// 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.IO;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.AspNet.HttpFeature;
using Microsoft.AspNet.PipelineCore;
using Microsoft.AspNet.Routing;
using Moq;
using Xunit;

namespace Microsoft.AspNet.Mvc
{
    public class FilePathResultTest
    {
        [Fact]
        public void Constructor_SetsFileName()
        {
            // Arrange & Act
            var path = Path.GetFullPath("helllo.txt");
            var result = new FilePathResult(path, "text/plain");

            // Act & Assert
            Assert.Equal(path, result.FileName);
        }

        [Fact]
        public async Task ExecuteResultAsync_FallsbackToStreamCopy_IfNoIHttpSendFilePresent()
        {
            // Arrange
            var path = Path.GetFullPath(Path.Combine("TestFiles", "FilePathResultTestFile.txt"));
            var result = new FilePathResult(path, "text/plain");

            var httpContext = new DefaultHttpContext();
            httpContext.Response.Body = new MemoryStream();

            var context = new ActionContext(httpContext, new RouteData(), new ActionDescriptor());

            // Act
            await result.ExecuteResultAsync(context);
            httpContext.Response.Body.Position = 0;

            // Assert
            Assert.NotNull(httpContext.Response.Body);
            var contents = await new StreamReader(httpContext.Response.Body).ReadToEndAsync();
            Assert.Equal("FilePathResultTestFile contents", contents);
        }

        [Fact]
        public async Task ExecuteResultAsync_CallsSendFileAsync_IfIHttpSendFilePresent()
        {
            // Arrange
            var path = Path.GetFullPath(Path.Combine("TestFiles", "FilePathResultTestFile.txt"));
            var result = new FilePathResult(path, "text/plain");

            var sendFileMock = new Mock<IHttpSendFileFeature>();
            sendFileMock
                .Setup(s => s.SendFileAsync(path, 0, null, CancellationToken.None))
                .Returns(Task.FromResult<int>(0));

            var httpContext = new DefaultHttpContext();
            httpContext.SetFeature(sendFileMock.Object);

            var context = new ActionContext(httpContext, new RouteData(), new ActionDescriptor());

            // Act
            await result.ExecuteResultAsync(context);

            // Assert
            sendFileMock.Verify();
        }
    }
}