using System.Collections.Generic;
using System.Diagnostics;
using Timer=System.Threading.Timer;
namespace Tidstagning
{
    class Procedure
    {
        Relay? horn;
        ResultList? log;
        List<DateTime> signaler;
        uint signalLength = 500;

        Timer? delayTimer;
        Int16 idx = 0;

        public Procedure()
        {
            signaler = new List<DateTime>();
        }

        public void ReadFile(string file)
        {
            System.IO.StreamReader procedure_handle = new System.IO.StreamReader(file);
            string? line;
            while ((line = procedure_handle.ReadLine()) != null)
            {
                addEntry(line);
            }
            procedure_handle.Dispose();
        }

        public void addEntry(string input)
        {
            string input_filtered = input.Trim();
            if (input_filtered.Length > 0)
            {
                try
                {
                    signaler.Add(DateTime.Parse(input_filtered));
                }
                catch
                {
                    Debug.WriteLine("Failed to parse: " + input);
                }
                signaler.Sort();
            }
        }

        public string TextualRepresentation()
        {
            string t = "";
            if (signaler.Count > 0)
            {
                foreach (DateTime signal in signaler)
                {
                    if (DateTime.Now > (signal.AddMilliseconds(signalLength)))
                    {
                        t += "✔";
                    }
                    else if (DateTime.Now > signal)
                    {
                        t += "o ";
                    }
                    else
                    {
                        t += "  ";
                    }
                    t += signal.ToString() + "\r\n";
                }
            }
            return t;
        }

        public void Clear()
        {
            signaler = new List<DateTime>();
            idx = 0;
            if (delayTimer != null)
                delayTimer.Dispose();
        }

        public void setObjects(Relay horn_obj, ResultList log_obj)
        {
            this.horn = horn_obj;
            this.log = log_obj;
            Run();
        }

        public void adjustSignalLength(uint lengthMS)
        {
            signalLength = lengthMS;
        }

        public void Run()
        {
            if (signaler.Count > 0)
            {
                SetUpTimer(signaler[idx]);
            }

        }
        private void SetUpTimer(DateTime alertTime)
        {
            DateTime current = DateTime.Now;
            TimeSpan timeToGo = alertTime.TimeOfDay - current.TimeOfDay;

            if (timeToGo < TimeSpan.Zero)
            {
                if (!next())
                {
                    return;
                }
                Run();
                return;//time already passed
            }
            if (log is not null)
            {
                log.Write("Næste signal: " + alertTime.ToString(@"HH\:mm\:ss") + " Om: " + timeToGo.ToString(@"hh\:mm\:ss"));
            }
            delayTimer = new Timer(x =>
             {
                 this.Alarm();
             }, null, timeToGo, new TimeSpan(0));
        }

        private void Alarm()
        {
            if(log is not null)
                log.Write("HORN!");
            if(horn is not null)
                horn.Sound(signalLength);
            next();
            Run();

        }

        private bool next()
        {
            if (idx >= (signaler.Count - 1))
                return false;

            idx++;
            return true;
        }
    }
}