using Jint.Native.Promise;
using Jint.Runtime.Environments;
using Environment = Jint.Runtime.Environments.Environment;

namespace Jint;

public partial class Engine
{
    public AdvancedOperations Advanced { get; }
}

public class AdvancedOperations
{
    private readonly Engine _engine;

    public AdvancedOperations(Engine engine)
    {
        _engine = engine;
    }

    /// <summary>
    /// Gets current stack trace that is active in engine.
    /// </summary>
    public string StackTrace
    {
        get
        {
            var lastSyntaxElement = _engine._lastSyntaxElement;
            if (lastSyntaxElement is null)
            {
                return string.Empty;
            }

            return _engine.CallStack.BuildCallStackString(lastSyntaxElement.Location);
        }
    }

    /// <summary>
    /// Initializes list of references of called functions
    /// </summary>
    public void ResetCallStack()
    {
        _engine.ResetCallStack();
    }

    /// <summary>
    /// Forcefully processes the current task queues (micro and regular), this API may break and change behavior!
    /// </summary>
    public void ProcessTasks()
    {
        _engine.RunAvailableContinuations();
    }

    /// <summary>
    /// Creates a new declarative environment that has current lexical environment as outer scope.
    /// </summary>
    public Environment CreateDeclarativeEnvironment()
    {
        return JintEnvironment.NewDeclarativeEnvironment(_engine, _engine.ExecutionContext.LexicalEnvironment);
    }

    /// <summary>
    /// EXPERIMENTAL! Subject to change.
    ///
    /// Registers a promise within the currently running EventLoop (has to be called within "ExecuteWithEventLoop" call).
    /// Note that ExecuteWithEventLoop will not trigger "onFinished" callback until ALL manual promises are settled.
    ///
    /// NOTE: that resolve and reject need to be called withing the same thread as "ExecuteWithEventLoop".
    /// The API assumes that the Engine is called from a single thread.
    /// </summary>
    /// <returns>a Promise instance and functions to either resolve or reject it</returns>
    public ManualPromise RegisterPromise()
    {
        return _engine.RegisterPromise();
    }
}