// 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 Moq;
using Xunit;

namespace Microsoft.AspNetCore.Routing
{
    public class RouteDataTest
    {
        [Fact]
        public void RouteData_DefaultPropertyValues()
        {
            // Arrange & Act
            var routeData = new RouteData();

            // Assert
            Assert.Empty(routeData.DataTokens);
            Assert.Empty(routeData.Routers);
            Assert.Empty(routeData.Values);
        }

        [Fact]
        public void RouteData_CopyConstructor()
        {
            // Arrange & Act
            var original = new RouteData();

            original.DataTokens.Add("data", "token");
            original.Routers.Add(Mock.Of<IRouter>());
            original.Values.Add("route", "value");

            var routeData = new RouteData(original);

            // Assert
            Assert.NotSame(routeData.DataTokens, original.DataTokens);
            Assert.Equal(routeData.DataTokens, original.DataTokens);
            Assert.NotSame(routeData.Routers, original.Routers);
            Assert.Equal(routeData.Routers, original.Routers);
            Assert.NotSame(routeData.Values, original.Values);
            Assert.Equal(routeData.Values, original.Values);
        }

        [Fact]
        public void RouteData_PushStateAndRestore_NullValues()
        {
            // Arrange
            var routeData = new RouteData();

            // Act
            var snapshot = routeData.PushState(null, null, null);
            var copy = new RouteData(routeData);
            snapshot.Restore();

            // Assert
            Assert.Equal(routeData.DataTokens, copy.DataTokens);
            Assert.Equal(routeData.Routers, copy.Routers);
            Assert.Equal(routeData.Values, copy.Values);
        }

        [Fact]
        public void RouteData_PushStateAndRestore_EmptyValues()
        {
            // Arrange
            var routeData = new RouteData();

            // Act
            var snapshot = routeData.PushState(null, new RouteValueDictionary(), new RouteValueDictionary());
            var copy = new RouteData(routeData);
            snapshot.Restore();

            // Assert
            Assert.Equal(routeData.DataTokens, copy.DataTokens);
            Assert.Equal(routeData.Routers, copy.Routers);
            Assert.Equal(routeData.Values, copy.Values);
        }

        // This is an important semantic for catchall parameters. A null route value shouldn't be
        // merged.
        [Fact]
        public void RouteData_PushStateAndRestore_NullRouteValueNotSet()
        {
            // Arrange
            var original = new RouteData();
            original.Values.Add("bleh", "16");

            var routeData = new RouteData(original);

            // Act
            var snapshot = routeData.PushState(
                null, 
                new RouteValueDictionary(new { bleh = (string)null }),
                new RouteValueDictionary());
            snapshot.Restore();

            // Assert
            Assert.Equal(routeData.Values, original.Values);
        }

        [Fact]
        public void RouteData_PushStateAndThenModify()
        {
            // Arrange
            var routeData = new RouteData();

            // Act
            var snapshot = routeData.PushState(null, null, null);
            routeData.DataTokens.Add("data", "token");
            routeData.Routers.Add(Mock.Of<IRouter>());
            routeData.Values.Add("route", "value");

            var copy = new RouteData(routeData);
            snapshot.Restore();

            // Assert
            Assert.Empty(routeData.DataTokens);
            Assert.NotEqual(routeData.DataTokens, copy.DataTokens);
            Assert.Empty(routeData.Routers);
            Assert.NotEqual(routeData.Routers, copy.Routers);
            Assert.Empty(routeData.Values);
            Assert.NotEqual(routeData.Values, copy.Values);
        }

        [Fact]
        public void RouteData_PushStateAndThenModify_WithInitialData()
        {
            // Arrange
            var original = new RouteData();
            original.DataTokens.Add("data", "token1");
            original.Routers.Add(Mock.Of<IRouter>());
            original.Values.Add("route", "value1");

            var routeData = new RouteData(original);

            // Act
            var snapshot = routeData.PushState(
                Mock.Of<IRouter>(),
                new RouteValueDictionary(new { route = "value2" }),
                new RouteValueDictionary(new { data = "token2" }));

            routeData.DataTokens.Add("data2", "token");
            routeData.Routers.Add(Mock.Of<IRouter>());
            routeData.Values.Add("route2", "value");

            var copy = new RouteData(routeData);
            snapshot.Restore();

            // Assert
            Assert.Equal(original.DataTokens, routeData.DataTokens);
            Assert.NotEqual(routeData.DataTokens, copy.DataTokens);
            Assert.Equal(original.Routers, routeData.Routers);
            Assert.NotEqual(routeData.Routers, copy.Routers);
            Assert.Equal(original.Values, routeData.Values);
            Assert.NotEqual(routeData.Values, copy.Values);
        }
    }
}