Program.cs

using Microsoft.EntityFrameworkCore;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.IdentityModel.Tokens;
using Npgsql;
using play929_server.Data;
using play929_server.Services;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.SignalR;
using play929_server.Hubs;
using play929_server.Middlewares;
using System.Text;
using AspNetCoreRateLimit;

var builder = WebApplication.CreateBuilder(args);

// Add essential services to the DI container
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

// Register HttpClient
builder.Services.AddHttpClient(); 
builder.Services.AddMemoryCache();

// Add rate limiting services
builder.Services.AddInMemoryRateLimiting(); 
builder.Services.AddSingleton<IRateLimitConfiguration, RateLimitConfiguration>();  

// Configure PostgreSQL DbContext with dynamic connection string handling
string connectionString = GetConnectionString(builder.Environment);

builder.Services.AddAuthentication(options =>
{
    options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
    options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(options =>
{
    ConfigureJwtBearerOptions(options);
});

// Register DbContext with the resolved connection string
builder.Services.AddDbContext<ApplicationDbContext>(options =>
    options.UseNpgsql(connectionString));

// Register application services and controllers
builder.Services.AddControllers();
builder.Services.AddScoped<PostgreSQLHelper>();
builder.Services.AddScoped<IUserService, UserService>(); 

// Add SignalR for real-time communication
builder.Services.AddSignalR();

// Configure CORS policy for authorized domains
builder.Services.AddCors(options =>
{
    options.AddPolicy("AllowPlay929AndAuth", builder =>
    {
        builder.WithOrigins("https://play929.com" , "https://dashboard.play929.com", "https://portal.play929.com", "http://localhost:3000")
               .AllowAnyHeader()
               .AllowAnyMethod()
               .AllowCredentials();
    });
});

var app = builder.Build();

// Enable rate limiting globally
app.UseIpRateLimiting();  

// Configure static file serving and apply migrations
app.UseStaticFiles();
ApplyDatabaseMigrations(app);

// Enable Swagger UI in development environment
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();
app.UseCors("AllowPlay929AndAuth");
app.UseRouting();
app.UseMiddleware<TokenMiddleware>();


app.UseAuthentication();
app.UseAuthorization();

// Map SignalR hubs
app.MapHub<ChatHub>("/chatHub");
app.MapHub<GameHub>("/gameHub");
app.MapHub<GameHub>("/adminHub");

// Map controllers
app.MapControllers();

app.Run();

/// <summary>
/// Retrieves the appropriate database connection string based on the environment.
/// </summary>
string GetConnectionString(IHostEnvironment environment)
{

    // Use the default connection string for local development
    return builder.Configuration.GetConnectionString("DefaultConnection");
}

/// <summary>
/// Constructs a PostgreSQL connection string from a given URI.
/// </summary>
string BuildNpgsqlConnectionString(Uri databaseUri)
{
    var userInfo = databaseUri.UserInfo.Split(':');
    return new NpgsqlConnectionStringBuilder
    {
        Host = databaseUri.Host,
        Port = databaseUri.Port,
        Username = userInfo[0],
        Password = userInfo[1],
        Database = databaseUri.AbsolutePath.TrimStart('/'),
        SslMode = SslMode.Require,
        TrustServerCertificate = true
    }.ToString();
}

/// <summary>
/// Configures JWT Bearer Authentication options.
/// </summary>
void ConfigureJwtBearerOptions(JwtBearerOptions options)
{
    options.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = true,
        ValidateAudience = true,
        ValidateLifetime = true,
        ValidateIssuerSigningKey = true,
        ValidIssuer = "https://play929.com", 
        ValidAudience = "https://auth.play929.com", 
        IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("MySuperSecretJWTKeyThatIs32CharsLongOrMore!"))
    };
}

/// <summary>
/// Applies pending database migrations.
/// </summary>
void ApplyDatabaseMigrations(WebApplication app)
{
    using var scope = app.Services.CreateScope();
    var dbContext = scope.ServiceProvider.GetRequiredService<ApplicationDbContext>();
    dbContext.Database.Migrate();
}