// 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.
 
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CodeStyle;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.CodeStyle;
using Microsoft.CodeAnalysis.CSharp.ConvertProgram;
using Microsoft.CodeAnalysis.Editor.UnitTests.CodeActions;
using Microsoft.CodeAnalysis.Test.Utilities;
using Microsoft.CodeAnalysis.Testing;
using Roslyn.Test.Utilities;
using Xunit;
 
namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.ConvertProgram;
 
using VerifyCS = CSharpCodeRefactoringVerifier<ConvertToTopLevelStatementsCodeRefactoringProvider>;
 
[UseExportProvider]
public sealed class ConvertToTopLevelStatementsRefactoringTests
{
    [Fact]
    public Task TestNotOnEmptyFile()
        => new VerifyCS.Test
        {
            TestCode = """
            $$
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            ExpectedDiagnostics =
            {
                // error CS5001: Program does not contain a static 'Main' method suitable for an entry point
                DiagnosticResult.CompilerError("CS5001"),
            }
        }.RunAsync();
 
    [Fact]
    public Task TestConvertToTopLevelStatementsWithDefaultTopLevelStatementPreference()
        => new VerifyCS.Test
        {
            TestCode = """
            class Program
            {
                static void $$Main(string[] args)
                {
                    System.Console.WriteLine(args[0]);
                }
            }
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
        }.RunAsync();
 
    [Fact]
    public Task TestConvertToTopLevelStatementsWithProgramMainPreferenceSuggestion()
        => new VerifyCS.Test
        {
            TestCode = """
            class Program
            {
                static void $$Main(string[] args)
                {
                    System.Console.WriteLine(args[0]);
                }
            }
            """,
            FixedCode = """
            System.Console.WriteLine(args[0]);
 
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            }
        }.RunAsync();
 
    [Fact]
    public Task TestNotOfferedInLibrary()
        => new VerifyCS.Test
        {
            TestCode = """
            class Program
            {
                static void $$Main(string[] args)
                {
                    System.Console.WriteLine(args[0]);
                }
            }
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            }
        }.RunAsync();
 
    [Fact]
    public Task TestNotWithNonViableType()
        => new VerifyCS.Test
        {
            TestCode = """
            class Program
            {
                void $$Main(string[] args)
                {
                    System.Console.WriteLine(args[0]);
                }
            }
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            },
            ExpectedDiagnostics =
            {
                // error CS5001: Program does not contain a static 'Main' method suitable for an entry point
                DiagnosticResult.CompilerError("CS5001"),
            }
        }.RunAsync();
 
    [Fact]
    public Task TestNoConvertToTopLevelStatementsWithProgramMainPreferenceSuggestionBeforeCSharp9()
        => new VerifyCS.Test
        {
            TestCode = """
            class Program
            {
                static void $$Main(string[] args)
                {
                    System.Console.WriteLine(args[0]);
                }
            }
            """,
            LanguageVersion = LanguageVersion.CSharp8,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            }
        }.RunAsync();
 
    [Fact]
    public Task TestNoConvertToTopLevelStatementsWithTopLevelStatementsPreferenceSuggestion()
        => new VerifyCS.Test
        {
            TestCode = """
            class Program
            {
                static void $$Main(string[] args)
                {
                    System.Console.WriteLine(args[0]);
                }
            }
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, true, NotificationOption2.Suggestion },
            }
        }.RunAsync();
 
    [Fact]
    public Task TestNoConvertToTopLevelStatementsWithTopLevelStatementsPreferenceSilent()
        => new VerifyCS.Test
        {
            TestCode = """
            class Program
            {
                static void $$Main(string[] args)
                {
                    System.Console.WriteLine(args[0]);
                }
            }
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, true, NotificationOption2.Silent },
            }
        }.RunAsync();
 
    [Fact]
    public Task TestConvertToTopLevelStatementWithTopLevelStatementPreferenceSuppress()
        => new VerifyCS.Test
        {
            TestCode = """
            internal class Program
            {
                private static void $$Main(string[] args)
                {
                    System.Console.WriteLine(0);
                }
            }
            """,
            FixedCode = """
            System.Console.WriteLine(0);
 
            """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, true, NotificationOption2.None },
            }
        }.RunAsync();
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/78002")]
    public Task TestPreserveStatementDirectives1()
        => new VerifyCS.Test
        {
            TestCode = """
                using System;
 
                class Program
                {
                    static void $$Main(string[] args)
                    {
                #if true
                        Console.WriteLine("true");
                #else
                        Console.WriteLine("false");
                #endif
                    }
                }
                """,
            FixedCode = """
                using System;
 
                #if true
                Console.WriteLine("true");
                #else
                        Console.WriteLine("false");
                #endif
 
                """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            }
        }.RunAsync();
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/78002")]
    public Task TestPreserveStatementDirectives2()
        => new VerifyCS.Test
        {
            TestCode = """
                using System;
 
                class Program
                {
                    static void $$Main(string[] args)
                    {
                #if true
                        Console.WriteLine("true");
                #else
                        Console.WriteLine("false");
                #endif
                    }
                }
 
                class Next
                {
                }
                """,
            FixedCode = """
                using System;
 
                #if true
                Console.WriteLine("true");
                #else
                        Console.WriteLine("false");
                #endif
            
                class Next
                {
                }
                """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            }
        }.RunAsync();
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/78002")]
    public Task TestPreserveStatementDirectives3()
        => new VerifyCS.Test
        {
            TestCode = """
                using System;
 
                namespace N
                {
                    class Program
                    {
                        static void $$Main(string[] args)
                        {
                    #if true
                            Console.WriteLine("true");
                    #else
                            Console.WriteLine("false");
                    #endif
                        }
                    }
                }
                """,
            FixedCode = """
                using System;
 
                #if true
                Console.WriteLine("true");
                #else
                            Console.WriteLine("false");
                #endif
 
                """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            }
        }.RunAsync();
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/78002")]
    public Task TestPreserveStatementDirectives4()
        => new VerifyCS.Test
        {
            TestCode = """
                using System;
 
                namespace N
                {
                    class Program
                    {
                        static void $$Main(string[] args)
                        {
                    #if true
                            Console.WriteLine("true");
                    #else
                            Console.WriteLine("false");
                    #endif
                        }
                    }
 
                    class Next
                    {
                    }
                }
                """,
            FixedCode = """
                using System;
 
                #if true
                Console.WriteLine("true");
                #else
                            Console.WriteLine("false");
                #endif
                
                namespace N
                {
                    class Next
                    {
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp10,
            TestState = { OutputKind = OutputKind.ConsoleApplication },
            Options =
            {
                { CSharpCodeStyleOptions.PreferTopLevelStatements, false, NotificationOption2.Suggestion },
            }
        }.RunAsync();
}