using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;

#pragma warning disable 0414
namespace MECF.Framework.Common.Routine
{
    public class RoutineRunner
    {
        public enum State
        {
            Init,
            Running,
            End,
            Failed,
            Timeout,
        }

        
        private State       _subState = State.Init;
        private Stack<int>  _step = new Stack<int>();
        private int         _curStep = int.MaxValue;
        private State     _runnerState = State.Init;

        Stopwatch _subStepTimer = new Stopwatch();

        public RoutineRunner()
        {
            _runnerState = State.Init;
        }

        public void Reset()
        {
            _runnerState = State.Init;
            _subState = State.Init;
            _step.Clear();
        }

        public RoutineRunner Start(int id, Func<bool> action,  Func<bool> condition, int timeout)
        {
            if (!_step.Contains(id))
            {
                _runnerState = State.Running;
                startNewStep(id, action);
            }
            else
            {
                if (_subState == State.Running)
                {
                    if(condition())
                    {
                        _subState = State.End;
                    }
                    else
                    {
                        if (_subStepTimer.ElapsedMilliseconds > timeout)
                        {
                            _runnerState = State.Failed;
                            _subState = State.Timeout;
                        }
                    }
                }
            }
                
            return this;
        }

        public RoutineRunner Start(int id, Func<bool> action, int timeout)
        {
            if (!_step.Contains(id))
            {
                _runnerState = State.Running;
                startNewStep(id, action);
            }
            else
            {
                if (_subStepTimer.ElapsedMilliseconds > timeout)
                {
                    _subState = State.End;
                }
            }


            return this;
        }

        public RoutineRunner Continue(int id, Func<bool> action, Func<bool> condition, int timeout)
        {
            if (_subState == State.End && !_step.Contains(id))
            {
                startNewStep(id, action);
            }
            else if(_curStep == id && _subState == State.Running)
            {
                if (condition())
                {
                    _subState = State.End;
                }
                else
                {
                    if (_subStepTimer.ElapsedMilliseconds > timeout)
                    {
                        _runnerState = State.Failed;
                        _subState = State.Timeout;
                    }
                }
            }

            return this;
        }

        public RoutineRunner Continue(int id, Func<bool> action, int timeout)
        {
            if (_subState == State.End && !_step.Contains(id))
            {
                startNewStep(id, action);
            }
            else if (_curStep == id && _subState == State.Running)
            {
                if (_subStepTimer.ElapsedMilliseconds > timeout)
                {
                    _subState = State.End;
                }
            }

            return this;
        }

        public RoutineRunner End(int id, Func<bool> action, Func<bool> condition, int timeout)
        {
            if (_subState == State.End && !_step.Contains(id))
            {
                startNewStep(id, action);
            }
            else if (_curStep == id && _subState == State.Running)
            {
                if (condition())
                {
                    _runnerState = State.End;
                    _subState = State.End;
                }
                else
                {
                    if (_subStepTimer.ElapsedMilliseconds > timeout)
                    {
                        _runnerState = State.Failed;
                        _subState = State.Timeout;
                    }
                }
            }

            return this;
        }

        public RoutineRunner End(int id, Func<bool> action, int timeout)
        {
            if (_subState == State.End && !_step.Contains(id))
            {
                startNewStep(id, action);
            }
            else if (_curStep == id && _subState == State.Running)
            {
                if (_subStepTimer.ElapsedMilliseconds > timeout)
                {
                    _runnerState = State.End;
                    _subState = State.End;
                }
            }

            return this;
        }

        private void startNewStep(int id, Func<bool> action)
        {
            if (action())
            {
                _step.Push(id);
                _curStep = id;
                _subState = State.Running;
                _subStepTimer.Restart();
            }
            else
            {
                _runnerState = State.Failed;
            }
        }
    }
}