using Microsoft.EntityFrameworkCore;

var options = new DbContextOptionsBuilder<MyDbContext>()
    .EnableSensitiveDataLogging()
    .UseCosmos("AccountEndpoint=https://localhost:8081/;AccountKey=C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==", "test")
    .Options;

using var context = new MyDbContext(options);
await context.Database.EnsureDeletedAsync();
await context.Database.EnsureCreatedAsync();

var entity = new Product
{
    TaxRate = 1/6m,
    Compound1 = 0.1m,
    Compound2 = 0.2m,
    BigDecimal = 12345678901234567890.0m
};

context.Products.Add(entity);
await context.SaveChangesAsync();
context.ChangeTracker.Clear();

// Round-trip the entity and observe accuracy loss
var loaded = await context.Products.SingleAsync();
Console.WriteLine();
Console.WriteLine($"Original TaxRate: {entity.TaxRate}");
Console.WriteLine($"Loaded TaxRate:   {loaded.TaxRate}");
Console.WriteLine($"TaxRate match:    {loaded.TaxRate == entity.TaxRate}"); // False

// Projection with mathematical operations suffers from rounding errors
var projected = await context.Products
    .Select(p => (p.Compound1 + p.Compound2) * 100000000000000000)
    .SingleAsync();

var expectedProjected = (0.1m + 0.2m) * 100000000000000000;

Console.WriteLine();
Console.WriteLine($"Expected projection (decimal math): {expectedProjected}");
Console.WriteLine($"Projected (Cosmos math): {projected}");
Console.WriteLine($"Projection match: {projected == expectedProjected}"); // False

Console.WriteLine();
Console.WriteLine("Big decimal not stored correctly:");
Console.WriteLine($"Original BigDecimal: {entity.BigDecimal}");
Console.WriteLine($"Loaded BigDecimal:   {loaded.BigDecimal}");
Console.WriteLine($"BigDecimal match:    {loaded.BigDecimal == entity.BigDecimal}"); // False

public class MyDbContext(DbContextOptions options) : DbContext(options)
{
    public DbSet<Product> Products { get; set; } = null!;
}

public class Product
{
    public int Id { get; set; }
    public decimal TaxRate { get; set; }
    public decimal Compound1 { get; set; }
    public decimal Compound2 { get; set; }
    public decimal BigDecimal { get; set; }
}