// Copyright (c) Microsoft Corporation. All rights reserved.

// Licensed under the MIT license.

using System;

using System.Collections.Generic;

using System.Threading.Tasks;

using Microsoft.ClearScript.JavaScript;

using Microsoft.ClearScript.Util;

namespace Microsoft.ClearScript.Windows

{

// ReSharper disable once PartialTypeWithSinglePart

/// <summary>

/// Represents an instance of the JScript engine in a desktop environment.

/// </summary>

/// <remarks>

/// Each Windows Script engine instance in a desktop environment has thread affinity and is

/// bound to a <c><see cref="System.Windows.Threading.Dispatcher"/></c> during instantiation.

/// Attempting to execute script code on a different thread results in an exception. Script

/// delegates and event handlers are marshaled synchronously onto the correct thread.

/// </remarks>

public partial class JScriptEngine : WindowsScriptEngine, IJavaScriptEngine, Core.IJScriptEngine

{

#region data

private CommonJSManager commonJSManager;

private JsonModuleManager jsonDocumentManager;

#endregion

#region constructors

/// <summary>

/// Initializes a new JScript engine instance.

/// </summary>

public JScriptEngine()

: this(null)

{

}

/// <summary>

/// Initializes a new JScript engine instance with the specified name.

/// </summary>

/// <param name="name">A name to associate with the instance. Currently, this name is used only as a label in presentation contexts such as debugger user interfaces.</param>

public JScriptEngine(string name)

: this(name, WindowsScriptEngineFlags.None)

{

}

/// <summary>

/// Initializes a new JScript engine instance with the specified options.

/// </summary>

/// <param name="flags">A value that selects options for the operation.</param>

public JScriptEngine(WindowsScriptEngineFlags flags)

: this(null, flags)

{

}

/// <summary>

/// Initializes a new JScript engine instance with the specified name and options.

/// </summary>

/// <param name="name">A name to associate with the instance. Currently, this name is used only as a label in presentation contexts such as debugger user interfaces.</param>

/// <param name="flags">A value that selects options for the operation.</param>

public JScriptEngine(string name, WindowsScriptEngineFlags flags)

: this("JScript", name, "js", flags)

{

}

/// <summary>

/// Initializes a new JScript engine instance with the specified programmatic

/// identifier, name, list of supported file name extensions, and options.

/// </summary>

/// <param name="progID">The programmatic identifier (ProgID) of the JScript engine class.</param>

/// <param name="name">A name to associate with the instance. Currently, this name is used only as a label in presentation contexts such as debugger user interfaces.</param>

/// <param name="fileNameExtensions">A semicolon-delimited list of supported file name extensions.</param>

/// <param name="flags">A value that selects options for the operation.</param>

/// <remarks>

/// The <paramref name="progID"/> argument can be a class identifier (CLSID) in standard

/// GUID format with braces (e.g., "{F414C260-6AC0-11CF-B6D1-00AA00BBBB58}").

/// </remarks>

protected JScriptEngine(string progID, string name, string fileNameExtensions, WindowsScriptEngineFlags flags)

: base(progID, name, fileNameExtensions, flags)

{

Execute(MiscHelpers.FormatInvariant("{0} [internal]", GetType().Name), Core.JScriptEngine.InitScript);

}

#endregion

#region internal members

internal CommonJSManager CommonJSManager => commonJSManager ?? (commonJSManager = new CommonJSManager(this));

internal JsonModuleManager JsonModuleManager => jsonDocumentManager ?? (jsonDocumentManager = new JsonModuleManager(this));

#endregion

#region ScriptEngine overrides

/// <summary>

/// Gets the script engine's recommended file name extension for script files.

/// </summary>

/// <remarks>

/// <c><see cref="JScriptEngine"/></c> instances return "js" for this property.

/// </remarks>

public override string FileNameExtension => "js";

/// <summary>

/// Executes script code as a command.

/// </summary>

/// <param name="command">The script command to execute.</param>

/// <returns>The command output.</returns>

/// <remarks>

/// <para>

/// This method is similar to <c><see cref="ScriptEngine.Evaluate(string)"/></c> but optimized for

/// command consoles. The specified command must be limited to a single expression or

/// statement. Script engines can override this method to customize command execution as

/// well as the process of converting the result to a string for console output.

/// </para>

/// <para>

/// The <c><see cref="JScriptEngine"/></c> version of this method attempts to use

/// <c><see href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/tostring">toString</see></c>

/// to convert the return value.

/// </para>

/// </remarks>

public override string ExecuteCommand(string command)

{

var engineInternal = (ScriptObject)Global.GetProperty("EngineInternal");

engineInternal.SetProperty("command", command);

return base.ExecuteCommand("EngineInternal.getCommandResult(eval(EngineInternal.command))");

}

internal override IDictionary<int, string> RuntimeErrorMap => Core.JScriptEngine.StaticRuntimeErrorMap;

internal override IDictionary<int, string> SyntaxErrorMap => Core.JScriptEngine.StaticSyntaxErrorMap;

internal override object Execute(UniqueDocumentInfo documentInfo, string code, bool evaluate)

{

if (FormatCode)

{

code = MiscHelpers.FormatCode(code);

}

if (documentInfo.Category == ModuleCategory.CommonJS)

{

var module = CommonJSManager.GetOrCreateModule(documentInfo, code);

return ScriptInvoke(static module => module.Process(), module);

}

if (documentInfo.Category != DocumentCategory.Script)

{

throw new NotSupportedException("The script engine cannot execute documents of type '" + documentInfo.Category + "'");

}

return base.Execute(documentInfo, code, evaluate);

}

#endregion

#region IJavaScriptEngine implementation

uint IJavaScriptEngine.BaseLanguageVersion => 3;

CommonJSManager IJavaScriptEngine.CommonJSManager => CommonJSManager;

JsonModuleManager IJavaScriptEngine.JsonModuleManager => JsonModuleManager;

object IJavaScriptEngine.CreatePromiseForTask<T>(Task<T> task)

{

throw new NotImplementedException();

}

object IJavaScriptEngine.CreatePromiseForTask(Task task)

{

throw new NotImplementedException();

}

object IJavaScriptEngine.CreatePromiseForValueTask<T>(ValueTask<T> valueTask)

{

throw new NotImplementedException();

}

object IJavaScriptEngine.CreatePromiseForValueTask(ValueTask valueTask)

{

throw new NotImplementedException();

}

Task<object> IJavaScriptEngine.CreateTaskForPromise(ScriptObject promise)

{

throw new NotImplementedException();

}

#endregion

}

}