<!-- Licensed to the .NET Foundation under one or more agreements. The .NET Foundation licenses this file to you under the MIT license. -->
<Project>
 
  <PropertyGroup>
    <_EnableTargetFrameworkFiltering>false</_EnableTargetFrameworkFiltering>
    <_EnableTargetFrameworkFiltering Condition="'$(NoTargetFrameworkFiltering)' != 'true' and '$(DotNetTargetFrameworkFilter)' != ''">true</_EnableTargetFrameworkFiltering>
  </PropertyGroup>
 
  <PropertyGroup Condition="$(_EnableTargetFrameworkFiltering)">
    <_OriginalTargetFrameworks Condition="'$(TargetFrameworks)' != ''">$(TargetFrameworks)</_OriginalTargetFrameworks>
    <_OriginalTargetFrameworks Condition="'$(TargetFramework)' != ''">$(TargetFramework)</_OriginalTargetFrameworks>
    <_FilteredTargetFrameworks>$([MSBuild]::Unescape($([MSBuild]::FilterTargetFrameworks('$(_OriginalTargetFrameworks)', '$(DotNetTargetFrameworkFilter)'))))</_FilteredTargetFrameworks>
    <!-- Maintain usage of the original property -->
    <TargetFrameworks Condition="'$(TargetFrameworks)' != ''">$(_FilteredTargetFrameworks)</TargetFrameworks>
    <TargetFramework Condition="'$(TargetFramework)' != ''">$(_FilteredTargetFrameworks)</TargetFramework>
    <!-- If nothing left to build, exclude it! -->
    <ExcludeFromBuild Condition="'$(_FilteredTargetFrameworks)' == ''">true</ExcludeFromBuild>
  </PropertyGroup>
  
  <!-- Opt-in target to verify that a project doesn't bring in the .NET Standard 1.x dependency graph
       (usually transitively) via old dependencies. -->        
  <Target Name="FlagNetStandard1xDependencies"
          Condition="'$(FlagNetStandard1XDependencies)' == 'true'"
          AfterTargets="ResolvePackageAssets">
    <ItemGroup>
      <NetStandard1xPackage Include="
        Microsoft.Win32.Primitives;
        System.AppContext;
        System.Collections;
        System.Collections.Concurrent;
        System.Console;
        System.Diagnostics.Debug;
        System.Diagnostics.Tools;
        System.Diagnostics.Tracing;
        System.Globalization;
        System.Globalization.Calendars;
        System.IO;
        System.IO.Compression;
        System.IO.Compression.ZipFile;
        System.IO.FileSystem;
        System.IO.FileSystem.Primitives;
        System.Linq;
        System.Linq.Expressions;
        System.Net.Http;
        System.Net.Primitives;
        System.Net.Sockets;
        System.ObjectModel;
        System.Reflection;
        System.Reflection.Extensions;
        System.Reflection.Primitives;
        System.Resources.ResourceManager;
        System.Runtime;
        System.Runtime.Extensions;
        System.Runtime.Handles;
        System.Runtime.InteropServices;
        System.Runtime.InteropServices.RuntimeInformation;
        System.Runtime.Numerics;
        System.Security.Cryptography.Algorithms;
        System.Security.Cryptography.Encoding;
        System.Security.Cryptography.Primitives;
        System.Security.Cryptography.X509Certificates;
        System.Text.Encoding;
        System.Text.Encoding.Extensions;
        System.Text.RegularExpressions;
        System.Threading;
        System.Threading.Tasks;
        System.Threading.Timer;
        System.Xml.ReaderWriter;
        System.Xml.XDocument" />
      <!-- That package doesn't bring any dependencies in on .NET Framework and is fine to use. -->
      <NetStandard1xPackage Remove="System.Runtime.InteropServices.RuntimeInformation"
                            Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'" />
    </ItemGroup>
 
    <ItemGroup>
      <NonFoundNetStandard1xPackage Include="@(PackageDependencies)"
                                    Exclude="@(NetStandard1xPackage)" />
      <FoundNetStandard1xPackage Include="@(PackageDependencies)"
                                 Exclude="@(NonFoundNetStandard1xPackage)" />
    </ItemGroup>
 
    <Error Text="The following .NET Standard 1.x packages are referenced and must be removed: %0D%0A- @(FoundNetStandard1xPackage, '%0D%0A- ')%0D%0AConsult the project.assets.json files to find the parent dependencies."
           Condition="'@(FoundNetStandard1xPackage)' != ''" />
  </Target>
 
</Project>