// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System.Collections.Generic;
using Microsoft.AspNetCore.Http;
using Xunit;

namespace Microsoft.AspNetCore.Routing.Matching
{
    public class EndpointMetadataComparerTest
    {
        [Fact]
        public void Compare_EndpointWithMetadata_MoreSpecific()
        {
            // Arrange
            var endpoint1 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { new TestMetadata(), }), "test1");
            var endpoint2 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] {  }), "test2");

            // Act
            var result = EndpointMetadataComparer<TestMetadata>.Default.Compare(endpoint1, endpoint2);

            // Assert
            Assert.Equal(-1, result);
        }

        [Fact]
        public void Compare_EndpointWithMetadata_ReverseOrder_MoreSpecific()
        {
            // Arrange
            var endpoint1 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { }), "test1");
            var endpoint2 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { new TestMetadata(), }), "test2");

            // Act
            var result = EndpointMetadataComparer<TestMetadata>.Default.Compare(endpoint1, endpoint2);

            // Assert
            Assert.Equal(1, result);
        }

        [Fact]
        public void Compare_BothEndpointsWithMetadata_Equal()
        {
            // Arrange
            var endpoint1 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { new TestMetadata(), }), "test1");
            var endpoint2 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { new TestMetadata(), }), "test2");

            // Act
            var result = EndpointMetadataComparer<TestMetadata>.Default.Compare(endpoint1, endpoint2);

            // Assert
            Assert.Equal(0, result);
        }

        [Fact]
        public void Compare_BothEndpointsWithoutMetadata_Equal()
        {
            // Arrange
            var endpoint1 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { }), "test1");
            var endpoint2 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { }), "test2");

            // Act
            var result = EndpointMetadataComparer<TestMetadata>.Default.Compare(endpoint1, endpoint2);

            // Assert
            Assert.Equal(0, result);
        }

        [Fact]
        public void Sort_EndpointWithMetadata_FirstInList()
        {
            // Arrange
            var endpoint1 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { new TestMetadata(), }), "test1");
            var endpoint2 = new Endpoint(TestConstants.EmptyRequestDelegate, new EndpointMetadataCollection(new object[] { }), "test2");

            var list = new List<Endpoint>() { endpoint2, endpoint1, };

            // Act
            list.Sort(EndpointMetadataComparer<TestMetadata>.Default);

            // Assert
            Assert.Collection(
                list,
                e => Assert.Same(endpoint1, e),
                e => Assert.Same(endpoint2, e));
        }

        private class TestMetadata
        {
        }
    }
}