public ICollection <SolutionTransaction> GetSolutionTransactions(string settlementId)
{
var balances = _balancesProvider.GetBalances(settlementId);
var solver = new SettlementSolver(balances);
return(solver.Solve());
}
public void Solve_WhenBalancesAreZero_ReturnsEmptyList()
{
var balances = new[]
{
CreateUserBalance("A", 0),
CreateUserBalance("B", 0),
CreateUserBalance("C", 0),
CreateUserBalance("D", 0),
CreateUserBalance("E", 0),
};
var solver = new SettlementSolver(balances);
var result = solver.Solve();
Assert.Empty(result);
}
public void Solve_WhenSumOfBalancesIsNotZero()
{
var balances = new[]
{
CreateUserBalance("A", 6.67M),
CreateUserBalance("B", -3.33M),
CreateUserBalance("C", -3.33M),
};
var solver = new SettlementSolver(balances);
var result = solver.Solve();
Assert.Equal(2, result.Count);
Assert.Contains(result, t => IsTransaction(t, "B", "A", 3.33M));
Assert.Contains(result, t => IsTransaction(t, "C", "A", 3.33M));
}
public void Solve_SimpleScenario()
{
var balances = new[]
{
CreateUserBalance("A", 100),
CreateUserBalance("B", 90),
CreateUserBalance("C", -50),
CreateUserBalance("D", -50),
CreateUserBalance("E", -90),
};
var solver = new SettlementSolver(balances);
var result = solver.Solve();
Assert.Equal(3, result.Count);
Assert.Contains(result, t => IsTransaction(t, "C", "A", 50));
Assert.Contains(result, t => IsTransaction(t, "D", "A", 50));
Assert.Contains(result, t => IsTransaction(t, "E", "B", 90));
}
public void Solve_EverybodyReturnsMoneyToOnePerson()
{
var balances = new[]
{
CreateUserBalance("A", -1),
CreateUserBalance("B", -2),
CreateUserBalance("C", -3),
CreateUserBalance("D", -4),
CreateUserBalance("E", 10),
};
var solver = new SettlementSolver(balances);
var result = solver.Solve();
Assert.Equal(4, result.Count);
Assert.Contains(result, t => IsTransaction(t, "A", "E", 1));
Assert.Contains(result, t => IsTransaction(t, "B", "E", 2));
Assert.Contains(result, t => IsTransaction(t, "C", "E", 3));
Assert.Contains(result, t => IsTransaction(t, "D", "E", 4));
}
public void Solve_QuiteComplexScenario()
{
var balances = new[]
{
CreateUserBalance("A", 100),
CreateUserBalance("B", 91),
CreateUserBalance("C", -10),
CreateUserBalance("D", -11),
CreateUserBalance("E", -40),
CreateUserBalance("F", -40),
CreateUserBalance("G", -90),
};
var solver = new SettlementSolver(balances);
var result = solver.Solve();
Assert.Equal(6, result.Count);
Assert.Contains(result, t => IsTransaction(t, "G", "B", 90));
Assert.Contains(result, t => IsTransaction(t, "F", "A", 40));
Assert.Contains(result, t => IsTransaction(t, "E", "A", 40));
Assert.Contains(result, t => IsTransaction(t, "D", "A", 11));
Assert.Contains(result, t => IsTransaction(t, "C", "A", 9));
Assert.Contains(result, t => IsTransaction(t, "C", "B", 1));
}