Program.cs

using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.IdentityModel.Tokens;
using Microsoft.Extensions.Configuration;
using System.Text;
using ChatBot.AppCode;
using ChatBot.Controllers;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
builder.Services.AddControllersWithViews();
builder.Services.AddHttpClient();
builder.Services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
builder.Services.AddScoped<SessionAdmin>();
builder.Services.AddScoped<ISessionService, SessionService>();

// JWT Authentication
var jwtSecretKey = builder.Configuration["Jwt:SecretKey"];
if (string.IsNullOrEmpty(jwtSecretKey))
{
    throw new InvalidOperationException("JWT Secret Key is missing. Ensure it is set in the environment or appsettings.json.");
}

builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
    .AddJwtBearer(options =>
    {
        options.TokenValidationParameters = new TokenValidationParameters
        {
            ValidateIssuer = true,
            ValidateAudience = true,
            ValidateLifetime = true,
            ValidateIssuerSigningKey = true,
            ValidIssuer = builder.Configuration["Jwt:Issuer"],
            ValidAudience = builder.Configuration["Jwt:Audience"],
            IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(jwtSecretKey))
        };
    });

// CSRF protection (Antiforgery), if necessary for form-based interactions
builder.Services.AddAntiforgery(options =>
{
    options.HeaderName = "X-XSRF-TOKEN";
    options.Cookie.Name = ".AspNetCore.Antiforgery";
});

// Session configuration
builder.Services.AddSession(options =>
{
    options.IdleTimeout = TimeSpan.FromMinutes(5);
    options.Cookie.HttpOnly = true;
    options.Cookie.IsEssential = true;
});

var app = builder.Build();

// Configure the HTTP request pipeline.
if (!app.Environment.IsDevelopment())
{
    app.UseExceptionHandler("/Home/Error");
    app.UseHsts();
}

app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseSession();

// Authentication and Authorization middleware
app.UseAuthentication();
app.UseAuthorization();

app.UseRouting();

app.MapControllerRoute(
    name: "default",
    pattern: "{controller=Home}/{action=Index}/{id?}");

app.Run();