Program.cs

using FitnessTrackerApi.Data;
using FitnessTrackerApi.Services;
using Microsoft.EntityFrameworkCore;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.IdentityModel.Tokens;
using System.Text;

var builder = WebApplication.CreateBuilder(args);

// Add services
builder.Services.AddControllers();
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Services.AddDbContext<FitnessContext>(opt =>
    opt.UseSqlite(builder.Configuration.GetConnectionString("DefaultConnection")));
builder.Services.AddScoped<JwtService>();
builder.Services.AddCors(options => {
    options.AddPolicy("AllowFrontend",
        builder => builder
            .WithOrigins("http://localhost:5173")
            .AllowAnyHeader()
            .AllowAnyMethod()
            .AllowCredentials()
    );
});

// JWT Auth
builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
    .AddJwtBearer(opt =>
    {
        opt.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(builder.Configuration["Jwt:Key"]!))
        };
    });

var app = builder.Build();

app.UseSwagger();
app.UseSwaggerUI();
app.UseCors("AllowFrontend");

app.UseHttpsRedirection();
app.UseAuthentication();
app.UseAuthorization();
app.MapControllers();

app.Run();