// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
#nullable disable
 
using System;
using System.Linq;
using EnvDTE;
using Microsoft.CodeAnalysis.Test.Utilities;
using Microsoft.VisualStudio.LanguageServices.Implementation.Interop;
using Roslyn.Test.Utilities;
using SyntaxNodeKey = Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.SyntaxNodeKey;
 
namespace Microsoft.VisualStudio.LanguageServices.CSharp.UnitTests.CodeModel;
 
/// <summary>
/// Base class of a all test-containing classes. Automatically creates a FileCodeModel for testing with the given
/// file.
/// </summary>
[UseExportProvider]
public abstract class AbstractFileCodeElementTests : IDisposable
{
    private readonly string _contents;
    private (EditorTestWorkspace workspace, FileCodeModel fileCodeModel)? _workspaceAndCodeModel;
 
    protected AbstractFileCodeElementTests(string contents)
    {
        _contents = contents;
    }
 
    public (EditorTestWorkspace workspace, FileCodeModel fileCodeModel) WorkspaceAndCodeModel
    {
        get
        {
            return _workspaceAndCodeModel ??= CreateWorkspaceAndFileCodeModelAsync(_contents);
        }
    }
 
    protected EditorTestWorkspace GetWorkspace()
    {
        return WorkspaceAndCodeModel.workspace;
    }
 
    protected FileCodeModel GetCodeModel()
    {
        return WorkspaceAndCodeModel.fileCodeModel;
    }
 
    protected Microsoft.CodeAnalysis.Solution GetCurrentSolution()
        => GetWorkspace().CurrentSolution;
 
    protected Microsoft.CodeAnalysis.Project GetCurrentProject()
        => GetCurrentSolution().Projects.Single();
 
    protected Microsoft.CodeAnalysis.Document GetCurrentDocument()
        => GetCurrentProject().Documents.Single();
 
    protected static (EditorTestWorkspace workspace, FileCodeModel fileCodeModel) CreateWorkspaceAndFileCodeModelAsync(string file)
        => FileCodeModelTestHelpers.CreateWorkspaceAndFileCodeModel(file);
 
    protected CodeElement GetCodeElement(params object[] path)
    {
        WpfTestRunner.RequireWpfFact($"Tests create {nameof(CodeElement)}s which use the affinitized {nameof(CleanableWeakComHandleTable<SyntaxNodeKey, CodeElement>)}");
 
        if (path.Length == 0)
        {
            throw new ArgumentException("path must be non-empty.", nameof(path));
        }
 
        var codeElement = (GetCodeModel()).CodeElements.Item(path[0]);
 
        foreach (var pathElement in path.Skip(1))
        {
            codeElement = codeElement.Children.Item(pathElement);
        }
 
        return codeElement;
    }
 
    public void Dispose()
    {
        GetWorkspace().Dispose();
    }
 
    /// <summary>
    /// Returns the current text of the test buffer.
    /// </summary>
    protected string GetFileText()
    {
        return (GetWorkspace()).Documents.Single().GetTextBuffer().CurrentSnapshot.GetText();
    }
}