using LCU.API.Internal.Operations.IncentiveApi.Services;
using LCU.Library.Internal.IncentiveApiModels.Entities;
using LCU.Library.Internal.IncentiveApiModels.Enums;
using Moq;
using NUnit.Framework;
using System.Collections.Generic;
using System.Threading.Tasks;
using System.Linq;
using LCU.API.Internal.Operations.IncentiveApiLib.Repositories;
using LCU.API.Internal.Operations.IncentiveApi.Exceptions;

namespace Application.UnitTests.Services
{
    public class CommissionServiceTest
    {
        private CommissionService _service;
        private Mock<ICommissionRepository> _mockCommissionRepository;
        private Mock<IUnitOfWork> _mockUnitOfWork;

        [SetUp]
        public void Setup()
        {
            _mockCommissionRepository = new Mock<ICommissionRepository>();
            _mockUnitOfWork = new Mock<IUnitOfWork>();
            _service = new CommissionService(_mockCommissionRepository.Object, _mockUnitOfWork.Object);
        }

        [Test]
        public async Task GetCommissionsAsync_ReturnsCommissionsFromRepo()
        {
            var commissions = new List<Commission>
            {
                new Commission
                {
                    Id = 1,
                    Product = Product.ATMCard,
                    RatePerProduct = 5,
                    Role = Role.Teller
                },
                new Commission
                {
                    Id = 2,
                    Product = Product.CheckCard,
                    RatePerProduct = 10,
                    Role = Role.ABM
                }
            }.AsReadOnly();
            _mockCommissionRepository.Setup(repo => repo.GetCommissionsAsync()).ReturnsAsync(commissions);

            var result = await _service.GetCommissionsAsync();

            Assert.NotNull(result);
            Assert.AreEqual(2, result.Count);
            Assert.AreEqual(commissions[0].Id, result.ElementAt(0).Id);
            Assert.AreEqual(commissions[0].Product, result.ElementAt(0).Product);
            Assert.AreEqual(commissions[0].RatePerProduct, result.ElementAt(0).RatePerProduct);
            Assert.AreEqual(commissions[0].Role, result.ElementAt(0).Role);
            Assert.AreEqual(commissions[1].Id, result.ElementAt(1).Id);
            Assert.AreEqual(commissions[1].Product, result.ElementAt(1).Product);
            Assert.AreEqual(commissions[1].RatePerProduct, result.ElementAt(1).RatePerProduct);
            Assert.AreEqual(commissions[1].Role, result.ElementAt(1).Role);
        }

        [Test]
        public async Task SaveCommissionsAsync_NewCommission_CallRepoWithCommissionToSave()
        {
            var actualUpdates = new List<Commission>();
            var newCommission = new Commission
            {
                Id = 0,
                Product = Product.ATMCard,
                RatePerProduct = 5,
                Role = Role.Teller
            };

            var commissionsToUpdate = new List<Commission> { newCommission };

            _mockCommissionRepository.Setup(repo => repo.FindExistingCommission(newCommission.Role, newCommission.Product))
                .ReturnsAsync((Commission)null);
            _mockCommissionRepository.Setup(repo => repo.SaveCommission(newCommission));

            await _service.SaveCommissionsAsync(commissionsToUpdate);

            _mockCommissionRepository.Verify(repo => repo.FindExistingCommission(newCommission.Role, newCommission.Product), Times.Once);
            _mockCommissionRepository.Verify(repo => repo.SaveCommission(newCommission), Times.Once);
            _mockUnitOfWork.Verify(context => context.CompleteAsync(), Times.Once);
        }

        [Test]
        public void SaveCommissionsAsync_NewCommissionMatchInRepo_ThrowsCommissionExistsException()
        {
            var newCommission = new Commission
            {
                Id = 0,
                Product = Product.CheckCard,
                RatePerProduct = 10,
                Role = Role.ABM
            };
            var commissions = new List<Commission> { newCommission };

            var existingInRepo =  new Commission
            {
                Id = 1,
                Product = Product.CheckCard,
                RatePerProduct = 15,
                Role = Role.ABM
            };

            _mockCommissionRepository.Setup(repo => repo.FindExistingCommission(newCommission.Role, newCommission.Product))
                .ReturnsAsync(existingInRepo);

            var ex = Assert.ThrowsAsync<CommissionExistsException>(async () =>
            {
                await _service.SaveCommissionsAsync(commissions);
            });

            Assert.AreEqual("Commission already exists for Role=ABM, Product=CheckCard", ex.Message);
            _mockCommissionRepository.Verify(repo => repo.FindExistingCommission(newCommission.Role, newCommission.Product), Times.Once);
            _mockCommissionRepository.Verify(repo => repo.SaveCommission(It.IsAny<Commission>()), Times.Never);
            _mockUnitOfWork.Verify(context => context.CompleteAsync(), Times.Never);
            _mockCommissionRepository.VerifyNoOtherCalls();
        }

        [Test]
        public async Task SaveCommissionsAsync_UpdateCommission_SetsRate()
        {
            var updates = new Commission
            {
                Id = 1,
                Product = Product.CheckCard,
                RatePerProduct = 20,
                Role = Role.ABM
            };
            var commissions = new List<Commission> { updates };

            var commissionToUpdate = new Commission
            {
                Id = 1,
                Product = Product.CheckCard,
                RatePerProduct = 15,
                Role = Role.ABM
            };
            Assert.AreEqual(15, commissionToUpdate.RatePerProduct);

            _mockCommissionRepository.Setup(repo => repo.FindExistingCommission(updates.Id))
                .ReturnsAsync(commissionToUpdate);

            await _service.SaveCommissionsAsync(commissions);

            Assert.AreEqual(20, commissionToUpdate.RatePerProduct);
            _mockCommissionRepository.Verify(repo => repo.FindExistingCommission(updates.Id), Times.Once);
            _mockUnitOfWork.Verify(context => context.CompleteAsync(), Times.Once);
            _mockCommissionRepository.VerifyNoOtherCalls();
        }
    }
}