classlib/ExpenseTracker.Application/Accounts/Queries/Charts/DailyTransactionsBarChart.cs

namespace ExpenseTracker.Application.Accounts.Queries.Charts;

public class DailyTransactionsBarChart
{
    public DailyTransactionsBarChart(IEnumerable<IGrouping<DateTime, double>> groupings, DateOnly fromDate, DateOnly toDate)
    {
        var days = toDate.DayNumber - fromDate.DayNumber;

        var dateAmount = new Dictionary<DateOnly, double>(days);

        for (int i = 0; i < days; i++)
        {
            dateAmount.Add(fromDate.AddDays(i), 0);
        }

        foreach (var group in groupings)
        {
            var date = DateOnly.FromDateTime(group.Key);
            var amount = group.Aggregate(0.0, (a, x) => a + x);

            dateAmount[date] = amount;
        }

        Dates = dateAmount.Keys.ToList();
        Amounts = dateAmount.Values.ToList();
    }

    public double MinimumAmount => Amounts.Min();

    public double MaximumAmount => Amounts.Max();

    public double AverageAmount  => Double.Round(TotalAmount / Amounts.Count(), 4);

    public double TotalAmount => Amounts.Aggregate(0.0, (a, x) => a +x);

    public IEnumerable<DateOnly> Dates { get; set; }

    public IEnumerable<double> Amounts { get; set; }
}