using System;
using Xunit;
using Library;

namespace Library.Tests
{
    public class CalculationsTests
    {
        [Fact]
        public void AvailablePeriods_ReturnsFullDaySlots_WhenNoAppointments()
        {
            // Arrange
            var calculations = new Calculations();
            TimeSpan[] startTimes = Array.Empty<TimeSpan>();
            int[] durations = Array.Empty<int>();
            TimeSpan beginWorkingTime = new TimeSpan(9, 0, 0);
            TimeSpan endWorkingTime = new TimeSpan(17, 0, 0);
            int consultationTime = 30;

            // Act
            var result = calculations.AvailablePeriods(startTimes, durations, beginWorkingTime, endWorkingTime, consultationTime);

            // Assert
            Assert.NotEmpty(result);
            Assert.Contains("09:00-09:30", result);
            Assert.Contains("16:30-17:00", result);
        }

        [Fact]
        public void AvailablePeriods_ReturnsCorrectSlots_WhenThereAreAppointments()
        {
            // Arrange
            var calculations = new Calculations();
            TimeSpan[] startTimes = { new TimeSpan(10, 0, 0), new TimeSpan(14, 0, 0) };
            int[] durations = { 60, 60 };
            TimeSpan beginWorkingTime = new TimeSpan(9, 0, 0);
            TimeSpan endWorkingTime = new TimeSpan(17, 0, 0);
            int consultationTime = 30;

            // Act
            var result = calculations.AvailablePeriods(startTimes, durations, beginWorkingTime, endWorkingTime, consultationTime);

            // Assert
            Assert.DoesNotContain("10:00-10:30", result);
            Assert.DoesNotContain("14:00-14:30", result);
            Assert.Contains("09:00-09:30", result);
            Assert.Contains("15:30-16:00", result);
        }

        [Fact]
        public void AvailablePeriods_ReturnsEmpty_WhenNoFreeSlots()
        {
            // Arrange
            var calculations = new Calculations();
            TimeSpan[] startTimes = { new TimeSpan(9, 0, 0) };
            int[] durations = { 480 }; // 8 hours (full workday)
            TimeSpan beginWorkingTime = new TimeSpan(9, 0, 0);
            TimeSpan endWorkingTime = new TimeSpan(17, 0, 0);
            int consultationTime = 30;

            // Act
            var result = calculations.AvailablePeriods(startTimes, durations, beginWorkingTime, endWorkingTime, consultationTime);

            // Assert
            Assert.Empty(result);
        }
    }
}