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

using System.Globalization;
using System.IO;
using System.Runtime.Serialization;
using System.Text;
using System.Xml;
using Microsoft.AspNet.Mvc.ModelBinding;
using Xunit;

namespace Microsoft.AspNet.Mvc
{
    public class SerializableErrorTests
    {
        [Fact]
        public void ConvertsModelState_To_Dictionary()
        {
            // Arrange
            var modelState = new ModelStateDictionary();
            modelState.AddModelError("key1", "Test Error 1");
            modelState.AddModelError("key1", "Test Error 2");
            modelState.AddModelError("key2", "Test Error 3");

            // Act
            var serializableError = new SerializableError(modelState);

            // Assert
            var arr = Assert.IsType<string[]>(serializableError["key1"]);
            Assert.Equal("Test Error 1", arr[0]);
            Assert.Equal("Test Error 2", arr[1]);
            Assert.Equal("Test Error 3", (serializableError["key2"] as string[])[0]);
        }

        [Fact]
        public void LookupIsCaseInsensitive()
        {
            // Arrange
            var modelState = new ModelStateDictionary();
            modelState.AddModelError("key1", "x");

            // Act
            var serializableError = new SerializableError(modelState);

            // Assert
            var arr = Assert.IsType<string[]>(serializableError["KEY1"]);
            Assert.Equal("x", arr[0]);
        }

        [Fact]
        public void ConvertsModelState_To_Dictionary_AddsDefaultValuesWhenErrorsAreAbsent()
        {
            // Arrange
            var modelState = new ModelStateDictionary();
            modelState.AddModelError("key1", "");

            // Act
            var serializableError = new SerializableError(modelState);

            // Assert
            var arr = Assert.IsType<string[]>(serializableError["key1"]);
            Assert.Equal("The input was not valid.", arr[0]);
        }

        [Fact]
        public void DoesNotThrowOnValidModelState()
        {
            // Arrange, Act & Assert (does not throw)
            new SerializableError(new ModelStateDictionary());
        }

        [Fact]
        public void DoesNotAddEntries_IfNoErrorsArePresent()
        {
            // Arrange
            var modelState = new ModelStateDictionary();
            modelState.Add(
                "key1",
                new ModelState() { Value = new ValueProviderResult("foo", "foo", CultureInfo.InvariantCulture) });
            modelState.Add(
                "key2",
                new ModelState() { Value = new ValueProviderResult("bar", "bar", CultureInfo.InvariantCulture) });

            // Act
            var serializableError = new SerializableError(modelState);

            // Assert
            Assert.Equal(0, serializableError.Count);
        }

        [Fact]
        public void GetSchema_Returns_Null()
        {
            // Arrange
            var modelState = new ModelStateDictionary();
            // To make modelState invalid.
            modelState.AddModelError("key1", "Test Error 1");
            var serializableError = new SerializableError(modelState);

            // Act & Assert
            Assert.Null(serializableError.GetSchema());
        }

        [Fact]
        public void WriteXml_WritesValidXml()
        {
            // Arrange
            var modelState = new ModelStateDictionary();
            modelState.AddModelError("key1", "Test Error 1");
            modelState.AddModelError("key1", "Test Error 2");
            modelState.AddModelError("key2", "Test Error 3");
            var serializableError = new SerializableError(modelState);
            var outputStream = new MemoryStream();

            // Act
            using (var xmlWriter = XmlWriter.Create(outputStream))
            {
                var dataContractSerializer = new DataContractSerializer(typeof(SerializableError));
                dataContractSerializer.WriteObject(xmlWriter, serializableError);
            }
            outputStream.Position = 0;
            var res = new StreamReader(outputStream, Encoding.UTF8).ReadToEnd();

            // Assert
            Assert.Equal("<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
                "<Error><key1>Test Error 1 Test Error 2</key1><key2>Test Error 3</key2></Error>", res);
        }

        [Fact]
        public void ReadXml_ReadsSerializableErrorXml()
        {
            // Arrange
            var serializableErrorXml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
                "<Error><key1>Test Error 1 Test Error 2</key1><key2>Test Error 3</key2></Error>";
            var serializer = new DataContractSerializer(typeof(SerializableError));

            // Act
            var errors = (SerializableError)serializer.ReadObject(
                new MemoryStream(Encoding.UTF8.GetBytes(serializableErrorXml)));

            // Assert
            Assert.Equal("Test Error 1 Test Error 2", errors["key1"]);
            Assert.Equal("Test Error 3", errors["key2"]);
        }
    }
}