using AutoMapper;
using HardwarePerformance.Models;
using HardwarePerformance.Models.DTOs;
using HardwarePerformance.Services;
using Moq;

namespace HardwarePerformance.Tests.Services
{
    public class ComparisonServiceTests
    {
        private readonly Mock<IProductRepository> _mockProductRepository;
        private readonly Mock<IMapper> _mockMapper;
        private readonly ComparisonService _comparisonService;

        public ComparisonServiceTests()
        {
            _mockProductRepository = new Mock<IProductRepository>();
            _mockMapper = new Mock<IMapper>();
            _comparisonService = new ComparisonService(_mockProductRepository.Object, _mockMapper.Object);
        }

        [Fact]
        public async Task CompareProductsAsync_ValidProductIds_ReturnsComparisonData()
        {
            // Arrange
            var productIds = new List<int> { 1, 2 };
            
            var products = new List<Product>
            {
                new Product 
                { 
                    Id = 1, 
                    Name = "Intel Core i9", 
                    Manufacturer = "Intel",
                    CategoryId = 1,
                    CurrentRank = 1,
                    ReleaseDate = DateTime.Now.AddMonths(-6),
                    Price = 500,
                    PerformanceScore = 4000,
                    PerformanceScores = new List<PerformanceScore>
                    {
                        new PerformanceScore { Id = 1, ProductId = 1, TestType = "Single-Core", Score = 1500 },
                        new PerformanceScore { Id = 2, ProductId = 1, TestType = "Multi-Core", Score = 8000 }
                    },
                    Specifications = new List<Specification>
                    {
                        new Specification { Id = 1, ProductId = 1, Name = "Cores", Value = "8" },
                        new Specification { Id = 2, ProductId = 1, Name = "Threads", Value = "16" }
                    }
                },
                new Product 
                { 
                    Id = 2, 
                    Name = "AMD Ryzen 9", 
                    Manufacturer = "AMD",
                    CategoryId = 1,
                    CurrentRank = 2,
                    ReleaseDate = DateTime.Now.AddMonths(-4),
                    Price = 450,
                    PerformanceScore = 3800,
                    PerformanceScores = new List<PerformanceScore>
                    {
                        new PerformanceScore { Id = 3, ProductId = 2, TestType = "Single-Core", Score = 1400 },
                        new PerformanceScore { Id = 4, ProductId = 2, TestType = "Multi-Core", Score = 7500 }
                    },
                    Specifications = new List<Specification>
                    {
                        new Specification { Id = 3, ProductId = 2, Name = "Cores", Value = "8" },
                        new Specification { Id = 4, ProductId = 2, Name = "Threads", Value = "16" }
                    }
                }
            };

            var productDtos = new List<ProductDto>
            {
                new ProductDto 
                { 
                    Id = 1, 
                    Name = "Intel Core i9", 
                    Manufacturer = "Intel",
                    CategoryId = 1,
                    CurrentRank = 1,
                    ReleaseDate = DateTime.Now.AddMonths(-6),
                    Price = 500,
                    PerformanceScore = 4000,
                    PerformanceScores = new List<PerformanceScore>
                    {
                        new PerformanceScore { Id = 1, ProductId = 1, TestType = "Single-Core", Score = 1500 },
                        new PerformanceScore { Id = 2, ProductId = 1, TestType = "Multi-Core", Score = 8000 }
                    },
                    Specifications = new List<Specification>
                    {
                        new Specification { Id = 1, ProductId = 1, Name = "Cores", Value = "8" },
                        new Specification { Id = 2, ProductId = 1, Name = "Threads", Value = "16" }
                    }
                },
                new ProductDto 
                { 
                    Id = 2, 
                    Name = "AMD Ryzen 9", 
                    Manufacturer = "AMD",
                    CategoryId = 1,
                    CurrentRank = 2,
                    ReleaseDate = DateTime.Now.AddMonths(-4),
                    Price = 450,
                    PerformanceScore = 3800,
                    PerformanceScores = new List<PerformanceScore>
                    {
                        new PerformanceScore { Id = 3, ProductId = 2, TestType = "Single-Core", Score = 1400 },
                        new PerformanceScore { Id = 4, ProductId = 2, TestType = "Multi-Core", Score = 7500 }
                    },
                    Specifications = new List<Specification>
                    {
                        new Specification { Id = 3, ProductId = 2, Name = "Cores", Value = "8" },
                        new Specification { Id = 4, ProductId = 2, Name = "Threads", Value = "16" }
                    }
                }
            };

            _mockProductRepository.Setup(repo => repo.GetByIdsAsync(productIds))
                .ReturnsAsync(products);

            _mockMapper.Setup(m => m.Map<List<ProductDto>>(products))
                .Returns(productDtos);

            // Act
            var result = await _comparisonService.CompareProductsAsync(productIds);

            // Assert
            Assert.NotNull(result);
            Assert.Equal(2, result.Products.Count);
            Assert.NotNull(result.ComparisonMatrix);
            _mockProductRepository.Verify(repo => repo.GetByIdsAsync(productIds), Times.Once);
            _mockMapper.Verify(m => m.Map<List<ProductDto>>(products), Times.Once);
        }

        [Fact]
        public async Task CompareProductsAsync_EmptyProductIds_ThrowsArgumentException()
        {
            // Arrange
            var productIds = new List<int>();

            // Act & Assert
            await Assert.ThrowsAsync<ArgumentException>(async () => 
                await _comparisonService.CompareProductsAsync(productIds));
        }

        [Fact]
        public async Task CompareProductsAsync_TooManyProductIds_ThrowsArgumentException()
        {
            // Arrange
            var productIds = new List<int> { 1, 2, 3, 4, 5 };

            // Act & Assert
            await Assert.ThrowsAsync<ArgumentException>(async () => 
                await _comparisonService.CompareProductsAsync(productIds));
        }

        [Fact]
        public async Task CompareProductsAsync_NonExistingProductIds_ThrowsKeyNotFoundException()
        {
            // Arrange
            var productIds = new List<int> { 1, 2 };

            _mockProductRepository.Setup(repo => repo.GetByIdsAsync(productIds))
                .ReturnsAsync(new List<Product>());

            // Act & Assert
            await Assert.ThrowsAsync<KeyNotFoundException>(async () => 
                await _comparisonService.CompareProductsAsync(productIds));
        }
    }
}