Program.cs

using EmployeeManagementSystem.Data;
using EmployeeManagementSystem.Models.Entities;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using Microsoft.IdentityModel.Tokens;
using System.Text;
using Microsoft.OpenApi.Models;
using EmployeeManagementSystem.Repositories.Interfaces;
using EmployeeManagementSystem.Repositories;

var builder = WebApplication.CreateBuilder(args);

DotNetEnv.Env.Load();

// Add services to the container.
builder.Services.AddDbContext<ApplicationDbContext>(options =>
    options.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection")));

builder.Services.AddIdentity<ApplicationUser, IdentityRole>()
    .AddEntityFrameworkStores<ApplicationDbContext>()
    .AddDefaultTokenProviders();

builder.Services.AddCors(options =>
{
    options.AddPolicy("AllowLocalhost", 
        builder =>
    {
        builder.WithOrigins("http://localhost:5173")
               .AllowAnyHeader()
               .AllowAnyMethod();
    });

});


builder.Services.Configure<DataProtectionTokenProviderOptions>(options =>
        options.TokenLifespan = TimeSpan.FromMinutes(15));

builder.Services.Configure<IdentityOptions>(options =>
{
    //options.Password.RequireDigit = true;
    //options.Password.RequiredLength = 8;
    //options.Password.RequireNonAlphanumeric = true;
    //options.Password.RequireUppercase = true;
    options.Password.RequireLowercase = false;
});


builder.Services.AddAuthentication(options =>
{
    options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
    options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(options =>
{
    var jwtKey = Environment.GetEnvironmentVariable("JWT_KEY") ?? builder.Configuration["Jwt:Key"];

    if (string.IsNullOrEmpty(jwtKey))
    {
        throw new InvalidOperationException("JWT_KEY is not set.");
    }

    options.RequireHttpsMetadata = false;
    options.SaveToken = true;
    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(jwtKey)),
        ClockSkew = TimeSpan.Zero
    };
});

builder.Services.AddScoped<IEmployeeRepository, EmployeeRepository>();
builder.Services.AddScoped<ISystemUsersRepository, SystemUsersRepository>();
builder.Services.AddScoped<ISystemRolesRepository, SystemRolesRepository>();
builder.Services.AddScoped<IDepartmentRepository, DepartmentRepository>();
builder.Services.AddScoped<IUnitOfWork, UnitOfWork>();
builder.Services.AddTransient<IEmailService, EmailService>();

builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen(options =>
{
    options.SwaggerDoc("v1", new OpenApiInfo
    {
        Title = "Employee Management System",
        Version = "v1"
    });

    options.AddSecurityDefinition("Bearer", new OpenApiSecurityScheme
    {
        In = ParameterLocation.Header,
        Description = "Please enter into field the word 'Bearer' followed by a space and the JWT value",
        Name = "Authorization",
        Type = SecuritySchemeType.ApiKey,
        Scheme = "Bearer"
    });

    options.AddSecurityRequirement(new OpenApiSecurityRequirement
    {
        {
            new OpenApiSecurityScheme
            {
                Reference = new OpenApiReference
                {
                    Type = ReferenceType.SecurityScheme,
                    Id = "Bearer"
                }
            },
            new string[] { }
        }
    });
}
    );

var app = builder.Build();

using (var scope = app.Services.CreateScope())
{
    var services = scope.ServiceProvider;
    var logger = services.GetRequiredService<ILogger<Program>>();
    try
    {
        await SeedData.SeedRoles(services);
    }
    catch (Exception ex)
    {
        logger.LogError(ex, "An error occurred seeding the DB.");
    }
}

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
    app.UseDeveloperExceptionPage();
}

app.UseHttpsRedirection();

//app.UseStaticFiles();

app.UseAuthentication();

app.UseCors("AllowLocalhost");

app.UseAuthorization();

app.MapControllers();

app.Run();