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

namespace OrdersManagement;

public class CustomAuthenticationStateProvider(ILocalStorageService localStorage) : AuthenticationStateProvider
{
    private string? _token;
    private ClaimsPrincipal _currentUser = new(new ClaimsIdentity());

    public override async Task<AuthenticationState> GetAuthenticationStateAsync()
    {
        _token = await localStorage.GetItemAsync<string>("authToken");
        
        if (string.IsNullOrEmpty(_token))
        {
            return await Task.FromResult(new AuthenticationState(new ClaimsPrincipal(new ClaimsIdentity())));
        }

        var handler = new JwtSecurityTokenHandler();
        var jwtToken = handler.ReadJwtToken(_token);
        var identity = new ClaimsIdentity(jwtToken.Claims, "jwt", JwtRegisteredClaimNames.Sub, null);
        _currentUser = new ClaimsPrincipal(identity);
        return await Task.FromResult(new AuthenticationState(_currentUser));
    }

    public async Task MarkUserAsAuthenticated(string? token)
    {
        _token = token;
        await localStorage.SetItemAsync("authToken", token);
        var handler = new JwtSecurityTokenHandler();
        var jwtToken = handler.ReadJwtToken(token);
        var identity = new ClaimsIdentity(jwtToken.Claims, "jwt", JwtRegisteredClaimNames.Sub, null);
        _currentUser = new ClaimsPrincipal(identity);
        NotifyAuthenticationStateChanged(Task.FromResult(new AuthenticationState(_currentUser)));
    }

    public async Task MarkUserAsLoggedOut()
    {
        _token = null;
        await localStorage.RemoveItemAsync("authToken");
        _currentUser = new ClaimsPrincipal(new ClaimsIdentity());
        NotifyAuthenticationStateChanged(Task.FromResult(new AuthenticationState(_currentUser)));
    }
    
    public string? GetToken() => _token;
    public ClaimsPrincipal GetCurrentUser() => _currentUser;
}