using System.Security.Claims;
using Microsoft.AspNetCore.Components.Authorization;
using Microsoft.AspNetCore.Components.Server;
using Microsoft.AspNetCore.Identity;
using Microsoft.Extensions.Options;
using MyApp.Data;

namespace MyApp.Identity;

public class IdentityRevalidatingAuthenticationStateProvider : RevalidatingServerAuthenticationStateProvider
{
    private readonly IServiceScopeFactory _scopeFactory;
    private readonly IdentityOptions _options;

    public IdentityRevalidatingAuthenticationStateProvider(
        ILoggerFactory loggerFactory,
        IServiceScopeFactory scopeFactory, Microsoft.Extensions.Options.IOptions<IdentityOptions> optionsAccessor)
        : base(loggerFactory)
    {
        _scopeFactory = scopeFactory;
        _options = optionsAccessor.Value;
    }

    protected override TimeSpan RevalidationInterval => TimeSpan.FromMinutes(30);

    protected override async Task<bool> ValidateAuthenticationStateAsync(
        AuthenticationState authenticationState, CancellationToken cancellationToken)
    {
        // Get the user manager from a new scope to ensure it fetches fresh data
        await using var scope = _scopeFactory.CreateAsyncScope();
        var userManager = scope.ServiceProvider.GetRequiredService<UserManager<ApplicationUser>>();
        return await ValidateSecurityStampAsync(userManager, authenticationState.User);
    }

    private async Task<bool> ValidateSecurityStampAsync(UserManager<ApplicationUser> userManager, ClaimsPrincipal principal)
    {
        var user = await userManager.GetUserAsync(principal);
        if (user == null)
        {
            return false;
        }
        else if (!userManager.SupportsUserSecurityStamp)
        {
            return true;
        }
        else
        {
            var principalStamp = principal.FindFirstValue(_options.ClaimsIdentity.SecurityStampClaimType);
            var userStamp = await userManager.GetSecurityStampAsync(user);
            return principalStamp == userStamp;
        }
    }
}
