKey("localStorage"))
        {
            AppData.Storage["localStorage"] = new Dictionary<string, string>();
        }
        return (Dictionary<string, string>)AppData.Storage["localStorage"];
    }
}

// Storage em memória (apenas para demo - será perdido ao recarregar)
public static class AppData
{
    public static Dictionary<string, object> Storage { get; } = new();
}

public class LoginResponse
{
    public string? Token { get; set; }
    public UserInfo? User { get; set; }
}

public class UserInfo
{
    public Guid Id { get; set; }
    public string? Name { get; set; }
    public string? Email { get; set; }
}