src/ScriptEngine/Machine/MachineStopManager.cs - develop - smwwiki/OneScript_fork

src/ScriptEngine/Machine/MachineStopManager.cs
132 строки5 KB
akpaevj
Небольшой рефакторинг
07 авг 2024, 18:53
07 авг 2024, 18:53f60c8fe
/*----------------------------------------------------------
This Source Code Form is subject to the terms of the 
Mozilla Public License, v.2.0. If a copy of the MPL 
was not distributed with this file, You can obtain one 
at http://mozilla.org/MPL/2.0/.
----------------------------------------------------------*/

using System;
using System.Linq;

namespace ScriptEngine.Machine
{

    internal enum DebugState
    {
        Running,
        SteppingOver,
        SteppingIn,
        SteppingOut
    }

    internal class MachineStopManager
    {
        private struct StopPoint
        {
            public ExecutionFrame frame;
            public int line;
        }

        private DebugState _currentState = DebugState.Running;
        private readonly IBreakpointManager _breakpoints;
        private readonly MachineInstance _machine;
        private ExecutionFrame[] _stopFrames;
        
        public MachineStopManager(MachineInstance runner, IBreakpointManager breakpoints)
        {
            _machine = runner ?? throw new ArgumentNullException(nameof(runner));
            _breakpoints = breakpoints ?? throw new ArgumentNullException(nameof(runner));
        }
        
        public IBreakpointManager Breakpoints => _breakpoints;
        public MachineStopReason LastStopReason { get; internal set; }
        public string LastStopErrorMessage { get; internal set; }
        public DebugState CurrentState => _currentState;

        public bool ShouldStopAtThisLine(string module, ExecutionFrame currentFrame)
        {
            bool mustStop = false;

            switch (_currentState)
            {
                case DebugState.Running:
                    mustStop = HitBreakpointOnLine(module, currentFrame);
                    break;
                case DebugState.SteppingIn:
                    mustStop = true;
                    break;
                case DebugState.SteppingOut:
                case DebugState.SteppingOver:
                    mustStop = FrameIsInStopList(currentFrame);
                    // по пути следования все равно может встретиться breakpoint
                    if (!mustStop && HitBreakpointOnLine(module, currentFrame))
                    {
                        _currentState = DebugState.Running; //для правильной причины останова (см. ниже)
                        mustStop = true;
                    }
                    break;
            }

            if (mustStop)
            {
                if (_currentState == DebugState.Running)
                {
                    LastStopReason = MachineStopReason.Breakpoint;

                    // Проверим существование условия остановки
                    var condition = Breakpoints.GetCondition(module, currentFrame.LineNumber);

                    if (!string.IsNullOrEmpty(condition))
                    {
                        try
                        {
                            mustStop = _machine.EvaluateInFrame(condition, currentFrame).AsBoolean();
                        }
                        catch (Exception ex)
                        {
                            // Остановим и сообщим, что остановка произошла не по условию, а в результате ошибки вычисления
                            mustStop = true;
                            LastStopReason = MachineStopReason.BreakpointConditionError;
                            LastStopErrorMessage = $"Не удалось выполнить условие точки останова: {ex.Message}";
                        }
                    }
                }
                else
                    LastStopReason = MachineStopReason.Step;

                _currentState = DebugState.Running;
            }

            return mustStop;
            
        }
        
        private bool HitBreakpointOnLine(string module, ExecutionFrame currentFrame)
        {
            return _breakpoints.FindBreakpoint(module, currentFrame.LineNumber);
        }

        private bool FrameIsInStopList(ExecutionFrame currentFrame)
        {
            return _stopFrames != null && _stopFrames.Contains(currentFrame);
        }

        public void StepOver()
        {
            _currentState = DebugState.SteppingOver;
            _stopFrames = _machine.GetExecutionFrames().Select(x => x.FrameObject).ToArray();

        }

        public void StepIn()
        {
            _currentState = DebugState.SteppingIn;
        }

        internal void StepOut()
        {
            _currentState = DebugState.SteppingOut;
            _stopFrames = _machine.GetExecutionFrames().Select(x => x.FrameObject).Skip(1).ToArray();
        }
    }
}