Budgeteer/BudgetApp.Tests/Services/AccountServiceTests.cs

using BudgetApp.Data;
using BudgetApp.Services;
using BudgetApp.Tests.Helpers;
using Xunit;

namespace BudgetApp.Tests.Services;

public class AccountServiceTests
{
    [Fact]
    public async Task GetAccountsAsync_ReturnsOnlyUserAccounts()
    {
        using var factory = new TestDbContextFactory();
        using (var ctx = factory.CreateContext())
        {
            ctx.Accounts.AddRange(
                new Account { Name = "Mine", UserId = TestDbContextFactory.TestUserId },
                new Account { Name = "Theirs", UserId = TestDbContextFactory.OtherUserId });
            await ctx.SaveChangesAsync();
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);

        var result = await service.GetAccountsAsync(TestDbContextFactory.TestUserId);

        Assert.Single(result);
        Assert.Equal("Mine", result[0].Name);
    }

    [Fact]
    public async Task GetAccountsAsync_OrderedByName()
    {
        using var factory = new TestDbContextFactory();
        using (var ctx = factory.CreateContext())
        {
            ctx.Accounts.AddRange(
                new Account { Name = "Zebra", UserId = TestDbContextFactory.TestUserId },
                new Account { Name = "Alpha", UserId = TestDbContextFactory.TestUserId });
            await ctx.SaveChangesAsync();
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);

        var result = await service.GetAccountsAsync(TestDbContextFactory.TestUserId);

        Assert.Equal("Alpha", result[0].Name);
        Assert.Equal("Zebra", result[1].Name);
    }

    [Fact]
    public async Task GetAccountAsync_ReturnsMatchingAccount()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "Test", UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);

        var result = await service.GetAccountAsync(accountId, TestDbContextFactory.TestUserId);

        Assert.NotNull(result);
        Assert.Equal("Test", result.Name);
    }

    [Fact]
    public async Task GetAccountAsync_WrongUser_ReturnsNull()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "Test", UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);

        var result = await service.GetAccountAsync(accountId, TestDbContextFactory.OtherUserId);

        Assert.Null(result);
    }

    [Fact]
    public async Task CreateAccountAsync_AddsToDatabase()
    {
        using var factory = new TestDbContextFactory();
        using var context = factory.CreateContext();
        var service = new AccountService(context);

        var account = new Account { Name = "New", UserId = TestDbContextFactory.TestUserId, CurrencyCode = "GBP" };
        await service.CreateAccountAsync(account);

        using var verifyCtx = factory.CreateContext();
        Assert.Single(verifyCtx.Accounts);
    }

    [Fact]
    public async Task UpdateBalanceAsync_UpdatesBalance()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "Test", CurrentBalance = 100m, UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);
        await service.UpdateBalanceAsync(accountId, TestDbContextFactory.TestUserId, 250m);

        using var verifyCtx = factory.CreateContext();
        var updated = verifyCtx.Accounts.Single();
        Assert.Equal(250m, updated.CurrentBalance);
    }

    [Fact]
    public async Task UpdateBalanceAsync_WrongUser_DoesNothing()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "Test", CurrentBalance = 100m, UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);
        await service.UpdateBalanceAsync(accountId, TestDbContextFactory.OtherUserId, 999m);

        using var verifyCtx = factory.CreateContext();
        Assert.Equal(100m, verifyCtx.Accounts.Single().CurrentBalance);
    }

    [Fact]
    public async Task UpdateAccountDetailsAsync_UpdatesFields()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "Old", Color = "#000", CurrencyCode = "GBP", UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);
        await service.UpdateAccountDetailsAsync(accountId, TestDbContextFactory.TestUserId, "New", "#fff", "USD");

        using var verifyCtx = factory.CreateContext();
        var updated = verifyCtx.Accounts.Single();
        Assert.Equal("New", updated.Name);
        Assert.Equal("#fff", updated.Color);
        Assert.Equal("USD", updated.CurrencyCode);
    }

    [Fact]
    public async Task UpdateAccountDetailsAsync_WrongUser_DoesNothing()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "Original", Color = "#000", CurrencyCode = "GBP", UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);
        await service.UpdateAccountDetailsAsync(accountId, TestDbContextFactory.OtherUserId, "Hacked", "#fff", "USD");

        using var verifyCtx = factory.CreateContext();
        Assert.Equal("Original", verifyCtx.Accounts.Single().Name);
    }

    [Fact]
    public async Task DeleteAccountAsync_RemovesAccount()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "ToDelete", UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);
        await service.DeleteAccountAsync(accountId, TestDbContextFactory.TestUserId);

        using var verifyCtx = factory.CreateContext();
        Assert.Empty(verifyCtx.Accounts);
    }

    [Fact]
    public async Task DeleteAccountAsync_WrongUser_DoesNothing()
    {
        using var factory = new TestDbContextFactory();
        int accountId;
        using (var ctx = factory.CreateContext())
        {
            var account = new Account { Name = "Protected", UserId = TestDbContextFactory.TestUserId };
            ctx.Accounts.Add(account);
            await ctx.SaveChangesAsync();
            accountId = account.Id;
        }

        using var context = factory.CreateContext();
        var service = new AccountService(context);
        await service.DeleteAccountAsync(accountId, TestDbContextFactory.OtherUserId);

        using var verifyCtx = factory.CreateContext();
        Assert.Single(verifyCtx.Accounts);
    }
}