using System;
using System.Linq;

namespace LCU.Library.Internal.IncentiveApiModels.Entities
{
    public static class PayoutProfileExtensions
    {
        public static PayoutRange FindPayoutRange(this PayoutProfile profile, double percentage, DateTime runDate)
        {
            var percentageToHundreds = Math.Truncate(100 * percentage) / 100;
            var defaultPayout = profile.Payouts.First(defaultPayout => defaultPayout.Key == DateTime.MinValue).Value;
            if (profile.Payouts.Count == 1)
            {
                return defaultPayout.FirstOrDefault(payoutRange => payoutRange.IsInRange(percentageToHundreds));
            }

            var payout = profile.Payouts.FirstOrDefault(payout =>
            {
                var dateTimeOfPayout = payout.Key;
                return dateTimeOfPayout.Month == runDate.Month && dateTimeOfPayout.Year == runDate.Year;
            }).Value;

            var t = payout == null ? defaultPayout.FirstOrDefault(payoutRange => payoutRange.IsInRange(percentageToHundreds)) : payout.FirstOrDefault(payoutRange => payoutRange.IsInRange(percentageToHundreds));
            return t;
        }

        public static decimal CalculateLineItemPayout(this PayoutProfile profile, int goal, decimal actual, DateTime runDate, decimal payoutPercent = 100)
        {
            if (profile == null)
            {
                throw new Exception("Attempt to calculate payout with null profile");
            }

            if (goal == 0) return 0;

            var goalPercentage = (double)actual / goal;
            var payoutRange = profile.FindPayoutRange(goalPercentage, runDate);

            if (payoutRange == null)
            {
                return 0;
            }

            decimal payoutAmt = payoutRange.Payout;
            if (profile.PayEach)
            {
                payoutAmt *= actual;
            }

            double payoutPercentage = (double)payoutPercent / 100;
            double finalPayout = (double)payoutAmt * payoutPercentage;
            payoutAmt = (decimal)Math.Round(finalPayout, 2);

            return payoutAmt;
        }
    }
}